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Nuclear thermal propulsion is an evolving technology that can be utilized for long-distance space travel. This technology yields the advantage of a high thrust and specific impulse, but requires an examination of the potential design adjustments necessary to enhance its feasibility. The development of nuclear thermal propulsion requires a comprehensive understanding of the system-level behavior during transient and steady-state operation. This paper extends our previous research by including the proper handling of turbomachinery with multi-channel thermal hydraulic simulations only for steady-state solutions. The system-level approach presented here enables the treatment of the turbopump components through non-dimensional analysis that eliminates the assumption of constant efficiencies. All the other components within the system (e.g., reflector and core) can be discretized to multiple channels and layers, in which the full thermal hydraulic solution is established. The approach chosen here enables the realistic modeling of the propellant flow within the expander cycle by capturing the pressure losses, mass flow rate splits, and enthalpy gain for various operational conditions. The verification of the package is completed through point comparisons of previous investigations into similar system designs. Furthermore, sensitivity studies are used to benchmark the capabilities of the package and investigate solution variations due to the perturbation of operational conditions and regimes. The sensitivity studies performed here are important to capture variation in flow characteristics (e.g., temperature, pressure, mass flow rates) for different design objectives such as the thrust and specific impulse. This work demonstrates that system-level simulations lacking multi-channel capability and proper turbomachinery treatment may yield higher uncertainties in understanding the engine's response and characteristics to changing various requirements. This is extremely important when screening the design space of such propulsion systems and when transient simulations are required. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study of the seismic behavior of steel gravity frames with concrete on metal deck floor systems using multibay test specimens subjected to cyclic lateral loads. Fully bolted double-angle connections were used for the primary gravity connections under investigation. Key design variables and construction details under investigation include metal deck orientation, positioning of metal deck seams, and increased deck reinforcing ratios around the columns. Test specimens were simultaneously subjected to gravity loads and quasi-static displacement-controlled cyclic lateral loads. Results show that composite gravity connections exhibit substantial flexural stiffness, strength, and ductility, with some differences in response depending on connection design variables and construction details. Results from the system-level experiments using multibay test specimens demonstrate significant differences compared to previous subassembly tests, which indicates that the moment-resisting capacity of connections may potentially be underestimated in subassembly level tests. [ABSTRACT FROM AUTHOR]

The organization model has shifted from treating the workforce as machines to improving human centricworking environments. The Learning Organization is conceptualized as an organism that evolves through continuous learning to adapt with a constantly changing environment. School is a typical organization and many scholars argued to reconceptualize school as a learning organization. The Integrated Model of School as a Learning Organization (Kools & Stoll, 2016)) has been widely studied and tested in European schools, particularly in Wales. However, there is a gap in the research needed to understand the prerequisites of SLO transformation and thus to better prepare for reform. To explore the prerequisites of SLO, a researcher applies a qualitative approach to purposely collect secondary data from the eight empirical studies in Wales, Greece, Latvia, Spain, Bulgaria, Türkiye, and Italy. To conduct data analysis, a data coding strategy is employed to create the prerequisites and assign them to the main themes- System Level and School Level. To achieve the SLO transformation, the researcher then recommends a systematic reform that involves the education stakeholders, both at system level and at school level - to put forward the practice of the SLO seven actionoriented dimensions. Further meta-analysis research is recommended to widen the scope of conceptualizing antecedents of SLO transformation.

The organization model has shifted from treating the workforce as machines to improving human centricworking environments. The Learning Organization is conceptualized as an organism that evolves through continuous learning to adapt with a constantly changing environment. School is a typical organization and many scholars argued to reconceptualize school as a learning organization. The Integrated Model of School as a Learning Organization (Kools & Stoll, 2016)) has been widely studied and tested in European schools, particularly in Wales. However, there is a gap in the research needed to understand the prerequisites of SLO transformation and thus to better prepare for reform. To explore the prerequisites of SLO, a researcher applies a qualitative approach to purposely collect secondary data from the eight empirical studies in Wales, Greece, Latvia, Spain, Bulgaria, Türkiye, and Italy. To conduct data analysis, a data coding strategy is employed to create the prerequisites and assign them to the main themes-System Level and School Level. To achieve the SLO transformation, the researcher then recommends a systematic reform that involves the education stakeholders, both at system level and at school level - to put forward the practice of the SLO seven actionoriented dimensions. Further meta-analysis research is recommended to widen the scope of conceptualizing antecedents of SLO transformation. [ABSTRACT FROM AUTHOR]

Nuclear thermal propulsion is an evolving technology that can be utilized for long-distance space travel. This technology yields the advantage of a high thrust and specific impulse, but requires an examination of the potential design adjustments necessary to enhance its feasibility. The development of nuclear thermal propulsion requires a comprehensive understanding of the system-level behavior during transient and steady-state operation. This paper extends our previous research by including the proper handling of turbomachinery with multi-channel thermal hydraulic simulations only for steady-state solutions. The system-level approach presented here enables the treatment of the turbopump components through non-dimensional analysis that eliminates the assumption of constant efficiencies. All the other components within the system (e.g., reflector and core) can be discretized to multiple channels and layers, in which the full thermal hydraulic solution is established. The approach chosen here enables the realistic modeling of the propellant flow within the expander cycle by capturing the pressure losses, mass flow rate splits, and enthalpy gain for various operational conditions. The verification of the package is completed through point comparisons of previous investigations into similar system designs. Furthermore, sensitivity studies are used to benchmark the capabilities of the package and investigate solution variations due to the perturbation of operational conditions and regimes. The sensitivity studies performed here are important to capture variation in flow characteristics (e.g., temperature, pressure, mass flow rates) for different design objectives such as the thrust and specific impulse. This work demonstrates that system-level simulations lacking multi-channel capability and proper turbomachinery treatment may yield higher uncertainties in understanding the engine’s response and characteristics to changing various requirements. This is extremely important when screening the design space of such propulsion systems and when transient simulations are required.

