Kageyama (
1972
) presented a survey of resolvable solutions of balanced incomplete block designs. Clatworthy (
1973
) produced tables of two associate classes partially balanced designs in the ...practical range of r, k ≤ 10 and presented resolvable solutions whenever possible. Here, the minimum α (≤1) - resolvable solutions of partially balanced designs not found in Clatworthy (
1973
) and Saurabh and Sinha (
2020
) are presented. This paper is in sequel to the paper by Saurabh and Sinha (
2020
).
Summary
Microheat pipe cooled reactor power source (HRP) designed for space or underwater vehicles meets the future demands, such as safer structure, longer operating time, and fewer mechanical ...moving parts. In this paper, potassium heat pipe cooled reactor power source system which generates 50 kWe electricity is proposed. The reactor core using uranium nitride fuel is cooled by 37 potassium high‐temperature heat pipes. The shields are designed as tungsten and water, and reactor reactivity is controlled by control drums. The thermoelectric generator (TEG) consists of thermoelectric conversion units and seawater cooler. The thermoelectric conversion units convert thermal energy to electric energy through the high‐performance thermoelectric material. A code applied for designing and analyzing the reactor power system is developed. It consists of multichannel reactor core model, heat pipe model using thermal resistance network, thermoelectric conversion, and thermal conductivity model. Then, the sensitivity analysis is performed on two key parameters including the length of the heat pipe condensation section and the cold junction temperature of the TE cell. Meanwhile, the steady‐state calculations are conducted. Results show that the maximum fuel temperature is 938 K located in the center of reactor core and the outlet temperature of coolant reaches 316 K. Both of them are within the limitation. It is concluded that the preliminary design of HPR design is reasonable and reliable. The designed residual heat removal system has sufficient safety margin to release the decay heat of the reactor. This research provides valuable analysis for the application of micronuclear power source.
• A micronuclear reactor power source system typical of 50 kWe electricity is conceptual designed.
• Micronuclear reactor power source aims to apply in space station, underwater‐unmanned vehicles, and island power station.
• The sensitivity of nuclear power source's key parameters and steady‐state condition operating parameters are analyzed and simulated.
The paper presents a simplified static force-based procedure for seismic retrofit design of RC frames using internal eccentric steel braces (ESBs), connected to long beam at distance of L/8 from beam ...ends, to enhance seismic resistance of the frame. The technique uses the linear static procedure given in ASCE 7-16 for calculation of appropriate design base shear for frame analysis, and the AISC 360-16 seismic provisions for preliminary design of steel braces. Response modification factor
R
was derived based on simplified kinematics of rigid frame response and flexure hinging of link beam, to reduce the elastic base shear force for lateral load analysis of frame and design of steel braces. This shifts plastic hinges from columns, and reduces joint shear deformation, by means of capacity protected braces and beam shear. The procedure was used for the preliminary design of ESB retrofitting technique for a two-story RC frame, employing hollow box steel sections. Quasi-static cyclic tests were performed on both as-built and ESB retrofitted portal frame panels under multiple-levels of lateral displacements demands. The tests performed on frames were analysed to understand the damage mechanism and retrieve the essential seismic response properties: force–displacement capacity curves, hysteretic cyclic response and hysteretic damping, and to establish performance-based story drift limits. The experimental data was used to calibrate finite element based nonlinear numerical models in SeismoStruct. Nonlinear static pushover analysis of considered two-story ESB retrofitted frame was carried to quantify structure ductility and response modification factors. The preliminary design was verified through nonlinear time history analysis (NLTHA) for both design base earthquakes and maximum considered earthquakes. Proposed seismic design of ESB retrofit for multi-stories RC frames having three to six stories has been presented and verified through NLTHA. It indicates the promising behaviour of ESB retrofit technique as well as the efficiency of the proposed simplified design procedure.
This book is a practical guide to sensory evaluation methods and techniques in the food, cosmetic and household product industries. It explains the suitability of different testing methods for ...different situations and offers step-by-step instructions on how to perform the various types of tests. Covering a broad range of food and non-food product applications, the book is designed to be used as a practical reference in the testing environment; a training manual for new recruits into sensory science, and a course book for students undertaking industrial training or academic study.
