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Mar 31, 2020·IEEE Transactions on Industrial Informatics
59 cites
Achieving Accountable and Efficient Data Sharing in Industrial Internet of Things

Cheng Huang, Dongxiao Liu, Jianbing Ni, Rongxing Lu · 5 authors

In this article, we propose an accountable and efficient data sharing scheme for industrial IoT (IIoT), named an accountable and data sharing scheme (ADS), in which a data owner can pursue the responsibility of a data receiver if the latter leaks some sensitive shared data to the public for profits while without permission (i.e., accountability). Specifically, ADS is built upon an adaptive decentralized oblivious transfer protocol together with a zero-knowledge proof technique, which enables the data receiver's private key to be hidden from the data owner and yet correctly embedded into the shared data during the process of data sharing. Once data breaches occur, the private key can be automatically revealed to the data owner so as to achieve the accountability. In addition, with ADS, a group of sharing providers can also assist IIoT devices in handling heavy computational tasks via the secret sharing technique without sacrificing the security. Extensive performance evaluations are conducted, and the simulation results demonstrate that ADS has high computational efficiency, making it well fit for IIoT.

Blockchain Technology Applications and Security
Cryptography and Data Security
Privacy-Preserving Technologies in Data
Original source
Mar 30, 2020·International Journal of Recent Technology and Engineering (IJRTE)
0 cites
A Zero-Proof Knowledge Based on NFC for Data Authentication/Protection using Blockchain for Mobile Edge Computing

Hanumantharaju R, K. N. Shreenath, K. G. Srinivasa, Swetha Namburu

Mobile edge computing is a recent trend to complement the Internet of Things (IoT) ecosystem in the computing sector. IoT is the internet connected communications related to physical devices and everyday objects. The emergence of intelligent living spaces has been due to the rapid development of IoT technologies. Blockchain is one such technology that expands the list of information also referred to like records that are saved as blocks in the Blockchain which are connected using cryptographic algorithms. Within a Blockchain IoT environment, when data or device authentication information is stored in a Blockchain, authentication information can be displayed when verifying Block chain’s transactions, which are also referred to as proof of work. A principle of Zero-knowledge proof (ZKF) is implemented in this paper which is a way of proving that knowledge is known without exposing any data to the user. The proposed model uses a Mobile application where users can prove without revealing users' passwords. Blockchain stores client information that can prevent data from being manipulated. The results of applying the ZKF theory for data security are shown through a web application and NFC.

Open access
Blockchain Technology Applications and Security
User Authentication and Security Systems
IoT and Edge/Fog Computing
Original source
Mar 29, 2020·Proceedings of the 35th Annual ACM Symposium on Applied Computing
4 cites
PrivateEx

Lei Xu, Lin Chen, Zhimin Gao, Keshav Kasichainula · 7 authors

Bitcoin introduces a new type of cryptocurrency that does not rely on a central system to maintain transactions. Inspired by the success of Bitcoin, all types of alt cryptocurrencies were invented in recent years. Some of the new cryptocurrencies focus on privacy enhancement, where transaction information such as value and sender/receiver identity can be hidden, such as Zcash and Monero. However, there are few schemes to support multiple types of cryptocurrencies/assets and offer privacy enhancement at the same time. The major challenge for a multiple asset system is that it needs to support two-way assets exchange between participants besides one-way asset transfer. Thus, we propose a privacy-preserving exchange scheme, PrivateEx, which preserves the privacy of the exchange of different assets. PrivateEx utilizes zero-knowledge proof and a novel way to "lock" assets involved in the exchange to guarantee the correctness, fairness, and privacy of exchange of assets in the system. We also implement a prototype of PrivateEx and evaluate its performance to show that it is practical with modern computers.

Open access
Blockchain Technology Applications and Security
Cryptography and Data Security
Privacy-Preserving Technologies in Data
Original source
Mar 25, 2020·International Journal of Innovative Research in Engineering & Multidisciplinary Physical Sciences
0 cites
Significance of Data Structures and Algorithms in Financial Technology

Ashmitha Nagraj

Financial Technology (FinTech) has transformed Capital Markets, Payments, Lending and Risk Management through faster processing of financial decisions in real-time and expanding access to financial services digitally. Beneath these user-friendly applications, FinTech platforms rely on foundational Data Structures and Algorithms to provide consistent Latency, Scalable Throughput, Auditing capabilities, and Resilience under adversarial conditions. The purpose of this paper is to review which core Data Structures (Arrays, Linked Lists, Hash Tables, Balanced Trees, Heaps and Graphs) are used to support key FinTech Workload applications (Algorithmic Trading, Fraud Detection, Credit Risk Assessment and Blockchain-based Recordkeeping). In addition, this paper will review the Algorithmic Foundations used to enable common tasks across all these workload applications including Sorting/Searching, Optimization, Statistical Learning and Cryptography, and how Asymptotic Complexity must be evaluated with respect to practical system constraints including Caching Behavior, Concurrency and Failure Modes. There is evidence from the academic literature that Algorithmic Trading can increase liquidity in certain Market Structures while also introducing Systemic Fragility during Stress [1],[2],[3]. And, similarly, there is evidence that Fraud Detection is an inherently adversarial domain where Models and Features must evolve as Attacker Behavior evolves [4],[5]. Lastly, the Paper will discuss several open challenges associated with Scale, Security, Model Governance and Privacy; and evaluate Future-Facing Directions such as Privacy-Preserving Analytics (Federated Learning and Zero-Knowledge Proofs) and Cryptographic Agility to prepare for post-Quantum risk.