Abstract This paper presents a compact thermal model for smartphones, Phone‐nomenon 2.0, to predict the thermal behavior of smartphones. In the beginning, non‐linearities of internal and external heat transfer mechanisms of smartphones and a compact thermal model for these non‐linearities have been studied and proposed. Then, an iterative simulation procedure to handle these non‐linearities was developed, and the basic simulation framework which is one option in Phone‐nomenon 2.0 was established and we call it Phone‐nomenon.Iter. Finally, the linearisation approach was applied, and model order reduction techniques to enhance and speed up the basic framework were employed, and these two options Phone‐nomenon.Lin and Phone‐nomenon.LinMOR were named. Compared with a commercial tool, ANSYS Icepak, Phone‐nomenon.Iter can achieve two orders of magnitude speedup with the maximum error being less than 1.90% for steady‐state simulations and three orders of magnitude speedup with the temperature difference being less than 0.65°C for transient simulations. In addition, the speedup of Phone‐nomenon.Lin over Phone‐nomenon.Iter can be at least 4.22× and 3.26× for steady‐state and transient simulations, respectively. Moreover, the speedup of Phone‐nomenon.LinMOR over Phone‐nomenon.Lin is at least 2.57×.

Ultra reliable low latency communication (URLLC) is a use case of 5G which requires high reliability and low latency. We need to evaluate the capability of various physical layer technologies in achieving such high quality of services (QoS) in realistic channels, so as to devise novel technologies which can bridge the gaps identified. In this paper, we are using VIENNA 5G simulator to achieve 5G URLLC, by combining system and link level simulations, using the third generation partnership project (3GPP) specifications for 5G. Extensive simulation data is analyzed to evaluate the QoS and radio resource efficiency of various physical layer techniques to achieve 5G URLLC. We calculate the threshold signal to noise ratio (SNR) in additive white Gaussian channel (AWGN) which can be used for link adaptation in URLLC when using short packets. Closed loop link adaptation and macro-diversity are found to be more effective methods to achieve high reliability as compared to open loop micro-diversity. Relaxed error target per macro-diversity link is shown to provide better radio resource efficiency as compared to using same error target for all links. It is also shown that flexible subcarrier spacing and mini-slot level scheduling can support required transmission delay so as to meet the target end-to-end latency. [ABSTRACT FROM AUTHOR]

This paper presents a compact thermal model for smartphones, Phone‐nomenon 2.0, to predict the thermal behavior of smartphones. In the beginning, non‐linearities of internal and external heat transfer mechanisms of smartphones and a compact thermal model for these non‐linearities have been studied and proposed. Then, an iterative simulation procedure to handle these non‐linearities was developed, and the basic simulation framework which is one option in Phone‐nomenon 2.0 was established and we call it Phone‐nomenon.Iter. Finally, the linearisation approach was applied, and model order reduction techniques to enhance and speed up the basic framework were employed, and these two options Phone‐nomenon.Lin and Phone‐nomenon.LinMOR were named. Compared with a commercial tool, ANSYS Icepak, Phone‐nomenon.Iter can achieve two orders of magnitude speedup with the maximum error being less than 1.90% for steady‐state simulations and three orders of magnitude speedup with the temperature difference being less than 0.65°C for transient simulations. In addition, the speedup of Phone‐nomenon.Lin over Phone‐nomenon.Iter can be at least 4.22× and 3.26× for steady‐state and transient simulations, respectively. Moreover, the speedup of Phone‐nomenon.LinMOR over Phone‐nomenon.Lin is at least 2.57×. [ABSTRACT FROM AUTHOR]

Abstract Laser wireless power transmission technology avoids the traditional cable transmission requirements regarding the territory and environment, and facilitates vehicle-mounted laser wireless power transmission to provide accompanying power supplies to multi-target unmanned clusters. This can reduce the dependence of unmanned equipment (especially unmanned aerial vehicles) on power storage batteries, providing broad application prospects for the battlefield. However, the current laser wireless power transmission technology lacks a standardized technical index system and mature test and evaluation method; this is not conducive to the application of this technology in diverse combat scenarios. Accordingly, this paper proposes specific indicators for the component-level and system-level performance testing of laser wireless power transmission technology and constructs a corresponding test system and evaluation method, providing a yardstick for selecting laser wireless power transmission systems adapted to the battlefield.

In this paper, we propose a copula‐based approach to study the allocation problem of hot standbys in series systems composed of two heterogeneous and dependent components. By assuming that the lifetimes of components and spares are dependent and linked via a general survival copula, optimal allocation strategies are presented for the case of one and two redundancies at the component level. Further, redundancies allocation mechanisms are also compared between the allocations at the component level and the system level. For the case of one hot standby, we find that the performance of the redundant system at the component level is always worse than that at the system level. For the case of two hot standbys, the reversed allocation principle (i.e., Barlow–Proschan principle) is valid. Numerical examples and applications are also provided as illustrations. A real application on improving tensile strength of cables in high voltage electricity transmission network systems is presented for showing the applicability of our results. [ABSTRACT FROM AUTHOR]

A shake-table test of a 2-story full-scale low-damage concrete wall building was conducted on the multifunctional shake-table array at Tongji University to validate the system-level dynamic response of this type of building. The test building implemented state-of-art low-damage structural systems, including post-tensioned (PT) precast concrete walls, precast concrete frames with slotted beam connections, and a variety of energy-dissipating devices. The building was subjected to 39 separate earthquake tests, consisting of a range of structural design configurations and ground motions including different intensity records, far-field and near-fault records, and short- and long-duration records. The test data and documentation recorded throughout the project have provided a significant high-quality data set for improving understanding both global and local response of post-tensioning concrete wall buildings. The data set has been published and is publicly available. The methodology of the test documentation and data collection for each stage of the project are described, and a road map for navigating the archived data set is provided to support its future use. [ABSTRACT FROM AUTHOR]

