System Design Code Research Articles

The Effect of the New Working Days System on Employees Productivity in Sharjah

Unique Contribution to Theory, Practice and Policy: Lastly, future research might consider longer-term data collection methods and more intricate ways to gauge how employees react to work-life balance based on four working days in a week. The HRM needs to reconsider the current economic climate because the employees have access to a variety of offers in the market. Therefore, it is beneficial for the organization to start providing perks to their potential employees. There is a high risk of employee turnover if they are not satisfied with the job, in this case, the implication of the four working days policy can benefit the workplace. By using relevant keywords like Work system design, job satisfaction, employee performance, productivity, and JEL codes (J24, J28, and M54) the study becomes more noticeable and accessible. Our study implications emphasized the importance of performance metrics, including productivity and job satisfaction.

Research on Design Pattern Detection Method Based on UML Model with Extended Image Information and Deep Learning

Detecting relevant design patterns from system design or source code helps software developers and maintainers understand the ideas behind the design of large-scale, highly complicated software systems, thereby improving the quality of software systems. Currently, design pattern detection based on machine learning has become a hot research direction. Scholars have proposed many design pattern detection methods based on machine learning. However, most of the existing literature only reports the utilization of traditional machine learning algorithms such as KNN, decision trees, ANN, SVM, etc., which require manual feature extraction and feature selection. It is very difficult to find suitable and effective features for the detection of design patterns. In the previous research, we have initially explored a design pattern detection method based on graph theory and ANN. Based on the research work done, we speculate that if we can realize the end-to-end design pattern detection from system design or source code to design pattern with the help of the powerful automatic feature extraction and other advantages of deep learning, the detection effect can be further improved. This paper intends to first explore a UML model that extends image information, called colored UML, so as to transform the design pattern detection problem into an image classification problem; on this basis, the positive and negative sample sets and the system to be recognized are all expressed in the form of colored UML models, the convolutional neural network VGGNet is used to train the data set to extract features, and the extracted features are trained by the SVM for binary classification to judge the pattern instances. Experiments were carried out on three open-source projects. We used three non-machine learning design pattern detection methods and five design pattern detection methods based on traditional machine learning algorithms, as well as the method in this paper. In general, the method proposed in this paper achieved higher precision and recall, and for different programs and their patterns, the precision and recall were stable at more than 85% in most cases. The experimental results demonstrate that this paper can achieve a better effect in recognizing design patterns. The research is, therefore, of both theoretical significance and application value.

A field test of a federated learning/federated analytic blockchain network implementation in an HPC environment

The rapid upswing in interest in federated learning (FL) and federated analytics (FA) architectures has corresponded with the rapid increase in commercial AI software products, ranging from face detection and language translation to connected IOT devices, smartphones, and autonomous vehicles equipped with high-resolution sensors. However, the traditional client-server model does not readily address questions of data ownership, privacy, and data location in the context of the multiple datasets required for machine learning. In this paper, we report on a pilot distributed ledger and smart contract network model, designed to track analytic jobs in an HPC supercomputing environment. The test system design integrates the FL/FA model into a blockchain-based network architecture, wherein the test system records interactions with the global server and blockchain network. The design goal is to create a secure audit trail of supercomputer analytic operations and the ability to securely federate those operations across multiple supercomputer deployments. As there are still relatively few real-world applications of FL/FA models and blockchain networks in use, our system design, test deployment, and sample code are intended to provide interested researchers with exploratory tools for future research.

Critical Analysis of the New High Cycle Fatigue Assessment Procedure From ASME B31.3—Appendix W

Abstract ASME B31.3, the leading process piping system design code, has included in its 2018 edition a new procedure for evaluation of high cycle fatigue in process piping systems. As stated in the Appendix W of ASME B31.3-2018, this new procedure is applicable to any load resulting in the stress range in excess of 20.7 MPa (3.0 ksi) and with the total number of cycles exceeding 100,000. However, this new procedure is based on the stress range calculation typical to ASME B31 codes which underestimates the realistic expansion stress range by a factor of ∼2. While the allowable stress range used typically for fatigue evaluation of piping systems is adjusted to take into consideration this fact, the new fatigue design curves seem not to take it into account. Moreover, the applicability of the new design procedure (i.e., welded joint fatigue design curves) to the components which tend to fail away from the bends is questionable. Two examples are presented at the end of the paper in order to substantiate the indicated inconsistencies in the verification philosophy.

