Composite Storage Systems for Compressed Hydrogen - Systematic Improvement of Regulations for More Attractive Storage Units

As future infrastructures increasingly rely on digital systems, their exposure to cyber threats has grown significantly. The complex and hyper-connected nature of these systems presents challenges for enhancing cyber resilience against adverse conditions, stresses, attacks, or compromises on cybersecurity resources. Integrating risk assessment with cyber resilience allows for adaptive approaches that can effectively safeguard critical infrastructures (CIs) against evolving cyber risks. However, the wide range of methods, frameworks, and standards—some overlapping and others inadequately addressed in the literature—complicates the selection of an appropriate approach to cyber risk assessment for cyber resilience. To investigate this integration, this study conducts a systematic literature review (SLR) of relevant methodologies, standards, and regulations. After conducting the initial screening of 173 publications on risk assessment and cyber resilience, 40 papers were included for thorough review. The findings highlight risk assessment methods, standards, and guidelines used for cyber resilience and provide an overview of relevant regulations that strengthen cyber resilience through risk assessment practices. The results of this paper will offer cybersecurity researchers and decision-makers an illuminated understanding of how risk assessment enhances cyber resilience by extracting risk assessment best practices in the literature supported by relevant standards and regulations.

Values of electron mass scattering power, T/p, for various materials have been calculated by using the EGS4 Monte Carlo system and by integration of the Molière multiple-scattering distribution. The energy range covered is 0.5-100 MeV. Monte Carlo calculations test the concept of T/p "experimentally" and assess the contribution to electron mass scattering power from effects such as Moller scatter and energy-loss straggling. The Monte Carlo results agree within 2% with the analytical results calculated from Molière multiple-scattering theory at energies less than 20 MeV for high-Z materials and for energies less than 50 MeV for low-Z materials. At higher energies the Monte Carlo calculations include the effects of bremsstrahlung production which can significantly increase values of T/p. For low-Z materials and electron energies less than 60 MeV, the Monte Carlo calculated T/p values are generally 22% higher than those given by ICRU Report 35, while those for high-Z materials and energies less than 25 MeV are found to be consistent (within 1%) with ICRU Report 35. The effects of Moller scatter, which significantly affect T/p for low-Z materials, as well as bremsstrahlung effects, are included in the present Monte Carlo calculations. If the tabulated T/p data of ICRU Report 35 are modified to include the Moller scatter effect, then for energies less than 60 MeV they are generally 6% less than the present Monte Carlo data for low-Z materials as well as for copper. It is shown that T/p is a well-defined constant over an appropriate range of slab thickness except when bremsstrahlung effects are significant. It is found that T/p is proportional to E-n, where n is in the range of 1.5-2.0 for the energies considered here. The Monte Carlo calculations are shown to agree well with various relevant experimental measurements. Accurate T/p data, which should include the effect of Moller scatter, are necessary in electron-beam treatment planning, especially for a small field size. The choice of the depth step in the implementation of pencil-beam codes should not violate the slab-thickness limits for T/p data.

The Fukushima Nuclear Accident has attracted social public attention to the severe accident. The instruments used to monitor the processing of severe accident could perform the function correctly in the time frame required during and after the Severe Accident Management Guidance (SAMG). International and domestic regulations and standards are all required these instruments available during severe accident. However, it’s still not set down relevant standard that how to analyze the instrument survivability assessment and qualify these instruments. This paper introduces the requirements of relevant regulations and standards, factors, methods of instrument survivability assessment and technology status of instrument survivability assessment. On the basis of assessment method of second-generation plus nuclear power plants, the assessment method of HPR1000 was studied and confirmed. It is improved and optimized on environment, qualification requirement, etc.