Laser wireless power transmission technology avoids the traditional cable transmission requirements regarding the territory and environment, and facilitates vehicle-mounted laser wireless power transmission to provide accompanying power supplies to multi-target unmanned clusters. This can reduce the dependence of unmanned equipment (especially unmanned aerial vehicles) on power storage batteries, providing broad application prospects for the battlefield. However, the current laser wireless power transmission technology lacks a standardized technical index system and mature test and evaluation method; this is not conducive to the application of this technology in diverse combat scenarios. Accordingly, this paper proposes specific indicators for the component-level and system-level performance testing of laser wireless power transmission technology and constructs a corresponding test system and evaluation method, providing a yardstick for selecting laser wireless power transmission systems adapted to the battlefield. [ABSTRACT FROM AUTHOR]

Automated dispensing cabinet (ADC) overrides are used to access emergent or urgent medications when time delay from computerized provider order entry may result in patient harm. [1] Although necessary, ADC overrides bypass the safety features of order entry and verification which increase the risk of an error occurring and potential patient harm. To protect patient safety, national organizations such as The Joint Commission and Institute for Safe Medication Practices have called for hospitals to review overriding trends and available medications on override. AdventHealth Central Florida Division – South (CFD-S) met the recommendations to track overrides but there was limited understanding of the data. A quality improvement project was necessary to investigate the division's risk of error and identify interventions to proactively limit patient risk. The initial task of the quality improvement project was to create a standardized ADC override report that could be shared with pharmacy and nursing leaders within AdventHealth CFD-S monthly. As the project progressed, multiple interventions were identified such as standardizing the information reflected in the report, improving education about ADC overrides across multi-disciplinary departments, and critically reviewing the data to identify needed changes within the division. The efforts to share the ADC override metrics across all levels has improved understanding of ADC override goals and intentions of monitoring ADC overrides. This has paved the path to improving ADC override unit culture and identify gaps within the system that allows overrides to occur. [ABSTRACT FROM AUTHOR]

In the vast inland areas of China, more than 3 million bridges have been built to connect the remote mountainous areas and also to make up the urban transportation networks. For these bridges, reinforced concrete is the most widely adopted material in construction. Unlike the offshore bridges subjected to chloride-induced corrosion, the inland bridges have been constantly threatened by atmospheric carbonation-induced corrosion. The inland areas of China are earthquake-prone regions where several major seismic events occurred in recent years. To investigate the seismic vulnerability of inland bridges subjected to atmospheric carbonation-induced corrosion, the time-dependent characteristics of carbonation were analyzed based on an illustrative cable-stayed bridge, and the time-dependent damage states of bridge components during earthquakes were identified through the material strains of reinforcing steel and concrete. A life-cycle fragility assessment method was proposed and was used to establish the time-dependent seismic fragility curves of the illustrative cable-stayed bridge at the component and system levels. Based on the time-dependent fragility analysis, the macro identification for the seismic damage to bridge system under each damage state and its influence on traffic and repair levels were discussed, the damage sequences of bridge components for different damage states were predicted, and the application strategies of the prediction for components' damage sequences at various service periods were introduced. The research shows that the stirrups tend to be corroded first, leading to rapid decreases of the characteristic strain values of the confined core concrete; and the longitudinal reinforcement experiences very slight corrosion during the bridge's service life. The atmospheric carbonation-induced corrosion increases significantly the damage probabilities of the various bridge components, and consequently change their damage sequences at different damage states. However, the carbonation-induced corrosion does not change the CDPs (complete damage points) and MDPs (maximum damage points) of various bridge components. The bridge system is vulnerable during earthquakes and significantly affected by material degradation. Within the design service life, the damage probabilities of the bridge system can be increased by 0.5620 by the carbonation-induced corrosion, the PGAs (peak ground accelerations) corresponding to CDPs can be decreased by 0.1 g, and the MDPs of the failure state can gradually convert to the CDPs. It is possible to predict the damage sequences of the bridge components during earthquakes on the basis of seismic fragility analysis for different service periods of the bridge, based on which the corresponding maintenance and retrofit strategies can then be determined to protect the bridge against possible earthquakes, and the costs can be reduced. [ABSTRACT FROM AUTHOR]

The increasing need to reduce damage and downtime in modern buildings has led to the development of a low‐damage design philosophy, where the earthquake loads can be resisted with damage confined to easily replaceable components. Post‐tensioned (PT) concrete walls have emerged as a popular low‐damage structural system that have been implemented in a range of buildings. In order to provide essential evidence to support the development of low‐damage concrete structures, a system‐level shake‐table test was conducted on a two‐storey low‐damage concrete wall building implementing state‐of‐art design concepts. The test building included PT rocking walls that provide the primary lateral‐load resistance in both directions, a frame that utilized slotted beam connections, and a range of alternative energy dissipation devices that were installed at wall base or/and beam‐column joints. The building was subjected to 39 tests with a range of intensity ground motions, incorporating both unidirectional and bidirectional ground motions on the structure with different combinations of wall strength and energy dissipating devices. The building performed exceptionally well during the intense series of tests, confirming the suitability of both the design methods and the connection detailing implemented. The building achieved an immediate occupancy performance objective even when subjected to maximum considered earthquake hazard shaking. The building exhibited only minor damage at the conclusion of testing, with distributed cracking in the floors and cosmetic spalling in the wall toes that did not compromise structural capacity or integrity and could be easily repaired with minimal disruption. The test has provided a rich dataset that is available for further analysis of the building response and validation of design methods and numerical models. [ABSTRACT FROM AUTHOR]

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Area and power consumption of an integrated circuit chip is strongly related to its operating frequency. Using the switching principle of the gate-level circuit under different frequencies and keeping the original design, a system level chip area and power consumption optimization method based on dynamic frequency adjustment is proposed in this paper. Firstly, the relationships of area vs. frequency and power consumption vs. frequency are established by choosing the multiple test sets which satisfy the restricting constraints. Secondly, the mathematical models of area vs. frequency and power consumption vs. frequency are derived. Then, the optimal operating frequency is obtained by resolving the models. With a tape out design, the proposed method achieved about 0.59% area shrink and about 9.01% reduction in power consumption.