Open access
Blockchain Technology Applications and Security
Stock Market Forecasting Methods
FinTech, Crowdfunding, Digital Finance
Original source
Mar 24, 2020·arXiv (Cornell University)
3 cites
Information-theoretically-sound non-interactive classical verification of quantum computing with trusted center

Tomoyuki Morimae

The posthoc verification protocol [J. F. Fitzsimons, M. Hajdu{\v s}ek, and T. Morimae, Physical Review Letters {\bf120}, 040501 (2018)] enables an information-theoretically-sound non-interactive verification of quantum computing, but the message from the prover to the verifier is quantum and the verifier has to do single-qubit measurements. The Mahadev protocol removes these quantum parts, but the soundness becomes the computational one. In this paper, we construct an information-theoretically-sound non-interactive classical verification protocol for quantum computing with a trusted center. The trusted center sends random BB84 states to the prover, and the classical descriptions of these BB84 states to the verifier. The messages from the center to the prover and the verifier are independent of the instance. By slightly modifying our protocol, we also construct a non-interactive statistical zero-knowledge proof system for QMA with the trusted center.

Open access
2 source records
quant-ph
cs.CC
cs.CR
Original source
Mar 23, 2020·arXiv
0 cites
Dragoon: Private Decentralized HITs Made Practical

Yuan Lu, Qiang Tang, Guiling Wang

With the rapid popularity of blockchain, decentralized human intelligence tasks (HITs) are proposed to crowdsource human knowledge without relying on vulnerable third-party platforms. However, the inherent limits of blockchain cause decentralized HITs to face a few "new" challenges. For example, the confidentiality of solicited data turns out to be the sine qua non, though it was an arguably dispensable property in the centralized setting. To ensure the "new" requirement of data privacy, existing decentralized HITs use generic zero-knowledge proof frameworks (e.g. SNARK), but scarcely perform well in practice, due to the inherently expensive cost of generality. We present a practical decentralized protocol for HITs, which also achieves the fairness between requesters and workers. At the core of our contributions, we avoid the powerful yet highly-costly generic zk-proof tools and propose a special-purpose scheme to prove the quality of encrypted data. By various non-trivial statement reformations, proving the quality of encrypted data is reduced to efficient verifiable decryption, thus making decentralized HITs practical. Along the way, we rigorously define the ideal functionality of decentralized HITs and then prove the security due to the ideal-real paradigm. We further instantiate our protocol to implement a system called Dragoon, an instance of which is deployed atop Ethereum to facilitate an image annotation task used by ImageNet. Our evaluations demonstrate its practicality: the on-chain handling cost of Dragoon is even less than the handling fee of Amazon's Mechanical Turk for the same ImageNet HIT.

Open access
2 source records
cs.CR
cs.HC
Blockchain Technology Applications and Security
Original source
Mar 13, 2020·Complexity
2 cites
A Group Identification Protocol with Leakage Resilience of Secret Sharing Scheme

Ping Li, Shengjun Li, Hongyang Yan, Lishan Ke · 6 authors

Secret sharing has been study for many years and has had a number of real-word applications. There are several methods to construct the secret-sharing schemes. One of them is based on coding theory. In this work, we construct a secret-sharing scheme that realizes an access structure by using linear codes, in which any element of the access structure can reconstruct the secret key. We prove that our scheme is a multiprover zero-knowledge proof system in the random oracle model, which shows that a passive adversary gains no information about the secret key. Our scheme is also a leakage-resilient secret-sharing scheme (LRSS) in the bounded-leakage model, which remain provably secure even if the adversary learns a bounded amount of leakage information about their secret key. As an application, we propose a new group identification protocol (GID-scheme) from our LRSS. We prove that our GID-scheme is a leakage-resilient scheme. In our leakage-resilient GID-scheme, the verifier believes the validity of qualified group members and tolerates l bits of adversarial leakage in the distribution protocol, whereas for unqualified group members, the verifier cannot believe their valid identifications in the proof protocol.

Open access
Cryptography and Data Security
Security in Wireless Sensor Networks
Advanced Authentication Protocols Security
Original source
Mar 13, 2020·Proceedings of the Tenth ACM Conference on Data and Application Security and Privacy
9 cites
ZeroLender

Yi Xie, Joshua Holmes, Gaby G. Dagher

Since its inception a decade ago, Bitcoin and its underlying blockchain technology have been garnering interest from a large spectrum of financial institutions. Although it encompasses a currency, a payment method, and a ledger, Bitcoin as it currently stands does not support bitcoins lending. In this paper, we present a platform called ZeroLender for peer-to-peer lending in Bitcoin. Our protocol utilizes zero-knowledge proofs to achieve unlinkability between lenders and borrowers while securing payments in both directions against potential malicious behaviour of the ZeroLender as well as the lenders, and prove by simulation that our protocol is privacy-preserving. Based on our experiments, we show that the runtime and transcript size of our protocol scale linearly with respect to the number of lenders and repayments.

Blockchain Technology Applications and Security
Cryptography and Data Security
Advanced Steganography and Watermarking Techniques
Original source
Mar 13, 2020·IEEE Transactions on Vehicular Technology
24 cites
DAPA: A Decentralized, Accountable, and Privacy-Preserving Architecture for Car Sharing Services

Cheng Huang, Rongxing Lu, Jianbing Ni, Xuemin Shen

Car sharing offers a flexible peer-to-peer or station based car rental service to customers. On one hand, it requires customers to expose identifications (e.g., valid driving licenses) to car sharing service providers (CSSPs) for accountability, i.e., the driving qualification of customers can be verified and misbehaving customers can be traced by CSSPs. On the other hand, privacy concerns arise when customers identities are exposed as honest-but-curious CSSPs may secretly extract customers privacy information by linking their car rental records to their identities. To resolve this contradiction, we propose a decentralized, accountable, and privacy-preserving architecture for car sharing services, named DAPA. In specific, to overcome the limitation of the single point of failure, multiple dynamic validation servers are employed to substitute a single trusted third-party authority and assist in building decentralized trust for customers. In addition, to protect customers' privacy and achieve accountability simultaneously under the decentralized architecture, a new privacy-preserving identity management (PPIM) scheme is introduced as a basic module for DAPA. Customers' identities are protected in a distributed and dynamic manner but publicly verified based on a well-designed zero-knowledge proof protocol. Only the misbehaving customers' identities can be recovered by a majority of validation servers using adaptive verifiable secret sharing/redistribution techniques. Detailed security analysis shows that DAPA can minimize privacy breaches and guarantee the accountability. Performance evaluations via extensive simulations demonstrate that DAPA is efficient in terms of computational costs and communication overheads.

