Related Operating Costs Research Articles

Gender-based Factors Influencing the Choice of Communication Media for Accessing Agricultural Information in Kilosa and Mvomero Districts, Tanzania

The study examined socio-economic factors influencing the choice of communication media for accessing agricultural information among gender categories, that is, men, women, and youths in Kilosa and Mvomero districts of Tanzania. Data were collected from a sample of 240 selected farmers. Information was collected using structured and semi-structured interviews, and document reviews. The collected data were analyzed through descriptive, inferential and qualitative approaches. A multinomial logit was estimated to identify socio-economic factors such as age of a farmer in farming, education level, types of assets owned, farmer’s marital status, income and nature of farming enterprise in influencing the choice of communication media for accessing agricultural information among men, women, and youths. Results showed that the choice of either television or video or mobile phones or Internet or leaflets or booklets over radio was not statistically gender based. In addition, the choice of leaflets and television by famers over radio in rural areas was influenced by their education level and income at 1% and 3% level of significance respectively. The increase of 1.5 years in schooling influences the farmer to choose leaflets than radio. Similarly, increase of income by 0.3% influences him/her to choose television rather than radio. The income enables the farmer to increase his/her television purchasing power and meet related operational costs by 2%. Generally, the study concludes that the choice between television, video, mobile phones, Internet, leaflets, or booklets over radio was not influenced by gender. However, farmers with low education and income levels did not choose leaflets and television, respectively. The study recommends that policy-makers should formulate appropriate strategies for motivating farmers with low level of education to read leaflets and mobilizing financial resource to enable the government’s intervention on subsidizing television to boost its usage by low-income farmers for timely access to agricultural information.

A novel hybrid assembly method to reduce operational costs of selective assembly

Selective assembly is a technique whereby components are smartly matched depending on their measured feature values. Although it can reduce scrap by allowing more relaxed tolerances on components when compared to traditional random assembly, it is often not adopted due to the high related operational costs. Therefore, this study proposes a novel hybrid strategy whereby a number of traditional assembly rounds are performed before switching to selective assembly. At each round, the components which did not lead to a feasible assembly are put into their respective unmatched piles and are used for the next traditional assembly round. When N such rounds have been performed, the remaining unmatched components will finally be assembled via selective assembly.To determine the optimal number of traditional assembly rounds before moving on to selective assembly, a cost function depending on the matching probabilities at each round and the relative costs of selective and traditional assembly is developed together with an optimality condition. Since the analytic calculation of the matching probabilities is in most of the practical cases infeasible, these are estimated using simulation. Particular attention is paid to reducing the variance of the estimators for the matching probabilities, and to their impact on the total variability of the cost function. The application of this innovative method to two case studies demonstrates that the proposed hybrid technique can significantly reduce operational costs of selective assembly, while still taking advantage of its typical benefits.

A multi-trip vehicle routing problem considering time windows and limited duration under a heterogeneous fleet and parking constraints in cold supply chain logistics

ABSTRACT Cold supply chain distribution systems ensure the freshness of temperature-sensitive products during transportation. In this study, we investigated a fresh food company’s cold supply chain distribution. Making fresh food available and achieving quality and safety, requires proper planning of vehicle routing, we addressed a routing problem that simultaneously considers time windows, multiple trips per vehicle, a heterogeneous fleet, parking constraints, unloading time at customer position, and limited duration, minimizing related operational costs. We formulate this problem as a mixed-integer programming model. Since this problem is NP-hard, we also propose a genetic algorithm with two adaptive-parameter mechanisms to solve it within a reasonable computational time. Extensive experiments were conducted to assess the performance of different approaches in a real-world application. The results demonstrate that the algorithms are robust and efficient. The proposed algorithms can reduce operational costs by more than 20% compared to the current practical planning approach.

