Platform Layout Research Articles

CONCEPTUAL DESIGN OF THE SPACE INDUSTRIAL PLATFORM. PROBLEM STATEMENT

The objective of thispaper is to formulate a complex problem of optimizing the design parameters of a space industrial platform at the conceptual design stage. The initial stage of space industrialization was the creation of space industrial platforms in Earth orbit. At present, there are works related to the implementation of a number of technological processes in outer space, which are being studied by scientists and developers. Implementation of unique technological processes in outer space allows forobtaining materials with qualita- tively new characteristics. The peculiarity of designing a space industrial platform is that there are practically no theoretical works related to the choice of platform parameters and the logic of its creation at the conceptual design stage. This stage is characterized by the fact that, apart from the general idea of the platform layout, the expected types of main service systems, some initial data, and the param- eters of the technological processes to be implemented on the p latform, there is little else known. The process of designing a new complex space system, such as an industrial platform, is a multi-level iterative and optimization process, during which its characteristics and mass production are determined and refined. The article analyzes the configurations of existing orbital stations as a prototype of space industrial platforms and determines the ranges of the main parameters of their modules. A set of parameters of technological processes in vacuum and zero gravity conditions that can be implemented on a space industrial platform is formed. The relationship between the technological and basic modules of the industrial platform is shown. The structure of a complex mathematical model of the space industrial plat- form functioning is developed. To ensure successful work at the conceptual design stage, a general statement of the problem of optimizing the mass of the space industrial platform is formulated. The minimum mass and dimensions of the space platform obtained as a result of the optimization are used to further refine the optimal parameters of the platform and, therefore, affect the formation of conditions for the implementation of the technological process. The algorithm of the sequence of operations for solving the problem of optimal design of a space industrial platform is shown in general.

Rapid Diagnostic Platform for Personalized Vitamin B6 Detection in Erythrocytes via PLP Cofactor Mimics.

Personalized assessment of vitamin levels in point-of-care (POC) devices is urgently needed to advance the recognition of diseases associated with malnutrition and unbalanced diets. We here introduce a diagnostic platform, which showcases an easy and rapid readout of vitamin B6 (pyridoxal phosphate, PLP) levels in erythrocytes as a first step toward a home-use POC. The technology is based on fluorescent probes, which bind to PLP-dependent enzymes (PLP-DEs) and thereby indirectly report their occupancy with endogenous B6. For example, low vitamin levels result in high probe binding, yielding a strong signal and vice versa. Antibodies against signature human PLP-DEs were immobilized on microarrays to capture probe labeled enzymes for fluorescent detection. Calibrating the system with defined B6 levels revealed a concentration-depended readout as well as sufficient sensitivity for its detection in erythrocytes. To account for individual differences in protein expression, a second antibody was used to normalize protein abundance. This sandwiched assay correctly reported relative B6 levels in human erythrocyte samples, as confirmed by classical laboratory diagnostics. In principle, the platform layout can be easily expanded to other crucial vitamins beyond B6 via an analogous probe strategy.

MOTIVATION AND SELF-REGULATION OF ENGLISH STUDY PROGRAM STUDENTS IN ONLINE LEARNING

Motivation for online learning is decreased in the past pandemic virus Covid-19. For this reason, self-regulation plays an important role in order to control students’ thoughts and feelings in achieving learning goals. Motivation and self-regulation are aspects necessary in the English learning process. This study was conducted to find out the factors affecting students’ motivation and self-regulation toward online learning. A descriptive qualitative method was used to explain the phenomena through an interview by using open-ended questions to 10 students as a representation. The result shows that there are seven significant elements that give motivational and self-regulated effects to them toward online learning; objectives, task strategy, time management, help-seeking, teaching presence (homogeneous instructional design: structure and layout of OL platforms), interest, and competence. Self-regulation is essential to direct and regulate students’ cognitive processes during online learning. For sure, both cannot be separated from students’ daily life. These attract the attention of the lecturers to the fact that students are not only language receivers but persons with hearts, feeling, and identities. Students and lecturers should work together to integrate those things to achieve successful English learning goals.