Cryptography and Data Security
Privacy-Preserving Technologies in Data
Blockchain Technology Applications and Security
Original source
Mar 13, 2020·arXiv (Cornell University)
2 cites
PayPlace: Secure and Flexible Operator-Mediated Payments in Blockchain Marketplaces at Scale

Madhumitha Harishankar, Dimitrios-Georgios Akestoridis, Sriram V. Iyer, Áron Lászka · 6 authors

Decentralized marketplace applications demand fast, cheap and easy-to-use cryptocurrency payment mechanisms to facilitate high transaction volumes. The standard solution for off-chain payments, state channels, are optimized for frequent transactions between two entities and impose prohibitive liquidity and capital requirements on payment senders for marketplace transactions. We propose PayPlace, a scalable off-chain protocol for payments between consumers and sellers. Using PayPlace, consumers establish a virtual unidirectional payment channel with an intermediary operator to pay for their transactions. Unlike state channels, however, the PayPlace operator can reference the custodial funds accrued off-chain in these channels to in-turn make tamper-proof off-chain payments to merchants, without locking up corresponding capital in channels with merchants. Our design ensures that new payments made to merchants are guaranteed to be safe once notarized and provably mitigates well-known drawbacks in previous constructions like the data availability attack and ensures that neither consumers nor merchants need to be online to ensure continued safety of their notarized funds. We show that the on-chain monetary and computational costs for PayPlace is O(1) in the number of payment transactions processed, and is near-constant in other parameters in most scenarios. PayPlace can hence scale the payment throughput for large-scale marketplaces at no marginal cost and is orders of magnitude cheaper than the state-of-art solution for non-pairwise off-chain payments, Zero Knowledge Rollups.

Open access
2 source records
cs.CR
cs.NI
Blockchain Technology Applications and Security
Original source
Mar 6, 2020·WI2020 Zentrale Tracks
21 cites
Confidentiality-preserving Validation of Tax Documents on the Blockchain

Filip Fatz, Philip Hake, Peter Fettke

Information exchange between tax administrations, businesses, and auditors is key to effective tax enforcement. Therefore, organizations proposed the application of blockchain technology to interconnect the different actors and increase tax transparency. However, the lack of confidentiality measures hampers further development. Especially, businesses are concerned about the disclosure of commercially sensitive information that might threaten their competitive advantage. In this paper, we investigate how the application of zero-knowledge-proofs can contribute to solving the dilemma between transparency and confidentiality in blockchain-based tax systems. To meet this end, we provide a conceptual design of a confidentiality-preserving distributed tax ledger. Moreover, we present a prototype addressing reporting obligations in the context of value-added tax. Our evaluation shows that zero-knowledge proofs are an effective measure to trade off transparency against confidentiality. Still, their application is challenging and future research must focus on better abstractions of proving statements.

Blockchain Technology Applications and Security
Privacy, Security, and Data Protection
Privacy-Preserving Technologies in Data
Original source
Mar 2, 2020·IEEE Transactions on Vehicular Technology
149 cites
Privacy-Preserving Authentication Scheme for Connected Electric Vehicles Using Blockchain and Zero Knowledge Proofs

David Gabay, Kemal Akkaya, Mumin Cebe

With the increasing interest in connected vehicles along with electrification opportunities, there is an ongoing effort to automate the charging process of electric vehicles (EVs) through their capabilities to communicate with the infrastructure and each other. However, charging EVs takes time and thus in-advance scheduling is needed. As this process is done frequently due to limited mileage per charge on EVs, it may expose the locations and charging pattern of the EV to the service providers, raising privacy concerns for their users. Nevertheless, the EV still needs to be authenticated to charging providers, which means some information will need to be provided anyway. While there have been many studies to address the problem of privacy-preserving authentication for vehicular networks, such solutions will be void if charging payments are made through traditional means. In this paper, we tackle this problem by utilizing distributed applications enabled by Blockchain and smart contracts. We adapt zero-knowledge proofs to Blockchain for enabling privacy-preserving authentication while removing the need for a central authority. We introduce two approaches, one using a token-based mechanism and another utilizing the Pederson Commitment scheme to realize anonymous authentication. We also describe a protocol for the whole process which includes scheduling and charging operations. The evaluation of the proposed approaches indicates that the overhead of this process is affordable to enable real-time charging operations for connected EVs.

Blockchain Technology Applications and Security
Cryptography and Data Security
Vehicular Ad Hoc Networks (VANETs)
Original source
Mar 1, 2020·The Annals of Probability
0 cites
Cutoff for the mean-field zero-range process with bounded monotone rates

Jonathan Hermon, Justin Salez

We consider the zero-range process with arbitrary bounded monotone rates on the complete graph, in the regime where the number of sites diverges while the density of particles per site converges. We determine the asymptotics of the mixing time from any initial configuration, and establish the cutoff phenomenon. The intuitive picture is that the system separates into a slowly evolving solid phase and a quickly relaxing liquid phase: as time passes, the solid phase dissolves into the liquid phase, and the mixing time is essentially the time at which the system becomes completely liquid. Our proof uses the path coupling technique of Bubley and Dyer, and the analysis of a suitable hydrodynamic limit. To the best of our knowledge, even the order of magnitude of the mixing time was unknown, except in the special case of constant rates.