A Study of Feature Scattering in the Linux Kernel

Feature code is often scattered across a software system. Scattering is not necessarily bad if used with care, as witnessed by systems with highly scattered features that evolved successfully. Feature scattering, often realized with a pre-processor, circumvents limitations of programming languages and software architectures. Unfortunately, little is known about the principles governing scattering in large and long-living software systems. We present a longitudinal study of feature scattering in the Linux kernel, complemented by a survey with 74, and interviews with nine Linux kernel developers. We analyzed almost eight years of the kernel's history, focusing on its largest subsystem: device drivers. We learned that the ratio of scattered features remained nearly constant and that most features were introduced without scattering. Yet, scattering easily crosses subsystem boundaries, and highly scattered outliers exist. Scattering often addresses a performance-maintenance tradeoff (alleviating complicated APIs), hardware design limitations, and avoids code duplication. While developers do not consciously enforce scattering limits, they actually improve the system design and refactor code, thereby mitigating pre-processor idiosyncrasies or reducing its use.

A new wind turbine icing computational model based on Free Wake Lifting Line Model and Finite Area Method

Based on the Free Wake Lifting Line (FWL) Model and Finite Area Method (FAM), a new wind turbine icing computational model, named FFICE, is developed in this paper. By utilizing the fast calculation characteristics of the FWL model, the 3D flow field of wind turbine can be computed. According to the results, the 3D icing problem is transformed into different 2D conditions along the span of the blade. Then, the Lagrangian Method is applied to calculate the collection efficiency on the surface of the local airfoil. In order to accurately simulate the ice accretion, the heat and mass transfer process in the water film is solved by the modified FAM numerical computational method. All the modules involved in FFICE model is validated according to the numerical or experimental results. After that, the dynamic characters of the water film during the icing process on NACA 0012 airfoil is analyzed. At last the icing analysis of NREL Phase VI wind turbine is performed and the results are discussed in detail. The FFICE model provides an effective way for wind turbine icing analysis, which could be easily incorporated into the Icing Protection System (IPS) design code.

Design and Optimization of Joint Iterative Detection and Decoding Receiver for Uplink Polar Coded SCMA System

SCMA and polar coding are possible candidates for 5G systems. In this paper, we firstly propose the joint iterative detection and decoding (JIDD) receiver for the uplink polar coded sparse code multiple access (PC-SCMA) system. Then, the EXIT chart is used to investigate the performance of the JIDD receiver. Additionally, we optimize the system design and polar code construction based on the EXIT chart analysis. The proposed receiver integrates the factor graph of SCMA detector and polar soft-output decoder into a joint factor graph, which enables the exchange of messages between SCMA detector and polar decoder iteratively. Simulation results demonstrate that the JIDD receiver has better BER performance and lower complexity than the separate scheme. Specifically, when polar code length $N=256$ and code rate $R = 1/2$ , JIDD outperforms the separate scheme 4.8 and 6 dB over AWGN channel and Rayleigh fading channel, respectively. It also shows that, under 150% system loading, the JIDD receiver only has 0.3 dB performance loss compared to the single user uplink PC-SCMA over AWGN channel and 0.6 dB performance loss over Rayleigh fading channel.

Design Window Analysis for the Helical DEMO Reactor FFHR-d1

Conceptual design activity for the LHD-type helical DEMO reactor FFHR-d1 has been conducted at the National Institute for Fusion Science under the Fusion Engineering Research Project since FY2010. In the first step of the conceptual design process, design window analysis was conducted using the system design code HELIOSCOPE by the “Design Integration Task Group”. On the basis of a parametric scan with the core plasma design based on the DPE (Direct Profile Extrapolation) method, a design point having a major radius of 15.6 m and averaged magnetic field strength at the helical coil winding center of 4.7 T was selected as a candidate. The validity of the design was confirmed through the analysis by the related task groups (in-vessel component, blanket, and superconducting magnet).

