Supply Characteristics Research Articles

Household car-ownership in a world of constant change: The continued influence of traditional variables and the rising influence of emerging mobility scenarios

AbstractEmerging modes (e.g., cargo bikes), mobility solutions (e.g., shared mobility services) and policy measures (e.g., the reduction of public parking spaces) are envisioned to reduce private car-ownership. However, the development of disaggregate car-ownership models dealing with them, which can be integrated with transport simulation systems, is still missing. Therefore, this study aims to fill this gap through the development of household car-ownership models, focusing on the cities of Madrid, Regensburg and Leuven. These cities correspond to distinct urban contexts in Europe. Models based on a representative individual as well as based only on household variables are explored, to check whether the latter shows congruence with the former and can achieve good summary statistics with lower data requirements. Furthermore, such models with only household-level variables are also found to be useful in ascertaining the impact of small-scale shared services. The estimation results show the influence of socio-demographic characteristics, mobility patterns, mobility tool ownership, transport supply and urban characteristics. Discussions are included on behavioural and policy insights. For example, cargo bike ownership and the presence of shared services support in car-ownership reduction. Furthermore, public parking spaces have a significant impact on single car-ownership in Madrid, but not on multiple car-ownership. Besides, the contrasting effects found for the mobility rates in Madrid and Regensburg convey the importance of urban design contexts. The contributions from this study enable to estimate the household car-ownership with the consideration of emerging mobility scenarios, and to devise policies to reduce private car-ownership and promote sustainable urban mobility.

Improving the mechanical characteristics of water supply and sewerage pipes in urban areas

Improving the mechanical characteristics of water supply and sewerage pipes in urban areas

Supply Chain Analytics, Definitions, Characteristics and Applications: A Systematic Literature Review

While there is a high uptake of BDA in the realm of supply chain management, in the view of automation supply chains and improving their value proposition by providing more accurate data for demand forecasting. There are material knowledge gaps on the SC-specific analytics applied to match demand, albeit the existing knowledge could be more amorphous. From this backdrop, the study endeavored to analyze extant literature within the ambit of BDA to unpack the current trends and possible future research directions to foster the application of BDA in SC contexts. The study adopted a systematic literature review of the extant literature published between 2014-2023. The study adopted the five-stage iterative procedure used in the systematic review methodology. The review's findings depict extensive use of big data analytics in matching demand and supply and supply chain optimization. The findings of this study adduce almost non-rebuttable evidence that big data analytics can be applied in procurement, inventory control, logistics, and order processing. Under the auspices of BDA is the SCA. Arguably, extant research has demonstrated the capability of SCA in mitigating contemporary SC risks such as mismatches between demand and supply, sub-optimal SCs, and underutilization of the supply chain infrastructures at the cusps of various echelons.

Modeling Supply Air Jet of Split Air Conditioner Based on Abramovich Jet Theory and Bayesian Markov Chain Monte Carlo Algorithm

Aim: This study aims to develop supply air jet models for split air conditioners. Background: Designing and operating an air conditioning system based on the unique characteristics of the supply air jet is essential to control the draft risk. Motivation: Due to the distinct differences in air supply characteristics of the split air conditioners caused by the intermittent operation and the complex design of supply air outlets, the existing supply air jet models designed for central air conditioning systems are unsuitable for split air conditioners. Significant results: In this study, models for the trajectory position, velocity, and temperature of the supply air jet for split air conditioners are established based on the Abramovich jet theory and Bayesian Markov Chain Monte Carlo (MCMC) algorithm. The effectiveness of the proposed models is demonstrated via comparison with the training dataset from the experimentally validated Computational Fluid Dynamics simulation of a split air conditioner. For the model testing dataset, the RMSEs of trajectory position, velocity, and temperature are 0.01 m, 0.09 m/s, and 0.09 °C, respectively, with a low supply air velocity and 0.01 m, 0.25 m/s, and 0.03 °C with a high supply air velocity. The proposed models of velocity and temperature of the supply air jet are general for various supply air conditions, while coefficients in the trajectory position model of the supply air jet need to be recalibrated with the proposed Bayesian MCMC algorithm for different supply air conditions. The proposed models provide valuable guidance for the operation of split air conditioners.