Application of QPSO algorithm in layout optimization of construction platform of prefabricated buildings

With the development of the times, the construction industry has become one of the important pillars of the national economy, but the architectural style under the traditional model is no longer suitable for my country's increasing demand for high-quality construction products. my country's construction industry has now entered a high-quality In the stage of development, prefabricated buildings have entered the era of rise. Prefabricated buildings generally adopt standardized design and standardized construction methods. The buildings have the characteristics of green, environmental protection and high efficiency. With the development of prefabricated buildings, the integration of QPSO algorithm and prefabricated technology has become a hot spot in current architectural design. This paper adopts The QPSO algorithm is applied to the layout optimization of the construction platform of the prefabricated building group, and the corresponding construction platform layout optimization scheme is proposed. In view of the weakness of the QPSO algorithm in the single particle search energy in the complex environment, the pheromone mechanism in the ACO algorithm is introduced to obtain The improved quantum particle swarm optimization algorithm, this paper mainly studies the layout optimization scheme of the construction platform of the prefabricated building group, verifies the feasibility of the entire optimization and simulation process, and forms a systematic, scientific and operable platform management process, from theory to practice. Prefabricated assembly Research on platform layout optimization and simulation of modern buildings. The final results of the research show that when the construction cost of the frame component is 50 yuan, the number of iterations of the QPSO algorithm is 196, the number of iterations of the PSO algorithm is 168, and the number of iterations of the GA algorithm is 156, and the number of iterations of the QPSO algorithm is greater than the other two algorithms.

Моделі для оцінки маси космічної індустріальної платформи та її модулів

The goal of this paper is to develop mass models of a space industrial platform and its modules. At the initial stage of development of a new spacecraft, a limited set of basic data is available. For a space industrial platform, they are as follows: the configuration of its main and auxiliary modules, the parameters of the technological processes to be implemented on the platform (the vacuum and the microgravity level, the equipment energy capacity), and the manufacturing equipment configuration. A feature of industrial platform design is that there are few, if any, theoretical works on the choice of platform parameters and the logic of platform conceptual design. In this paper, the design process is considered as applied to the conceptual design stage. This stage is characterized by that nothing is known about the system to be developed except for the general concept of the platform layout, the expected types of the main service systems, some basic data, and the parameters of the technological processes to be implemented on the platform. The process of designing a new complex space system such as an industrial platform is a multilevel iterative and optimization process, during which its characteristics and the mass fractions of its components are determined and refined. The paper presents a mass model of an industrial platform and its modules, in whose development the platform and its components were decomposed to the level of system elements. A statistical analysis of the mass fractions of the onboard spacecraft systems was carried out. The mean values of the mass fractions for the sample of spacecraft under study and their scattering coefficients (the dispersion and the mean square deviation) were determined. For the mean values and the dispersion, 99.9 confidence intervals were determined. Further studies on the design of space industrial platforms are planned to be carried using the mass fractions of satellite systems and the confidence intervals, namely, the minimum and the maximum possible mass for a particular system, determined in this study.

Construction Layout of Stations and its Impact to Train Delays

Abstract The paper focuses on construction layout of railway stations, mainly platforms for boarding passenger trains. Platform layout has significant impact to the operation of trains, because passengers cross some tracks horizontally, when the train boarding is necessary. Horizontal track crossings cause possible dangerous situations from passengers’ point of view as well as operational problems from dispatcher point of view, because other trains have to slow or stop their ride. It may cause delays and it negatively influences timetable planning too. The problem is deeply analysed and described in a case study of Opatov railway station.