Performance of solar-air source heat pump heating system aided by district heat supply network research

Abstract To improve the usage rate of district heat supply network and solve the frost problem in solar-air heat pumps, this study used TRNSYS to construct a new solar-air source heat pump heating composite system that uses waste heat from the district heat supply network. The impact of the waste heat recovery device on the heating performance of the new composite system was analysed, and the economic and environmental performance of the composite system was compared with other heating systems. During a typical day, the average coefficient of performance of air source heat pumps (COP) of the composite system increased by 13% and the power consumption of the system decreased by 35.9%. Throughout the heating season, the power consumption of the composite system was 13.59% higher than that of traditional systems, and system coefficient of performance (SCOP) was 15.89% lower than traditional systems. Based on economic analysis, the relative operating costs of the composite system, coal-fired boiler, gas-fired boiler, oil-fired boiler and combined heat and power (CHP) are 1, 1.19, 2.33, 5.56 and 0.85, respectively. The operating cost of the composite heat source system is only 17.43% higher than that of CHP and lower than the other three heating systems. Quantitative evaluations of the environmental friendliness of these systems were conducted using the fuzzy analysis mathematical method. The evaluation results were 9.62, 5.89, 15.05, 9.10 and 6.79, respectively. It was found that the composite system is second only to the gas-fired boiler in terms of environmental friendliness and is 38.9% higher than the coal-fired boiler and 29.5% higher than the CHP.

Study on migration of gold particles in technogenic sands of placer deposits

Technogenic placers are characterized by a chaotic distribution of gold and other valuable components, which restricts their industrial mining for gold. The development of an effective mining method for technogenic placers is therefore of great national economic importance. The study is aimed at creating a new type of technogenic placer deposits with high gold grade zones, to be formed through the preferred vertical migration of high-density particles under the influence of natural and industrial factors. The resulting enriched zone shall have higher gold grades as compared to the original technogenic mass, with a thickness equal to 45–60 % of the thickness of the technogenic placer. This will reduce the volume of sand to be washed and significantly cut the related operating costs. This technology will allow mining technogenic placer deposits that have been previously considered unprofitable. The study is aimed at finding the optimal parameters of rock mass cyclic flooding and drainage that would ensure the most intensive migration of gold particles, as well as at assessing the effect of rock mass grain-size distribution on the intensity of gold migration. The data obtained facilitate a significant expansion in the theoretical knowledge on gold particle migration and identification of migration intensity patterns for various gold particle sizes, depending on the seepage flow parameters and mining and geological characteristics of the rock mass in respective technogenic placers.The work was carried out with the financial support of Government of the Khabarovsk Territory under the program «On the provisionof grants in the form of subsidie s from the regional budget for the implementation of projects in the field of scientific research in the direction of natural, technical, humanitarian and social sciences».The research was carried out using the resources of the Center for Collective Use of Scientific Equipment «Center for Processing and Storing Scientific Data of the Far Eastern Branch of the Russian Academy of Sciences», funded by the Ministry of Science and Higher Education of the Russian Federation under project No. 075-15-2021-663.Experimental studies, sample preparation, determination of gold content were carried out on the basis of the Center for Collective Use «Center for Research of Mineral Raw Materials» of the Khabarovsk Federal Research Center of the Far Eastern Branch of RAS.

Future Development of Renewable Energy in Russia: A Case of Solar Power

Currently, there is a growing number of studies related to assessing the cost-effectiveness of renewable energy projects around the world. This topic is also very relevant for the Russian energy market that is otherwise dominated by oil and gas. The Russian Ministry of Energy forecasts that local power plants running on the renewable energy sources (RES) may not become economically efficient until 2025 or later. However, a research question arises: Is it possible to effectively implement RES projects in Russia without any state support? In order to answer this question, the authors need to assess the economic feasibility of seven scenarios for the construction of a solar power plant in the Orenburg region of Russia. The methodological basis of this work is the widely used in the energy sector classic method of investment analysis based on the calculation of discounted indicators: net present value (NPV), payback period (DPP) and internal rate of return (IRR) of the project. All our calculations are based on industry-specific initial capital investment estimates, energy storage equipment costs, and related annual operating costs. This led to the development of the scenarios on the basis of an analysis of the features of electricity and capacity generation in the Orenburg region, the existing options for joining the trading system of the energy market, energy storage applications, as well as the availability of the Russian government support and funding for the solar energy projects. Our results demonstrate that the economic feasibility of the development of renewable energy in Russia can become a reality. Out of the seven scenarios, three yielded the positive economic outcome (among them there were the two project scenarios without government support). These two projects featured the sale of electricity in retail markets and the installation of an additional energy storage system, despite an almost twofold increase in capital investments. The projects in question achieved the best economic results according to the three calculated criteria. In particular, the scenario that provided for the work on the retail market directly to the energy consumer receives an NPV of more than 1.5 times higher than other projects, an IRR of 10% and pays off at least 3 years faster. Achieving a positive economic result in the wholesale market was possible only in case of state support for the project. In addition, this scenario of the project numerically reached almost identical indicators, as in the case of selling energy on the retail market in the region where the power facility operates: NPV is almost 127 million rubles, IRR is within 13.9%, and DPP is 15 years. Other scenarios that do not provide for the use of energy storage systems or do not have state support for working in the wholesale market are not self-sustaining even during the 25-year life of energy equipment. These results might have practical significance and will be used in developing an approach to creating a profile of regions in terms of the advancements of renewable energy, as well as in developing strategies for the incentives of this sector in Russia.

