The Safe Schools Declaration of 2015 is an inter-governmental political agreement signed by several countries designed to protect the schooling of the school-aged population during armed conflicts.Yet,in countries whe...The Safe Schools Declaration of 2015 is an inter-governmental political agreement signed by several countries designed to protect the schooling of the school-aged population during armed conflicts.Yet,in countries where civil war erupted,schools were demolished.Several school-aged children were either forcibly recruited by governments or coerced by rebel groups to serve in armed fights.As a result,several children were deprived of their education and have remained suffering from deep psychological scars.The central question of the study is:What kind of sustainability-driven school buildings can be initiated in countries that are now enduring peace so that the learning environments are more comfortable and improve the well-being of the war-impacted children and school employees?After reviewing the literature,a strategic conceptual framework that incorporated the synergistic relationship between economic,social,and environmental aspects of sustainability was initiated to map out sustainable school buildings.In short,the conceptual framework proposed to construct school buildings in some of the war-affected developing countries includes assembling cost-efficiency and eco-effectiveness inputs,using renewable energy sources powered by natural sunlight,collecting rainwater in mud cisterns,reducing emissions of carbon oxides,and empowering the local community to be the main actors to design sustainable buildings during the preconstruction,construction,and post-construction stages to serve as learning spaces for the war-affected occupants and their neighborhoods.展开更多
In this research endeavor,undergraduate senior civil engineering students from California State University,Northridge,under the supervision of Dr.Tadeh Zirakian and Dr.David Boyajian,introduced a design that maximizes...In this research endeavor,undergraduate senior civil engineering students from California State University,Northridge,under the supervision of Dr.Tadeh Zirakian and Dr.David Boyajian,introduced a design that maximizes sustainability of an infrastructure while limiting cost.The design consisted of a residential home with a two-story structure and steel moment resisting frame.A modern open concept theme was implemented that followed ASCE 7 safety features while incorporating multiple LEED(Leadership in Energy and Environmental Design)certified features to achieve high sustainability.The purpose of this study was to conduct a comparative cost analysis between a traditional and LEED supported design.Findings using RS Means software showed that a structure with LEED features(estimated at$876,357)was 46%more costly than one without LEED features($600,000);however,LEED implementation led to substantial cost savings over a nine-year period,ultimately reducing cost over time by$176,000.Completion of this project achieved several educational endeavors,namely enabling the students to apply their acquired engineering skills to real life scenarios and promoting the practice of communication and sharing of ideas in a diverse team setting.It is hoped that future generations will be able to benefit from the review of this study process and be able to apply similar models to inspire sustainable and cost-effective designs.展开更多
AIM:To determine the short-term cost-utility of mo-lecular adsorbent recirculating system(MARS) treatment in acute liver failure(ALF).METHODS:A controlled retrospective study was conducted with 90 ALF patients treated...AIM:To determine the short-term cost-utility of mo-lecular adsorbent recirculating system(MARS) treatment in acute liver failure(ALF).METHODS:A controlled retrospective study was conducted with 90 ALF patients treated with MARS from 2001 to 2005.Comparisons were made with a historical control group of 17 ALF patients treated from 2000 to 2001 in the same intensive care unit(ICU) specializing in liver diseases.The 3-year outcomes and number of liver transplantations were recorded.All direct liver disease-related medical expenses from 6 mo before to 3 years after ICU treatment were determined for 31 MARS patients and 16 control patients.The health-related quality of life(HRQoL) before MARS treatment was estimated by a panel of ICU doctors and after MARS using a mailed 15D(15-dimensional generic healthrelated quality of life instrument) questionnaire.The HRQoL,cost,and survival data were combined and the incremental cost/quality-adjusted life years(QALYs) was calculated.RESULTS:In surviving ALF patients,the health-related quality of life after treatmeant was generally high and comparable to the age-and gender-matched general Finnish population.Compared to the controls,the average cost per QALY was considerably lower in the MARS group(64 732€ vs 133 858€) within a timeframe of 3.5 years.The incremental cost of standard medical treatment alone compared to MARS was 10 928€,and the incremental number of QALYs gained by MARS was 0.66.CONCLUSION:MARS treatment combined with standard medical treatment for ALF in an ICU setting is more cost-effective than standard medical treatment alone.展开更多
