Safety-related Devices Research Articles

ID: 203617 One-Year Safety Analysis Using DRG-Stimulation for the Treatment of Lower Limbs CRPS I and II

Dorsal root ganglion stimulation (DRG-S) is effective for the treatment of chronic focal pain conditions1 and superior to traditional spinal cord stimulation (SCS) in the treatment of CRPS types I and II (causalgia).2,3 To provide continued evidence of safety after FDA approval, a post-market, prospective, single-arm, observational study in patients with CRPS types I or II of the lower limbs treated with DRG-S was designed (NCT02800863). The primary goal of the study was to show that the proportion of serious adverse effects (SAEs) in subjects who received a permanent implant was lower than a pre-specified goal of 15.5% after 12 months. SAEs were defined as safety-related device and non-device events that result in the subject's death or a serious deterioration in health that is life-threatening, results in permanent impairment, or requires medical intervention and hospitalization. The study descriptive endpoint was the proportion of subjects with device, procedure, or stimulation-related SAEs (SADE) or AE (ADE)

Evaluation of MCC seismic response according to the frequency contents through the shake table test

Damage to nuclear power plants causes human casualties and environmental disasters. There are electrical facilities that control safety-related devices in nuclear power plants, and seismic performance is required for them. The 2016 Gyeongju earthquake had many high-frequency components. Therefore, there is a high possibility that an earthquake involving many high frequency components will occur in South Korea. As such, it is necessary to examine the safety of nuclear power plants against an earthquake with many high-frequency components. In this study, the shaking table test of electrical facilities was conducted against the design earthquake for nuclear power plants with a large low-frequency components and an earthquake with a large high-frequency components. The response characteristics of the earthquake with a large high-frequency components were identified by deriving the amplification factors of the response through the shaking table test. In addition, safety of electrical facility against the two aforementioned types of earthquakes with different seismic characteristics was confirmed through limit-state seismic tests. The electrical facility that was performed to the shaking table test in this study was a motor control center (MCC).

Modelling of Convolutional Structures Focusing on Error Probability Calculation Via Matlab for Safety-Related Applications

Safety-related communication system SRComS uses a safety code for achieving the integrity of messages transferred between safety-related devices. In most cases, it is a block systematic code that uses syndromic decoding technique. The authors discuss the possibilities of using the convolutional structures for safety-related applications requiring creation of safety case based on quantitative assessment in relation to the transmission integrity level. This assessment is based on code analysis focused mainly on the error probability calculation. The results published in the practical part are obtained using a model created in Matlab environment, in which the chosen convolutional structures were tested. These tests were focused on the transmission error probability analysis provided by a binary symmetric channel, and also on optimization of other parameters affecting the residual error in the decoding algorithm. The results are generalized into concept of methodology for the convolutional codes safety assessment in compliance with standards for safety-related applications.

The Fukushima Nuclear Accident: Insights on the Safety Aspects

The Fukushima nuclear accident has generated doubts and questions which need to be properly understood and addressed. This scientific attitude became necessary to allow the use of the nuclear technology for electricity generation around the world. The nuclear stakeholders are working to obtain these technical answers for the Fukushima questions. We believe that, such challenges will be, certainly, implemented in the next reactor generation, following the technological evolution. The purpose of this work is to perform a critical analysis of the Fukushima nuclear accident, focusing at the common cause failures produced by tsunami, as well as an analysis of the main redundant systems. This work also assesses the mitigative procedures and the subsequent consequences of such actions, which gave results below expectations to avoid the progression of the accident, discussing the concept of sharing of structures, systems and components at multi-unit nuclear power plants, and its eventual inappropriate use in safety-related devices which can compromise the nuclear safety, as well as its consequent impact on the Fukushima accident scenario. The lessons from Fukushima must be better learned, aiming the development of new procedures and new safety systems. Thus, the nuclear technology could reach a higher evolution level in its safety requirements. This knowledge will establish a conceptual milestone in the safety system design, becoming necessary the review of the current acceptance criteria of safety-related systems.