Engineering design has proven to be a rich context for applying artificial intelligence (AI) methods, but a categorization of such methods applied in AI-based design research works seems to be ...lacking. This paper presents a focused literature review of AI-based methods mapped to the different stages of the engineering design process and describes how these methods assist the design process. We surveyed 108 AI-based engineering design papers from peer-reviewed journals and conference proceedings and mapped their contribution to five stages of the engineering design process. We categorized seven AI-based methods in our dataset. Our literature study indicated that most AI-based design research works are targeted at the conceptual and preliminary design stages. Given the open-ended, ambiguous nature of these early stages, these results are unexpected. We conjecture that this is likely a result of several factors, including the iterative nature of design tasks in these stages, the availability of open design data repositories, and the inclination to use AI for processing computationally intensive tasks, like those in these stages. Our study also indicated that these methods support designers by synthesizing and/or analyzing design data, concepts, and models in the design stages. This literature review aims to provide readers with an informative mapping of different AI tools to engineering design stages and to potentially motivate engineers, design researchers, and students to understand the current state-of-the-art and identify opportunities for applying AI applications in engineering design.
The problem of finding optimal block designs can be formulated as a combinatorial optimization, but its resolution is still a formidable challenge. This paper presents a general and user-friendly ...algorithm, namely Modified Particle Swarm Optimization (MPSO), to construct optimal or near-optimal block designs. It can be used for several classes of block designs such as binary, non-binary and test-control block designs with correlated or uncorrelated observations. In order to evaluate the algorithm, we compare our results with the optimal designs presented in some published papers. An advantage of our algorithm is its independency to the sizes of blocks and the structure of correlations.
The first practical guide to research methods in memory studies. This book provides expert appraisals of a range of techniques and approaches in memory studies, and focuses on methods and methodology ...as a way to help bring unity and coherence to this new field of study.
An optimal design method based on closed-form analytical solutions is proposed for a liquid storage tank with inerter isolation system. The storage tank is modeled accounting for the flexibility of ...the tank wall, and isolated by the inerter isolation system composed of an inerter, a damping element, and a spring element connected between the same two terminals in parallel. The stochastic response of the storage tank with inerter isolation system, in terms of sloshing height and isolation displacement, is derived in closed form under the assumption of white-noise excitation. These analytical results are then used in an extensive parametric analysis to investigate the response variation pattern with respect to changes in the parameters of inerter system. In the extremum condition that represents the most efficient parameter set of inertance-mass ratio and damping ratio for response mitigation, an optimal design method is developed by exploiting a performance-demand-oriented design philosophy. The optimal design formulae of the inerter system are derived on the basis of target sloshing height mitigation ratio in analytical form. Moreover, a series of examples are provided to verify the proposed analytical design formulae and design criterion. Based on results from response history analysis under both artificial and natural ground motion records, the design method proves to be effective to meet the desired demand of sloshing height response, while simultaneously reducing base shear force and isolation displacement. The derived analytical design formulae are practical and convenient for preliminary design purposes and substantially explain the mechanism of inerter system for vibration control of liquid storage tank.
•Analytical solutions are derived for tank with inerter isolation system (IIS).•Performance-demand-based design method is proposed using analytical solutions.•Mechanism of IIS is explained for vibration control of liquid storage tank.•Target demand of tank can be achieved by designed IIS.
Multidisciplinary design optimisation (MDO) is a methodology increasingly being used in the preliminary design of aircraft. To limit the computational cost of the procedure, it is generally based on ...coarse models, which do not accurately capture the internal deformation of details with a complex geometry. Therefore, it is not possible to apply constraints in these areas and designers are limited to a conservative pre-sizing of these parts, which are then kept fixed during the optimisation. In this paper we expose the limitations of this approach and present a novel methodology for the preliminary sizing of aircraft, based on global–local MDO. The commonly used coarse model is used together with finer local models, for the parts where additional accuracy is needed. The global–local analysis solves the internal deformation field with sufficient accuracy for the evaluation of local constraints. Furthermore, thanks to the formulation we introduce to compute the coupled sensitivities, the optimiser successfully finds a locally feasible design.
Objective: This article presents an experimental design, the microrandomized trial, developed to support optimization of just-in-time adaptive interventions (JITAIs). JITAIs are mHealth technologies ...that aim to deliver the right intervention components at the right times and locations to optimally support individuals' health behaviors. Microrandomized trials offer a way to optimize such interventions by enabling modeling of causal effects and time-varying effect moderation for individual intervention components within a JITAI. Method: The article describes the microrandomized trial design, enumerates research questions that this experimental design can help answer, and provides an overview of the data analyses that can be used to assess the causal effects of studied intervention components and investigate time-varying moderation of those effects. Results: Microrandomized trials enable causal modeling of proximal effects of the randomized intervention components and assessment of time-varying moderation of those effects. Conclusion: Microrandomized trials can help researchers understand whether their interventions are having intended effects, when and for whom they are effective, and what factors moderate the interventions' effects, enabling creation of more effective JITAIs.
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