Crossover designs are well-known to have major advantages when comparing the effects of various non-curative treatments. We compare efficiencies of several crossover designs along with the Balaam’s design with that o...Crossover designs are well-known to have major advantages when comparing the effects of various non-curative treatments. We compare efficiencies of several crossover designs along with the Balaam’s design with that of a parallel group design pertaining to longitudinal studies where event time can only be measured in discrete time intervals. With equally sized sequences, the parallel group design results in the greater efficiency if the number of time periods is small. However, the crossover and Balaam’s designs tend to be more efficient as the study duration increases. The degree to which these designs add efficiency depends on the baseline hazard function and effect size. Additionally, we incorporate different cost considerations at the subject level when comparing the designs to determine the most cost-efficient design. Researchers might consider the crossover or Balaam’s design more efficient if the duration of the study is long enough, especially if the costs of applying the baseline treatment are higher.展开更多
With the steady growth of traffic volume in core networks,it is predicted that future optical network communication will be constrained mainly by cost and power consumption.Thus,for Internet sustainability,it will be ...With the steady growth of traffic volume in core networks,it is predicted that future optical network communication will be constrained mainly by cost and power consumption.Thus,for Internet sustainability,it will be necessary to ensure cost and power efficiency in optical networks.The aims of this study are(i)to identify the main sources of cost and power consumption in fixed-grid(SLR and MLR)and flexi-grid(OFDM)optical networks,and(ii)to compare techniques for improving cost and power efficiency in SLR/MLR-and OFDM-based networks.To this end,we conducted a comparative analysis of cost and power efficiency for the OFDM-and MLR/SLR-based networks,and considering realistic networks,evaluated the cost and power consumed by different components in the optical layer.Our results show that(i)OFDM-based networks outperform those based on MLR/SLR in terms of both cost and power-efficiency,(ii)the extra equipment cost incurred due to under-utilization of spectrum is reduced by switching to a flexi-grid network,(iii)lower power consumption per bit is obtained when the networking solution ensures a finer bit-rate granularity,and(iv)there exists a power and spectrum minimization trade-off that is network characteristic dependent.展开更多
Quantum dots are ideally suited for color conversion in light emitting diodes owing to their spectral tunability,high conversion efficiency and narrow emission bands.These properties are particularly important for dis...Quantum dots are ideally suited for color conversion in light emitting diodes owing to their spectral tunability,high conversion efficiency and narrow emission bands.These properties are particularly important for display backlights;the highly saturated colors generated by quantum dots justify their higher production cost.Here,we demonstrate the benefits of a hybrid remote phosphor approach that combines a green-emitting europium-doped phosphor with red-emitting CdSe/CdS core/shell quantum dots.Different stacking geometries,including mixed and separate layers of both materials,are studied at the macroscopic and microscopic levels to identify the configuration that achieves maximum device efficiency while minimizing material usage.The influence of reabsorption,optical outcoupling and refractive index-matching between the layers is evaluated in detail with respect to device efficiency and cost.From the findings of this study,general guidelines are derived to optimize both the cost and efficiency of CdSe/CdS and other(potentially cadmium-free)quantum dot systems.When reabsorption of the green and/or red emission is significant compared to the absorption strength for the blue emission of the pumping light emitting diode,the hybrid remote phosphor approach becomes beneficial.展开更多
文摘The Safe Schools Declaration of 2015 is an inter-governmental political agreement signed by several countries designed to protect the schooling of the school-aged population during armed conflicts.Yet,in countries where civil war erupted,schools were demolished.Several school-aged children were either forcibly recruited by governments or coerced by rebel groups to serve in armed fights.As a result,several children were deprived of their education and have remained suffering from deep psychological scars.The central question of the study is:What kind of sustainability-driven school buildings can be initiated in countries that are now enduring peace so that the learning environments are more comfortable and improve the well-being of the war-impacted children and school employees?After reviewing the literature,a strategic conceptual framework that incorporated the synergistic relationship between economic,social,and environmental aspects of sustainability was initiated to map out sustainable school buildings.In short,the conceptual framework proposed to construct school buildings in some of the war-affected developing countries includes assembling cost-efficiency and eco-effectiveness inputs,using renewable energy sources powered by natural sunlight,collecting rainwater in mud cisterns,reducing emissions of carbon oxides,and empowering the local community to be the main actors to design sustainable buildings during the preconstruction,construction,and post-construction stages to serve as learning spaces for the war-affected occupants and their neighborhoods.
