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• We analyse the cost efficiency of the Italian banking system in the 1861–2010 period. • We use stochastic frontier analysis on Italian time series data. • We hypothesise that banking efficiency is driven by solvency and stability. • The results show that the banking efficiency is influenced negatively by banking instability. In this paper, we analyse the performance of the Italian banking system in the 1861–2010 period. In this regard, we apply a stochastic frontier analysis cum ARDL procedure. First, we implement stochastic frontier analysis to the cost function of the Italian banking system in order to identify the years in which the banking system allocated its resources most efficiently. To this end, we propose a version of the stochastic frontier in which the inefficiency term is modelled as a linear function of the capital ratio and of the non-core ratio. The underlying hypothesis is that the efficiency of the banking system is guided by its degree of solvency and stability (capital ratio and non-core ratio, respectively). Finally, in order to verify the existence and stability of a long-term relationship between banking efficiency and capital ratio and non-core-ratio, we implement ARDL estimation. In so doing, we verify whether solvency and stability are two important factors in determining the efficiency of the Italian banking system in the long run. We show that the efficiency of the banking system is influenced negatively by the non-core ratio and positively by the capital ratio, respectively. Finally, only the non-core ratio influences the efficiency of the Italian banking system in the long run. [ABSTRACT FROM AUTHOR]

This paper studies the effects of regulations, input subsidies, their interactions and technical efficiency on cost efficiency and shows how a firm's cost efficiency relates to society's cost efficiency. It finds that from societal viewpoint, the average US public transit system is 45% cost efficient, a product of 84.4% technical efficiency and 53.5% allocative efficiency. From a transit system's viewpoint, it is 78.6%, 59.5% and 84.4% cost efficient when it internalizes input subsidies, regulations and both respectively. Additionally, it finds that the incentive tier regulation reduces capital-labor allocative distortion, the federal labor protection regulation increases nonlabor-labor allocative distortion and cost inefficiency, the incentive regulation increases cost efficiency, and the bus useful-life regulation increases cost inefficiency through increasing technical inefficiency. Together, in the sample of transit systems studied the regulations studied counteract the capital-labor allocative distortion from the subsidies and reinforce the nonlabor-labor allocative distortion from subsidies. • Paper presents a method to decompose cost efficiency based on regulations and subsidy. • It decomposes allocative and technical inefficiencies among their sources. • Transit systems have 51.7% cost efficiency, 88.4% technical efficiency and 58.5% allocative efficiency. • Those that internalize input subsidy compared to input regulations are more efficient. [ABSTRACT FROM AUTHOR]

Exposure factors form the basis of reliable exposure estimates. The growing demand for population-specific exposure factors for complex exposure models is challenged by continuously declining response rates in surveys: Current survey methods clearly need a boost by user-friendly and efficient technologies. We compared the performance of a smartphone app to a paper questionnaire based on a survey on exposure factors that offered the choice between both methods and based on an observational study that investigated the performance of both methods. The development costs for smartphone app and paper questionnaire were comparable with 15′000 and 13′500 US-$, respectively. The cost efficiency for the paper questionnaire was much better than for the app, but model calculations show that the cost efficiency of the app improves considerably with adequate promotion and for larger surveys, especially for those with regular repetitions. Barcode scanning of consumer products by app saved time and effort of the participants and enhanced reliability. The app was able to attract the attention of younger adults between 20 and 40 years old: Thus, the limited representativity for younger age groups that sometimes is observed for paper-based surveys may be enhanced by including the option to use an app in a mixed-mode survey. [ABSTRACT FROM AUTHOR]

• A unique, new dataset of road maintenance contracts in Sweden is used (2004–2014; 623 observations). • A rich model controls for heterogeneity (including weather) prior to the estimation of efficiency. • Private contractors are found to be substantially cheaper than the state-run company. • Thus competitive tendering has worked but is not yet functioning optimally. • Possible explanations for the public/private gap are put forward. This paper uses econometric methods to study the cost efficiency of road maintenance provision in Sweden for the first time. The novelty lies in the application of econometric techniques to a new and rich panel dataset (73 contracts; 11 years, 2004–2014) with a wide range of variables and approaches to controlling for heterogeneity (including weather variation). The analysis is applied in the context of a sector where all road maintenance contracts are subject to competitive tendering, but with a state-run provider competing against private firms. The key focus is whether, even after competitive tendering, efficiency differences remain between the state provider and private entrants. We find that the state-run provider has significantly higher costs (between 8 and 20%) than private firms despite holding 60% of the market. The results suggest that substantial savings are possible through opening up road maintenance to the private sector through competition for the market; but that in Sweden, the tendering process is still not working optimally. Further research is needed to understand why the current cost gap persists between public and private providers, despite competitive tendering having been present across the whole market for several years. [ABSTRACT FROM AUTHOR]