The aim of this study was to verify the advanced inhomogeneous dose distribution produced by a volumetric arc therapy technique (RapidArc™) using 3D gel measurements and Monte Carlo (MC) simulations. The TPS (treatment planning system)-calculated dose distribution was compared with gel measurements and MC simulations, thus investigating any discrepancy between the planned dose delivery and the actual delivery. Additionally, the reproducibility of the delivery was investigated using repeated gel measurements. A prostate treatment plan was delivered to a 1.3 liter nPAG gel phantom using one single arc rotation and a target dose of 3.3 Gy. Magnetic resonance imaging of the gel was carried out using a 1.5 T scanner. The MC dose distributions were calculated using the VIMC-Arc code. The relative absorbed dose differences were calculated voxel-by-voxel, within the volume enclosed by the 90% isodose surface (VOI90), for the TPS versus gel and TPS versus MC. The differences between the verification methods, MC versus gel, and between two repeated gel measurements were investigated in the same way. For all volume comparisons, the mean value was within 1% and the standard deviation of the differences was within 2.5% (1SD). A 3D gamma analysis between the dose matrices were carried out using gamma criteria 3%/3 mm and 5%/5 mm (% dose difference and mm distance to agreement) within the volume enclosed by the 50% isodose surface (VOI50) and the 90% isodose surface (VOI90), respectively. All comparisons resulted in very high pass rates. More than 95% of the TPS points were within 3%/3 mm of both the gel measurement and MC simulation, both inside VOI50 and VOI90. Additionally, the repeated gel measurements showed excellent consistency, indicating reproducible delivery. Using MC simulations and gel measurements, this verification study successfully demonstrated that the RapidArc™ plan was both accurately calculated and delivered as planned.

In this paper, a comparative study is made on the test items and evaluation criteria stipulated in the relevant regulations and standards of hydrogen storage system valves and temperature-driven pressure relief devices (TPRD) for hydrogen fuel cell vehicle (HFCV). The similarities and differences are listed and analyzed. Based on the study and according to the characteristics of the assembly valve for HFCV (hereinafter referred to as the assembly valve), some suggestions on the test items, test methods and evaluation criteria settings for the assembly valve are discussed and the test strategy for assembly valve is proposed.

Safety assessment of unignited hydrogen discharge from onboard storage in garages with low levels of natural ventilation

In order to be attractive in a very competitive market, hybrid electric buses and full electric buses need to reduce the total cost of ownership (TCO) compared to conventional buses. In this regard, the sizing of the onboard energy storage and the charging infrastructure becomes a key design stage. An optimal onboard storage and charging facilities are necessary to offer an appropriate vehicle autonomy, but they involve high investment costs for the manufacturer and fleet operator. Furthermore, the complex interrelations between these parameters make the best-performed system design a challenging process. To face this issue, the paper proposes an optimization methodology for the onboard storage capacity sizing, charging points rate and charging points location, aiming a total cost of ownership improvement for hybrid and full electric bus routes. As case study, several routes have been selected in the city of Donostia (Spain) to techno-economically evaluate the proposed methodology regarding factors such as: onboard storage cost, charging infrastructure cost, fuel cost, and electricity-grid cost.

Risk assessment methodology for onboard hydrogen storage

Introduction: 192Ir is one of the important sources frequently used in brachytherapy. Up to now, a lot of commercial models of this source have been made which Ir-192 has been recently added to them. The aim of the present study is to determine the dosimetric parameters of this new source model based on the recommendations of TG-43(U1) protocol using Monte Carlo simulation technique. Materials and Methods: The assessed parameters included dose rate constant, radial dose function, anisotropy function, and dose distribution around the source. Calculations were performed in water phantom using MCNP4C Monte Carlo code. Results: The dose rate constant of this new source in water was 1.07+0.06 cGyh-1U-1 which was in a good agreement with the TLD measured data (1.13+0.07 cGyh- 1U-1). Conclusion: The results of this study showed that the dosimetric characteristics of this new brachytherapy source are comparable with those of other commercially available sources. Furthermore, the simulated parameters were in accordance with the previously measured ones. This means that the Monte Carlo simulated dosimetric parameters could be employed to obtain the dose distribution around this new brachytherapy source based on TG-43(U1) protocol.