A Data-Driven Research of Sales and Purchases on JD.com Platform

Unlike consumers in the mall or supermarkets, online consumers are “intangible” and their purchasing behaviors are affected by multiple factors, including product pricing, promotion and discounts, quality of products and brands, and the platforms where they search for the product. In this research, I study the relationship between product sales and consumer characteristics, the relationship between product sales and product qualities, demand curve analysis, and the search friction effect for different platforms. I utilized data from a randomized field experiment involving more than 400 thousand customers and 30 thousand products on JD.com, one of the world’s largest online retailing platforms. There are two focuses of the research: 1) how different consumer characteristics affect sales; 2) how to set price and possible search friction for different channels. I find that JD plus membership, education level and age have no significant relationship with product sales, and higher user level leads to higher sales. Sales are highly skewed, with very high numbers of products sold making up only a small percentage of the total. Consumers living in more industrialized cities have more purchasing power. Women and singles lead to higher spending. Also, the better the product performs, the more it sells. Moderate pricing can increase product sales. Based on the research results of search volume in different channels, it is suggested that it is better to focus on app sales. By knowing the results, producers can adjust target consumers for different products and do target advertisements in order to maximize the sales. Also, an appropriate price for a product is also crucial to a seller. By the way, knowing the search friction of different channels can help producers to rearrange platform layout so that search friction can be reduced and more potential deals may be made.

Investigating the E-Learning Challenges Faced by Students during Covid-19 in Namibia

Over the past two decades, e-learning has become an increasingly important field of study that has attracted scholarly and policy makers’ attention. Many developing nations have embraced e-learning as a tool to enhance accessilibility and affordability of higher education. During the COVID-19 lockdown period, many universities across the world were forced to embrace online teachning and learning to circumvent lockdowns, social distancing and other public health interventions put in place to contain the spread of the novel coronavirus. Consequently, this study sought to establish students’ experiences with the e-learning mode during the COVID-19 lockdown in Namibia. The paper discusses the results of an online survey of 137 undergraduate students about their experiences using e-learning technologies during the COVID-19-induced university closures. An online survey instrument was created on Google forms and a link distributed to students through WhatsApp class groups. Quantitative data were presented through frequency tables and figures, whilst we adopted thematic content analysis to analyse qualitative data. The results of the survey indicate that mobile devices remained the primary computing device used to access academic information. An analysis of the study results led to the emergence of five themes, viz, e-learning system accessibility, e-learning platform layout, resources to access Internet and network, isolation and home environment that captured student challenges with online classes. This paper argues that e-learning is still faced by a myriad of challenges that need to be addressed if it has to be a success. Furthermore, we advance the argument for mobile learning as a viable option for Africa due to the ubuiquity of mobile devices.

A boarding model for heterogeneous passengers on the platform of high-speed railway station

ABSTRACT Boarding behavior on the platform of high-speed railway (HSR) station, as a critical problem that has not been fully explored and understood, is investigated in this paper. An extended cellular automaton (CA) model is proposed to study the impacts of passengers’ heterogeneities during the boarding process. Some numerical tests are conducted to explore the passengers’ movements and the complex traffic phenomena (e.g., passenger's detour behavior, local congestion and overtaking behavior) on the platform. The numerical results show that the proportion of the passengers carrying luggage has significant impacts on the boarding process (e.g., the degree of congestion, inflow rate at the entrance and route choice). Moreover, the heterogeneous speeds increase the total boarding time and decrease the boarding efficiency comparing with the homogenous speeds. The above results are helpful for the effective management of pedestrian flow on the HSR platform and the optimal design of HSR platform layout.

Multirobot searching method of natural gas leakage sources on offshore platform using ant colony optimization

Natural gas leakage on offshore platforms has a great impact on safety production, and effective and reasonable leakage detection methods can prevent the harm caused by natural gas leakage. This article proposes a method based on ant colony optimization (ACO) for multirobots to collaboratively search for leaking natural gas sources on offshore platforms. First, analyze the structure and environment of the offshore platform, use Fluent software to simulate the diffusion process of natural gas leaked from the platform, and establish a diffusion model of natural gas leaked from various aspects, such as the layout of different platforms, the number of leaked gas sources, and the concentration of leaked gas sources. In terms of multirobot cooperative control, we analyzed and improved the ant colony algorithm and proposed a multirobot cooperative search strategy for gas search, gas tracking, and gas source positioning. The multirobot search process was simulated using MATLAB software, and the robot on the detection effect of multirobots was analyzed in many aspects, such as quantity, location of leak source, and a number of leak sources, which verified the feasibility and effectiveness of the multirobot control strategy based on optimized ACO. Finally, we analyze and compare the two control algorithms based on ACO and cuckoo search algorithm (CSA). The results show that the ACO-based multirobot air source positioning effect is significantly better than CSA.