Open access
Stochastic processes and statistical mechanics
Markov Chains and Monte Carlo Methods
Point processes and geometric inequalities
Original source
Mar 1, 2020·網際網路技術學刊
1 cites
Secure Authentication Protocol for Efficient Computational Offloading Service in the Mobile Cloud Computing

E. Munivel, A. Kannammal

Battery-powered mobile devices are convenient to use anywhere and anytime. Nowadays maximum people using the mobile device, such as Smartphone, Tablet computers to use mobile services anytime and anywhere. Moreover, most of the Smartphone having wireless communication like Wi-Fi and 4G. For some applications, the requirement of computing power may be very high, but the actual configuration of mobile devices are very limited, such as CPU, memory, storage, and battery. Among these computational resources, bandwidth and battery are the most significant problems for Smartphone. Efficient Computational Offloading is the best solution for extending the usage of Smartphone by executing the resource-intensive task to offload from mobile to the remote cloud servers can extend processing capability and support for multiple categories of application. However, this technique is having difficulty in offloading the process to a remote cloud server without the proven security of entity verification. To deal with these challenges, here we are proposing new security protocol to authenticate mobile and cloud server with zero knowledge proof of authentication to verify the communication entities and recommends to offload the service. The proposed protocol will get verify by the University of Oxford developed verification tool Scyther.

IoT and Edge/Fog Computing
User Authentication and Security Systems
Advanced Authentication Protocols Security
Original source
Mar 1, 2020·2020 7th International Conference on Computing for Sustainable Global Development (INDIACom)
3 cites
Robust Comparative Analysis of Zero-Knowledge Proofs using Discrete Logarithm Problem

Chitranjan Prasad Sah, Preeti Rani Gupta

Robustness features are essential for any black-box or non-black box security mechanism in cryptography. Zero-knowledge proofs is an example of non-black box security mechanism used in cryptography. In this paper, we have explored and analyzed zero-knowledge proofs using discrete logarithm problem and compared it with integer factoring problem to check its robustness and compatibility for higher security in cryptography. The upper bound of Pollard's rho algorithm for discrete logarithm is growing faster in comparison with Pollard's rho factoring algorithm. The covariance between asymptotic notations of two different algorithms for zero-knowledge proofs are computed and positive covariance result is obtained, which clearly shows that random variants used for both algorithms are growing in same direction and have similar behavior. The functional value line segment of Pollard's rho algorithm for discrete logarithm converges with the functional value line segment of Pollard's rho factoring algorithm at a point.

Cryptography and Data Security
Complexity and Algorithms in Graphs
Cryptography and Residue Arithmetic
Original source
Feb 26, 2020·Neurocomputing
2 cites
Estimating stochastic linear combination of non-linear regressions efficiently and scalably

Di Wang, Xiangyu Guo, Chaowen Guan, Shi Li · 5 authors

Recently, many machine learning and statistical models such as non-linear regressions, the Single Index, Multi-index, Varying Coefficient Index Models and Two-layer Neural Networks can be reduced to or be seen as a special case of a new model which is called the \textit{Stochastic Linear Combination of Non-linear Regressions} model. However, due to the high non-convexity of the problem, there is no previous work study how to estimate the model. In this paper, we provide the first study on how to estimate the model efficiently and scalably. Specifically, we first show that with some mild assumptions, if the variate vector $x$ is multivariate Gaussian, then there is an algorithm whose output vectors have $\ell_2$-norm estimation errors of $O(\sqrt{\frac{p}{n}})$ with high probability, where $p$ is the dimension of $x$ and $n$ is the number of samples. The key idea of the proof is based on an observation motived by the Stein's lemma. Then we extend our result to the case where $x$ is bounded and sub-Gaussian using the zero-bias transformation, which could be seen as a generalization of the classic Stein's lemma. We also show that with some additional assumptions there is an algorithm whose output vectors have $\ell_\infty$-norm estimation errors of $O(\frac{1}{\sqrt{p}}+\sqrt{\frac{p}{n}})$ with high probability. We also provide a concrete example to show that there exists some link function which satisfies the previous assumptions. Finally, for both Gaussian and sub-Gaussian cases we propose a faster sub-sampling based algorithm and show that when the sub-sample sizes are large enough then the estimation errors will not be sacrificed by too much. Experiments for both cases support our theoretical results. To the best of our knowledge, this is the first work that studies and provides theoretical guarantees for the stochastic linear combination of non-linear regressions model.

Open access
2 source records
Statistical Methods and Inference
Markov Chains and Monte Carlo Methods
Statistical Methods and Bayesian Inference
Original source
Feb 20, 2020·Research Explorer (The University of Manchester)
0 cites
Blockchain Applications Beyond the Cryptocurrency Casino: The Punishment not Reward (PnR) Blockchain Architecture

Banach, Richard; id_orcid 0000-0002-0243-9434

The Bitcoin model originated blockchain architectures and inspired their further development. Blockchain architectures are still most commonly associated with currency applications, and with financial speculation. Bitcoin’s rewards for Proof of Work mining became the default consensus technique for blockchains.<br/>As an alternative to reward mechanisms for blockchain maintenance, we propose punishment mechanisms for neglecting to maintain the blockchain (provided participants are intrinsically motivated to be beneficiaries of the blockchain application). Punishment not Reward (PnR) is convincing for enterprise mission critical blockchain applications, and potential punishment mechanisms include denial of service and/or revocation of confidentiality. This obviates the need for reward via cryptocurrencies, along with their attendant volatility, insecure ecosystem and market manipulation demerits. The privacy concerns of competing entities participating in a blockchain application are prima facie in conflict with the needs of the community to be able to inflict punishment mechanisms. Conflicts of this kind can be addressed via sophisticated cryptographic techniques such as secret sharing, multiparty computation, zero-knowledge proofs, etc., which play a vital role. We stress the importance of correctly balancing all application specific interests in the engineering of blockchain applications, so that the mix of incentives and disincentives is stabilising.