Industry 4.0 is revolutionizing decision making processes within the manufacturing industry. Among the technological portfolio enabling this revolution, the late literature has capitalized on the potential of data analytics for improving the production cycle at different stages, from resource provisioning to planning, delivery and storage. However, such a promising role of data analytics has been so far explored without a proper, quantitative inspection of the cost-improvement trade-off, nor has the process of acquiring sensors and extracting valuable information from their captured data formalized in a series of methodological steps. This paper introduces the Analyze, Sense, Preprocess, Predict, Implement and Deploy (ASPPID) methodology, an iterative decision workflow that spans from the acquisition of sensing equipment to the quantitative assessment of the contribution of their captured data to enhance the production step under focus. By placing the data scientist at the core of the workflow, this methodology helps improvement teams make informed decisions about which parts of the process need to be sensed, and how to exploit this information towards a verifiable improvement of the production cycle. The implementation of this methodology is exemplified in a real use case within the automotive industry, where the detection of defects in an annealing process can be modeled as a classification problem over a highly imbalanced dataset. Results obtained after applying the proposed ASPPID methodology show that the scrap ratio is reduced by sensing the correct part of the process at minimal investment costs, thus highlighting the crucial role of the data scientist in the management team of manufacturing plants. • ASPPID: an iterative data-based decision workflow for cost-efficiently sensing smart industries. • A comprehensive description of how data analytics should play a central role within the proposed methodology. • A real case study of the application of ASPPID to defect detection in a manufacturing industry. [ABSTRACT FROM AUTHOR]

Abstract Environment life cycle cost (E-LCC) is rapidly becoming an important strategy for firms that deal with environmental issues. In this paper, the researchers use evolutionary game model to investigate how E-LCC control affects manufacturers' decision-making behavior. Under different LCC control choices, three competition market structures are formulated. Individual benefits are also calculated. Using an equilibrium solution, the researchers analyzed the effects of consumer environmental awareness (CEA), market capacity, and conventional-LCC (C-LCC) efficiency on equilibrium decisions. Results suggest that CEA can promote E-LCC strategy. However, it is negatively associated with C-LCC efficient level and market capacity. These findings help firms and governments choose strategies and environmental policies, respectively. [ABSTRACT FROM AUTHOR]

Clean water is crucial for sustainable economic and social development; however, around the world low water use efficiency and increasing water pollution have become serious problems. To comprehensively evaluate water use and wastewater treatment, this paper integrated bi-level programming (BLP) and Data Envelopment Analysis (DEA) with a feedback variable to deal with poor output to rank DMUs using a super efficiency DEA. The proposed model was applied to a case study of 10 cities in the Minjiang River Basin to demonstrate the applicability and effectiveness, from which it was found that a water system can only be cost-efficient when both the water use and wastewater treatment subsystems are both cost-efficient. The comparison analysis demonstrated that the proposed model was more discriminating, and stable than traditional DEA models and was able to better improve total water system cost efficiencies than a BLP-DEA model. [ABSTRACT FROM AUTHOR]

State Transport Undertakings (STUs) are key players in providing mass road transport in India. Given that they operate under high levels of government imposed regulatory constraints, it is imperative to study their efficiency levels. Given that capital is a relatively scarce resource in developing countries like India, it is important to obtain efficiency in the short-run where some inputs are fixed as well as over the long run, where all inputs are variable. The technique used for capturing efficiency is Data Envelopment Analysis (DEA). A key possible limitation of DEA models based on physical inputs and outputs is that for an inefficient firm, reduction in some or all inputs may be recommended. It may often be desirable for an inefficient firm to increase some less expensive inputs while reducing the use of relatively expensive ones. Hence, when market price data is available, it is advisable to use the cost variant of DEA. Also, it is possible to determine variable cost efficiency in the short run when some inputs cannot be varied. Such inputs are referred to as “quasi-fixed” inputs. In this paper, we examine short and long term efficiencies of select bus companies in India known as State Transport Undertakings (STUs) over a period of 10 years. Fleet strength has been used as the quasi-fixed input. It is possible to ascertain, through a comparison of shadow price of the quasi-fixed input, vis-à-vis its market price, as to whether the quantity of this input is sub-optimally small or large. It is found that by adopting efficiency enhancing practices, STUs can cumulatively reduce their operating costs to the extent of 9123.35 million dollars. Also the tendency to minimize costs is found to be declining over time. In the short run some STUs are found to operate with a sub optimally low fleet size. [ABSTRACT FROM AUTHOR]

