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In the present paper practical recommendations for selection of a surge protective devices (SPD) system with aim to protect electronic and electrical apparatus within a structure against overvoltages coming from the low-voltage power lines are highlighted. The investigation is performed with two standardized lightning currents, namely 200 kA wave shape 10/350 μs for first positive stroke and 50 kA wave shape 0.25/100 μs for subsequent stroke of negative flashes. The analyses are performed by computer simulations at the referring typical basic arrangement consisting of ten poles overhead line terminated on one side by HV/LV transformer and on other side by apparatus to be protected. The results are obtained by means of commercial transient software EMTP-RV. This work is executed in the frame of discussion on recommendation of IEC/EN 62305 [1] for the selection of coordinated SPD system. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the suitability of capillary blood obtained by a minimally invasive lancet technique to detect subclinical ketosis in 49 prepartum and 191 postpartum Holstein-Friesian cows using 3 different electronic hand-held devices [FreeStyle Precision (FSP, Abbott), GlucoMen LX Plus (GLX, A. Menarini), NovaVet (NOV, Nova Biomedical)]. The β-hydroxybutyrate (BHBA) concentration in serum harvested from coccygeal blood samples was analyzed in a laboratory and used as a reference value. Capillary samples were obtained from the skin of the exterior vulva by using 1 of 3 different lancets. In all samples, the concentration of BHBA was immediately analyzed with all 3 hand-held devices used in random order. All lancets used in the study were eligible for capillary blood collection but differed in the total number of incisions needed. Spearman correlation coefficients between the BHBA concentrations in capillary blood and the reference test were highly significant with 83% for the FSP, 73% for the NOV, and 63% for the GLX. Using capillary blood, the FSP overestimated the mean BHBA concentration compared with the reference test (+0.08 mmol/L), whereas the GLX and NOV underestimated the mean concentration (-0.07 and -0.01 mmol/L). When a BHBA concentration of 1.2 mmol/L in serum was used to define subclinical ketosis, the corresponding analyses of receiver operating characteristics resulted in optimized thresholds for capillary blood of 1.1 mmol/L for the NOV and GLX devices, and of 1.0 mmol/L for the FSP. Based on these thresholds, sensitivities (Se) and specificities (Sp) were 89 and 84% for the NOV, 80 and 89% for the GLX, and 100 and 76% for the FSP. Based on a serum BHBA concentration of 1.4 mmol/L, analyses of receiver operating characteristics resulted in optimized cut-offs of 1.4 mmol/L for the FSP (Se 100%, Sp 92%), 1.3 mmol/L for the NOV (Se 80%, Sp 95%), and 1.1 mmol/L (Se 90%, Sp 85%) for the GLX. Using these optimized thresholds for the specific hand-held meters, no significant differences between the devices in Se and Sp to detect subclinical ketosis in coccygeal blood were observed. Calculated test characteristics for analyzing capillary blood using the hand-held devices were numerically smaller compared with blood obtained from a coccygeal vessel, but overlapping confidence intervals indicate no statistical difference between the origin of the sample. Hence, this procedure seems to be suitable for ketosis monitoring in dairy cows, but further validation with more data from different farms is recommended. [ABSTRACT FROM AUTHOR]

The time-dependent stock of PBDEs contained in in-use products (excluding building materials and large vehicles) was estimated for the U.S. and Canada from 1970 to 2020 based on product consumption patterns, PBDE contents, and product lifespan. The stocks of penta- and octaBDE peaked in in-use products at 17?000 (95% confidence interval: 6000-70 000) and 4000 (1000-50 000) tonnes in 2004, respectively, and for decaBDE at 140 000 (40?000-300 000) tonnes in 2008. Products dominating PBDE usage were polyurethane foam used in furniture (65% of pentaBDE), casings of electrical and electronic equipment or EEE (80% of octaBDE), and EEE and automotive seating (35% of decaBDE for each category). The largest flow of PBDEs in products, excluding automotive sector, to the waste phase occurred between 2005 and 2008 at ~10 000 tonnes per year. Total consumption of penta-, octa-, and decaBDE from 1970 to 2020 in products considered was estimated at ~46 000, ~25 000, and ~380 000 tonnes, respectively. Per capita usage was estimated at 10-250, 10-150, and 200-2000 g∙capita-1∙y-1 for penta-, octa-, and decaBDE, respectively, over the time span. Considering only the first use (no reuse and/or storage) of PBDE-containing products, approximately 60% of the stock of PBDEs in 2014 or ~70 000 tonnes, of which 95% is decaBDE, will remain in the use phase in 2020. Total emissions to air of all PBDEs from the in-use product stock was estimated at 70-700 tonnes between 1970 and 2020, with annual emissions of 0.4-4 tonnes∙y-1 for each of penta- and octaBDE and 0.35-3.5 tonnes∙y-1 for decaBDE in 2014. [ABSTRACT FROM AUTHOR]

