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11.
Elham Shafiei Gol Mari-Klara Stein Michel Avital 《The Journal of Strategic Information Systems》2019,28(2):175-195
Crowdwork, a new form of digitally mediated employment and part of the so-called gig economy, has the capacity to change the nature of work organization and to provide strategic value to workers, job providers, and intermediary platform owners. However, because crowdwork is temporary, large-scale, distributed, and mediated, its governance remains a challenge that often casts a shadow over its strategic value. The objective of this paper is to shed light on the making of value-adding crowdwork arrangements. Specifically, the paper explores crowdwork platform governance mechanisms and the relationships between these mechanisms and organizational value creation. Building on a comprehensive review of the extant literature on governance and crowdwork, we construct an overarching conceptual model that integrates control system and coordination system as two complementary mechanisms that drive crowdwork platform governance effectiveness and the consequent job provider benefits. Furthermore, the model accentuates the role of the degree of centralization and the degree of routinization as critical moderators in crowdwork platform governance. Overall, the paper highlights the potential of crowdwork to contribute not only to inclusion, fair wages and flexible work arrangements for workers but also to organizations’ value and competitive edge. 相似文献
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13.
《International Journal of Hydrogen Energy》2021,46(72):35525-35549
Hydrogen is seen as a promising and inevitable energy carrier in the transition towards a carbon-free energy era. This study reviews the potential for carbon-free hydrogen production, utilisation and exportation from the State of Qatar. The study aims to introduce a roadmap for current and future exploration of carbon-free hydrogen production and exportation from Qatar, for which an assessment of several available alternatives for the production of hydrogen in Qatar is performed. These alternatives include the use of natural gas as a feedstock for hydrogen production through steam methane reforming (SMR), solar integrated steam methane reforming with carbon capture, as well as the possibilities for hydrogen production from electrolysis using renewables and ammonia as another intermediate. The potential of each alternative is reviewed based on selected technical, economic and environmental criteria. The findings of this review study indicate that the production and exportation of blue ammonia currently present the best pathway for Qatar, while green hydrogen is expected to become as competitive as blue ammonia in the mid-future. It is widely accepted that as the technologies associated with clean hydrogen production improve, and the cost of renewable energy falls, green hydrogen will become quite competitive in the region. 相似文献
14.
This study proposes a multiperiod mixed integer linear programming model for the management of a single municipal solid waste (MSW) treatment plant with sustainability as the objective. Discrete and continuous variables define the capacity selections for diverse MSW technologies, and the operation of the MSW network, respectively. The economic target is considered to maximize the net present value. The environmental impact is the minimization of a normalized environmental objective function (NEOF). The social target is the maximization of jobs. An interesting feature about the research work is the requirement of biodrying technologies for MSW moisture content control. Due to the conflicted nature among the sustainability components, a multiobjective optimization (MO) is carried out to find the Pareto optimal solutions. The MO results show that the Pareto optimal solutions vary around profit range of $4.9–8.5 billion, NEOF impact range of 3.2–3.6 units, and social benefit range of 2700–4828 jobs. 相似文献
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16.
Elham Sharifikolouei Francesco Baino Camilla Galletti Debora Fino Monica Ferraris 《International Journal of Applied Ceramic Technology》2020,17(1):105-112
Rice husk, an agricultural waste, is abundantly available in many countries such as China, India, Brazil, US, and South East Asia. Despite the massive production of rice husk, it is mainly disposed to landfill. In this work, utilization of rice husk for a potential waste-water treatment is evaluated, along with subsequent encapsulation of the adsorbed heavy metals (Pb and Cd) inside a porous glass-ceramic. Vitrified bottom ash (another source of waste) was mixed with foaming agents in dif- ferent weight ratios (40:60, 50:50, and 60:40) to prepare a glass matrix for encapsulation of Pb-/Cd-loaded rice husk. It was shown that using 40 wt% vitrified bottom ash with 60 wt% foaming agents leads to a foam glass with the best pore size distribution. Therefore, this batch was further mixed with 70 volume% (5 wt%) heavy metal-loaded rice husk and was heat-treated at 750°C for 3 hours. The final glass-ceramic porous structure was char acterized using SEM, XRD, compression test, and it was shown that it is safe to be used as it passes the EN12457-2 leaching test. 相似文献
17.
The emergence of digital platforms based on network algorithms can mediate relationships of trust, boosting sharing economy business models. This study aims to identify the motivations and trust elements of ridesharing apps and analyze the weight of motivation variables in the explanation of trust in the platform service. The survey method was applied to a sample of 485 Brazilian users of a ridesharing app were addressed. Five factors were analyzed to users’ motivation: Perceived sustainability, Security risks, Enjoyment, Platform quality, and Economic reward. Results show that 50.6% of respondents use the service until three times per month (n = 246), while 12,6% use more than four times per week. This study contributes by showing that: (i) five key user motives and two types of trusts are empirically measured and examined for the Brazilian ridesharing market; (ii) the most significant variable that explains trust in platform is “Information providing”, following by platform safety and platform security; (iii) pleasant participation, enjoyment, and cheaper alternative were also significant for the trust in the platform; and (iv) trust in platform is higher than trust in drivers. These contributions could enhance applied solutions for sharing economy platforms and guide academic research on the topic. 相似文献
18.