Modelling and simulation of a high voltage-level modular multilevel converter (MMC) is challenging due to large amount of semiconductor switches, various submodule (SM) circuits, and different operating conditions. Several equivalent models have been proposed for modelling and simulation in system level, which did not consider an industrial or digital controller. To accelerate MMC station design, a highly efficient model is needed with considering control parameters/strategies and accurate dynamics of voltage/current. In this study, an improved equivalent circuit model (ECM) is developed for large-scale system simulation and MMC station design. The proposed ECM considered the MMCs based on various SM circuits under different operating conditions. It can generate bipolar arm voltage and simulate static compensator under dc fault condition. Based on the proposed ECM, the influences of simulation time step on accuracy/efficiency are investigated by considering the sample period and voltage balancing strategies. This research is conducted based on an MMC-HVDC system in the PSCAD/EMTDC software. The study results demonstrate the effectiveness of the proposed ECM and show the relationship between simulation accuracy/efficiency and control/simulation parameters for determining simulation time step. Based on study results, the computational efficiency of proposed model is not significantly affected by the complexity of SM circuit. [ABSTRACT FROM AUTHOR]

DNA methylation plays a critical role in tumorigenesis through regulating oncogene activation and tumor suppressor gene silencing. Although extensively analyzed, the implication of DNA methylation in gene regulatory network is less characterized. To address this issue, in this study we performed an integrative analysis on the alteration of DNA methylation patterns and the dynamics of gene regulatory network topology across distinct stages of stomach cancer. We found the global DNA methylation patterns in different stages are generally conserved, whereas some significantly differentially methylated genes were exclusively observed in the early stage of stomach cancer. Integrative analysis of DNA methylation and network topology alteration yielded several genes which have been reported to be involved in the progression of stomach cancer, such as IGF2, ERBB2, GSTP1, MYH11, TMEM59, and SST. Finally, we demonstrated that inhibition of SST promotes cell proliferation, suggesting that DNA methylation-associated SST suppression possibly contributes to the gastric cancer progression. Taken together, our study suggests the DNA methylation-associated regulatory network analysis could be used for identifying cancer-related genes. This strategy can facilitate the understanding of gene regulatory network in cancer biology and provide a new insight into the study of DNA methylation at system level.

Highlights • A modeling approach is proposed to capture the behavior of a RCM shear wall building subjected to Quasi-Static cyclic lateral load. • Macro-models are developed for individual walls and refined to match experimental results. • Values for the factors controlling the behavior of wall models under cyclic lateral loads are proposed. • Non-linear torsional behavior of flanged walls has a considerable effect on the behavior of a building subjected to rotation under lateral load. • An approach for modeling of structures taking into account the global behavior of the building and the interaction between its components is presented. Abstract This paper presents numerical modeling of a two-story third-scale reinforced concrete masonry building composed of walls in orthogonal directions and subjected to quasi-static cyclic lateral loading up to failure. OpenSees and Response-2000 were used to capture the behavior at the section level as well as that at the element and system levels. The results of ten experimentally tested individual walls were used to verify the modeling approach that was used to generate the building model. The models were able to accurately capture the response of individual walls and that of the tested building. Force based elements were used to represent the walls and values for the factors controlling the cyclic behavior of masonry and steel material models used were recommended. The maximum error obtained for the strength of all wall models and for the building model was 4% and 12% respectively. Numerical results showed that overall ductility of the building was higher than that of its constituent walls especially under eccentric load which was consistent with experimental results. The torsional response of flanged walls was found to be essential for the accurate representation of the building behavior under eccentric lateral loading. [ABSTRACT FROM AUTHOR]

DNA methylation plays a critical role in tumorigenesis through regulating oncogene activation and tumor suppressor gene silencing. Although extensively analyzed, the implication of DNA methylation in gene regulatory network is less characterized. To address this issue, in this study we performed an integrative analysis on the alteration of DNA methylation patterns and the dynamics of gene regulatory network topology across distinct stages of stomach cancer. We found the global DNA methylation patterns in different stages are generally conserved, whereas some significantly differentially methylated genes were exclusively observed in the early stage of stomach cancer. Integrative analysis of DNA methylation and network topology alteration yielded several genes which have been reported to be involved in the progression of stomach cancer, such as IGF2 , ERBB2 , GSTP1 , MYH11 , TMEM59 , and SST. Finally, we demonstrated that inhibition of SST promotes cell proliferation, suggesting that DNA methylation-associated SST suppression possibly contributes to the gastric cancer progression. Taken together, our study suggests the DNA methylation-associated regulatory network analysis could be used for identifying cancer-related genes. This strategy can facilitate the understanding of gene regulatory network in cancer biology and provide a new insight into the study of DNA methylation at system level. [ABSTRACT FROM AUTHOR]

The uncertainties associated with technology‐specific and geography‐specific degradation rates make it difficult to calculate the levelized cost of energy, and thus the economic viability of solar energy. In this regard, millions of fielded photovoltaic modules may serve as a global testbed, where we can interpret the routinely collected time series maximum power point (MPP) data to assess the time‐dependent "health" of solar modules. The existing characterization methods, however, cannot effectively mine/decode these datasets to identify various degradation pathways. In this paper, we propose a new methodology called the Suns‐Vmp method, which offers a simple yet powerful approach to monitoring and diagnosing time‐dependent degradation of solar modules by using the MPP data. The algorithm reconstructs "IV" curves by using the natural illumination‐dependent and temperature‐dependent daily MPP characteristics as constraints to fit physics‐based circuit models. These synthetic IV characteristics are then used to determine the time‐dependent evolution of circuit parameters (eg, series resistance), which in turn allows one to deduce the dominant degradation modes (eg, solder bond failure) of solar modules. The proposed method has been applied to a test facility at the National Renewable Energy Laboratory. Our analysis indicates that the solar modules degraded at a rate of ~0.7%/year because of discoloration and weakened solder bonds. These conclusions are validated by independent outdoor IV measurements and on‐site imaging characterization. Integrated with physics‐based degradation models or machine learning algorithms, the method can also serve to predict the lifetime of photovoltaic systems. Inspired by the well‐known Suns‐Voc method, we have developed a novel technique called the Suns‐Vmp method that can interpret the routinely collected maximum power point (MPP) data of PV systems to produce insightful information regarding the underlying degradation mechanisms. The method can be applied to analyze solar modules installed across the globe to establish a comprehensive database of PV degradation. The resulting database will eventually facilitate geographic‐ and technology‐specific reliability‐aware design to improve module lifetime. [ABSTRACT FROM AUTHOR]