Analysis of the additional cost of addressing per- and polyfluoroalkyl substance contamination from landfill leachate by reverse osmosis membranes in Thailand

Per- and polyfluoroalkyl substances (PFAS), persistent organic pollutants, have been found in landfill leachate (LL) and can lead to environmental contamination. Recently, more stringent global regulations to control the maximum levels of PFAS have forced landfill authorities to improve treatment technologies to meet higher effluent quality standards. This study analyzed the additional cost of the treatment process to remediate PFAS contamination from LL in Thailand using a two-pass reverse osmosis (RO) system, including pretreatment and the use of evaporation ponds. The total estimated LL volume from 111 sites of sanitary landfills was ascertained using the water balance method, and then the overall project cost in the form of the net present cost (NPC) was evaluated. The capital investment, expense, and related operating and maintenance costs over the project lifetime were taken into account. The results showed that the total estimated LL volume was 17.5 m3/yr. To handle this amount of LL, the NPCs of the RO system were found to be 577.9 mil. USD for the system with an evaporation pond and 391.9 mil. USD for the system without an evaporation pond. The treatment unit costs ranged from 1.72–2.71 USD/m3 for the system with an evaporation pond and ranged from 1.06 to 2.09 USD/m3 for the system without an evaporation pond, depending on the size of the landfills. Based on these results, technological, operational, financial, and regulatory policy recommendations are presented.

Data-Driven Robust Aircraft Assignment to Minimize Delay Propagation

Flight delays have a significant impact on an airline's operating cost including increased expenses for crew, fuel, and maintenance. Propagated delays due to late arriving aircraft contribute to 40% of all flight delays as reported by the Bureau of Transportation Statistics. The robust aircraft assignment problem is to assign tail numbers on scheduled arriving flights at an airport to scheduled departing flights at the same airport with the objective of minimizing propagated delays. In this paper, we propose a new data-driven approach for the robust aircraft assignment problem by formulating it as a balanced assignment problem between incoming and outgoing flights flown by the same aircraft type at a single airport. We consider both deterministic and stochastic versions of the aircraft assignment problem. In the deterministic case, we prove the optimality of the First-in-First-out (FIFO) assignment policy under two different performance measures, justifying the use of the FIFO policy as a benchmark. In the stochastic case, we show that the FIFO assignment policy is no longer optimal and propose the rFIFO and stochastic assignment formulations based on the mean and empirical distribution of arrival delay, respectively. We propose a data-driven approach to estimate the assignment costs by using empirical observations of arrival delays from prior years' flight records to compute the empirical propagated delay distribution. We propose a data-driven clustering method to account for factors such as originating airport, time of day, and aircraft type that affect the arrival delay distribution. These empirical cluster based aircraft assignment costs serve as an input to our stochastic assignment model. These assignment costs are then used to derive the optimal aircraft assignment for the rFIFO and stochastic assignment policies for an out of sample data set from 2018 for Delta at Atlanta airport. We show that both the rFIFO and stochastic assignment policies derived from the data-driven approach perform better than the benchmark FIFO assignment. We also show that for all Delta airline flights at Atlanta airport from July to September in 2018, the stochastic assignment policy yields a roughly 40% improvement in total actual propagated delay over the actual airline assignment while reducing the fraction of delayed flights due to propagated delays from 6.58% to 2.62%, thus potentially saving approximately 14 million dollars in flight delay related annual operating costs. We conclude that incorporating the stochastic nature of arrival delays in solving the robust aircraft assignment problem, and combining it with a data-driven approach can potentially help an airline significantly reduce its operating costs due to flight delays, improve passenger convenience and experience, and help the environment by reducing emissions.