Explicit use-case representation in object-oriented programming languages

Use-cases are considered an integral part of most contemporary development processes since they describe a software system's expected behavior from the perspective of its prospective users. However, the presence of and traceability to use-cases is increasingly lost in later more code-centric development activities. Use-cases, being well-encapsulated at the level of requirements descriptions, eventually lead to crosscutting concerns in system design and source code. Tracing which parts of the system contribute to which use-cases is therefore hard and so limits understandability. In this paper, we propose an approach to making use-cases first-class entities in both the programming language and the runtime environment. Having use-cases present in the code and the running system will allow developers, maintainers, and operators to easily associate their units of work with what matters to the users. We suggest the combination of use-cases, acceptance tests, and dynamic analysis to automatically associate source code with use-cases. We present UseCasePy, an implementation of our approach to use-case-centered development in Python, and its application to the Django Web framework.

Tritium Fuel System Assessment on Economics and CO2 Emissions in DT Fusion Reactors

The contribution of tritium fuel system construction and operation to the global COE and the life-cycle GHG emissions is analysed using PEC reactor system design code for both magnetic confinement fusion (MCF) and inertial confinement fusion (ICF) reactors. This contribution is less than a few percents in the present model, but the CO2 emissions from the ICF fuel system are rather higher than those from MCF, because of the DT pellet fabrication processes.

Importance of helical pitch parameter in LHD-type heliotron reactor designs

One of the key issues in the design of LHD-type heliotron reactors is to secure sufficient blanket spaces. In this respect, helical pitch parameter γ is quite important because it significantly affects both the coil and plasma shapes. For a quantitative understanding of the effect of helical pitch parameter on a design window, a system design code for LHD-type heliotron reactors HELIOSCOPE (HELIOtron System design COde for reactor Performance Evaluation) is developed and parametric scans are carried out with three cases of γ = 1.15, 1.20 and 1.25. It became clear that design windows of heliotron reactors depend significantly on the engineering constraints: the stored magnetic energy of the coil system, the inboard minimum blanket space and the averaged neutron wall load. In the case of a fusion power of 3 GW, γ = 1.20 is optimum for relaxing physics requirements. But γ = 1.15 is also a possible selection if a lower fusion power or a higher neutron wall load is accepted. Since design windows are quite sensitive to the engineering constraints and physics conditions, a further detailed study on design feasibility of advanced engineering components and the effect of γ on the physics conditions is expected to optimize the value of γ.

A Robust Design Window for the Heliotron DEMO Reactors

According to the achievements in the Large Helical Device (LHD) experiments, a design of a DEMO reactor with a LHD-type heliotron system is foreseeable. On the other hand, a DEMO is the next step reactor and high reliability and feasibility are demanded in its design. In this study, a robust design window, i.e., the design window that is not sensitive to a change in uncertain physics parameters, was surveyed through parametric scans using a system design code. It was found that a difference in main design parameters (major radius, magnetic field strength, fusion output) gives only a small change in a dependence of physics requirements on the physics conditions. Therefore, it is important to find the design window with a lower requirement on the confinement improvement to assure the design robustness. In this respect, a reduction in the minimum inboard blanket space, one of the key parameters in a LHD-type heliotron reactor design, can effectively expand the design window and contributes to the design robustness. An acceptance of higher neutron wall load and an achievement of further high confinement improvement are also expected to make both a DEMO and a commercial reactor to be more feasible and economically attractive.

Core Plasma Design of a Heliotron Reactor

AbstractThe design of a core plasma with the LHD‐type heliotron configuration has been advanced. Recent design study of a LHD‐type heliotron reactor has shown that the increase in the reactor size is a possible solution to secure a sufficient blanket space. The increase in the reactor size enables a flexible selection of plasma configurations. In this respect, a commercial plant design with the plasma configuration which has a similar shape to that of LHD high‐beta plasma discharge was carried out. A parametric scan with a system design code showed that there exists the design window with engineering constraints and the physics constraints which can be extrapolated from the present experimental achievements. Finite‐beta equilibrium calculations by VMEC code showed that the last closed flux surface which has almost the same shape as that in vacuum equilibrium can be obtained by applying an appropriate additional vertical field (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Design windows and cost analysis on a helical reactor

Based on the recent experimental results of the LHD and the magnet technology–cost basis developed for the ITER construction, the design windows of helical reactors are analysed. For searching design windows and investigating their economical potential, we have developed a mass–cost estimating model linked with the system design code (HeliCos). We found that the LHD-type helical reactor has the technically and economically attractive design windows, where the major radius is increased as large as for the sufficient blanket space, but the magnetic stored energy is decreased to a reasonable level because of lower magnetic field with the convenient physics basis of the H factor near 1.1 to the ISS04 scaling and beta value of 5%.