The aim of this study is to describe the authors' efforts to accomplish the green vehicular ad hoc network (GVANET) project. The goal is to realise the concept of a self 'renewably' powered communication infrastructure appropriate for intelligent transportation systems. The work in this project was started in 2009 with the intention of representing the necessary steps must be taken to achieve such system and to declare the usefulness of adopting environmental energy resources in building mission critical systems. The other objectives of this project are presenting a reasonably cost, reliable, secured and easy to install communication infrastructure. Their plan to implement the GVANET was achieved after passing two design levels: device level and system level. In the device level, they suggest that the architecture of a road side unit (RSU) must be enhanced to maintain its robustness and availability against the different failure events which may occur due to many reasons such as power supply shortage or denial of service attacks. The design philosophy in the system level concentrates on building a sustainable, secured, reliable and scalable communication infrastructure to solve the different systematic problems raised when implementing the RSU as a member of the GVANET. [ABSTRACT FROM AUTHOR]

User councils act as advisory bodies for the agencies with which they are associated. This article is based on interviews with user participants and agency representatives from a sample of user councils in Norway. The main question raised is how user participation functions in user councils. In general, the findings show that among the user councils there are active discussions, most of the user informants feel that they are respected as equal partners and that they are taken seriously. However, the work is characterized by representatives from the agencies taking the initiative to raise issues and the user representatives responding to these initiatives, and in that way the user participants function reactively. Most of the informants from the agencies want the user representatives to be more active and critical. This raises concerns about how user participants can be more proactive. Finally, some prerequisites for improving the functioning of user councils are discussed.

Low‐power consumption has become an important aspect of processors and systems design. Many techniques ranging from architectural to system level are available. Voltage scaling or frequency boosting methods are the most effective to achieve low‐power consumption as the dynamic power is proportional to the frequency and to the square of the supply voltage. The basic principle of operation of aggressive voltage scaling is to adjust the supply voltage to the lowest level possible to achieve minimum power consumption while maintaining reliable operations. Similarly, aggressive frequency boosting is to alter the operating frequency to achieve optimum performance improvement. In this study, an aggressive technique which employs voltage or frequency varying hardware circuit with the time‐borrowing feature is presented. The proposed technique double samples the data to detect any timing violations as the frequency/voltage is scaled. The detected violations are masked by phase delaying the flip‐flop clock to capture the late arrival data. This makes the system timing error tolerant without incurring error correction timing penalty. The proposed technique is implemented in a field programmable gate array using a two‐stage arithmetic pipeline. Results on various benchmarks clearly demonstrate the achieved power savings and performance improvement. [ABSTRACT FROM AUTHOR]

Tritium behavior in a DEMO reactor is a key design issue because of its self-sufficiency and impact on safety. Considering the difficulty in handling tritium, and that the transport, diffusion and permeation phenomena involve a large number of physical properties and parameters, it is intended to prepare a simulation tool to predict its behavior. A preliminary model for tritium transport at system level has been developed for the HCPB (Helium Cooled Pebble Bed) breeder concept (DEMO2014), focusing on the multi-physics of the release, diffusion, permeation, recombination processes. The numerical technique presented here is based on EcosimPro simulation tool, a program with an object-oriented nature which offers the possibility of mixing various disciplines by robust equation-solving algorithms. The study presents the results obtained in a reference case in which the most generic parameters provided by the HCPB designers have been used. Together with the breeder blanket concept, a tritium extraction system (TES) and a coolant purification system (CPS) have been included into the gases circuits. The results of tritium permeation to the coolant provide relatively low values (around 0.2 g/d), that will be improved in the future by a more detailed system description. [ABSTRACT FROM AUTHOR]

This work deals with power optimization of the audio processing back end for hearing aids-the interpolation filter, the sigma-delta ( $$\Sigma \Delta )$$ modulator and the Class D power amplifier (PA) as a whole. Specifications are derived, and insight into the trade-offs involved is used to optimize the interpolation filter and the $$\Sigma \Delta $$ modulator on the system level so that the switching frequency of the Class D PA-the main power consumer in the back end-is minimized. A figure-of-merit which allows judging the power consumption of the digital part of the back end early in the design process is used to track the hardware and power demands as the trade-offs of the system-level parameters are investigated. The result is the digital part of the back end optimized with respect to power which provides audio performance comparable to state-of-the-art. A combination of system-level parameters leading to the lowest switching frequency of the Class D power amplifier reported in the literature for the $$\Sigma \Delta $$ modulator-based back end is derived using this approach. [ABSTRACT FROM AUTHOR]

Energy minimization has been one of the major research challenges for access networks striving for green communication. Macrocell base stations (MBSs) are the main contributors to energy consumption, and the situation has become worse as more MBSs are being deployed to cope with the ever-increasing data traffic. Therefore, it will be crucial in the near future to minimize the energy consumption of MBSs. Based on various academic and industrial surveys, cellular systems involving both MBSs and small cell base stations (SBSs) are predicted to be the key network architecture for reducing the total energy consumption of access networks. In this paper, an efficient energy-saving transmission algorithm is proposed to minimize power consumption for transceivers in both MBSs and SBSs in cellular systems with a green deployment policy. The proposed algorithm enables grouped SBSs to be smartly activated/deactivated, according to dynamically fluctuating traffic loads, while maintaining the predetermined data rate requirements of all served users. Simulations of various traffic scenarios show that the presented approach performs better in terms of energy saving than the conventional approaches, providing an average improvement of around 20% under the employed real-world traffic pattern. [ABSTRACT FROM PUBLISHER]