Application of Analytic Hierarchy process (AHP) in the Layout of Jack-Up Drilling Platform

The scientific and reasonable layout of jack-up drilling platform can improve the efficiency and safety of drilling platform operation. Through the application of analytic hierarchy process (AHP) and the establishment of comprehensive evaluation and analysis model, this paper analyzes the commonly used drilling platform layout scheme and optimizes the scheme to meet operational requirements and to improve the ability of the drilling platform operation.

A novel methodology for the design and optimisation of oil and gas offshore platforms

Oil and gas offshore platforms present similar structural designs and include operations such as separation, compression and pumping. However, they handle large variations in the production of hydrocarbons and water over time. They may also follow different modes of operation depending on the field characteristics and fluid properties. It is therefore not possible to suggest a standard layout of an offshore platform that can be widely implemented in distinct petroleum regions. The oil and gas processing plant should be designed adequately to maximise the hydrocarbon production and minimise the power, heating and cooling demands. The utility plant should be designed appropriately to minimise the fuel consumption and cover the energy needs in all production phases. The present paper presents a generic methodology that addresses these challenges and builds on a combination of process simulation, energy analysis and optimisation routines. Possible platform layouts are sized, evaluated and ranked, based on preliminary estimates of the production profiles and petroleum properties. This methodology is applied to three case studies, derived from actual field data from Norway and Brazil, with different field conditions, fluid compositions (e.g. negligible, medium and high CO2 contents of the well-fluids) and operational requirements (e.g. gas export, injection and lift). The results illustrate the benefits of the proposed methodology, as a comparison with the ‘business-as-usual’ case shows up to 25–30% energy savings and CO2-emissions along the field lifespan.

A Tool for Promoting Responsible Antibiotic Prescribing across Settings and Sectors

ObjectiveTo develop, evaluate, and implement a universal online platform - termed OPEN Stewardship - to promote responsible antimicrobial prescribing (antimicrobial stewardship).IntroductionAntibiotic resistance is a mounting public health threat calling for action on global, national and local levels. Antibiotic use has been a major driver of increasing rates of antibiotic resistance. This has given rise to the practice of antibiotic stewardship, which seeks to reduce unnecessary antibiotic use across different care settings. Antibiotic stewardship has been increasingly applied in hospital settings, but adoption has been slow in many ambulatory care settings including primary care of humans. Uptake of antibiotic stewardship in veterinary care has been similarly limited. Audit and feedback systems of antibiotic use coupled with patterns of antibiotic use and best practice guidelines have proven useful in outpatient settings, but scale-up is limited by heterogeneous systems of care and limited resources.MethodsA multi-sectoral team with partners from Canada, Israel and Sweden is developing a web-based platform for administering antibiotic stewardship across multiple care settings and sectors, for human and animal prescribers. There are several interventions which support behaviour change and can be applied to antibiotic stewardship programs. Systematic reviews have found beneficial effects of numerous behaviour change interventions for optimizing clinical practice such as computerized reminders [1], opinion leaders as champions for change [2], and audit and feedback [3]. A recent Cochrane review [4] found that interventions to enable correct use of antibiotics improved policy compliance, and that enabling interventions that included feedback were more likely to be effective. We will use antibiotic prescribing benchmarking, focused guidelines, and local patterns of antibiotic resistance as key components that can be deployed as feedback through this antibiotic stewardship platform.The OPEN Stewardship platform will be hosted on an AWS cloud-based server using industry standard encryption. The platform will function with a central administrator who will enroll and deliver feedback to participating prescribers. This platform will be evaluated prospectively in two countries (Canada and Israel) to evaluate user experience of the feedback as well as impact on antimicrobial prescribing. The evaluation will include prescribers from both human and animal health. After the prospective evaluation, the platform will be made available online for broad multi-sectoral use.ResultsWe have designed the interface for a web-based platform for antibiotic stewardship which will be used in a multinational prospective primary care stewardship intervention in 2019 and 2020 and subsequently rolled out for broad public use (www.openasp.org). The platform layout can be seen in Figure 1. Data capture for aggregate prescriber level antibiotic use and local guidelines will be possible through both a manual graphical user interface and a dataset template upload. Antibiotic resistance data will be pulled from a companion database (www.resistanceopen.org). Administrators will be able to generate unique feedback forms containing visualizations and snapshots from antibiotic use, guidelines, and antibiotic resistance data (Figure 2). These can then be delivered by email on an individual or scheduled basis for one or multiple prescribers simultaneously. Participating prescribers will also have the option to login to view their own profile and browse antibiotic use, resistance and guidelines.ConclusionsAntibiotic stewardship needs to be adopted in a fashion that is country and context specific and not administered from the top down. With our approach we seek to empower groups from any country or care setting to provide regional and tailored stewardship feedback through an open interface. We have here demonstrated the design of an web-based antibiotic stewardship platform which will be evaluated prospectively and subsequently made available for open and broad multi-sectoral use - in keeping with a One Health approach.