Flight management enabling technologies for single pilot operations in Small Air Transport vehicles in the COAST project

Small Air Transport (SAT) is emerging as suitable transportation means in order to allow efficient travel over a regional range, in particular for commuters, based on the use of small airports and fixed wing aircraft with 5 to 19 seats, belonging to the EASA CS-23 category. The affordability of the SAT industry needs to be supported by the availability of new technological solutions allowing reducing the related operational costs while at the same time maintaining the required flight safety levels. In this framework, Clean Sky 2 Joint Undertaking funded the project COAST (Cost Optimized Avionics SysTem), which started in 2016 with the aim of tackling this challenge and delivering key technology enablers for the affordable cockpit and avionics, while also enabling the single pilot operations for small aircraft. The project activities cover several technologies and, among them, some selected ones, specifically addressing flight management, are considered in this paper, whose aim is the one of providing an outline of the design and implementation process status reached up to date, emphasizing the obtained results and the work to be done in the future activities expected to be performed in the project. The selected technologies here considered are the ones of tactical traffic separation and enhanced situational awareness, meteorological enhanced awareness, and pilot’s incapacitation emergency management. The paper, therefore, focuses on a selected cluster, from the overall framework of the COAST project, of SAT single pilot operations enabling technologies: Tactical Separation System (TSS), Flight Reconfiguration System (FRS), and Advanced Weather Awareness System (AWAS). In the paper, a description is first reported of the overall COAST project objectives, motivations and approach to the SAT vehicles cockpit design. Then, the implemented design process is outlined and the description of each of the above-indicated selected technologies is presented (the additional technologies considered in the COAST project are out of the scope of this paper). Based on that, for each of the considered systems (TSS, FRS, AWAS) the status of the design and implementation process is described and the next steps expected to be implemented in the project are outlined.

Assessment of the economic recycling potential of a glycolysis treatment of rigid polyurethane foam waste: A case study from Thailand

This research assessed the economic feasibility of recovering polyol from rigid polyurethane foam (RPUF) waste, collected from dismantled, discarded refrigerators, by a single-phase glycolysis recycling process using domestic crude glycerol (a byproduct of biodiesel production) as a transesterification agent. The study, conducted in Thailand, took into account benefits from the added value of the recovered product, the investment and related operating costs of the process, demand (the need for the recovered product) and supply (the amount of RPUF waste). The results showed that the production of recovered polyol from RPUF waste is economically feasible, with a net present value of 1,113,018 USD, an internal rate of return (IRR) of 22.9%, and a payback period of 4.4 years. Due to the high IRR, project investment should be attractive to both the government and private sector investors. In addition, a sensitivity analysis was conducted to assess the economic resilience of the process to uncertainties in key factors, including the prices of the machinery, recovered polyol, crude glycerol and stannous octoate, and the amount of RPUF waste available. The sensitivity analysis showed that the economic feasibility was most sensitive to the price of the recovered polyol, followed by the amount of RPUF waste and the prices of the machinery, crude glycerol and stannous octoate. Based on these results, technological, operational, financial, and regulatory policy recommendations were also presented.

Environment-Friendly School Bus Routing Problem With Heterogeneous Fleet: A Large-Scale Real Case

In the present study, we concentrate on the formulation and the exact solution of a specific vehicle routing problem with environmental concerns, which is a complex actual problem of staff service bus route planning for a university in a metropolitan city. Taking into account the air pollution related measures for representing the cost of environmental concerns in addition to the vehicle rental and fuel consumption related operational costs, we formulate a flow-based mixed integer linear program for the environment-friendly school bus routing problem specific to both homogeneous and heterogeneous vehicle fleets. We provide exact solutions to the instance sets we have designed specific to variants of the problem considering the fleet type, vehicle capacity, and maximum route length. Results from model based exact solutions for our formulations show up to 30% of reduction in the overall cost for the heterogeneous fleet case when compared to the homogeneous ones, and suggest a routing plan that enables the utilization of almost the entire capacity of all the buses assigned. We discuss in details the trade-offs between the cost items, travel times, and travel distances in composing a vehicle fleet considering the demand sprawled over the metropolitan area.