Given the growing pressure on aeronautical revenues, the increasing focus on airports’ financial performance and the sharpened state aid guidelines in Europe, it is valuable to have detailed insight in the determinants for airport profitability. This paper fills in a gap in scientific research by presenting the most important traffic and financial determinants for airport profitability, since the majority of scientific literature on airport (financial) performance focuses on efficiency rather than on profitability. Comprehensive airport traffic and financial data for 125 airports in Europe, the United States (US), Canada, Australia and New Zealand for the period 2010–2016 have been used to estimate several fixed-effects panel data regression on profit margin. Among others, the results show evidence for the fact that an increasing share of transfer passengers affects an airport’s profit margin. In addition, there is no sign of a general LCC effect and just limited evidence for the fact that the market share of specific LCCs affect airport profitability: only an increase in the market share of Southwest Airlines at major airports leads to lower profit margins. Moreover, a quadratic relationship between seasonality and profitability has been identified. It points at the existence of a certain optimal seasonality score. Below that tipping point, a decrease in seasonality leads to higher profit margins. On the contrary, a further reduction of seasonality after the tipping point leads to lower profit margins. This might indicate that no or limited seasonality is a result of capacity constraints and, in turn, leads to increasing operating costs related to congestion. Regarding financial variables, the results especially show significant positive effects of capital cost efficiencies on profitability. Those effects are especially large for airports in the US and for small regional airports. Labour productivity only plays a important role in the profitability of US airports. Finally, the results show that regional O/D airports largely depend on regional economic development and population growth, while the major airports rather depend on global economic development than on an increase in local demand. [ABSTRACT FROM AUTHOR]

Policy schemes that aim to stimulate the cultivation of biofuel crops typically ignore the spatial heterogeneity in costs and benefits associated with their production. Because of spatial heterogeneity in biophysical, and current agricultural production factors, potential gains from stimulating biofuel crops are non-uniformly distributed across space. This paper explores implications of this type of heterogeneity for the net benefits associated with different subsidy schemes. We present a simple framework based on discounted cash flows, to assess potential gains from introducing the notion of heterogeneity into stimulation schemes. We show that agricultural subsidy spending can be reduced in a Pareto efficient way and simultaneously improve the total stimulation potential of biofuel policies, when schemes: 1) are production based instead of land based; 2) accommodate differences in opportunity costs, and 3) target sites where subsidies for conventional agricultural land-use types are high. These results are robust for a range of different bioenergy prices and the relative gains of addressing these key elements in policy compared to conventional stimulation schemes increase with lower bioenergy prices, and are largest when low prices coincide with high emission reduction ambitions. [ABSTRACT FROM AUTHOR]

As we enter the deep submicron era, the number of transistors integrated on die is exponentially increased. While the additional transistors largely boost the processor performance, a repugnant side effect caused by the evolution is the ever-rising power consumption and chip temperature. It is widely acknowledged that the shortage of power supplied to a processor will be a major hazard to sustain the generational performance scaling, if the processor design is to follow the conventional approach. To utilize the on-chip resources in an efficient manner, computer architects need to consider new design paradigms that effectively leverage the advantages of modern semiconductor technology. In this paper, we address this issue by exploiting the device-heterogeneity and two-fold asymmetry in the processor manufacturing. We conduct a thorough investigation on these design patterns from different evaluation perspectives including performance, energy-efficiency, and cost-efficiency. Our observations can provide insightful guidance to the design of future processors. [ABSTRACT FROM AUTHOR]