Spatiotemporal Evolution Characteristics and Multi-scale Spatial Balance and Matching Analysis of Ecosystem Service Supply and Demand in Hubei Province

In-depth study of the spatiotemporal evolution characteristics of ecosystem service supply and demand and their multi-scale spatial matching patterns is crucial to achieving effective management of ecosystem services and formulating scientific ecological protection plans. Investigating the Hubei Province as a research region, this study employed diverse ecological models, such as InVEST, based on multiple data sources encompassing land use, meteorological conditions, and socio-economic factors. The objective was to quantitatively assess and spatially characterize the supply and demand dynamics of four ecosystem services-namely, carbon storage, water yield, soil conservation, and food provision-within the Hubei Province. A comprehensive analysis was conducted on the spatiotemporal evolution characteristics of ecosystem service supply and demand, as well as the supply-demand ratio of ecosystem services at different scales, from 2000 to 2020. The bivariate Moran's I module in GeoDa was used to further explore the changes in the spatial matching patterns of four ecosystem services supply and demand between 2000 and 2020, as well as the differences in the spatial matching patterns of four ecosystem services supply and demand at different scales in 2020. The research results indicated that： ① Between 2000 and 2020, the total supply of the four ecosystem services in Hubei Province exhibited an overall increasing trend. Regarding total demand, all services, except for food supply, showed a growing trend. Except for soil conservation services, the other three services were in a state of oversupply. ② Except for soil conservation services, the other three services exhibited a polarized pattern with lower urban-rural supply-demand ratios and higher non-urban-rural supply-demand ratios. This pattern deepened progressively over the study period. ③ Significant regional variations were observed in the spatial matching of supply and demand for the four ecosystem services. ④ There were notable differences in the balance and matching of ecosystem service supply and demand at different scales. The research results can provide scientific basis for promoting the optimization of the supply and demand pattern of ecosystem services in Hubei Province and formulating more accurate and detailed ecological protection plans, promoting sustainable development in Hubei Province.

Analysis of energy storage optimization configuration based on the new rural energy system

Abstract Due to the influence of weather factors, distributed photovoltaics exhibit a characteristic of high output in the afternoon and low output in the evening, resulting in an imbalanced supply and demand of rural electricity, a low utilization rate of distributed photovoltaics, and slow progress in poverty alleviation in rural areas. This paper proposes a distributed energy storage optimization configuration model that takes into account various factors such as rural household electricity consumption, aquaculture load power supply characteristics, distributed photovoltaic output characteristics, and the lease period of distributed energy storage box battery modules. The optimization objective is to maximize the benefits of distributed photovoltaic systems in rural areas and minimize the investment costs of farmers, with distributed photovoltaic capacity and the lease period of distributed energy storage as decision variables. Further, considering the problem of the Slap Swarm Algorithm being prone to falling into local optima when solving the model, a set of optimal points is introduced to initialize the population and improve the algorithm’s global search ability. Finally, the effectiveness of the proposed model was verified through a comprehensive example of rural distributed photovoltaics.

Micro water energy harvesting system based on tubular triboelectric nanogenerator

Abstract Constructing a micro-water energy-harvesting system for the power supply of micro-nano sensors in pipeline liquid transmission networks is of great significance. In this study, a micro water energy harvesting system based on a tubular triboelectric nanogenerator was designed, which achieves efficient energy harvesting and conversion by directly collecting the charge of the friction layer without the electrostatic induction effect. First, the working principle of the liquid-solid triboelectric nanogenerator is analyzed based on multi-physic coupling, and the potential distribution in the charge transfer process is analyzed. Second, the effects of liquid flow, pipe length, inner diameter, and material on the output characteristics of the triboelectric nanogenerator were investigated. Finally, the load power supply characteristics of the triboelectric nanogenerator were presented. The output characteristics of the liquid-solid triboelectric nanogenerator were proportional to the flow rate and inversely proportional to the inner diameter of the pipe. The output power of the liquid-solid triboelectric nanogenerator can be charged and stored by the capacitor through the rectifier bridge, and at least 30 LED lamp beads can be driven at a flow rate of 650 ml·min-1. This research has the potential to be applied to the construction of self-powered liquid-state monitoring intelligent sensors in pipeline networks.