Integration of Physical Units into the Real-time Programming Language PEARL

Physical quantities are only insufficiently mapped into software. Software components, that interpret the same variable with different physical units, bear a risk for human beings, the environment and assets, that depend on the correct functioning of safety-related devices in embedded systems. Programmers can only define atomic types and restrict their range, but physical units like metres or seconds are not attached. This prevents more profound static analyses by compilers, which could detect software errors like physical formulae with false operands or procedure invocations with different units in callers and callees. This paper addresses physical unit checking within the real-time programming language PEARL. Therefore, our contribution is two-fold: On one hand, we define additional PEARL syntax for physical units and implement a static analyser for the procedural variant of PEARL. On the other hand, we define classes for the object-oriented variant of PEARL in order to check the units statically without the need for adapting compilers.

Determination of Error Probability of Cryptography and Safety Codes for Safety-Related Railway Applications

The paper deals with the problem of determination of error probability of cryptography and safety codes used within the safety-related railway applications with increasing safety integrity level (SIL). In the paper are also described requirements for cryptographic block code and safety linear block code in safety-related communications for railway application. The main part is oriented to the description of mathematical apparatus for the error probability of the cryptography and safety block codes for communication between two safety-related devices across GSM-R communication channel. The practical results are related to the quantitative evaluation of an average error probability of the cryptography and safety codes for several lengths of safety-related messages which are expanded about determination of the cryptography degradation with using GMSK modulation scheme.

A Personalized Speech Warning Facilitates Compliance in an Immersive Virtual Environment

The effect of a personalized technology-based warning on compliance was assessed using an immersive virtual environment (IVE). Sixty university students performed an end-of-day routine security check in the IVE. Participants were asked to search for and activate safety-related devices, which involved entering several rooms. Just prior to abandoning the first room, participants were incidentally exposed to a posted warning (mandatory to disconnect the music generator) consisting of either a personal warning (i.e., a speech message with the participant’s first name) or an impersonal warning (i.e., a auditory beep signal). Compliance was determined by observing whether or not the participants pressed the button-switch as directed by the warning. Results reveal that compliance rate was significantly greater when the warning was personalized. No significant gender differences were found. Implications of these results are discussed in terms of the benefits of effective warnings.

Market Data — Sensors in Household Appliances

AbstractIn Europe, the household industry produces millions of washing machines, dishwashers, cookers, refrigerators, home comfort appliances, small appliances, heating and climate control and security and safety‐related devices. Here, the use of sensors and microsystem products has a long tradition regarding relatively simple devices, such as temperature sensors or level sensors. However, the rate of introduction of new and improved sensors in household appliances has now increased, and the use of modern sensors with intelligent control systems is a key for differentiation between different appliance products and companies. Therefore, some more general sensor application areas are described, and also specific sensors which have been developed in recent years. Additionally, an outlook is given for possible new products and features which may be introduced in the future.

Snubber aging assessment

Abstract Snubbers are safety-related devices used to restrain undesirable dynamic loads at various piping and equipment locations in nuclear power plants (NPPs). Each snubber must accommodate a plant's normal thermal movements and be capable of restraining the maximum off-normal dynamic loads postulated for its specific location. The effects of snubber aging and the environments and mechanisms that degrade snubber performance need to be better understood. This paper describes the Phase II Nuclear Plant Aging Research Program in-plant aging research conducted to enhance the understanding of snubber aging and its consequences. Pacific Northwest Laboratory staff and their subcontractors, Lake Engineering and Wyle Laboratories, visited eight sites (encompassing thirteen plants) to conduct interviews with NPP staff and to collect snubber aging, testing, and maintenance data. The research methodology, evaluations, results, conclusions, and recommendations are described in the paper. Effective methods for service-life monitoring of snubbers are included in the recommendations.