Copper mining and processing activities at an abandoned mine in the Lefke-Xeros area of Cyprus have created a huge environmental contamination problem in the locality. As an alternative mitigation and management measure, we reported in previous studies that these tailings could be used as a concrete making material. In this paper, results of an experimental investigation of the reinforcement corrosion performance and cost efficiency of 0.57 and 0.50 w/b ratio concrete containing copper tailings either as a cement replacement or an additive material are presented. The time to initiation of corrosion and half-cell potential (HCP) of reinforcements were measured. Actual corrosion status of extracted reinforcement bars was also verified by visual inspection. Results showed that while early corrosion initiation occurred in some samples containing tailings as a cement replacement material, delayed corrosion initiation was observed in all samples containing copper tailings as an additive. Although HCP values became slightly more electronegative as tailings content of samples increased, no substantial reinforcement corrosion was observed. Based on corrosion performance and cost efficiency analyses, utilization of 5% pre-wetted tailings either as a cement replacement or an additive material is the best tailings reuse approach. Increased tourism-related businesses associated with reduced pollution of the Lefke-Xeros coastal area would have a positive impact on the socioeconomic status of the community. [ABSTRACT FROM AUTHOR]

This paper presents the results of an empirical study aimed at evaluating the cost efficiency of 108 Italian major municipalities, and investigating to what extent the municipality efficiency is also associated to the effectiveness of public expenditure, and consequently to quality of services offered to citizens. The study implements Data Envelopment Analysis to calculate the efficiency score and understand if it is influenced by scale economies and determine the type of these economies. For this purpose, every municipality was modeled as a production function using 6 cost item inputs and 2 outputs. Finally, the study implemented a truncated regression equation using the bootstrapped efficiency estimate as the dependent variable, and a selection of indicators measuring the quality of public services offered in the context as the independent variables. Results reveal that there exist important scale inefficiencies in a number of municipalities, but unexpectedly a great amount of inefficiencies are caused by decreasing returns to scale. Additionally, the study suggests that a trade-off between expenditure efficiency and effectiveness, i.e. the quality of public service, seems to exist. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to present the problems of French public transit, facing a funding crisis. The prominent features of the French transit are presented. First, we describe the complex and opaque bidding process which is for the entire network. Then we evoke a payroll tax especially devoted to the transit and underline the fact that the system is heavily subsidised. As competing for the entire network might find its rationale in the scale and scope economies, we test some very simple models devoted to this issue. We found no evidence of economies of scale for bus networks. This, given the funding crisis of transit authorities, leads us to recommend a gradual reform of French transit competitive tendering process. This reform should lead to a slowdown in the upward trend of transit employee's salaries. Some smaller parts of the networks would be submitted to bidding processes. The contracts might be improved as well. [ABSTRACT FROM AUTHOR]

In this paper we estimated the potential of Phragmites australis as an energy source in the Vojvodina region, northern Serbia. Reed is chosen for this study due to its availability, high growth rates, carbon neutrality, characteristics that are beneficial for the sustainability of the ecosystem, and the fact that it does not violate and compete with the surfaces used for food production. Biomass of P. australis can be converted into energy by combustion, producing cellulosic ethanol and biogas. The Province of Vojvodina is a typical lowland region chracterized by intensive agriculture and reduced area with natural vegetation. It comprises cc. 27% of the country’s total population. It is an energy-deficient province. The theoretical potential of reed, as a material for the generation of electric energy could meet one quarter of electricity needs in Vojvodina. It can also contribute to the heat energy production with 6390 TJ. As a whole, the Province of Vojvodina has a great potential to produce the reed biomass. However, bioenergy production is not feasible yet, due to the high cost of biomass processing. The significance of reed was more local in character until now, taking into account its ability to purify various types of ecosystems. The use of common reed in systems for ecoremediation (e.g. constructed wetlands in Slovenia) proved to be very efficient and cost-effective. Hence, reed can be considered a potentially profitable energy source in Vojvodina, when the values that are more difficult to estimate are taken into account. [ABSTRACT FROM AUTHOR]

