Ridesourcing systems: A framework and review

The rapid development and spread of information and communication technologies is taking on the character of a global information revolution today. Users have a need for communication services that can be flexibly configured. Next Generation Networks (NGN) - the modern stage of development of telecommunication networks (TCN) - represent a single transport platform on the basis of which various types of services are combined. One of the main aspects that should be taken into account when designing NGN is the provision of appropriate quality of service. With the introduction of multi-service networks, the approach to the task of service level based on the requirements of the users themselves for the quality of services becomes predominant, which requires the improvement of methods of managing the quality of services in TCN. The analysis of the works of domestic and foreign scientists regarding service quality management in TCN indicates the need to improve service quality management methods. It should be noted that in the works on the quality management of telecommunication services (TCS), attention is mainly paid to the technical indicators of the quality of services, while the development of effective methods of taking into account the user's opinion in managing the quality of services is currently relevant. The existing subjective methods of assessing the quality of TCS take into account the quality of the transmitted media information based on expert assessments, but do not provide a full assessment of the quality of the service by the user. The ITU-T recommendations describe different points of view on the quality of service, but do not provide specific methods for evaluating and managing the quality of TCS taking into account the opinion of the user. It is the unsolved task of comprehensive assessment of the quality of services in next-generation TCN that determined the purpose of this work.

Optimization of customer service and driver dispatch areas for on-demand food delivery

We study the impact of yield uncertainty (supply side) and self-interested consumers (demand side) on the inefficiency in the influenza vaccine supply chain. Previous economic studies, focusing on demand side, find that the equilibrium demand is always less than the socially optimal demand because self-interested individuals do not internalize the social benefit of protecting others via reduced infectiousness (positive externality). In contrast, we show that the equilibrium demand can be greater than the socially optimal demand after accounting for the limited supply due to yield uncertainty and manufacturer's incentives. The main driver for this result is a second (negative) externality: Self-interested individuals ignore that vaccinating people with high infection costs is more beneficial for the society when supply is limited. We show that the extent of the negative externality can be reduced through more efficient and less uncertain allocation mechanisms. To investigate the relative effectiveness of government interventions on supply and demand sides under various demand and supply characteristics, we construct two partially centralized scenarios where the social planner (i.e., government) intervenes either on the demand side or the supply side, but not both. We conduct an extensive numerical analysis. This paper was accepted by Yossi Aviv, operations management.

Consumption Externality and Yield Uncertainty in the Influenza Vaccine Supply Chain: Interventions in Demand and Supply Sides

Combined heat and power (CHP), an efficient heating method with cascades use of energy, accounts for approximately 50% of the heat sources in northern China. Many researchers have made significant efforts to improve its energy efficiency and environmental effects with important achievements. Given that the system produces heat and electricity at the same time, this study focuses on the role of CHP in the holistic urban energy system and points out the mismatch between the demand and supply sides of urban energy systems by using the heat-to-power ratio as a parameter. The calculation method and characteristics of the supply side heat-to-power ratio of eight heating methods and the maximum demand side heat-to-power ratio for 19 cities in northern China are displayed. After the analysis, it is concluded that (1) the maximum demand side heat-to-power ratio in the cities varies from 1.0 to 5.9, which is affected by the location and social, economic, and industrial structures. (2) In most of the cities, with the current energy structure, the demand side heat-to-power ratios are always larger than the supply side heat-to-power ratios. (3) The reduction in heating demand, surplus heat recovery, and the use of a highly efficient electric heating method, such as the heat pump, can help solve the mismatch of the heat-to-power ratio between the demand and supply sides. These conclusions can guide the urban energy planning and system construction.