Blockchain Technology Applications and Security
Big Data and Digital Economy
Cryptography and Data Security
Original source
Feb 11, 2020·Journal of Computer Science and Its Application
0 cites
Stemming anomaly propagation in software systems using ontology

Tajudeen Adeniji Adetunji, Olusegun Folorunso, Olufunke Rebecca Vincent, Olaniyi Mathew Olayiwola

The increasing use of information and communication technology over the last decade has driven a new range of information needs in business. A number of these software systems in deployment, however, suffer from detrimental unintended integrity and consistency compromise due to anomaly infestation. Primarily, the effects of this usually culminate in unpredictable and catastrophic results, which must be adequately checked to yield highly dependable software. This paper proposes a unified framework for analyzing propagations of anomalies in software systems employing ontology to characterize, categorize, and identify these errors; also, to provide guidelines for the implementation of the proposed solution. The generic approach captures the conventional semantics and structure of different types of anomalies with the notion of anomaly ontology. The prototype Ontology-based Software Anomaly Propagation Detection System (OBSAPDS) was built with the Protégé 4.3 knowledge acquisition tool, and Java programming languagPe was used for the development of the application and MySQL Server as the back en--gine. The combination of the domain ontology in Protégé and inference rules in Jena formed the knowledge system for the elicitation and the validation of domain facts. Besides, a proof-of-concept evaluation of the proposed framework confirmed how efficiently the approach could discover and resolve anomalies for different types of systems through demonstration. The division by zero error and the read access to uninitialized error conditions served as case studies.Keywords: Ontology, software systems, anomaly propagation

Software System Performance and Reliability
Software Engineering Research
Service-Oriented Architecture and Web Services
Original source
Feb 11, 2020·Catheterization and Cardiovascular Interventions
22 cites
SCAI multi‐society position statement on occupational health hazards of the catheterization laboratory: Shifting the paradigm for Healthcare Workers' Protection

Lloyd W. Klein, James A. Goldstein, David E. Haines, Charles E. Chambers · 8 authors