• Degree of dewatering as a consequence of the substrate/mortar interaction is studied. • Dewatering mortars by means of copper tailings were reported for the first time. • Dewatering has shown to critically affect the properties of the resultant mortars. • Improved physical and mechanical properties of dewatered mortars are attained. • Use of copper tailings in mortars supports environmental and social sustainability. The unexpected closure of the mine processing area of Lefke-Xeros generated the largest environmental disaster in the recent history of Northern Cyprus. The mining area, formed the biggest industry on the island in 1950s, was unpredictably closed and left all mine tailings and equipment behind without any preservation towards the environmental remediation nor sustainable rehabilitation for the locality. Substantial increase in the cost of energy supply, determination to decrease CO 2 emissions and to reduce the consumption of natural materials on the other hand, are the major challenges in construction practice. The paper is investigating the consequences of dewatering by means of recycling copper mine tailings in mortars both for the sustainable development of construction materials and for the socio-economic recovery of Lefke-Xeros area of Cyprus. The degree of dewatering as a consequence of the substrate/mortar interaction on the mechanical and physical properties of cement and lime mortars containing copper tailings are reported in the paper. Physical measurements provided an insight into the actual effect of dewatering on the resistance of freezing and thawing action of mortars containing copper tailings. The use of copper tailings and therefore the degree of dewatering have shown to play a substantial role in the decrease in thermal conductivity and increase in cost efficiency of these mortars in construction practice. The results reported in this paper significantly contribute in the sustainable development of construction materials through the use of mine tailings to support environmental sustainability and socio-economic development of Lefke-Xeros area of Cyprus. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this paper is to identify benchmark cost-efficient General Practitioner (GP) units at delivering health care in the Geriatric and General Medicine (GMG) specialty and estimate potential cost savings. The use of a single medical specialty makes it possible to reflect more accurately the medical condition of the List population of the Practice so as to contextualize its expenditure on care for patients. We use Data Envelopment Analysis (DEA) to estimate the potential for cost savings at GP units and to decompose these savings into those attributable to the reduction of resource use, to altering the mix of resources used and to those attributable to securing better resource ‘prices’. The results reveal a considerable potential for savings of varying composition across GP units. [Copyright &y& Elsevier]

Abstract: The heavy losses of China’s thermal power industry have attracted lots of attention. Besides the adjustment of power price, how to improve its poor performance becomes an important issue. Combining the cost Malmquist with the Luenberger index, this paper introduces a new method to measure the cost efficiencies of China’s 30 provinces’ thermal power industries with carbon emissions considered. Furthermore, we quantify the influence of input price changes on the price effect (PE) using panel data regression. The empirical results indicate that: (1) combining dynamic efficiency with static efficiency, the results will be more objective; (2) compared with previous emphasis on adjusting external factors, the future policy reforms should incentivize corporations to improve their management; and (3) external fuel price change is not the direct reason for cost efficiency fluctuation, and the thermal power industry should make more efforts to improve their technical efficiency. [Copyright &y& Elsevier]

Unexpected closure of the operations at an abandoned mine in the Lefke-Xeros area of Cyprus has resulted in an enormous environmental degradation and health hazards in the locality. In order to explore the possible ways for the rehabilitation of the abandoned mine site as well as to suggest alternative waste management approaches, gold mine tailings of Lefke-Xeros area are incorporated in cement mortars in this paper. Experimental measures such as compressive strength, water penetration depth, porosity, resistance to freeze/thaw cycling and carbonation depth of cement mortars incorporating gold tailings, carried out over the period of 9 months, have shown to be improved significantly. The release of heavy metals of cement mixtures incorporating gold tailings were substantially lower than the limits of US Code of Regulations. Cost effectiveness analysis also validated the efficient use of gold tailings both as cement and sand replacement in these mortars. Particularly, it is shown in the paper that the use of 30% gold tailings as a binder replacement resulted in a 22% decrease in the CO 2 emissions arises from cement manufacturing. It must be emphasized that the use of gold tailings does not only result in a considerable reduction in CO 2 emissions originates from cement production but also plays a crucial role in sustaining a healthy ecosystem of the immediate environment after the closure of mine sites and helps maintaining the economic growth of the locality. [ABSTRACT FROM AUTHOR]

Abstract: Providing operators with objective incentives for cost efficiency and continuous improvement in the provision of public services are major concerns for regulators. Measuring efficiency empirically is complex and this complexity is accentuated when the same operator is responsible for delivering more than one service (e.g. in order to explore potential economies of scope). Based on a sample of operators that provide water and wastewater services, this paper uses a shared input data envelopment analysis model to measure separately the efficiency of each service. The results show that a single measure may not provide enough information for monitoring multi-utilities. Together with other indicators, the proposed model can assist decision-makers in prioritizing efforts to improve overall efficiency. [Copyright &y& Elsevier]