This thesis is concerned with mathematical modelling of consumer durable product form sales over entire product life cycle (PLC). The PLC is defined as the curve which represents unit sales for some product, extending from time it is first placed in market until it is removed. This work was motivated by need to explain many variations of PLC shapes which occur for different products in order to render PLC concept more useful. The thesis deals with dynamic modelling of PLC shapes. This is determined by factors from both demand and supply side of market. As a result, comprehensive modelling of PLCs needs a dynamic characterization of both sides of market and their interactions. Such a model is too complex, and we focus our attention on a simpler case in which only demand side factors are modelled dynamically. As such, thesis' contribution should be viewed as a first step towards building of a more complete model which considers both sides dynamically. In our model, supply side factors which influence demand side are considered exogenous variables and effect of demand side on supply side dynamics is not considered. The traditional PLC concept portrays evolution of sales by four stages:introduction -> growth -> maturity -> decline A alternative representation of PLC concept for consumer durable product forms is developed. The following four phases of PLC are identified by dividing total sales into various components: innovator -> imitator -> repeat -> substitute It is proposed that key time and magnitude scales associated with each of above components of sales determine predominant trends of PLC. Advantages of this new approach include ability to explain variations in PLC shapes and providing a richer base for decision making, since sub-components of total sales are modelled explicitly. Using this new PLC concept and a simple illustrative example, it is shown that most empirically reported PLC shapes can be emulated by proper choice of these time and magnitude scales. Further refinement of this new approach involves more detailed modelling of each of sales components. New models were developed for: first purchase sales of new products (innovator and imitator); repeat purchase sales (replacement and multiple); and, product substitution. A new model for first purchase sales is developed in diffusion paradigm which relates innovative and imitative purchasing behaviour to type of product information required before purchasing. Model analysis revealed model is more flexible than earlier simple diffusion models in terms of emulating bimodal sales curves. Three new models for replacement purchase sales are developed which model mean replacement age (MRA) as changing over time. One model considers MRA to be a function of time, while another represents MRA as a function of price. Yet another model considers changes in forced and induced replacements over time. Two new models for multiple purchase sales are developed which incorporate an upper limit on potential multiple purchases. Four new models for product substitution are developed within diffusion paradigm. New elements incorporated into these models include explicitly modelling both forced and induced substitute purchases, and substitute decisions dependent on age of consumer's currently owned unit of incumbent product. The models presented represent new theoretical contributions. While empirical testing of these models is performed with data available, limited nature of this data does not permit complete validation of these models. The results of testing first purchase model are encouraging with model fitting data better than previous similar models. Unfortunately data available for testing replacement purchase models is not of sufficient quality to properly validate new models. In case of multiple purchases and product substitution models, data for only one product was available. The results for both cases are tentatively encouraging, with models fitting data quite well, though addition data is again needed for both cases.

With the growing applications of big data and artificial intelligence, the quality of the service is an outcome of the quality of the data. Nevertheless, there is still a significant lack of data that has practical application value. To solve these problems, we propose SODAS (Smart Open Data As a Service) as a novel open data platform for efficient data sharing and utilization. We first analyze the major problems in the legacy CKAN and then draw up their solutions through core strategies. We next define four components and nine function blocks of SODAS for each core strategy. As a result, SODAS drives Open Data Portal, Open Data Reference Model, DataMap Publisher, and ADE Provisioning (Analytics and Development Environment Provisioning) by connecting the defined function blocks. We confirm that each function works correctly through the SODAS Web portal and apply SODAS to actual data distribution sites to prove its efficiency and practical use. SODAS is the first open data platform that provides secure interoperability between heterogeneous platforms based on international standards and enables domain-free data management with flexible metadata.

ABSTRACTThis study develops a macro-econometric model for the Namibian economy. This macro-econometric model estimates both the demand and supply sides of the Namibian economy. This model incorporates the price sector, in order to serve as a link between the supply and demand sides of the economy. The model consists of behavioural equations, linked by identities and definitions. These behavioural equations were estimated and simulated individually. They were then combined together to form a full macro-econometric model of the Namibian economy. The full macro-econometric model was closed using two models. The first model activates the supply side and marginalises the demand side. The second model is demand side orientated, which activates the demand side and marginalises the supply side. The results indicate that the estimated values closely approximate the actual values. This macro-econometric model can be used to apply policy simulations, in order to determine appropriate economic policies for Namibia.

Accountability and transparency have been on the top of lists of the agenda about local governance. Unfortunately, a significant number of studies have tended to view accountability through the traditional model of public administration (supply side of accountability) at the expense of the demand side of accountability. Based on the experience with decentralization in Tanzania for the past four decades, this article argues that both the demand and supply sides are important for effective service delivery by local governments. In this arrangement, the fundamental principle of democracy is attained when citizens have the right to demand accountability and public officials are held accountable. The demand side, which is bottom up driven by non–state actors, or the supply side, which encompasses legal and fiscal governmental checks and balances may lead to effective local good governance. This article is based on these assumptions and therefore attempts to discuss the main avenues and challenges for exercising effective supply and demand sides of accountability in local governments in Tanzania. The study seeks to answer the question of how the demand and supply sides of accountability have been implemented in Tanzania, regarding local governments.

Economic analysis of grid integration of variable solar and wind power with conventional power system

Purpose The purpose of this research is first to examine the extent to which renewable energy providers (supply side) add value to their consumers (demand side) and how these perceive value-adding when acquiring these solutions. Second, the key challenges in supplying renewable energy solutions and how value-adding is manifested for the demand side are investigated. Third, the study ascertains the key resources needed to provide value (supply side) and how the consumption experience could be enhanced (demand side). Design/methodology/approach Semi-structured interviews were conducted with representatives from the supply and demand sides of renewable energy in Vietnam; the data were analysed through qualitative content analysis and data structure. Findings The analysis underlines commonalities and differences between the two participating groups. For instance, whereas members of the supply side perceive committing to higher levels of service or providing expert advice as fundamental opportunities to add value, those on the demand side value add-ons, including detailed instructions and consultations, together with the possibility to purchase quality products. Originality/value In embracing the underpinnings of the diffusion of innovations theory, this study makes various contributions to the business and renewable energy literature in emerging markets. Importantly, a conceptual framework with implications for practitioners and researchers was developed. This framework is founded on 21 conceptual dimensions revealed in the analysis, including the action-oriented and service-oriented, which help discern tangible and intangible ways to add value from the supply side. Relationships between the analysis and the theory's principles were also uncovered.