Renewed attention has focused on the occupational health hazards posed by working in the fluoroscopic laboratory.1-6 Accumulated occupational radiation exposure is associated with health risks to physicians, nurses, and technologists working in this environment. Health care workers are subject to insidious health effects of radiation exposure over many years. Adverse effects include the established predilection to posterior subcapsular cataracts, as well as worrisome signals of lifetime risks of cancer induction, particularly in the unprotected brain.7-12 A further consequence is the extensively documented incidence of orthopedic illnesses reported in physicians as well as nurses and technologists and injuries linked to the cumulative burden of bearing the weight of only partly protective lead aprons mandatory to reduce radiation risk.13-16 The increased volume and complexity of procedures, together with the physical stresses inherent in procedural performance, have exacerbated the prevalence and magnitude of such orthopedic injuries.17 The high prevalence of orthopedic afflictions not only affects individual health but also could be potential career ending, with workforce implications for both the profession as well as for society.15 Advances in interventional imaging techniques and treatments over the last three decades have achieved significant success with clear benefits to our patients18; yet protective measures for workers have unfortunately lagged the pace, magnitude, and impact of this therapeutic progress. The purpose of this position statement is to review the data documenting occupational health injuries, summarize current equipment and processes that can be widely applied to optimize protection, emphasize the importance of investment by hospitals and health systems in protective equipment established to enhance workplace safety, examine barriers that need to be overcome to spur advances to enhance the occupational safety of the fluoroscopic laboratory environment, and propose enhanced advocacy for innovation. Future processes and proposals to improve the fluoroscopic laboratory environment should be based on the following precepts: (a) there is ample clinical data documenting the prevalence of serious occupational health risks engendered by the fluoroscopic laboratory environment; (b) sufficient attention to these occupational health issues has been drawn in annual meetings and published clinical scientific studies; (c) despite these data and advocacy efforts, advances to improve worker safety in the fluoroscopic laboratory remain inadequate; and (d) a concerted effort by all stakeholders (physicians, catheterization laboratory nurses, and technologists, sonographers, hospitals, professional societies, and industry) in the fluoroscopic laboratory is necessary to further advance occupational safety and health. Radiation exposure is inherent to procedural performance in the fluoroscopic laboratory. Exposure to ionizing radiation imposes health risks to both patients and operators, resulting in an increased likelihood of numerous illnesses and diseases.1-8 The association with posterior subcapsular cataracts is well documented.11, 12 There are growing concerns for cancer induction,7, 8 with recent reports of a cluster of predominantly left-sided brain cancers in interventionists,9, 10 as well as a signal for increased breast19-22 and skin cancers.23-26 Radiation exposure generally, not necessarily as part of occupational exposure, is associated with leukemia/lymphoma, myeloma, numerous gastrointestinal and bone cancers, and thyroid and parathyroid adenomas. These disquieting signals fuel the increasing anxiety regarding radiation exposure-related oncogenesis, though no mortality impact has been proven.27 Recent studies have also suggested that occupational radiation exposure is associated with hypertension, hypercholesterolemia, and possibly atherosclerosis.28-30 Evidence of lengthening sarcomere length and early vascular aging in epidemiologic studies suggests that workers who are occupationally exposed to radiation during interventional procedures may be at increased risk to develop these same illnesses.30, 31 There is now overwhelming evidence demonstrating that working in the interventional laboratory is associated with an increased incidence of orthopedic illnesses, particularly those related to the cervical and lumbar spine. These orthopedic injuries have been linked to the cumulative effects of bearing the weight of leaded aprons.5, 15, 16 Additionally, the design of the catheterization laboratory environment promotes awkward orthopedic ergonomic postures (e.g., monitors placed out of the line of natural working sight views). As procedures become increasingly complex and prolonged, and their volume increase in number, it should not be surprising that interventional practice is attended by a high rate (40–50%) of occupational-induced orthopedic injuries.15-17 Over a career's duration, the likelihood of suffering such illnesses are 2–7 times27, 28 higher than other medical occupations. Studies report substantial differences in orthopedic injuries between those wearing lead aprons working in the fluoroscopic laboratory compared to colleagues working in the same department not working in the fluoroscopic laboratory and thus not bearing the burden of wearing lead aprons.27-29 These occupational-related injuries not uncommonly result in missed days of work, surgery, and, in some cases, curtailed careers. This issue has significant implications for the interventional workforce, particularly in view of the aging of the population and anticipated increased procedural demand concomitant with aging of the operators who pioneered these advances.17, 27-29 These occupational health concerns potentially affect several medical specialties, including cardiologists, radiologists, and surgeons working with fluoroscopy, as well as pain management specialists performing nonvascular fluoroscopic procedures. Importantly, all such issues also pertain to the other personnel who are essential members of the “interventional team” (e.g., nurses and technologists, interventional imagers, and cardiac anesthesiologists) who are exposed to the harmful effects of scattered ionizing radiation.30-33 Electrophysiologists and their team are also exposed to radiologic risks and orthopedic injury34 and perhaps even more so, given the duration of their procedures and lack of upper torso shielding during device cases (e.g., implantable defibrillators and cardiac resynchronization therapy). These issues also have particular importance to women; although radiation effects on the fetus have not been demonstrated, women report concerns for adverse effects during reproduction as an obstacle to choice of an interventional career. These radiation exposure concerns have sometimes been considered a reason for disproportionately low representation of women in the field.35 As noninvasive cardiologists specialized in imaging are now required to guide interventions in the catheterization and electrophysiology laboratories, pursuing career in imaging is no longer radiation free and a safer choice for women. This may result in shifts in gender distribution in various cardiology subspecialties, further impacting strategies to improve diversity and inclusion in out profession. The past three decades have witnessed astounding progress in interventional equipment, technique, therapeutics, and the clinical research that catalyzed these advances. Progress in interventional laboratory protection and safety has comparatively lagged, despite the growing mounting data emphasizing occupational health concerns. A paradigm shift to dramatically improve the occupational safety for all stakeholders in the fluoroscopic laboratory (members of the interventional team, professional societies, hospitals, and industry) is required. In particular, there is an opportunity and obligation for industry and hospitals, who clearly benefit from the workers' commitment to their profession, to play a leadership role in correcting these deficiencies. A template exists based on the collaboration established by recent FDA-led efforts aimed to reduce patient exposure.36 Leveraging the concept and practice of the “Image Wisely” and “Image Gently” campaigns codified by Radiological Society of North America37 and Pediatric Cardiology community38 to minimize radiation exposure to patients, in 2010, the FDA Center for Devices and Radiological Health launched an Initiative to Reduce Unnecessary Radiation Exposure from Medical Imaging. As part of this initiative, the FDA held a public meeting on ways to improve devices to reduce unnecessary radiation exposure to help the agency decide on any new, targeted requirements for manufacturers of computed tomographic and fluoroscopic devices. This effort resulted in an industry-driven enhanced awareness, with mandates to recognize both the needs for and market potential of innovations focused on minimizing patient radiation exposure. These initiatives rapidly resulted in dramatic changes to improve the X-ray systems. Examples of these improvements include minimizing radiation exposure through lower emission X-ray systems as well as monitoring, recording of each procedure's patient exposure, and standardization in laboratory reports and patient charts. These efforts have also stimulated industry to develop X-ray systems that provide high-quality imaging at low-radiation exposure dose levels. Hospitals should be encouraged to invest in adopting such platforms that have potential to mitigate occupational risk. Physicians working with our professional societies should strive to establish a culture of safety encompassing both patients and catheterization laboratory personnel (Table 1). The pathway forward should be focused to assure: (1) consistent application and adherence to established and procedural processes; (2) widespread adoption and utilization of novel commercially available protection systems; and (3) encouragement and support to further develop even more effective equipment and processes that facilitate enhanced safety and protection in the workspace. Our professional societies must support individual physicians, teams, and practices, especially those that are hospital owned. It is critical that clinician leaders speak authoritatively to hospital administration and industry partners regarding these concerns without fear of reprisal; societal support could be influential in these situations. The following specific steps should be endorsed by our professional