Abstract: The recent economic downturn took a severe toll on the aviation industry, leading to a significant contraction in air transport demand. In spite of that, airports'' operating costs did not mirror the declining traffic trends and continued to increase during the same period. This paper sought to estimate the impact of the recession on airports'' cost efficiency and financial performance. This is achieved by estimating the industry''s short-run cost frontier over a balanced pool database of 194 airports observed between 2007 and 2009. Results show that airports struggled to control operating costs during the recession. Efficiency losses were estimated to be in excess of USD 5.5 billion, contributing to a significant reduction in industry operating margin. Results also suggest that airports that are corporatised and have not pursued extensive out-sourcing of activities are better able to manage their costs during periods of economic recession. [Copyright &y& Elsevier]

Abstract: This paper proposed an adjusted “shared-input” version of the popular efficiency measurement technique Data Envelopment Analysis (DEA) that enables evaluating municipality waste collection and processing performances in settings in which one input (waste costs) is shared among treatment efforts of multiple municipal solid waste fractions. The main advantage of this version of DEA is that it not only provides an estimate of the municipalities overall cost efficiency but also estimates of the municipalities’ cost efficiency in the treatment of the different fractions of municipal solid waste (MSW). To illustrate the practical usefulness of the shared input DEA-model, we apply the model to data on 293 municipalities in Flanders, Belgium, for the year 2008. [Copyright &y& Elsevier]

Abstract: In this paper a simple way of computing technical, scale, cost and allocative efficiency scores for homogeneous networks of processes is presented. The system Production Possibility Set (PPS) is formed through the composition of the PPS of the individual processes, which, in turn, are modelled in the conventional, axiomatic way using observed data. Firstly, the overall system scale and technical efficiency are computed using the relational network DEA approach. Local Returns To Scale (RTS) can also be estimated with these models. Secondly, assuming the prices of exogenous inputs are known, a minimum cost network DEA model is solved, from which cost and allocative efficiencies are derived. The proposed approach is illustrated with a two-stage problem from the literature, showing the usefulness of a more detailed problem assessment both in terms of technical and scale efficiency and RTS and in terms of cost and allocative efficiency. [Copyright &y& Elsevier]

Abstract: Contracted service comprises a significant proportion of total operating expenses in the provision of fixed-route bus transit service in the US. Despite its importance, the literature on the economic effects of transit service contracting has been limited to only a few studies since the mid-1990s, and is inconclusive due to problems with the nature and methodology of the past studies. This paper examines how the cost efficiency of providing fixed-route bus transit service varies by the degree of contracting. I make several improvements to previous studies and conduct a regression analysis that: (1) addresses the endogeneity problem between the contracting decision and cost efficiency, (2) differentiates between agencies that contract out only a portion of service from those that contract out all service, (3) takes into account the moderating effects of several factors on the effect of contracting on cost efficiency, and (4) uses a relatively larger set of cross-sectional time-series data constructed from the National Transit Database from 1992 to 2000. The analysis results show that the combined effects of contracting lower operating costs by $4.09 and $2.89 per vehicle hour for partial and full-contracting agencies, respectively, in the average case. These average cost savings translate into 7.8% and 5.5%, using the average operating cost per vehicle hour of $53.06. However, this improvement is not universal, because the effects of contracting on cost efficiency vary by factors such as peak-to-base ratio, agency size, the wage gap between bus operators in the public and private sectors, and agency type. [Copyright &y& Elsevier]

Abstract: The industrial sector is the biggest electricity consumer in Malaysia. Electric motors account for more than 45% of the electricity consumption in the industrial sector in the country. Therefore, it is very important to implement energy efficiency standards for electric motors to reduce energy consumption growth in this sector. This paper attempts to calculate the cost efficiency analysis and emission reduction by implementing energy efficiency standards for electric motor in Malaysia. The energy efficiency standards are proposed based on the efficiency of electric motors from survey data. The study examines the potential energy, economical and environmental impacts of the implementation of energy efficiency standards for electric motors in three scenarios i.e. 0.5%, 1.0% and 1.5% of standards efficiency improvement. Standards also enable consumers to reduce their electricity bill and contribute to a positive environmental impact. [Copyright &y& Elsevier]