Qualitative study on the control of hazardous energy on machinery using lockout and alternative methods

At present, the economy is dominated by carbon (coal, gasoline, petroleum) for generation of electricity and transport. These sections account for almost 56% of greenhouse emissions and contribute towards global warming. This realization that carbon dioxide leads to general increase in global temperatures was released from 1966 to the present day. Current awareness among the members of the general public policy makers and industrial captains has started a dialogue on transitioning from predominately carbon economy to hydrogen or electron (batteries) economy. This can be realized initially in the transport sector (26% of CO2 emissions). The key problem is generation of sustainable hydrogen with zero or lower CO2 emissions than current practice, which is geared towards industrial processes. A log fold increase in hydrogen production would be required from a diverse pool both fossil and renewable sources. Examples discussed include hydrogen production from biomass (glucose economy) through steam reformation (shown in Eq. 10.1), partial oxidation of hydrocarbon (Eq. 10.2), pyrolysis (Eq. 10.3), microbial (Eq. 10.4), and electrolysis (Eqs. 10.5a, 10.5b, and 10.5c). $$ 2{\mathrm{C}}_x{\mathrm{H}}_y + 2 x{\mathrm{H}}_2\mathrm{O} \left(\mathrm{g}\right) 2 x\mathrm{C}\mathrm{O} + \left(2 x+ y\right){\mathrm{H}}_2\left(\mathrm{g}\right) $$ (10.1) $$ 2{\mathrm{C}}_x{\mathrm{H}}_y + x{\mathrm{O}}_2 \left(\mathrm{g}\right) 2 x\mathrm{C}\mathrm{O} + y{\mathrm{H}}_2\left(\mathrm{g}\right) $$ (10.2) $$ 2{\mathrm{C}}_x{\mathrm{H}}_y + 2 x\mathrm{C}+ y{\mathrm{H}}_2 \left(\mathrm{g}\right)\to \mathrm{hydrocarbon} $$ (10.3) $$ 2{\mathrm{H}}^{+} \left(\mathrm{aq}\right) + 2{e}^{-}\to {\mathrm{H}}_2\left(\mathrm{g}\right) $$ (10.4) $$ \mathrm{Anode} \mathrm{reaction}: 4{\mathrm{O}\mathrm{H}}^{-}\left(\mathrm{aq}\right) + 4{e}^{-}\to {\mathrm{O}}_2\left(\mathrm{g}\right)+2{\mathrm{H}}_2\mathrm{O}(l) $$ (10.5a) $$ \mathrm{Cathode} \mathrm{reaction}: 2{\mathrm{H}}_2\mathrm{O}(l) + \to {\mathrm{H}}_2\left(\mathrm{g}\right)+2{\mathrm{OH}}^{-}\left(\mathrm{aq}\right)+4{e}^{-}\left(\mathrm{g}\right) $$ (10.5b) $$ \mathrm{Overall} \mathrm{reaction}: 2{\mathrm{H}}_2\mathrm{O}(l)\to 2{\mathrm{H}}_2\left(\mathrm{g}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right) $$ (10.5c) The above processes could generate sufficient hydrogen to meet the needs of the transport sector, with hydrogen used as a fuel. Examples of hydrogen usage in this manner include: fuel cell powered automobiles either as hybrid (fuel cell – lithium ion batteries), plug-ins (Li-ion battery or hydrogen fuel cell vehicle with on-board storage. The function of the fuel cells such as proton exchange membrane fuel cells is to convert chemical energy to electrical energy spontaneously during electrochemical reactions (Eqs. 10.6a and 10.6b): $$ \mathrm{Anode} \left(\mathrm{hydrogen} \mathrm{oxidation} \mathrm{reaction}, HOR\right): 2{\mathrm{H}}_2\left(\mathrm{g}\right)\to 4{\mathrm{H}}^{+}+4{e}^{-} $$ (10.6a) $$ \mathrm{Cathode} \left(\mathrm{oxygen} \mathrm{reducion} \mathrm{reaction}, ORR\right): 2{\mathrm{O}}_2\left(\mathrm{g}\right)+4{\mathrm{H}}^{+}+4{e}^{-}\to 4{\mathrm{H}}_2\mathrm{O}(l) $$ (10.6b) While no single technology appears to be superior in all aspects, steam reformation and biomass gasification offer practical approaches to generate sufficient hydrogen to meet transportation needs in the near term. The steam reformation of natural gas coupled with CO2 capture can offer a sustainable method, while gasification of biomass using supercritical chromatograph with catalyst offers another approach to generate sustainable hydrogen. In the mid-term, the electrolysis of water using off-peak grid electricity offers a pathway to generate hydrogen with negligible greenhouse emission. In the long term, the biogeneration of hydrogen and splitting of water using photo electrolysis or thermochemical pyrolysis are feasible avenues. The development of these technologies also needs policy makers to create a favorable legislature environment such as tax incentives for end-user or product generator and wider disseminations on the need to transition away from carbon, particularly for nations that do not have a native supply of coal, or petroleum.