Energy forecasting covers a wide range of prediction problems in the utility industry, such as forecasting demand, generation, price, and power load over time horizons and different power levels. Short-term load forecasting allows the system operator to make important decisions during network management and planning, which represents an economic improvement in the global electrical system, as well as acts as a fundamental component to address challenges imposed by the energy transition. Despite the urgent need, research into the current state-of-the-art in low voltage forecasting, other than at the smart meters level, has not yet been carried out in an in-depth way. We propose a systematic approach from system level to low voltage considering not only the performance of the models but also the applicability, interpretability, and reproducibility of the method/model. An initial benchmark model was compared against improved regression models enhanced by introducing new synthetic explanatory variables and a different regression technique, generalized additive models. The error was reduced by 42%–47% compared to the benchmark model, preserving the interpretability. Additionally, a simple ensemble method was evaluated to determine how it improves accuracy for specific periods, such as weekends, summer vacation, or public holidays, in which modeling is particularly difficult using standalone generalized additive models. The method was applied to the national power load and, for the first time, to all 100,000 secondary substations that integrate the Portugal power grid, rather than to tackle the few open datasets in this area. The approach was used to build a daily forecasting system live called PREDIS (Portuguese acronym for Distributed Prediction) whose outcomes are used to anticipate load peaks and network constraints in the context of the Portugal distribution system operator. • Systematic approach for short-term load forecasting at system and secondary substation levels. • Historical power, calendar, and weather variables modeled into a new interpretable forecasting model. • Detailed step-by-step variable modeling and an ensemble model evaluated for load forecasting at the system level. • A new private dataset of load timeseries from the 100,000 secondary substations of the Portugal power grid is analyzed. • Forecasting approach implemented as an innovative live system and adopted by the Portuguese DSO. [ABSTRACT FROM AUTHOR]

User councils act as advisory bodies for the agencies with which they are associated. This article is based on interviews with user participants and agency representatives from a sample of user councils in Norway. The main question raised is how user participation functions in user councils. In general, the findings show that among the user councils there are active discussions, most of the user informants feel that they are respected as equal partners and that they are taken seriously. However, the work is characterized by representatives from the agencies taking the initiative to raise issues and the user representatives responding to these initiatives, and in that way the user participants function reactively. Most of the informants from the agencies want the user representatives to be more active and critical. This raises concerns about how user participants can be more proactive. Finally, some prerequisites for improving the functioning of user councils are discussed. [ABSTRACT FROM PUBLISHER]

This paper presents a methodology to estimate the dissipation of energy in hardware, at any level of abstraction, with Powersim. Powersim is a C++ class library aimed to the calculation of energy dissipation of hardware described in SystemC. To this end C++ operators are monitored and a different energy model is used for each data type. Energy models are functions of operator inputs, constant parameters and variables, like supply voltage. The main advantage of this approach is that energy estimation does not require any change in the source code describing the hardware. As application examples, the computational complexity of a JPEG encoder, implemented in a FPGA, and a FIR filter, implemented in a microcontroller, are presented. [ABSTRACT FROM AUTHOR]

In this paper, a novel methodology for high-level modeling of bus communication in embedded systems is introduced. It allows the dynamic evaluation of their signal integrity (SI) characteristics at the virtual prototyping step (i.e., before physical realization). The method is based on the association of functional and nonfunctional modules. Functional modules represent the ideal behavior of the system, while nonfunctional modules use neural networks to model SI effects. This approach was implemented in SystemC-AMS, using the timed data flow model of computation. The method is illustrated by a Universal Serial Bus (USB) 3.0 application, where modular and parameterizable models are introduced. The method achieved good accuracy (<5%) while allowing significant simulation speedup (up to 2000 times), compared with SPICE-based reference models. This methodology can be used to perform an early SI analysis in the virtual prototyping of bus communication in the embedded systems. [ABSTRACT FROM PUBLISHER]

Despite the widespread use of traditional Chinese medicine (TCM) in clinical settings, proving its effectiveness via scientific trials is still a challenge. TCM views the human body as a complex dynamical system, and focuses on the balance of the human body, both internally and with its external environment. Such fundamental concepts require investigations using system-level quantification approaches, which are beyond conventional reductionism. Only methods that quantify dynamical complexity can bring new insights into the evaluation of TCM. In a previous article, we briefly introduced the potential value of Multiscale Entropy (MSE) analysis in TCM. This article aims to explain the existing challenges in TCM quantification, to introduce the consistency of dynamical complexity theories and TCM theories, and to inspire future system-level research on health and disease. [ABSTRACT FROM AUTHOR]

A new ESD failure mode under inductive IEC stress of automotive Controller Area Network (CAN) bus is identified. Inductor saturation causes increase of the rise-time from 1 ns to ~ 20 ns, leading to non-uniform conduction in the bidirectional ESD protection circuit. A novel mutual ballasting layout technique is introduced to recover the system level ESD performance. [ABSTRACT FROM AUTHOR]

A base station (BS) that enables multiple component carriers (CCs) to be jointly utilized for data transmissions is one of the most advanced cellular systems. This kind of BS aims to cope with the amazingly fast-growing demand from various users. However, such a BS is the most energy-intensive part of a cellular network because the activation of its additional CCs consumes a large amount of energy, which, in turn, causes environmental problems and higher costs for cellular operators. Consequently, how to efficiently save energy when using a multi-CC BS is an increasingly critical concern in the deployment of green cellular networks. This paper builds a practical framework for studying energy-efficient transmissions for a multi-CC BS from a system-level perspective involving both radio resource allocation and CC activation/deactivation, while also presenting several new transmission schemes for use in the multi-CC BS. In these schemes, a novel energy-saving algorithm for activating/deactivating CCs is combined with different radio resource allocation approaches, respectively. Simulation results demonstrate that these schemes have much better energy-saving performance than that of the conventional one. Furthermore, comparisons among the presented schemes are detailed. [ABSTRACT FROM PUBLISHER]