societies to enhance hospital and physician compliance: Whether or not to comply with appropriate shielding and other safety measures should not be at the discretion of the operator. The imaging team (physician, sonographer, radiologic technologist, physicist, and other medical personnel) should be responsible for developing optimized protocols, implementing regular equipment quality control tests, and monitoring radiation doses to patients and members of the team. This group and their products should be recognized as an essential part of the quality assurance program, present in all laboratories, for emphasizing radiation management. Operator dose is directly proportional to patient dose; thus, reducing the dose to the patient will benefit the operator. Knowledge of radiation and methods to reduce risk should be stressed to all operators who perform fluoroscopically guided interventions, practiced routinely, and all staff educated in these measures and assuring they are adhered. These methods and concepts have been well described previously.1-7 Recently, publications from the Society of Cardiovascular Angiography and Interventions, The Heart Rhythm Society, and the American College of Cardiology/multi-society consensus document18 articulate detailed procedural systems and processes, as well as practical approaches, to assist cardiac catheterization laboratories in establishing optimal radiation safety program. The components of a radiation safety program include essential personnel, radiation monitoring, protective shielding (at minimum strict adherence to protective aprons and leaded glasses), imaging equipment, and training/education.39-41 Fundamental principles of radiation safety teach the tenet that radiation exposure should be “as low as reasonably achievable (ALARA)”, with monitoring to assure individuals do not exceed annual or lifetime “safe limits.” Unfortunately, the term “reasonably achievable” is ambiguous and not actionable, and may unintentionally inhibit innovative strides to improve safety both for patients who require medically necessary procedures and for workers in radiation-exposed environments. The phrase might incorrectly imply that as long as one's exposure is “minimized,” then that is all that need to be accomplished. Rather, the ultimate goal of innovation efforts should strive to achieve a completely safe environment wherein the ultimate definition of ALARA translates to as close to a zero radiation exposure work environment as possible. Meticulous application of established prudent radiation techniques is obvious and essential. Standard shielding combines laboratory based (e.g., movable ceiling suspended and fixed table-side shielding). Personal protective aprons and eyewear should be properly fitted and maintained, and hospitals should finance these protective devices for all of their employees, including trainees. Newer personal protective choices, including two-piece aprons that are much lighter, may be beneficial; accessory sleeves for arm protection are also available. Despite these advances, the orthopedic burden of only partially protective leaded apparel continues. Institutions and operators must partner to develop a program specific for their laboratory that will result in the adoption of appropriate recent innovations to reduce radiation exposure. Strategies should also include usage of adjunctive devices for which there is substantial data documenting their capability to reduce exposure. Specifically, there is now compelling data demonstrating reductions in exposure with accessory drapes42 (Supplementary Tables); such disposable radiation shielding pads should NOT be refused by hospitals due to their expense. The use of leaded caps has been proposed with mixed results regarding reduction in exposure.43, 44 Simple accessory mobile shields afford significant protection to both nurses and technologists45 as well as to the interventional imaging team.30 More expansive and encompassing lead shielding systems are commercially available,46 and there is a need for more clinical research data supporting their capabilities to reduce exposure. Robotic systems developed to enhance procedural performance also provide protection from radiation exposure to the physician and reduce leaded apron orthopedic burden.47 Thus far, robotics has had limited adoption, due mostly to cost considerations but also fear from the loss of a “hands-on” sensibility. In electrophysiology, intracardiac navigation systems48 have shown efficacy to navigate catheters for ablation procedures with lesser exposure. Simultaneously, industry and physicians must partner to expedite development of a fluoroless catheterization laboratory, using echocardiography, magnetic resonance imaging, 3D mapping, or other technologies. Removing the necessity of lead aprons should be the ultimate goal. Although the proximate cause of many orthopedic complications may be wearing lead, there are other important factors, such as screen height and position, and other ergonometric considerations, which may account for much cervical spine pathology.49 This growing portfolio of enhanced/innovative protective technology will continue to yield a growing pipeline of solutions providing optimism for a healthier work environment. Table 1 summarizes the responsibilities of professional societies going forward. A direct role is a necessity to coordinate the policy matters raised in this document. Table 2 lists the specific future directions recommended for all stakeholders to achieve. It is essential to emphasize that the operator has the responsibility to understand how to use protective equipment optimally to minimize exposure to both patients and personnel.50 Education in this area is already part of cardiology trainee education and is tested in certification exams. Nevertheless, formal training for those who are planning to be interventional operators and imagers should be considered, and compliance monitored on site. Real-time radiation dose monitoring should become standard. Further, physicians must accept the challenge to adopt new technologies for the reduction of occupational hazards. Expense is one reason that new innovations are often not adopted, as it is difficult to advocate for expensive nonrevenue-enhancing equipment in the current fiscal environment. Other obstacles to overcome include potential discomfort with the design modifications and the resistance to making changes in familiar techniques even if there are improvements. The question always arises as to “proof” as to whether the changes are really beneficial, which sometimes become a justification to maintain an unsatisfactory status quo. Therefore, it is incumbent on our profession to continue to produce high-quality clinical research that documents the capabilities of novel imaging equipment, protective devices, and processes designed to improve workplace safety and health. As previously discussed, structural heart interventions depend on procedural image guidance/interventional echocardiography using transthoracic (TTE) or transesophageal echocardiography (TEE) in addition to fluoroscopy. Interventional imagers who operate the TTE or TEE probe and echo console are highly exposed to the harmful effects of scattered ionizing radiation. Protection for these workers also needs to be incorporated and mandated.30, 45, 46 Professional societies should develop programs to assist hospitals and health systems to address occupational safety. It is in everyone's interest to assure the health of medical caregivers.17 The establishment of new, and coordination with existing, comprehensive programs for clinician health in the catheterization and electrophysiology laboratories consistent with recommended wellness programs are an opportunity to highlight this problem. This may include an on-site physical or massage therapist, programs for core strengthening and stretching, and improved posture techniques to prevent orthopedic injury.34 Moreover, this issue can be an opportunity for societies to share and collaborate with international colleagues, who face similar problems. Since the inception of radiologic imaging, the biomedical industry has taken primary responsibility for development and refinement of catheterization laboratory equipment with associated financial benefits. As this equipment engenders intrinsic radiation exposure hazards, industry should assume a level of fiduciary responsibility to optimize the safety of the equipment they design and sell. It is our role to communicate the cardiology community's widespread support for innovations and catheterization laboratory design reformation. Though definite progress has occurred in the past two decades, particularly the advent of high-quality X-ray systems that produce high-quality imaging at lower radiation dose, further innovations are needed to achieve maximal operator radiation protection. The goal is a laboratory design that achieves a completely environment that the need for personal protective apparel and the orthopedic progress has been by the FDA to industry and medical to improve equipment and processes designed to achieve radiation exposure to are that efforts can be to enhance operator safety by providing a template by which this may be innovation will be that market are to such of worker health to increase worker is both the to and a workforce (physicians, nurses, and Hospitals and health care systems should recognize that protective equipment and wellness processes to at the of the health of their workers is more it increased more and increased training Hospitals have the responsibility to and assure worker safety and optimal occupational radiation exposure. radiation provide training and monitoring of personnel and It that hospitals have a responsibility for those working in their and an responsibility not only to maintain and present imaging systems but also to catheterization laboratories with the equipment and established to benefits to the safety and of their of the X-ray with of imaging and equipment are the responsibilities of the will if (e.g., Health and might in on these occupational safety issues and issue that require a for of imaging and protective In this of and commitment on the part of hospitals is critical to industry to invest in research and development of in the that there is an and In our professional societies play a role to help establish is considered and necessary for practice in radiation safety and clinician The is not responsible for the or of any supporting by the than should be to the for the