Modelling passenger distribution on metro platforms based on passengers’ choices for boarding cars

ABSTRACTMetro capacity should be further improved with growing demand for metros. For metro lines with high-frequency services, the train dwell time is a determinant of the number of trains per hour. Uneven passenger distribution on the platform may cause a longer dwell time, thereby reducing the capacity. This study analyses the mechanism of the passenger distribution on the platform with regard to which cars of a train passengers choose to board. A model has been developed, considering the origin-destination and waiting time of passengers and the platform layouts of the stations where passengers board and alight. The model was calibrated using loadweigh data, which provides the weight of passengers on each car of a train, on the Hammersmith & City line of the London Underground. The largest difference between the actual and modelled average number of boarders on a car is less than 2 passengers, which suggests the model performs well. The results show, at both stations studied, 44% of passengers in the morning peak chose boarding cars based on the layouts of the stations where they alighted. The results would be useful for metro operation planners and station staff to take measures to manage passenger distribution on the platform.

Optimal energy management of an underwater compressed air energy storage station using pumping systems

The paper is part of the development of a novel underwater isothermal Compressed Air Energy Storage (CAES) system. Compared to conventional CAES plant, the performances of this system only depend on the electrical energy required for a round-trip cycle; performances of each sub-system of the power conversion process takes part of the overall efficiency. Consequently, this work is focused on an optimal energy management of the electrical power conversion system driving the isothermal hydro-pneumatic mechanism enabling the air compression/expansion. After examining inherent characteristics of conversion components challenging the overall conversion efficiency, we propose an efficient platform layout based on the segmentation of the energy conversion multiplying power conversion systems with different power ranges. Then, we establish control laws required by the electrical multi-machines system in order to drive pumping systems closed to their best efficiency points. However, these laws subject the conversion platform to a transient and variable operating needing the design of robust controller structures. Finally, we develop a dynamic reversible modelling of the multi-physic conversion platform along with the control scheme. The layout is modelled on Matlab® Simulink® environment and the paper closes with simulation results. We evaluate the dynamic performances of the compressed air storage system in both storage and production mode. Moreover, the effectiveness of power segmentation for the grid integration of the proposed system is discussed.

Estimation of Passenger Flow for Planning and Management of Railway Stations

Abstract Large scale renovation of rail stations to cater for growing passenger demand has been taking place in various sites in Japan. These projects pose a challenge to researchers to identify suitable technical methods to develop infrastructure layouts that efficiently cater for movement of walking passengers. This paper presents an application in relation to the JR Takatsuki station where there was a narrow island platform catering for large volume of boarding, alighting and transferring passengers. In 2015, the operator has begun expanding the station to alleviate the platform congestion. The objective of the project is to develop a method of forecasting pedestrian flow patterns within a railway station for a proposed new layout of platforms and interconnecting links. The methodology will be demonstrated using Takatsuki station as a case study. The core of the methodology utilizes pedestrian origin-destination pattern to estimate measures of walking effort of pedestrians. In addition to the analytical modelling technique an application of a simulation model is also described. The simulation method is helpful as it is able to provide a visual appreciation of the future operation of the railway concourses. Results indicate that the congestion on the current platform will be alleviated. However, connecting passages to the new platform can become congested because of flow conflicts among transferring passengers and those boarding and alighting.