Extended pancreatic neck transection during laparoscopic pancreatoduodenectomy can benefit postoperative short-term outcome without influence on remnant pancreatic function: A propensity score-matched comparison in high-volume center

IntroductionDue to the anatomical characteristics of pancreatic duct alignment and pancreatic blood supply, transecting pancreatic neck more to left (EPNT) could theoretically reduce the incidence of postoperative pancreatic fistula (POPF) by leaving the pancreatic duct central in transverse section and the pancreatic stump enough vascularization. Studies revealed that EPNT contributed to the prevention of POPF after pancreatoduodenectomy (PD). However, the impact of EPNT on the remnant pancreatic function was not investigated. Thus, we conducted this study to further explore the impact of EPNT on patients who underwent laparoscopic pancreatoduodenectomy (LPD), including both short-term and long-term prognosis. Material and methodsA retrospective cohort study with 1:1 propensity score-matched comparison of extended and conventional pancreatic neck transection (EPNT vs. CPNT) was conducted in a high-volume pancreatic surgical center. Primary outcome was clinically relevant POPF (CR-POPF), secondary outcomes were textbook outcome (TO), overall and pancreas specific complications, postoperative new-onset diabetes mellitus, and pancreatic exocrine dysfunction. Risk factors for CR-POPF and TO had also been tested by logistic regression analysis. Results233 patients were involved, 153 in EPNT group and 80 in CPNT group. The independent risk factors for CR-POPF were higher BMI (P=0.035), CPNT (P<0.001), perioperative blood glucose changes (P=0.016), and postoperative serum amylase (P=0.026). The predictors for TO were female (P=0.035), no transfusion (P=0.017), EPNT (P<0.001), and perioperative blood glucose changes (P=0.023). After matching, there were 61 patients in each of the two groups. Lower rate of CR-POPF (11.5% vs. 31.1%, P=0.008), lower rate of Clavien-Dindo≥3 complications (6.6% vs. 21.3%, P=0.019), and higher rate of TO (83.6% vs. 55.7%, P<0.001) occurred in EPNT group. The incidence of postoperative new-onset diabetes mellitus and pancreatic exocrine dysfunction did not have statistically significant differences between the two groups. ConclusionEPNT during LPD benefits postoperative short-term outcomes without influence on remnant pancreatic function. Randomized controlled trial with higher level of evidence is needed for further confirm.

Demand and supply characteristics, supply chain strategy and business performance

This study sought to examine the effect of demand and supply characteristics on business performance. This study adopted explanatory research design. This study adopted explanatory research design. A Purposive sampling (also known as judgment, selective or subjective sampling) sampling technique was used to obtain a total sample size of 252. A primary research instrument was used where questionnaires were adopted from literature. This study concludes that demand and supply characteristics have a positive and significant influence on supply chain strategy. Supply chain strategy has a positive and significant influence on business performance. Demand and supply characteristics have a negative but insignificant influence on business performance. Supply chain strategy positively and significantly mediates the relationship between demand and supply characteristics and business performance. The study is to help the management of organizations to develop the best strategy that will suit their demand and supply so that they can enjoy economies of scale.

Study on the ecosystem service flow based on the relationship of between supply and demand in Yangtze River Economic Belt

Ecosystems supply goods and services to humans and are the basis for sustainable development of human society. The study of the supply of ecosystem services and the demand and consumption of ecosystem services by human society, and the analysis of the supply and demand characteristics and flow relationships of ecosystem service flows are of great significance for the management of regional ecosystems and the development of ecological compensation. Taking the Yangtze River Economic Belt as an example, this paper calculates the supply and demand indices of ecosystem services in 2015 and 2020, and determines the ecosystem spatial flow paths and flow volumes from the ecosystem supply area to the demand area based on various methods and models such as the minimum cumulative resistance (MCR) model and distance decay model. The results indicate that 1). In 2015 and 2020, the supply and demand of ecosystem services in the Yangtze River Economic Zone show an increasing trend numerically, and there is spatial heterogeneity in the spatial distribution. In terms of ecosystem service supply per unit area, the midstream region is higher than the upstream and downstream regions. In terms of the demand for ecosystem services per unit area, the downstream is higher than the midstream and upstream. 2). From the supply-demand balance of ecosystem services in the Yangtze River Economic Zone, the midstream region is mainly the area of surplus supply of ecosystem services, and the downstream region is mainly the area of deficit supply. From 2015 to 2020, the number of areas with balanced supply and demand of ecosystem services in the Yangtze River Economic Belt decreases and the number of areas with unbalanced supply and demand increases, which is related to the changes in the level of economic development and land use patterns. 3). The flow of ecosystem services in the Yangtze River Economic Belt shows an increasing trend, from 726.59 billion yuan in 2015 to 1,450.54 billion yuan in 2020, with Jiangxi Province being the main ecosystem service supply area and Zhejiang Province being the main ecosystem service demand area in the Yangtze River Economic Belt.