This paper introduces an LTE system level simulator and presents investigations of scenarios with differently balanced traffic emergence between uplink and downlink as well as inhomogeneous distribution of link direction asymmetry. In the TDD mode of LTE, duplexing is implemented via sharing the time domain between uplink and downlink users. This is done by different switching configurations, which offer varying capacity distributions between downlink and uplink, from a downlink-heavy configuration with 90 percent of the capacity in downlink direction to uplink heavy configurations with 60 percent uplink. We utilize the available capacity perfectly by adjusting the link configuration appropriately to traffic emergence. Performance gains when selecting a configuration appropriate to the arising traffic compared to usage of a static configuration with equally distributed capacity are investigated. In case of different configurations, additional interference can occur in neighbored cells due to distinct communication direction at the same time. We clarify the differences between these scenarios and quantify the gains and losses when the switching point between uplink and downlink is variable. [ABSTRACT FROM AUTHOR]

LTE networks are the latest generation of wireless networks based on IP architecture; it is standardized by the 3GPP in its Rel.8. LTE networks are implemented practically to access internet with very high data rates with using various multimedia services.This paper is based on five types of downlink packet scheduling algorithms in LTE networks,It examines the impact of throughput, the fairness and the spectral efficiency of each scheduling algorithms when the speed of UE (User Equipment) and the number of UEs are changed. A comparison between the scheduling algorithms has been done using Vienna LTE SYSTEM LEVEL Simulator. [ABSTRACT FROM AUTHOR]

In this paper, the principle of modularity is used to derive the different multilevel voltage and current source converter topologies. The paper is primarily focused on high-power applications and specifically on high-voltage dc systems. The derived converter cells are treated as building blocks and are contributing to the modularity of the system. By combining the different building blocks, i.e., the converter cells, a variety of voltage and current source modular multilevel converter topologies are derived and thoroughly discussed. Furthermore, by applying the modularity principle at the system level, various types of high-power converters are introduced. The modularity of the multilevel converters is studied in depth, and the challenges as well as the opportunities for high-power applications are illustrated. [ABSTRACT FROM AUTHOR]

Traditional Chinese medicine (TCM) has been gradually accepted by the world. Despite its widespread use in clinical settings, a major challenge in TCM is to study it scientifically. This difficulty arises from the fact that TCM views human body as a complex dynamical system, and focuses on the balance of the human body, both internally and with its external environment. As a result, conventional tools that are based on reductionist approach are not adequate. Methods that can quantify the dynamics of complex integrative systems may bring new insights and utilities about the clinical practice and evaluation of efficacy of TCM. The dynamical complexity theory recently proposed and its computational algorithm, Multiscale Entropy (MSE) analysis, are consistent with TCM concepts. This new system level analysis has been successfully applied to many health and disease related topics in medicine. We believe that there could be many promising applications of this dynamical complexity concept in TCM. In this article, we propose some promising applications and research areas that TCM practitioners and researchers can pursue. [ABSTRACT FROM AUTHOR]

In this study, the aspects of voltage stability related to voltage control and reactive power support in an active distribution grid are analysed, considering both static and dynamic system constrains. The analysis is carried out based on different international and local utility standards for voltage source converters (VSCs) and distribution. The ability of VSCs to provide reactive power support is explored in a structural way to improve voltage stability as well as power quality. The functional requirements of the VSCs are identified for this purpose in a generalised platform with the assumption of extension of the network automation till the distributed resources level. The step‐by‐step formulation of voltage stability and reactive power support requirements from system level are translated to VSC level for both static and dynamic system operation, aiming for a better system performance and new energy market scenario. The opportunity of tariff benefit would attract the DG operators as well as the customer for participating in system security through reactive power support and voltage profiling. The main contribution of the study lies in providing a comprehensive guideline for voltage control and reactive support of VSC interfaced DGs in active distribution combining the static and dynamic limitations. [ABSTRACT FROM AUTHOR]

A system level modeling methodology is presented and validated on a simple case. It allows precise simulations of electrostatic discharge (ESD) stress propagation on a printed circuit board (PCB). The proposed model includes the integrated circuit (IC) ESD protection network, IC package, PCB lines, passives components, and externals elements. The impact of an external component on the ESD propagation paths into an IC is demonstrated. Resulting current and voltage waveforms are analyzed to highlight the interactions between all the elements of an operating PCB. A precise measurement technique was designed and used to compare with the simulation results. The model proposed in this paper is able to predict, with good accuracy, the propagation of currents and voltages into the whole system during ESD stress. It might be used to understand why failures occur and how to fix them with the most suitable solution. [ABSTRACT FROM AUTHOR]

Relations occur on all levels of systems. Following a major assumption of generalized quantum theory, namely that the principles of quantum mechanics will occur on higher system levels as well, it was investigated in an a posteriori analysis of pre-existing data whether relational patterns found for two-photon experiments are similarly performed by two cell-populations. In particular, the typical pattern in outcomes of two-photon entanglement experiments was extrapolated to discover similar patterns of relationships in the cellular biological system of the Ciliate Paramecium caudatum. In the former case we find one photon assuming a particular state when being measured and the other assuming a correlated state with regard to the first particle. From a perspective of degrees of freedom ( df) the author interprets this outcome as follows: Each particle has only one df for assuming a particular state (e.g. its spin). When measured this is leading to a pattern: They use their two degrees of freedom for establishing a relation among them (particle-to-particle) and for a relation with the environment (particle-to-measurement). If this pattern is unique then we should find it also in cell-to-cell relationships. It was suggested to consider causations in cell-to-cell relations as the analogue to the relationship between the quantum particles (see above) and the dependence of repeating the experiments as the analogue to the measurement event in the quantum experiment. It was hypothesized that in a relational system of two cell populations only one should be sensitive to the repetition of the experiment. The other population, however, should establish a relation with the first one. Since the author had successfully performed experiments with pairs of cell populations that were separated with glass barriers from each other but having effects on each other (Fels in PLoS One 4:e5086, ), the system was perfectly well suited for testing the hypothesis. The assessed cell variable was cell division. An a posteriori analysis of three similar experiments confirmed that when populations were in a relation with each other, only one of them stood in relation with the repetition of the experiment. [ABSTRACT FROM AUTHOR]