Optimal price and warranty decision for durable products in a competitive duopoly market

In recent years, product warranties have become a promotional or competing instrument for the manufacturer. Although providing a warranty will benefit both transaction sides, it is impractical for the manufacturer to provide an unlimited warranty to monopolize the market since the related operating costs will eventually exceed the profits. Accordingly, to provide a proper warranty is a crucial issue for the manufacturer. However, the related studies overly focused on the issue of price competition. Actually, with regard to durable products, market competition exists in price and post-sale service. Accordingly, price and warranty should be equally important when manufacturers make their integrated marketing strategies. A rational non-cooperative game model will be proposed in this study. A duopoly market is considered, and the two manufacturers will pay the royalty to obtain critical techniques and parts from a technical supplier to produce and sell highly substitutable products to a local market. The study indicates as follows: once the duopoly market equilibrium is reached, no single manufacturer can increase its profits by means of raising its price or extending its warranty term since the two manufacturers’ decisions always react to each other. Moreover, the manufacturers cannot fully transfer the increment of the royalty to customers by means of raising price. In addition, increasing demand's competitive intensity with respect to warranty will amplify a manufacturer's warranty elasticity if its warranty term is shorter than that of its rival. Due to the practicality of this issue, more managerial insights and suggestions are included in this study.

A novel pilot and full-scale constructed wetland study for glass industry wastewater treatment

Industrial wastewaters represent a serious threat to the environment due to their variable and complex composition. Though mostly mechanical systems are used for treatment of such wastewater, there is growing need for sustainable and cost-effective solutions, especially in low-income regions. In this study, a horizontal sub-surface flow Constructed Wetland (HSFCW) system was used for the first time to treat wastewater from a glass manufacturing industry in Iran. In order to de-risk the treatment approach, a pilot system consisting of a settling tank and a HSFCW was first tested for 4 months. The results of the pilot study were then used to build the full-scale CW system treating 10 m³/day. In general, the tested design proved to be very effective reaching high removal rates of BOD5, COD, and TSS (90, 90, and 99, respectively), as also for TN and TP (>90%). The high efficiency of the tested system allowed for the recycle and reuse of the treated effluent in the glass manufacturing processes, reducing this way the fresh water consumption in the glass industry and the related operational costs.

Priority and appropriateness of upper endoscopy out-patient referrals: Two-period comparison in an open-access unit

BackgroundIn the early 2000s we introduced a prioritization model for referrals based on involvement of primary care physicians (PCPs) and specialists. AimsAssess the application of that model of prioritisation, comparing gastroscopies performed 8 years apart, with respect to priority level, appropriateness and relevant endoscopic findings (REFs). MethodsThe studies included 247 and 354 out-patients, who had undergone gastroscopy in 2006 and in 2014, respectively. To reduce interspecialists variability, both studies were performed by the same specialist as investigator. ResultsIn both years, most patients were assigned low-priority referral by PCPs (78.6% and 75.1% respectively). The agreement PCPs versus specialist on referral priority was moderate in 2006 (0.60, Landis–Koch scale 0.41–0.60) and high in 2014 (0.81, Landis–Koch scale 0.81–1.00). In both years we observed a similar rate of inappropriateness: 27.5% and 27.1%, respectively. Due to multiple logistic regression, the odds ratio (OR) for REF increased when: (i) very high-priority referral versus nopriority referral was indicated (8.813 OR, p = 0.0012), (ii) referral followed the guidelines (9.29 OR, p<0.0001), and (iii) agreement of priority occurred (1.911 OR, p = 0.0308). ConclusionsOur findings highlighted that the issues of low-priority referrals should be addressed in order to discontinue gastroscopy overusing and reduce related operational costs.

Routing and wavelength assignment vs. EDFA reliability performance in optical backbone networks: An operational cost perspective

A failure in optical backbone network can cause tremendous consequences as a substantial number of connections often each carrying a large amount of data can be interrupted. Therefore, high reliability performance is essential for the network operators. Many existing works that aim at improving network reliability performance implicitly assume that the lifetime of devices is constant and independent of the traffic load. However, the reliability performance of a device is related to its occupancy. For example, the failure rate of erbium doped fiber amplifier (EDFA) can be expressed as a function of the number of amplified wavelengths. On the other hand, the choice of routing and wavelength assignment (RWA) algorithm impacts the link load and, as a consequence, can influence the number of EDFA failures in the network.In this paper we examine how RWA can impact the failure reparation related network operational costs. Several types of RWA approaches are considered, namely load-balancing, energy-awareness, and reliability-awareness. Among all the considered RWA algorithms, the reliability-aware RWA (RA-RWA) approach leverages on EDFA reliability profile to reduce the number of EDFA failures in the network and the related operational costs.The simulation results show that the RWA algorithm impacts in a significant way the operational costs caused by EDFA failures. The cost associated with reparation of an EDFA decreases by 7.8% (in case of RA-RWA) and increases by up to 40% (in case of a load-balancing approach) compared to the classical Shortest Path (SP) approach. Moreover, the cost caused by connection rerouting due to link unavailability triggered by EDFA failure exhibits a 20% decrease (RA-RWA) and up to 94% increase (energy-aware algorithm). We also analyze some key network performance metrics that may be affected by RWA, including blocking probability, link occupancy distribution, and path length.