Abstract: Dynamic DEA (DDEA) is a mathematical programming-based technique which assesses the performance of decision making units (DMUs) in the presence of time factor. This paper provides a new technique for reducing the computational complexity of some recently introduced DDEA models. [Copyright &y& Elsevier]

Abstract: This paper presents a new formula for decomposing cost efficiency into technical, price, and allocative efficiencies in an environment marked by the fact that unit input prices differ among certain enterprises. We employed this formula in comparing cost efficiency between Japanese and US electric power companies, and found a significant difference in the price-based efficiency. However, negligible differences were found in the technical and allocative efficiencies. [Copyright &y& Elsevier]

Abstract: The purpose of this paper is to improve the cost efficiency interval of a decision making unit by adjusting its observed inputs and outputs. We first propose a DEA-based model with an interval efficiency in which the lower bound and upper bound of this interval, are respectively, the efficiency obtained from optimistic and pessimistic viewpoints. Then, units which are not prevail as cost efficient, are improved so that their lower bounds of cost efficiency become as large as possible and their upper bound attain the maximum value 1. The particular application area investigated is that involving the gas companies of Iran. [Copyright &y& Elsevier]

Abstract: Glass façades, particularly in high-rise buildings, increase in energy consumption for heating, cooling and ventilation. This causes too high running cost of mechanical systems. Double skin glass façade is a system that decreases these disadvantages, by providing natural ventilation, preventing solar heat gain, controlling daylight, etc. This paper aims to investigate the appropriateness of double skin glass façades in moderate climate, such as Istanbul, in terms of the energy and cost efficiency when compared to single skin glass façades. For this purpose, an approach is proposed to determine the efficient alternatives. It comprises to generate standard façade alternatives by considering the objectives, constraints and performance criteria, and to evaluate their energy and cost efficiency for both single and double skin glass façades. In conclusion, the most energy efficient double skin glass façade is about 22.84% more efficient than the most energy efficient single skin glass façade is. Additionally, the most cost efficient single skin glass façade is about 24.68% more efficient than the most cost efficient double skin glass façade is. [Copyright &y& Elsevier]

• State-of-the-Art of 3DP technology in textile clothing industries. • Materials and process descriptions relevant to manufacturing 3D printed polymer-fiber composites in textile and fashion. • In depth discussion on SLS, SLA, FDM, inkjet, binder and micro-extrusion printing process. • Future prospects of 3DP in regard to sustainability, novelty, complexity in fashion related fields. • Personalized style and design-oriented textile apparel and accessories. Three-dimensional printing (3DP) technology has gained an increased popularity in making prototypes in all types of manufacturing industries including automotive, healthcare, aerospace, sports, textile, apparel and fashion industry etc. Researchers, textile technologists, fashion designers, manufacturers and retailers have been working on adopting 3DP technology in their respective fields since the last decade. 3DP has been proved highly beneficial in reducing manufacturing time and production cost significantly regarding fiber reinforced composites fabrication. However, the application of this technology is still at niche while it comes to manufacturing everyday clothing. The purpose of this paper is to provide an integrative review of the existing literature to identify current state-of-the-art 3DP methods, materials, application in the textile and fashion industries. Further, the review considers the future of this technology with regard to sustainability, novelty, complexity in fashion related fields. [ABSTRACT FROM AUTHOR]

•The proposed residential load scheduling strategy in smart grid is capable to achieve the optimal energy consumption profile. •The cost efficiency based on consumer's preference is modeled to measure the effectiveness of consumption expenditure. •The study of cost efficiency in different household consumption patterns contribute to guide the consumer to enjoy convenience while saving costs. •Various simulation experiments are performed to confirm that there is a positive correlation between cost efficiency and consumer's preference. With the wide application of consumer's electric appliances with flexible power supply or start time and competitive energy markets, it is necessary for the residential consumers to optimize the power scheduling strategy. The existing methods require consumer's awareness, flexibility, and timely responsiveness which remain an obstacle due to the impacts on the lifestyle and preference of consumers. To overcome the obstacle, this paper proposed a residential load scheduling algorithm based on cost efficiency (CE) and consumer's preference (CP) for demand response in smart grid. In this proposed method, the CP is modeled based on the load scheduling framework, the CE based on CP is modeled to measure the effectiveness of consumption expenditure and the relationship between the CE and CP is investigated. Meanwhile, by analyzing the consumer's lifestyle, we develop a load scheduling algorithm based on CE and CP to effectively reflect and affect user's consumption behavior and achieve the optimal energy consumption profile. The method is demonstrated using real data sets. The simulation results show that there is a positive correlation between CE and CP. The proposed method realizes a desired trade-off between the economic efficiency and CP, helping the consumers to enjoy convenience while saving costs. [ABSTRACT FROM AUTHOR]