Abstract: The new international standard for communication networks and systems in substations, IEC61850, is expected to involve a profound evolution in electrical power systems. The new functionalities supported by an intelligent application of IEC61850 must result in a significant improvement of stability and reliability of power systems. Protection systems play a leading role in power system stability and reliability, since those depend on correct, rapid and selective disturbances elimination. A new protection scheme, performed by new intelligent electronic devices (IEDs) based on the new features brought by IEC61850, is presented in this paper. The implementation of the proposed scheme involves important cost reductions, at the same time that the protective redundancy of the system is improved. [Copyright &y& Elsevier]

transparent device is an electromagnetic structure that is explicitly designed to be transparent to incoming electromagnetic waves. Based on coordinate transformation theory, a novel diamond-shaped transparent device is proposed and designed. It can protect electronic equipments inside without affecting their performance. Compared with a traditional transparent device, the material parameters of the novel transparent device feature homogeneity and non-singularity, which can easily be realized in actual applications. Full-wave simulations are made to validate the performance of the transparent device. [ABSTRACT FROM AUTHOR]

This paper presents a comparison between the types of protection for electrical apparatus by comparing some common characteristics that are important for maintaining the integrity of explosion protection. [ABSTRACT FROM AUTHOR]

Abstract: Since digital technologies have been improved, the analog systems in nuclear power plants (NPPs) have been replaced with digital systems. Recently, new NPPs have adapted various kinds of digital instrumentation and control (I&C) systems. Even though digital I&C systems have various fault-tolerant techniques for enhancing the system availability and safety compared to conventional analog I&C systems, the effects of these fault-tolerant techniques on system safety have not been properly considered yet in most probabilistic safety assessment models. Therefore, it is necessary to develop the safety evaluation method for digital I&C systems with consideration of fault-tolerant techniques. Among the various issues in the safety model for digital I&C systems, one of the important issues is how to exclude the duplicated effect of fault-tolerant techniques implemented at each hierarchy level of the system. The exact relation between faults and fault-tolerant techniques should be identified in order to exclude this duplicated effect. In this work, the relation between faults and fault-tolerant techniques are identified using fault injection experiments. As an application, the proposed method was applied to a module of a digital reactor protection system. [ABSTRACT FROM AUTHOR]

Abstract: The CDM failure threshold of microelectronic components are determined by the peak value of the discharge current. The requirements of the market, however, are given in terms of potential. In addition, it is not known how the CDM susceptibility of an IC is affected by its core circuitry. This paper introduces an idea how CDM protection concepts can be checked by tests on an interface test chip to guarantee satisfying product qualifications. [Copyright &y& Elsevier]

Abstract: The electromagnetic interference has many undesired effects to the office equipments and the performance of technological devices. Therefore, electrical devices should have field protection mechanism against magnetic fields. The shielding mechanism prevents external magnetic field emitted from the device to the vicinity area. This work attempts to apply artificial neural network in order to estimate shielded magnetic field for multilayer shielding application. The multilayer magnetic shielding performances of cylindrical shaped ferromagnetic shields under extremely low frequency are investigated. For this purpose, three different ferromagnetic materials in cylindrical shape are chosen for magnetic shielding. The shielding performances of these materials are measured and a selected set of data is used to train and test an artificial neural network. The proposed neural network model achieves an intelligent decision for the shielded magnetic field level based on distance, unshielded magnetic field value, number of shield layer and skin-depth of the shield. [Copyright &y& Elsevier]