The Effects and Risk Factors of Femoral Neck Shortening after Internal Fixation of Femoral Neck Fractures.

Internal fixation has been established as a treatment of choice in relatively young patients with femoral neck fractures. Due to the characteristics of femoral neck anatomy and blood supply, complications such as malunion, nonunion, avascular necrosis, and femoral neck shortening can occur after internal fixation of femoral neck fractures. Unlike other complications such as avascular necrosis or nonunion, femoral neck shortening has not been relatively well studied. This study aimed to investigate the risk factors and clinical outcomes of femoral neck shortening after internal fixation of femoral neck fractures. From June 2012 to July 2022, among 102 patients who underwent internal fixation of femoral neck fractures, 94 patients who met inclusion and exclusion criteria were retrospectively analyzed. Internal fixation of the femoral neck was done with cannulated compression screws or a femoral neck system. Patients were divided into 2 groups; femoral neck shortening (≥ 5 mm) and no shortening (< 5 mm) according to measurement on follow-up hip anteroposterior (AP) simple radiographs compared with postoperative hip AP simple radiographs. Demographic and radiographic data were compared between the 2 groups. The modified Harris Hip Score (mHHS) and a visual analog scale (VAS) were used to evaluate the clinical outcomes. Among 94 patients, femoral neck shortening was observed in 33 (35.1%). In chi-square test, Pauwels angle, Garden type III or IV (displacement), and cortical comminution were significantly correlated with neck shortening (p < 0.05). In the multifactorial logistic regression test, cortical comminution was significantly correlated with femoral neck shortening (p < 0.01). The shortening group showed significantly lower clinical scores in terms of mHHS and VAS (p < 0.01). The femoral neck shortening group showed significantly lower clinical scores of mHHS and VAS than the no-shortening group. The presence of cortical comminution in preoperative hip computed tomography is a risk factor of femoral neck shortening after internal fixation of femoral neck fractures.

Supply chain risk management (SCRM) process: an analysis in the aerospace industry

PurposeThe study analysed the aerospace industry, a traditionally important sector for the topic of risk management, from three complementary perspectives: the supply chain risks present in the sector, the mitigation strategies adopted to face them, and the characteristics (dimensions) observed in the SCRM process of aerospace companies.Design/methodology/approachThe research employed a quali–quantitative method: a survey was carried out, followed by interviews with professionals from companies belonging to different tiers of aerospace supply chains. Interviews helped to interpret the survey data and understand in more detail risk management in aerospace companies.FindingsThe study presents a panorama of the aerospace industry in terms of risk management. The sector’s turbulent environment is described as well as the strategies to prevent, minimise or postpone the impact of supply chain risks. In particular, ten dimensions that have been identified in the SCRM process of aerospace firms are discussed. These characteristics influence the objectives of this process and are related to resources, roles and responsibilities, incentives, development of competences and skills, scope (internal and external) and approaches to integrate decisions and actions in the context of the supply chain.Originality/valueArticles that address the SCRM process usually focus on the process steps, whereas this study investigated dimensions that transcend these steps but whose discussion in the literature is still fragmented. It also analysed a reference sector for the topic from a broader perspective than others available in the literature (supply chain risks, mitigation strategies and characteristics of the SCRM process). Supply chain members with relationships with each other were investigated, a desirable approach for SCRM but still under-explored. The study also answers calls for industry-specific studies and research on emerging countries.