Submonolayer epitaxial growth is obtained by the deposition of less than a complete layer of atoms on a single crystal surface. It is of fundamental interest for industrial applications (e.g. in the semiconductor industry) as well as from the point of view of basic research. For example, it is known that nanometer-sized atomic structures (nanostructures) exhibit remarkable physical and chemical properties which can differ greatly from those of bulk matter. In order to investigate these properties, it is often necessary to create large quantities of well defined and possibly spatially ordered nanostructures. One way to achieve this result is self-organized growth where one deposits atoms on a clean crystalline surface and lets the growth process evolve freely. Here, nanostructures result from the atomic diffusion and aggregation processes taking place at the surface. Understanding the exact nature of these processes is of ongoing interest in the field of nanostructure growth. In this thesis we report about submonolayer growth experiments of the ferromagnetic transition metal cobalt. Cobalt was chosen because it exhibits remarkable magnetic properties. These experiments were performed in an ultra-high vacuum chamber and molecular beam epitaxy was used to grow the nanostructures. Observations of the surface were made using a variable-temperature scanning tunneling microscope (STM). In order to get a better understanding of the atomic processes happening at the surface, we developed two adapted computational simulation methods. Kinetic Monte-Carlo (KMC) simulations were used to get an atomistic picture of the surface while mean field rate equations were integrated numerically to yield cluster densities. We study the growth of cobalt on three different surfaces. By depositing Co on a clean Pt(111) crystal surface, we observe that the platinum surface reconstructs by forming star-shaped partial dislocations for sample temperatures above 180 K (-93°C). We also observe that island densities deviate from predictions of all known models towards higher values for these same temperatures. By simulation we are able to show that insertion of Co into the topmost platinum layer creates a repulsive network of dislocations. We show that these dislocations act as diffusion inhibiting barriers and thus influence the island density by constraining the free movement of atoms at the surface. We also show that the Co dimer and trimer diffuse on Pt(111) before dissociating and are able to extract corresponding activation barriers. We also study the deposition of Co on a Ru(0001) surface which shows a more conventional temperature dependence. By comparing simulation and experiment we extract all relevant diffusion activation barriers and show that at high temperatures the Co dimer and trimer dissociate. Finally, we investigate the growth of Co on the hexagonal boron nitride superlattice which forms on a Rh(111) surface. On this surface Co clusters form three-dimensional hemispherical dots. We show how the substrate corrugation influences diffusion of Co atoms and that clusters up to the size of the pentamer can diffuse. By simulation, we also extract the relevant migrations and desorption barriers.