Abstract: The radiation protection materials for electronic devices in strategic nuclear weapon are demanded to have some characteristics: higher specific strength and modulus, and anti-radiation property. Therefore, a novel BaPbO3/Al composite was fabricated by powder metallurgy for the first time. The microstructure of the composite was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The tensile test and photon shielding test were performed to determine the mechanical properties and radiation protection function of the composite, respectively. The experimental results shows that the composite has a similar density as aluminum, meanwhile, it exhibits excellent anti-radiation properties and improved tensile strength and elastic modulus compared with aluminum. Thus, it is promising for application as a novel radiation protection material. [Copyright &y& Elsevier]

Considering gate-oxide reliability, a new electrostatic discharge (ESD) protection scheme with an on-chip ESD bus (ESD_BUS) and a high-voltage-tolerant ESD clamp circuit for 1.2/2.5 V mixed-voltage I/O interfaces is proposed. The devices used in the high-voltage-tolerant ESD clamp circuit are all 1.2 V low-voltage N- and P-type MOS devices that can be safely operated under the 2.5-V bias conditions without suffering from the gate-oxide reliability issue. The four-mode (positive-to-VSS, negative-to-VSS, positive-to-VDD, and negative-to.VDD) ESD stresses on the mixed-voltage 110 pad and pin-to-pin ESD stresses can be effectively discharged by the proposed ESD protection scheme. The experimental results verified in a 0.13-μm CMOS process have confirmed that the proposed new ESD protection scheme has high human-body model (HBM) and machine-model (MM) ESD robustness with a fast turn-on speed. The proposed new ESD protection scheme, which is designed with only low-voltage devices, is an excellent and cost-efficient solution to protect mixed-voltage I/O interfaces. [ABSTRACT FROM AUTHOR]

The development of protection circuits against a variety of electromagnetic disturbances is important to assure the immunity to interferences of an electronic system. In this paper protection elements which were investigated under UWB conditions are now to be tested with HPM signals to achieve a comprehensive protection. [ABSTRACT FROM AUTHOR]

A system-level thermal modeling methodology for shipboard power-electronics cabinets is presented and demonstrated for a PCM-1 cabinet, a complex air-to-water-cooled cabinet design of interest to naval applications. The cabinet is completely sealed and the heat dissipation in the power electronics bays is removed from the cabinet by re-circulating the hot air through an air-to-water-cooled packaged heat exchanger that is served by an external fresh water loop. A detailed unit-wise analytical model is developed for the packaged heat exchanger used in the cabinet. Under the prescribed design parameters, the PCM-1 cabinet operating-point air circulation rate was established to be 0.434 m3/s (920 CFM). A compact model is developed for the air convection within the cabinet using 3-D Computational Fluid Dynamics/Heat Transfer (CFD/HT) simulations in conjunction with Proper Orthogonal Decomposition (POD)-based reduced order modeling techniques. The compact model runs about 350 times faster with a mean prediction error within 3.6% for the velocity field, 0.04% for the temperature field, and 0.15% for the pressure field. The resulting overall cabinet model can be integrated into a system-level modeling platform to simulate the thermal response of multiple cabinets. The CFD/HT simulations of the PCM-1 cabinet architecture suggest that its two uppermost bays would experience high air temperatures due to insufficient local air flow. [ABSTRACT FROM AUTHOR]