The structure of conversations on social networks: Between dialogic and dialectic threads

The structure of conversations on social networks may affect the users’ perceptions regarding the informative value of the conversations. Consequently, to draw the maximum benefit from social networks, companies should understand which form these online conversations take. The paper argues that the conversations on social networks can have two forms: (1) dialogic: users interacting among themselves; (2) dialectic: users interacting with the company. Through three empirical studies, the research suggests that users express some preference for dialogic conversations, and young users have a higher tendency than senior users to consider dialogic conversations more informative than the dialectic alternative. These results suggest that social media managers should shape the layout and design of social media platforms to support dialogic conversations, encouraging horizontal interactions among users.

Estimation of train dwell time at short stops based on track occupation event data: A study at a Dutch railway station

SummaryTrain dwell time is one of the most unpredictable components of railway operations, mainly because of the varying volumes of alighting and boarding passengers. However, for reliable estimations of train running times and route conflicts on main lines, it is necessary to obtain accurate estimations of dwell times at the intermediate stops on the main line, the so‐called short stops. This is a great challenge for a more reliable, efficient and robust train operation. Previous research has shown that the dwell time is highly dependent on the number of boarding and alighting passengers. However, these numbers are usually not available in real time. This paper discusses the possibility of a dwell time estimation model at short stops without passenger demand information by means of a statistical analysis of track occupation data from the Netherlands. The analysis showed that the dwell times are best estimated for peak and off‐peak hours separately. The peak‐hour dwell times are estimated using a linear regression model of train length, dwell times at previous stops and dwell times of the preceding trains. The off‐peak‐hour dwell times are estimated using a non‐parametric regression model, in particular, the k‐nearest neighbor model. There are two major advantages of the proposed estimation models. First, the models do not need passenger flow data, which is usually impossible to obtain in real time in practice. Second, detailed parameters of rolling stock configuration and platform layout are not required, which makes the model more generic and eases implementation. A case study at Dutch railway stations shows that the estimation accuracy is 85.8%–88.5% during peak hours and 80.1% during off‐peak hours, which is relatively high. We conclude that the estimation of dwell times at short stop stations without passenger data is possible. Copyright © 2016 John Wiley & Sons, Ltd.

Transfer Efficiency Evaluation Method of Urban Rail Transit Based on the Generalized Cost Function

This paper gives out a method to evaluate transfer efficiency of urban rail transit using a new built mathematical model for transfer streamlines and the generalized cost function. We takeSihuidong Station, one important transfer station in Beijing urban rail transit network, as an example. As for this example, we at first give out basic information ofSihuidong Stationincluding its platform layout, transfer mode and transfer paths. Then the transfer efficiency is evaluated by using the generalized cost function, where we take consideration of some main influence factors such as walking time, transfer waiting time. We also analyze the effects of different crowding levels in peak and off-peak periods.

Supporting the design of railway systems by means of a Sobol variance-based sensitivity analysis

Recently the growing demand in railway transportation has raised the need for practitioners to improve the design of railway systems. This means to identify a configuration of the infrastructure components (e.g. number of rail tracks, type and layout of the signalling system, layout of station tracks) and the operational schedule (e.g. train headways, scheduled dwell times) that improves given measures of performance such as the level of capacity, the punctuality of the service and the energy saving.Planners and designers involved in this process have the hard task of determining sound design solutions in order to achieve certain levels of network performances in a cost-effective way, especially when investment funds are limited. To this aim, a sensitivity analysis can support early decisional phases in order to better understand dependencies between performances and design variables and drive the decisional process towards effective solutions.In this paper, the Sobol variance-based method is applied to this purpose. A practical application has been carried out for a mass transit line in the city of Naples. Such study has investigated how train delays and energy consumption are affected by variations in design variables relative to the operational plan, the signalling system and factors related to the layout of station platforms. Results highlight the ability of this analysis in explaining the effects of different design solutions from a statistical point of view and finding the most influential factors for a given performance. This aspect suggests to practitioners the usefulness of this approach in addressing decisions towards cost-effective interventions.