Distributed data stores are critical to the success of applications in cloud. Massive volumes of user data are stored and processed with the support of underlying distributed data stores. With large amounts of data stored remotely in the cloud, security becomes a major concern. Authentication and access control are provided by cloud storage providers. But even with proper authentication and access control policies, storage systems are still vulnerable to attackers who have direct access to storage devices such as disks. Encryption makes it computational difficult to retrieve the original data even when the attackers have the access to the disks. However, there are many challenges in designing an encrypted distributed data store that is highly secure and cost-aware. In this paper, we show that security flexibility and cost efficiency can be achieved at the same time. We present Carp, a cost- aware relaxed protocol for encrypted data stores. Carp is a heuristic solution instead of an optimal one. The key idea is to reduce additional encryption operations for frequently accessed data. It is achieved by allowing data objects stay unencrypted for a short time period after the data are accessed. Reducing encryption operations eventually means reducing the computational cost and power consumption in the data store. Unlike conventional encrypted file systems which store data encryption keys on disks, we present a hybrid design of key generation and caching. Data encryption keys are generated for individual objects or a group of them using cryptographic hashing. We develop a prototype data store and conduct experiments. The experimental results show that Carp can reduce up to 20% encryption operations with high-level security. [ABSTRACT FROM AUTHOR]

Abstract: In this paper some effective techniques for reducing the computational complexity of cost efficiency analysis models are provided. [Copyright &y& Elsevier]

• Comprehensive analysis of country-specific boundary conditions and success factors. • National heat supply systems and incentive policies are essential. • Role of district heating utilities in Denmark for solar district heating success. • Technological solutions and best practice examples of large-scale systems. • First-hand market research on China shows higher market penetration than assumed. Large-scale solar thermal systems are a cost-efficient technology to provide renewable heat. The rapid market growth in the last decade has been concentrated on a small number of countries, with the outstanding position of Denmark followed by China, Germany and Austria. This paper provides a comprehensive overview of the market and common technological solutions for large-scale solar thermal systems in these countries. Country-specific factors, including solar resources, heat supply systems, competing technologies, promotion schemes and business models, which put these countries in a leading role, are analyzed in detail using an integrated assessment framework. For each country, a best practice solar heating system is introduced. The analysis shows that heat supply by large-scale solar thermal systems is a mature technology with a broad field of applications and that mainly country-specific boundary conditions regarding the heat supply system and incentive policy are responsible for the preeminent role of these four countries. The unique role of district heating utilities in Denmark, which are subject to a national emissions trading system and often act both as investors and operators of large-scale solar thermal systems, can serve as a role model for other countries. [ABSTRACT FROM AUTHOR]

Marine aquaculture has increased in importance in most countries over recent decades. In order to develop this sector in a sustainable way, it is necessary to consider its environmental impacts. In Vietnam, marine cage lobster cultivation has been seen as a high return business. However, in recent years, the sector has been facing sustainability issues, with recurrent disease outbreaks and increased lobster mortality. These phenomena are linked to nutrient pollution, which is attributed to the overuse of feed inputs. The annual loss for the sector is reported to be up to 30 million USD. Local lobster farmers have reacted to these issues by spending more on antibiotics and chemicals, or by increasing efforts to clean cages. This behavior suggests that farmers perceive a conflict between reducing environmental pressure and improving the economic performance of the sector. In order to identify the relationship between cost and environmental efficiency, this paper uses a Material Balance Principle based Data Envelopment Analysis approach using a dataset of 353 marine cage lobster farms in Vietnam. The findings show that improvements in input use efficiency would result in both lower production costs and better environmental performance. If lobster farms were to become more cost efficient, using a more appropriate input mix, given the input price information, this would benefit the environment. Similarly, improving environmental performance generally also reduces production costs. • Marine aquaculture in Vietnam is cost inefficient and environmentally inefficient. • There is a win-win relationship when improving environmental or cost efficiency. • Improving technical efficiency has positive cost and environmental effects. [ABSTRACT FROM AUTHOR]