To fulfill the requirement of final-user uncontrolled ESD environment, system-level ESD protection devices must survive repeated ESD stresses. This paper deals with the assessment of ESD protection device reliability toward repetitive stresses using statistical distribution. The proposed method could lead to better ESD robustness improvement than the simplistic “higher ESD robustness” requirement. [ABSTRACT FROM PUBLISHER]

In electronic systems, the ever-increasing level of integration is paced by component scaling. Consequently, system-level protection improvements in electrostatic discharge (ESD) reliability during a device's lifetime are mandatory. To this end, we have investigated bidirectional system-level ESD protection diodes that have been subjected to repetitive human metal model stresses. Our goal was to develop robust ESD components by understanding the physical and electrical behaviors of components after multiple ESD surges. In this paper, three ESD-induced failure modes of protection devices are demonstrated and analyzed in terms of severity, i.e., charge trapping in the silicon–oxide interface, metallic diffusion toward the contacts, and melted filaments in the silicon bulk at the junction periphery. [ABSTRACT FROM PUBLISHER]

System level analysis and design of a single-loop fourth-order sigma-delta (ΣΔ) accelerometer is presented to reduce quantization noise and enhance resolution of the micromachined accelerometer. Stability of the system is analyzed by root locus method based on the linear model established in this work. Theoretical analysis indicates that the forth-order ΣΔ micromachined accelerometer has good performance in noise, dead zone and idle tone. Based on the analysis and discussion of the system level, the transistor level design of the interface circuit is implemented, the circuit is fabricated in 0. 5 µm two poly two metal CMOS process, and the tested results indicate that the sensitivity is 1.2 V/g, nonlinearity is 0.2% , open-loop noise density is 12 µg/Hz1/2, closed-loop noise density is 80 u/Hz1/2 and the power dissipation is 40 mW. [ABSTRACT FROM AUTHOR]

We introduce an empirical method for power consumption modeling of analog components at system level. The principal step of this method uses neural networks to approximate the mathematical curve of the power consumption as a function of the inputs and parameters of the analog component. For a node of a wireless sensors network, we found an average error of 1.53% with a maximum error of 3.06% between our estimation and the measured power consumption. This novel method is suitable for Platform-Based Design and has three key features for architecture exploration purposes. Firstly, the method is generic as it can be applied to any analog component in any modeling and simulation environment. Secondly, the method is suitable for the total (analog and digital) power consumption estimation of a heterogeneous system. Thirdly, the method provides an online estimation of the instantaneous power consumption of analog blocks. [ABSTRACT FROM AUTHOR]

Abstract: This paper provides results of an application of a holistic systematic approach of water accounting using remote sensing and GIS coupled with groundwater modeling to evaluate water saving options by tracking non-beneficial evaporation in the Liuyuankou Irrigation System (LIS) of China. Groundwater rise is a major issue in the LIS, where groundwater levels have risen alarmingly close to the ground surface (within 1m) near the Yellow River. The lumped water balance analysis showed high fallow evaporation losses and which need to be reduced for improving water productivity. The seasonal actual evapotranspiration (ETs) was estimated by applying the SEBAL algorithm for 18 NOAA AVHRR-12 images over the year of 1990–1991 (April 1990–March 1991). This analysis was aided by the unsupervised land use classification applied to three Landsat 5 TM images of the study area. SEBAL results confirmed that a fair amount (116.7MCM) of water can be saved by reducing evaporation from fallow land which will result in improved water productivity at the irrigation system. The water accounting indicator (for the analysis period) shows that the process fraction per unit of depleted water (PFdepleted) is 0.52 for LIS, meaning that 52% of the depleted water is consumed by agricultural crops and 48% is lost through non-process depletion. Finally, the groundwater modeling was applied to simulate three land use and water management interventions to assess their effectiveness for both water savings and impact on the groundwater in LIS. MODFLOW''s Zone Budget code calculates the groundwater budget of user-specified subregions, the exchange of flows between subregions and also calculates a volumetric water budget for the entire model at the end of each time step. The simulation results showed that fallow evaporation could be reduced between 14.2% (25.51MCM) and 45.3% (81.36MCM) by interventions such as canal lining and groundwater pumping. The reduction in non-beneficial ETs volumes would mean that more water would be available for other uses and it would allow the introduction of more surface water supplies in the area through improved water management strategies. This will ultimately lead to improved water productivity of the LIS system. [Copyright &y& Elsevier]

Network centric approach to complex systems has been attracting a lot of attention in the recent past. With specific applications in space, military and other information enterprises, such an approach is capable of yielding autonomy at the system level. This article describes a distributed approach to information processing in sensor networks. The network architecture entails a hierarchy of capabilities, information and control, where nodes in the network are thoroughly or partially autonomous. The network also consists of slave nodes dedicated to sensing and gathering information. Individual nodes are expected to possess resources for networking and computing and presume autonomy through multi functional modules for sensory processing and situation assessment. Data association, registration and fusion are formulated into a joint process, and an expectation maximization (EM) approach is developed to solve the three problems simultaneously. A fuzzy cognitive map (FCM) is proposed to perform situation assessment, while a genetic algorithm (GA) is applied for learning, to identify an optimal structure. The distributed architecture is applied to coastal surveillance with simulations on the west coast of Canada. [ABSTRACT FROM PUBLISHER]