A feasibility study of an innovative cooling technique for thermal management of outdoor electronic equipment enclosures is conducted. This technique is based on forced air cooling through the electronic enclosure which is mounted outdoors on top of a sealed hollow pole (Geopole) through which the air is circulated in a closed loop. This Geopole™ cooling technique features several potential advantages over existing techniques for cooling outdoor electronic enclosures. Because the pole is sealed from rain, dust, insects, and other contaminants, the air can be circulated in direct contact through sensitive electronic components such that internal forced convection can be used which eliminates the need for large (heavy) heat sinks on the outer surfaces of the enclosure leading to a significant reduction in weight of the enclosure. Another advantage is the location of the fan close to ground level which facilitates maintenance. A detailed thermal model of the Geopole is developed and parametric studies are conducted to evaluate the effects of important design parameters on thermal performance. The results obtained demonstrate that the Geopole technique is very promising as a cooling technique for outdoor electronic enclosures. These results provide a strong impetus for conducting further studies leading to design improvement of the Geopole technique for enhanced thermal performance. [ABSTRACT FROM AUTHOR]

The electronic equipment for data processing and reading designed for the vertex detector of the SVD-2 setup is described. The structure of basic modules, their characteristics, and software for data acquisition are considered. [ABSTRACT FROM AUTHOR]

Electronic equipment developed for reading, shaping, and recording signals from microstrip sensors of the vertex detector of the SVD-2 setup is described. The configuration of the vertex detector sensors, construction of signal-reading cards, and structure and functions of the recording modules are considered. The obtained characteristics are analyzed. [ABSTRACT FROM AUTHOR]

An improved subcell model is presented for including thin material sheets method in the finite-difference time-domain (FDTD) method. This improved subcell can be used to simulate a thin magnetic (μs ≠ μo) sheet. Then, the improved subcell model is applied to the analysis of the shielding effectiveness (SE) of the electromagnetic wave propagating through a thin infinite material sheet, which is verified by comparison with the analytical results. Updated equations for components of the field on special spatial grids which are on edges and corners of the enclosure are presented, and the subcell model is used for the analysis of a thin-walled enclosure with an aperture. The FDTD results are in very good agreement with the test results. [ABSTRACT FROM AUTHOR]

Three types of walls, which can be used for shielding enclosures, are studied. These three types of walls are single-layer metal, two-layer metal and metal layer coated by a lossy dielectric layer. The properties of these types of walls and their effects on the performance of shielding enclosures are discussed. [ABSTRACT FROM AUTHOR]

The article predicts gap in quad flap package (QFP) with unattached heat spreader. Due to cost and process considerations, sometimes the heat spreader of a QFP is not attached to the die pad. Consequently, due to mismatch of thermal expansions of the components, gapping is inevitable on the unattached interface during temperature change. Presence of the gap would potentially decrease the reliability and thermal performance of QFP. QFP is a popular packaging choice in the electronic packaging industry for its great number of interconnects, thin profile, good electrical characteristics, and low cost.

Workable special protection methods to prevent lightning damage to equipment and possible harm to associated working personnel are presented. This document covers protection methods for ground potential rise, isolation, shielding, and grounding from lightning. Be warned: Protecting a structure from lightning does very little to protect the equipment within that structure, and the housed equipment is normally worth many times the value of the structure. Lightning damage to equipment results in losses exceeding twenty-six billion dollars annually in North America and nearly three times that worldwide, with more than 150 strikes per second. Insurance payout resulting from lightning damage accounts for approximately 6.5% of all property and casualty claims. Ironically, nearly all lightning damage to equipment can be prevented. [ABSTRACT FROM AUTHOR]

Examines methods for making small the so-called transfer impedance which gives interference voltages across a sensitive input per ampere lightning current affecting the protection of sensitive electronics against lightning. Dangers posed by lightning to electronics; Description of protective grounding structures; Example of protection through modification of cabling.

Carbon fibers released from accidental aircraft fires may present a hazard to electronic equipment within a large radius. Two separate methodologies to quantify the associated economic risks were developed and applied, each providing a useful general approach to probabilistic risk assessment. For the case of commercial our carrier accidents, which are infrequent but may release large amounts of carbon fiber, a Monte Carlo simulation was performed for 26 major airports and then the results were aggregated into a national risk profile. For the case of general aviation accidents, which are frequent but release only small amounts, an analytic approach based on the Poisson process was used to estimate the risk profile. The results indicated that the potential economic losses due to carbon fiber usage in civilian aircraft were relatively low [ABSTRACT FROM AUTHOR]