《International Journal of Hydrogen Energy》2021,46(75):37564-37582
Integrating sector coupling technologies into Hydrogen (H2) based hybrid renewable energy systems (HRES) is becoming a promising way to create energy prosumers, despite the very little research work being done in this largely unexplored field. In this paper, a sector coupling strategy (building and transportation) is developed and applied to a grid-connected PV/battery/H2 HRES, to maximise self-sufficiency for a University campus and to produce power and H2 for driving electric tram in Ouargla, Algeria. A multi-objective size optimization problem is solved as a single objective problem using the ε-constraint method, in which the cost of energy (COE) is defined as the main objective function to be minimized, while both loss of power supply probability (LPSP) and non-renewable usage (NRU) are defined as constraints. Particle swarm optimization and HOMER software are then employed for simulation and optimization purposes. Prior to the two scenarios investigated, a sensitivity study is performed to determine the effects of H2 demand by tram and NRU on the techno-economic feasibility of the proposed system, followed by a new reliability factor introduced in the optimization, namely loss of H2 supply probability (LHSP). The results of the first scenario show that by setting NRUmax = 100%, the system without H2 provides the best solution with COE of 0.016 $/kWh that reaches grid parity and has 13% NRU. However, by setting NRUmax = 1% in the second scenario, an optimized configuration consisting of grid/PV/Electrolyzer/Fuel cell/Storage tank is obtained, which has 0% NRU and COE of 0.1 $/kWh. In the second scenario, it is also observed that an increased number of trams (i.e. increased H2 demands) causes a significant reduction in LHSP, COE, NRU and CO2 emissions. It is thus concluded that the grid/PV combination is the optimal choice for the studied system when considering economic aspects. However, taking into account the growing requirements of future energy systems, grid-connected PV with H2 will be the best solution. 相似文献
19.
江苏沿海滩涂开发优化的动力机制研究 总被引:1,自引:0,他引:1
江苏沿海滩涂开发具有悠久的历史,但是传统的滩涂开发模式已经不能适应江苏省"强富美高"的发展新理念,现有的滩涂开发模式亟需优化升级。经过对由经济发展、生产方式变革、自然环境等要素构成的滩涂优化开发内源动力以及由科技创新、资金保障、政策制度等要素构成的外源动力进行分析,并对其连续动力机制进行深入研究,发现滩涂开发在其内外源动力的共同作用下可以逐步缓解人地矛盾,实现经济效益和富民的效应;但是开发与环境之间互为影响,甚至可能与环境美的目标相反。研究结果表明:在滩涂开发过程中,应坚持生态优先、绿色发展,加强政府引导、理顺机制,注重高新产业、科技投入,围绕临海能源、绿化造林,只有这样才能推动滩涂开发动力机制不断正向循环,实现经济社会的可持续发展。 相似文献
20.
This article examines innovation activities in water infrastructure in Nairobi, Kenya. The focus is on efforts by Nairobi City Water and Sewerage Corporation (NCWSC) to provide water services to the inhabitants in the informal areas of the city using an automated vending machine, or Pre-Paid Dispenser (PPD). In this study, we investigate what happens when a regime actor like NCWSC tries to implement an ambidextrous (two-handed) strategy: managing the existing system according to conventional practice and at the same time innovate in new technical solutions and business models to cater for unconnected users.Besides presenting our results, our aim in this article is also to introduce a research strategy for innovation studies in infrastructural systems in low-income urban areas. Three interconnected parts stand out as our contribution:First, we present a novel conceptual framework, by adding ideas from innovation studies to the Large Technical Systems approach. We investigate how regime actors can innovate to provide water to unconnected users, without expanding the system in a traditional way.Second, we propose a novel method for analysing and understanding innovation on the margins of the infrastructural system, or in our terms, innovation in the critical interface. Central to our method is, through empirical observation, to identify misalignment between the innovation (PPD) and contextual factors at the local level, where the innovation is implemented (interface misalignment), and misalignment between the innovation and the existing water regime (internal misalignment). We use a qualitative method and results forms as a basis for further research and starting point for regime actors in search of an improved ambidextrous strategy.Third, we analyse the innovation process per se. In the Nairobi case, we assess the ambidextrous innovation strategy, and claim that the PPD functions as an adapter in the critical interface, enabling the regime actors to operate in an environment of misalignment. 相似文献