Research is rich in analyzing performance and quality of city services (e.g., the frequency and timeliness of the), while the quality of experience is usually overlooked. This research combines the quality of service and the quality of experience into a single multi-faceted framework. The proposed framework incorporates visualizations and implements urban analytics to compare QoS and QoE. Discrete event simulations and Markov Chain Models are created to model city services’ behavior and simulate events. At the same time, resilience metrics are used to evaluate the quality of the service. Data mining of social media, natural language processing, and emotion analysis techniques are employed to measure the QoE. The framework is implemented to analyze how services react to different types of service disruptions (e.g., weather, maintenance, attacks) through time and their effect on customers. This research’s main findings are related to the differences in resilience of the services during disruptions, while QoE reveals additional issues associated with their use. The proposed framework is illustrated through transportation services, providing insights on their performability and customer’s perception of the service. Future work involves collecting data on other services to test the framework further, as well as improving the layers of superimposed data for explorations and visualizations, thereby creating a decision-making tool for stakeholders.

PurposeThe aim of this study was to analyse the different barriers to accessing healthcare, social services and long-term care among older adults.MethodsA systematic review and narrative synthesis were conducted to analyse barriers to accessing healthcare, social care and long-term care services among older adults. We followed the PRISMA guidelines. A systematic search was conducted in the PubMed, Scopus, and Web of Science databases.ResultsSeventenn studies were included in the systematic review. Seven articles were systematic reviews, six were scoping reviews, two were literature reviews, one was a rapid review and the last one was an integrative review. The results show that the different types of barriers that hinder access to services for older adults are, on the demand side, socioeconomic factors; and on the supply side, geographical factors. Community factors and the digital divide are on both the supply and demand side. Interaction between barriers should be considered.ConclusionAdequate access to social and health services is crucial for the health and well-being of older adults and to guarantee equity in health. In summary, access to health services for older adults is determined by a heterogeneous interaction of these factors, on both the demand and supply side. Overcoming these barriers requires a comprehensive approach involving the collaboration of governments, healthcare providers, communities and older adults themselves.

Extreme events bring great challenges to the safety and resilience of a distribution network, which makes it difficult for traditional static resources to provide enough operation support. The continuous enrichment of spatial‐temporal flexibility resources on both the power demand and supply sides provides a new idea for the dynamic dispatching of distribution network. This paper proposes a spatial‐temporal migration method of mobile power sources (MPSs) on the supply side and internet data centres (IDCs) on the demand side, based on the power‐transportation and power‐computation network coupling models respectively. Then, the dynamic dispatching potential of MPSs and IDCs is evaluated, and the dispatching models against extreme events of MPSs and IDCs are established. With the objective of maximizing system resilience and minimizing dispatching costs, an optimization model considering spatial‐temporal migration of data loads and MPSs dynamic dispatching strategy is formulated. Finally, the proposed method is tested in the modified IEEE 33‐node test system and IEEE 69‐node test system, and the economy and resilience enhancement are verified with comparison of different dispatching schemes.

One of the greatest challenges to the sustainability of the winter tourism sector is climate change. Studies examining the implications of climate change for the ski tourism industry have mainly focused on vulnerability of the supply side (i.e. ski area infrastructure and operators) with limited attention given to the demand side (i.e. how tourists will respond to changing climate and ski conditions). A more holistic understanding of how the winter tourism marketplace may evolve under a changed climate is required for managers and communities to develop and plan specific adaptation strategies. Using a systems approach this study examines climate change vulnerability of both the supply and demand sides of the US Northeast ski tourism sector (i.e. a marketplace of some 103 ski areas across the states of New York, Vermont, New Hampshire, Maine, Massachusetts, Rhode Island and Connecticut). Multiple methods were employed including a climate change analogue (demand and supply side), future climate change and operations modeling (supply side), and a skier survey (demand side). Findings reveal a complexity of interacting and opposing impacts including the projected contraction northward of viable ski areas. In response to projected ski area closures in the region, demand for skiing opportunities is not likely to decrease proportionally. Ski areas that are able to remain operational under changed conditions should plan for a possible market-shift (i.e. spatial substitution) and may expect crowding issues and residual development pressure in association with the concentration of ski areas in fewer climate-advantaged regions.