Data Monetization Strategies: The Construction Industry Market Analysis

Data monetization is leveraging data to obtain economic benefits. In the context of Big Data Analytics (BDA), data serves as a fundamental asset, enabling the transformation into valuable insights throughout various construction phases. Unfortunately, there is lack of studies focusing on data monetization within the construction industry, given the unique supply and demand characteristics among construction stakeholders. This study aims to address the objective of identifying data monetization strategies applicable to the construction industry, particularly for data sellers and data buyers. Data was gathered through a quantitative survey among 100 construction practitioners in Malaysia, encompassing developers, contractors, consultants, government agencies, technology providers, and academia. Respondents were further categorized into data sellers and data buyers. The data were analyzed using mean analysis, t-test and Spearman's rank correlation coefficient. The study identified six data monetization strategies, comprising 19 determinants. The analysis revealed high preference on all data monetization strategies and moderate differences in the preferred strategies between data sellers and buyers. Significant differences were found in 3 determinants which are (1) trading data to facilitate decision-making, (2) trading data for construction reports, benchmarks, and indices, and (3) selling visualized data on real-time platforms. The t-test indicated that data sellers are more inclined towards the three strategies for effective monetization. Furthermore, Spearman’s correlation coefficient revealed the 3 determinants also positively influence another 3 determinants of (1) data wrapping to reflect better service from data provider, (2) buying raw data with its inherit information and (3) monetizing internal data to optimize organization’s work process. The insights enable stakeholders to implement mechanisms that foster data monetization within project cultures accelerating BDA undertakings. Future recommendations include using larger sample sizes to enhance generalizability and to explore more areas such as construction contracts, cost, health, and safety.

Control of DC–DC Boost Converter Based on Optimal Gas Supply Characteristics of Fuel Cell System

Control of DC–DC Boost Converter Based on Optimal Gas Supply Characteristics of Fuel Cell System

Platform integration in ride-sourcing markets with heterogeneous passengers

This paper explores the impacts of a novel business model termed platform integration, which enables passengers to simultaneously request on-demand rides from multiple ride-sourcing platforms via a third-party integrator. In particular, we employ an equilibrium model where passenger demand and driver supply are endogenously dependent on the prices and wages that emerge from the competitive interaction between two platforms, with and without an integrator. A Hotelling model is adopted to characterize passengers’ heterogeneity in service preference for different platforms. We employ the concepts of a Nash equilibrium and a shared monopoly to analyze equilibrium outcomes that can arise in various settings of demand and supply characteristics with and without platform integration. We find that how the platform should adjust its price and wage at Nash equilibrium as potential demand increases is affected by the nature of supply. We also find that the profit at Nash equilibrium can increase or decrease in supply capacity depending on the competitive situation of the platforms. We build on these equilibrium results to analyze how platform integration affects the platform’s decision-making of price and wage, and market performance. We find that platform integration can increase platform profit but reduce driver income, and may hurt passengers who have a strong preference for one certain platform, especially in the case of a less heterogeneous supply.

Characteristics of the fish food supply of the Uglich reservoir

The work on assessing the feed base of the Uglich Reservoir was carried out within the framework of annual monitoring studies by the Branch for Freshwater Fisheries of the Federal State Budgetary Scientific Institution “VNIRO” (VNIIPRH). Samples were taken in July 2021 and 2022 on three sections. During the year, 10 samples of zooplankton and benthic invertebrate communities were collected and processed. The purpose of the study is to evaluate the fish food supply of the Uglich Reservoir according to the indicators of zooplankton and benthic invertebrate communities in the period 2021–2022. The tasks of the study: to determine the number and biomass of zooplankton of the Uglich Reservoir in 2021–2022; to determine the number and biomass of benthic invertebrate communities of the Uglich Reservoir in 2021–2022. The Uglich Reservoir belongs to the Upper Volga cascade of hydro nodes. Located in the territory of two regions and having a length of more than a hundred kilometers, it has differences in water temperature and oxygen content in the water by reaches. Oxygen conditions in 2021 in the bottom layers, and in 2022 — both in the surface and in the bottom horizons, were unfavorable: deviations from the water quality standard were observed. The studies showed that the productivity of the Uglich Reservoir also varies by reaches. The maximum indicators of zooplankton development were observed in the channel part of the Upper reach of the reservoir. During the observation period (with incomplete determination), 21 taxa of planktonic organisms were recorded, including: Rotifera — 5, Cladocera — 12, Copepoda — 3 and Bivalvia — 1 species. In the composition of the plankton fauna, Cladocera dominated in number and biomass. The benthic invertebrate communities of the Uglich Reservoir is mainly represented by oligochaetes, chironomid larvae and bivalve molluscs. By the magnitude of the summer biomass of zooplankton and benthic invertebrate communities, in accordance with the generally accepted classification of Pidgayko (1968), the Uglich Reservoir in 2021 can be assessed as a high-feed reservoir, and in 2022 — as a medium-feed reservoir.