Environmental and economic implications of food safety interventions: Life cycle and operating cost assessment of antimicrobial systems in U.S. beef packing industry

Abstract Antimicrobial systems in the U.S. beef packing industry are key treatments to improve the microbiological safety of beef products. However, product loss due to discoloration and use of chemicals, energy, and water have environmental and cost implications. This study compared environmental life cycle impacts and relative operating costs among three scenarios of antimicrobial systems currently applied in the commercial U.S. beef packing industry. Key differences between the three scenarios are the dominant use of antimicrobial chemicals, steam, and hot water pasteurization. Findings reveal that antimicrobial systems featured with chemicals result in greater human toxicity, ecotoxicity, and eutrophication impacts while antimicrobial systems featured with steam or hot water pasteurization lead to higher global warming and energy depletion. Contributions within each antimicrobial system were evaluated by: 1) seven components and 2) four intervention steps. Results show that antimicrobial chemical, wastewater treatment, and natural gas use are the three leading contributors across all environmental impacts. Evaluating environmental impact contributions of intervention steps helps target reduction goals in primary intervention steps and reveals potential opportunities for further impact reductions. A relative operating cost analysis of each scenario found revenue loss from discolored products in antimicrobial systems applying thermal pasteurization is the most significant contributor, resulting in higher operating costs than that of antimicrobial system featured with chemicals. This study provides a systematic assessment regarding environmental and cost impacts of three scenarios of antimicrobial systems. Also it can help guide process optimization, and provide a baseline for comparison with future new antimicrobial systems.

Energy-optimized versus cost-optimized design of high-performing dwellings: The case of multifamily buildings

Living in multifamily buildings is very common in Italy, and it is important to optimize the design strategies to minimize the energy demand of these buildings and their related operational costs. This is particularly important for low-income tenants and is pursued by many social housing developments where a good energy performance design is reached. In this work, a simulation-based optimization methodology that combines the use of TRNSYS with GenOpt is applied to minimize two objective functions—the annual primary energy demand and the operational energy cost—in different system technology scenarios, and to verify the differences between energy-optimized design and cost-optimized design in a Northern Italy climate. The study is performed on a typical floor of a real multifamily building for social housing. The envelope optimization demonstrates a potential reduction of the energy demand and cost for heating and cooling of more than 35%. The relationship between optimal solutions, system technology scenarios, and optimization objectives is deeply analyzed. It is possible to find a set of design solutions that is optimal for all analyzed scenarios. This provides a set of design alternatives that is close to the environmental optimum and is able to reduce low-income tenants' vulnerability.

Techno-economical Analysis based on a Parametric Computational Evaluation for decision process on envelope technologies and configurations