Neutron wall loading of Tokamak reactors

Neutron wall loading (Γn) is a key parameter for the selection of fusion power core component materials. It also impacts the economic, performance, design, safety and environmental aspect of the fusion power plant. This paper reports the determination of the range of Γn for economically competitive fusion power plants based on the analysis that couples the MHD stability physics results to a system design code. Cost of electricity (COE) was selected as the parameter to be minimized. For both normal conducting and superconducting coil options, at thermal efficiency of 46% and at the power output range of 1–2 GW(e) the average neutron wall loading is 4–7 MW/m2. For a given power output, higher thermal efficiency will allow lower Γn. At the above range of Γn, in order to have economical fusion power reactors, for the solid first wall design option, high thermal efficiency of 46% to 57.5% requires the use of alloys like V and W-alloy, respectively. The corresponding COE can be projected to be in the economically competitive range of 62–54.6 mill/kWh.

Way to ICF reactor

A brief review is given of the objectives and conditions required to realize inertial fusion energy (IFE) power plants. Using a general system design code, an analysis of design windows for obtaining economically attractive IFE power plants is carried out. There are many options for IFE concepts — target irradiation, target heating, drivers and reaction chamber. In these combinations, the concepts that use laser for direct drive are considered the most promising approach because of the potential for achieving high gain targets and the recent progress of diode pumped solid state lasers. We analyzed the IFE development programs using network analysis methods. The results of the analysis show that the independence and modular characteristic of the IFE key system, such as laser and reaction chamber, could make IFE projects rather small in size and easy to promote with a step by step program. Therefore, the way to the ICF reactor is very flexible in decreasing the risks and selecting the optimum choice from a wide variety of options.

System Modeling and Reactor Design Studies of the Advanced Thermionic Initiative Space Nuclear Reactor

In-core thermionic space reactor design concepts that operate at a nominal power output range of 20 to 50 kW (electric) are described. Details of the neutronic, thermionic, thermal hydraulics, and shielding performance are presented. Because of the strong absorption of thermal neutrons by natural tungsten and the large amount of natural tungsten within the reactor core, two designs are considered. An overall system design code has been developed at Oregon State University to model advanced in-core therm ionic energy conversion-based nuclear reactor systems for space applications. The code modules include neutronics and core criticality, a thermionic fuel element (TFE) performance module with integral thermal-hydraulic calculation capability, a radiation-shielding module, and a module for the waste heat rejection. The results show that the driverless single-cell Advanced Thermionic Initiative (ATI) configuration, which does not have driver fuel rods, proved to be more efficient than the driven core, which has driver rods. The results also show that the inclusion of the true axial and radial power distribution decrease the overall conversion efficiency. The flattening of the radial power distribution by three different methods would lead to a higher efficiency. The results show that only one TFE works at the optimum emitter temperature; all other TFEs are off the optimum performance and result in a 40% decrease of the efficiency of the overall system. The true axial profile is significantly different as there is a considerable amount of neutron leakage out of the top and bottom of the reactor. The analysis reveals that the axial power profile actually has a chopped cosine shape. For this axial profile, the reactor core overall efficiency for the driverless ATI reactor version is found to be 5.84% with a total electrical power of 21.92 kW (electric). By considering the true axial power profile instead of the uniform power profile, each TFE loses ∼80 W(electric).

A Simple Scaling Approach to Calculate Activation Radiological Hazards in a Silicon Carbide First Wall

A simplified scaling law approach for calculating activation-induced radioactive inventories is extended and applied. The goal is to provide a sufficiently accurate, very fast method to calculate activation radioactive inventories as an integral part of tokamak system design codes. The method is applied to a silicon carbide first wall, but now all relevant daughter nuclides are considered, and the results are used to calculate various indexes that can be used to characterize environmental and safety characteristics of fusion reactors. The indexes obtained from the scaling laws are in reasonable agreement with those derived from inventories calculated directly from more time-consuming Monte Carlo methods. 10 refs., 4 figs., 7 tabs.