Research on the optimal operation of a prosumer micro energy network centred on data centres

AbstractAs the share of intermittent and fluctuating renewable energy sources in the power system continues to increase, demand‐side resources must be utilized to enhance the real‐time balance of power generation and supply. Data centres, as typical energy‐intensive loads with bidirectional supply and demand characteristics, are crucial demand‐side resources. However, their operation is complex, making reliable regulation difficult. This paper establishes a refined process‐level load model for data centres by considering the temporal and spatial shifting characteristics of computational loads, effectively reflecting the intricate interactions between these loads and servers. Based on this model, a micro‐energy network is constructed that integrates renewable energy access and waste heat recovery from the data centre. This network also participates in carbon emission trading and green electricity certificate trading markets, applying an interaction mechanism. By considering data interaction and power sharing among multiple micro‐energy networks, the alternating direction method of multipliers algorithm is used to solve the system‐distributed optimization problem in two stages. This approach results in an optimal energy management scheme that simultaneously reduces total operation costs and carbon emissions.

Study on green power supply modes for heavy load in remote areas

In this study, the present situation and characteristics of power supply in remote areas are summarized. By studying the cases of power supply projects in remote areas, the experience is analyzed and described, and the applicability of related technologies, such as grid-forming storage and power load management, is studied, including grid-connection technologies, such as grid-forming converters and power load management. On this basis, three power-supply modes were proposed. The application scenarios and advantages of the three modes were compared and analyzed. Based on the local development situation, the temporal sequences of the three schemes are described, and a case study was conducted. The study of the heavy-load power supply mode in remote areas contributes to solving the problem of heavy-load green power consumption in remote areas and promoting the further development of renewable energy.

Supply and demand of lithium in China based on dynamic material flow analysis

Lithium demand in China has grown rapidly with the popularization of computer, communication and consumer electronic (3C) products, electric vehicles (EVs), and other products. As an important part of the global processing of lithium products, China still relies on importing a vast majority of raw lithium materials, which significantly affects the supply fulfillment of China's lithium market. Therefore, this study used MFA to analyze the supply and demand characteristics of China's lithium trading market from the trade material flow between 2000 and 2021 and industrial material flow between 2017 and 2021 by quantizing trade and industry data. The results showed that the import of lithium in China is mainly concentrated on lithium carbonate, which is the raw material for power batteries, and the import of lithium accounts for 72.5 % of the consumption in China, about 75.2 % of carbonate lithium is used for batteries. Given the expanding EV market, the demand for lithium in China increases rapidly. In addition to a stable supply of lithium imports, secondary lithium recovered from EoL batteries is expected to become an important lithium supply source.

Design of a Portable Emergency DC Power Supply

Abstract In recent years, wireless or handheld devices have become increasingly widely used, especially in areas such as environmental monitoring and the Internet of Things. However, due to environmental conditions, they cannot rely on the power grid to provide electricity, and energy supply has become a key issue that restricts the deployment and operation of such devices. This article introduces the method and principle of applying a microcontroller control system to a portable emergency DC power supply, and proposes a method for a portable emergency DC power supply with adjustable and stable output. The output voltage can be adjusted in steps of 0.1-15V. This adjustable portable emergency DC power supply not only has the advantages of small volume and low loss of switch mode power supply, but also has the advantages of small output voltage ripple and good output characteristics of linear power supply. It has certain research significance and practical value.