Open access
Radiation Dose and Imaging
Healthcare cost, quality, practices
Cardiac Imaging and Diagnostics
Original source
Feb 4, 2020·New Generation Computing
51 cites
Physical Zero-Knowledge Proof for Numberlink Puzzle and k Vertex-Disjoint Paths Problem

Suthee Ruangwises, Suthee Ruangwises, 伊東, 利哉, Toshiya Itoh

Numberlink is a logic puzzle with an objective to connect all pairs of cells with the same number by non-crossing paths in a rectangular grid. In this paper, we propose a physical protocol of zero-knowledge proof for Numberlink using a deck of cards, which allows a prover to convince a verifier that he/she knows a solution without revealing it. In particular, the protocol shows how to physically count the number of elements in a list that are equal to a given secret value without revealing that value, the positions of elements in the list that are equal to it, or the value of any other element in the list. Finally, we show that our protocol can be modified to verify a solution of the well-known $k$ vertex-disjoint paths problem, both the undirected and directed settings.

Open access
3 source records
Complexity and Algorithms in Graphs
Cryptography and Data Security
Advanced Graph Theory Research
Original source
Feb 1, 2020·MPG.PuRe (Max Planck Society)
2 cites
MRzero: Fully automated invention of MRI sequences using supervised learning

Alexander Loktyushin, Kai Herz, Nhan Tam Dang, Felix Glang · 10 authors

Purpose: A supervised learning framework is proposed to automatically generate MR sequences and corresponding reconstruction without human knowledge on MR strategies. This enables a target-based optimization from scratch, as well as exploration of novel and flexible MR sequence strategies. Methods: The entire scanning and reconstruction process is simulated end-to-end in terms of RF events, gradient moment events in x and y, and delay times, acting on the input model spin system given in terms of proton density, T1 and T2, and B0. As proof of concept we use both conventional MR images but also binary masks and T1 maps as a target and optimize from scratch using the loss defined by data fidelity, SAR, and scan time. Results: In a first attempt, MRzero learns all gradient and RF events from zero, and is able to generate the aimed at target image. Appending a neural network layer to the reconstruction module also arbitrary targets were learned successfully. Experiments could be translated to image acquisition at a real system (3T Siemens, PRISMA) and could be verified in measurements of phantoms and the human brain in vivo. Discussion/Conclusion: We have developed a fully automated MR sequence generator based on Bloch equation simulations and supervised learning. While we focus on the method herein, having such a differentiable digital MR twin at hand paves the way to a novel way of generating MR sequence and reconstruction solely governed by the target provided, which can be a certain MR contrast, but the possibilities for targets are limitless, e.g. quantification, segmentation, as well as contrasts of other image modalities.

Brain Tumor Detection and Classification
Neural Networks and Applications
Medical Image Segmentation Techniques
Original source
Feb 1, 2020·2020 International Conference on Industry 4.0 Technology (I4Tech)
6 cites
Enhancing the Security and Efficiency of Resource Constraint Devices in IoT

Santosh Pandurang Jadhav, Georgi Balabanov, Vladimir Poulkov, Javed Shaikh

IoT is spreading rapidly from industry to domestic application such as home automation and gathering sensitive data through IoT devices hence the security of these devices and the data transmission is of great importance. Because of the resource constraint devices, lightweight cryptographic protocol plays an important role. Therefore, implementing the zero-knowledge proof along with the hyper elliptic curve cryptography enhances the security and efficiency in the resource constraint devices.

Cryptography and Data Security
Advanced Steganography and Watermarking Techniques
Chaos-based Image/Signal Encryption
Original source
Jan 31, 2020·Zenodo (CERN European Organization for Nuclear Research)
0 cites
A SECURE WEB BASED WATERMARKING SCHEME

Sameer A. Nooh Nidal F. Shilbayeh

Applying watermarking protocols can effectively support the copyright protection to identify illegal distributors over the World Wide Web. Several schemes have been developed for copyright protection of the web based digital contents distributed over the internet. However, these protocols are often needs more complex security actions to be performed by the web based content providers for preserving the integrity of their content. In this paper, we propose a new secure web-based watermarking scheme based on the combination of the security of the public key cryptosystem (PKI) and the watermarking based on threshold cryptography. The proposed watermarking protocol solve the collude problem for the trusted certificate authority (CA) and applies the idea of the zero knowledge proof for verification purposes. Implementation and analysis of the proposed scheme has been conducted.

Open access
Network Security and Intrusion Detection
Original source