The goal of this study was to investigate small field output factors (OFs) for flattening filter‐free (FFF) beams on a dedicated stereotactic linear accelerator‐based system. From this data, the collimator exchange effect was quantified, and detector‐specific correction factors were generated. Output factors for 16 jaw‐collimated small fields (from 0.5 to 2 cm) were measured using five different detectors including an ion chamber (CC01), a stereotactic field diode (SFD), a diode detector (Edge), Gafchromic film (EBT3), and a plastic scintillator detector (PSD, W1). Chamber, diodes, and PSD measurements were performed in a Wellhofer water tank, while films were irradiated in solid water at 100 cm source‐to‐surface distance and 10 cm depth. The collimator exchange effect was quantified for rectangular fields. Monte Carlo (MC) simulations of the measured configurations were also performed using the EGSnrc/DOSXYZnrc code. Output factors measured by the PSD and verified against film and MC calculations were chosen as the benchmark measurements. Compared with plastic scintillator detector (PSD), the small volume ion chamber (CC01) underestimated output factors by an average of ‐1.0%±4.9%(max.=‐11.7% for 0.5×0.5cm2 square field). The stereotactic diode (SFD) overestimated output factors by 2.5%±0.4%(max.=3.3% for 0.5×1cm2 rectangular field). The other diode detector (Edge) also overestimated the OFs by an average of 4.2%±0.9%(max.=6.0% for 1×1cm2 square field). Gafchromic film (EBT3) measurements and MC calculations agreed with the scintillator detector measurements within 0.6%±1.8% and 1.2%±1.5%, respectively. Across all the X and Y jaw combinations, the average collimator exchange effect was computed: 1.4%±1.1% (CC01), 5.8%±5.4% (SFD), 5.1%±4.8% (Edge diode), 3.5%±5.0% (Monte Carlo), 3.8%±4.7% (film), and 5.5%±5.1% (PSD). Small field detectors should be used with caution with a clear understanding of their behaviors, especially for FFF beams and small, elongated fields. The scintillator detector exhibited good agreement against Gafchromic film measurements and MC simulations over the range of field sizes studied. The collimator exchange effect was found to be important at these small field sizes. Detector‐specific correction factors were computed using the scintillator measurements as the benchmark.PACS number(s): 87.56.Fc

Objective methods to measure daily energy expenditure in studies of aging are needed. We sought to determine the accuracy of total energy expenditure (TEE) and activity energy expenditure (AEE) estimates from the SenseWear Pro armband (SWA) using software versions 6.1 (SWA 6.1) and 5.1 (SWA 5.1) relative to criterion methods in free-living older adults. Participants (n = 19, mean age 82.0 years) wore a SWA for a mean ± SD 12.5 ± 1.1 days, including while sleeping. During this same period, criterion values for TEE were assessed with doubly labeled water and for resting metabolic rate (RMR) with indirect calorimetry. AEE was calculated as 0.9 TEE - RMR. For TEE, there was no difference in mean ± SD values from doubly labeled water (2,040 ± 472 kcal/day) versus SWA 6.1 (2,012 ± 497 kcal/day, p = .593) or SWA 5.1 (2,066 ± 474 kcal/day, p = .606); individual values were highly correlated between methods (SWA 6.1 r = .893, p < .001; SWA 5.1 r = .901, p < .001) and demonstrated strong agreement (SWA 6.1 intraclass correlation coefficient = .896; SWA 5.1 intraclass correlation coefficient = .904). For AEE, mean values from SWA 6.1 (427 ± 304 kcal/day) were lower by 26.8% than criterion values (583 ± 242 kcal/day, p = .003), and mean values from SWA 5.1 (475 ± 299 kcal/day) were lower by 18.5% than criterion values (p = .021); however, individual values were highly correlated between methods (SWA 6.1 r = .760, p < .001; SWA 5.1 r = .786, p < .001) and demonstrated moderate agreement (SWA 6.1 intraclass correlation coefficient = .645; SWA 5.1 intraclass correlation coefficient = .720). Bland-Altman plots identified no systematic bias for TEE or AEE. Acceptable levels of agreement were observed between SWA and criterion measurements of TEE and AEE in older adults.

The input of pathologists is essential for the conduct of many forms of research, including clinical trials. As the custodians of patient samples, pathology departments have a duty to ensure compliance with the relevant regulations, standards and guidelines to ensure the ethical and effective use for their intended investigational analysis, including when patients are participating in a research study. The results of research studies have impacts beyond the research study itself as they may inform changes in policy and practice or support the licensing of medicines and devices. Compliance with regulations and standards provides public assurance that the rights, safety and wellbeing of research participants are protected, that the data have been collected and processed to ensure their integrity and that the research will achieve its purpose. The requirements of the regulatory environment should not be seen as a barrier to research and should not significantly impact on the work of the laboratory once established and integrated into practice. This paper highlights important regulations, policy, standards and available guidance documents that apply to research involving NHS pathology departments and academic laboratories that are contributing to research involving human subjects.