Energy saving is crucial for existing buildings which is present a huge potential of improvement by a strong energy retrofitting. Often, the existing envelope components are not adequately insulated and deep refurbishment is required to comply current regulations to improve energy efficiency and address Nearly Zero Energy Building (NZEB) goals. The strategies to enhance buildings energy performance involve heating and cooling demands strongly dependent by envelope quality (i.e. insulation, thermal mass, internal gain storage capacity and solar heat gains exploitation). Commonly, the suggested main retrofit interventions on envelope are glazed surfaces replacement, Solar Heat Gain Coefficient (SHGC) reduction and thermal transmittance (U value) improvement by additional insulation layers or even components replacement. However, it is worthy to note that the resulting thickness of the external envelope and the payback time of the interventions are important supports for decision-making. The environmental issue related to CO2 emissions during the operational phase of the building is encompassed into the standard energy certification of the asset and the conversion factors to define fuels’ impacts are available and updated. However, the calculation excludes the environmental impact due to energy used for materials’ production and few official information sources provide accredited values, e.g. the Environmental Product Declaration (EPC). Going towards a Zero Energy Building, which reduces its environmental impact during the running phase, embodied energy claims an increasing weight. Thus, materials and components with low embodied energy should be favoured and endorsed. For this reason, the most influential rating systems worldwide available for building sustainability assessment (e.g. LEED, BREEAM, etc.) updated their checklists including criteria related to reduced energy for extraction, production and materials transportation on the field.The technological optioneering of envelope solutions to achieve both energy efficiency and economic affordability is inevitably based on and supported by multicriteria assessment frameworks. These frameworks should include energy, environmental and economic parameters to define the technological suitability in different climate conditions identifying accurate optimization points, e.g. thickness of the insulation layer or heat storage capacity, considering energy saving and management costs in the life cycle. When actual optimization processes are required, computational parametric tools support to ease the options’ performance comparison and to compute different combinations. Nowadays some tools are available into the main authoring software on the energy simulation market. Although different tools could be adopted, the need of transparency and custom workflows is crucial. In the present research, a specific multi-criteria methodological approach enables to outline a synoptic diagram for each considered climate to compare the envelope technological solutions by aggregating LCA (Life Cycle Analysis) and LCC (Life Cycle Cost) factors. For LCA, Embodied Energy (EE) of the envelope materials and Primary Energy (EP) used during the running phase have been considered. For LCC Investment Cost (C) of the materials to enhance a baseline performance and related operational costs of the building based on Net Present Value (NPV) and Discounted Payback Period (DPP) have been adopted.The present study focuses as first on the construction coherency of different technologies used to define the external envelope of a test room, able to manage the energy flows resulting from different external conditions. Subsequently the definition of the technological basket, a parametric analysis based on reducing thermal losses and increase solar gains has been performed defining the most suitable technologies and façade configuration in three representative climate conditions at national level by calculating heating and cooling demand and related primary energy.

Fact or Fraud?

Epidemic - a widespread occurrence of an infectious disease in a community at a particular time - outbreak, scourge, plague.About 1976 concerns emerged in Australia about the potential for new technologies to seriously reduce employment. The debate reached a peak in 1978 when industrial action taken by the Australian Telecommunications Employees Association (ATEA) threatened to shut down the Australian telecommunications network.From 1975 growth in calls to the directory assistance service rocketed as did the related operating costs. To maintain the quality of customer service and contain operating costs, Telecom began to deploy a nation-wide computer- based directory assistance system (DAS/C) from 1982. In 1983 an unexpected medical syndrome arose in one of Telecom's directory assistance centres.Over the next three years, the syndrome rapidly spread through other directory assistance centres, other areas of Telecom and some areas of the public service. The media, academia, legal practitioners and others attracted to the "problem" generally accepted the union view that the DAS/C system was the cause and the syndrome was labelled Repetitive Strain Injury (RSI). Medical costs and compensation claims mounted reaching $130 million in 1989.While RSI has become a well-known syndrome over the last 40 years, no outbreaks of the extent and severity experienced in Telecom appear to have been recorded over that period anywhere in the world. There still appears to be little scientific evidence of the link between the injury of the reported scale and the workplace.This is the story of the rise of the RSI phenomena in Telecom over the period 1983-86.

Fact or Fraud?

Epidemic - a widespread occurrence of an infectious disease in a community at a particular time - outbreak, scourge, plague.About 1976 concerns emerged in Australia about the potential for new technologies to seriously reduce employment. The debate reached a peak in 1978 when industrial action taken by the Australian Telecommunications Employees Association (ATEA) threatened to shut down the Australian telecommunications network.From 1975 growth in calls to the directory assistance service rocketed as did the related operating costs. To maintain the quality of customer service and contain operating costs, Telecom began to deploy a nation-wide computer- based directory assistance system (DAS/C) from 1982. In 1983 an unexpected medical syndrome arose in one of Telecom's directory assistance centres.Over the next three years, the syndrome rapidly spread through other directory assistance centres, other areas of Telecom and some areas of the public service. The media, academia, legal practitioners and others attracted to the "problem" generally accepted the union view that the DAS/C system was the cause and the syndrome was labelled Repetitive Strain Injury (RSI). Medical costs and compensation claims mounted reaching $130 million in 1989.While RSI has become a well-known syndrome over the last 40 years, no outbreaks of the extent and severity experienced in Telecom appear to have been recorded over that period anywhere in the world. There still appears to be little scientific evidence of the link between the injury of the reported scale and the workplace.This is the story of the rise of the RSI phenomena in Telecom over the period 1983-86.