基金The student research team would like to express their sincere appreciation for the support provided by Dr.Tadeh Zirakian and Dr.David Boyajian,professors of Civil Engineering in the Department of Civil Engineering and Construction Management at California State University,Northridge,U.S.A.
文摘In this research endeavor,undergraduate senior civil engineering students from California State University,Northridge,under the supervision of Dr.Tadeh Zirakian and Dr.David Boyajian,introduced a design that maximizes sustainability of an infrastructure while limiting cost.The design consisted of a residential home with a two-story structure and steel moment resisting frame.A modern open concept theme was implemented that followed ASCE 7 safety features while incorporating multiple LEED(Leadership in Energy and Environmental Design)certified features to achieve high sustainability.The purpose of this study was to conduct a comparative cost analysis between a traditional and LEED supported design.Findings using RS Means software showed that a structure with LEED features(estimated at$876,357)was 46%more costly than one without LEED features($600,000);however,LEED implementation led to substantial cost savings over a nine-year period,ultimately reducing cost over time by$176,000.Completion of this project achieved several educational endeavors,namely enabling the students to apply their acquired engineering skills to real life scenarios and promoting the practice of communication and sharing of ideas in a diverse team setting.It is hoped that future generations will be able to benefit from the review of this study process and be able to apply similar models to inspire sustainable and cost-effective designs.
基金Supported by Scientific grants from the Helsinki University Central Hospital Research Fund (EVO) and the Finnish Office for Health Technology Assessment
文摘AIM:To determine the short-term cost-utility of mo-lecular adsorbent recirculating system(MARS) treatment in acute liver failure(ALF).METHODS:A controlled retrospective study was conducted with 90 ALF patients treated with MARS from 2001 to 2005.Comparisons were made with a historical control group of 17 ALF patients treated from 2000 to 2001 in the same intensive care unit(ICU) specializing in liver diseases.The 3-year outcomes and number of liver transplantations were recorded.All direct liver disease-related medical expenses from 6 mo before to 3 years after ICU treatment were determined for 31 MARS patients and 16 control patients.The health-related quality of life(HRQoL) before MARS treatment was estimated by a panel of ICU doctors and after MARS using a mailed 15D(15-dimensional generic healthrelated quality of life instrument) questionnaire.The HRQoL,cost,and survival data were combined and the incremental cost/quality-adjusted life years(QALYs) was calculated.RESULTS:In surviving ALF patients,the health-related quality of life after treatmeant was generally high and comparable to the age-and gender-matched general Finnish population.Compared to the controls,the average cost per QALY was considerably lower in the MARS group(64 732€ vs 133 858€) within a timeframe of 3.5 years.The incremental cost of standard medical treatment alone compared to MARS was 10 928€,and the incremental number of QALYs gained by MARS was 0.66.CONCLUSION:MARS treatment combined with standard medical treatment for ALF in an ICU setting is more cost-effective than standard medical treatment alone.
文摘Crossover designs are well-known to have major advantages when comparing the effects of various non-curative treatments. We compare efficiencies of several crossover designs along with the Balaam’s design with that of a parallel group design pertaining to longitudinal studies where event time can only be measured in discrete time intervals. With equally sized sequences, the parallel group design results in the greater efficiency if the number of time periods is small. However, the crossover and Balaam’s designs tend to be more efficient as the study duration increases. The degree to which these designs add efficiency depends on the baseline hazard function and effect size. Additionally, we incorporate different cost considerations at the subject level when comparing the designs to determine the most cost-efficient design. Researchers might consider the crossover or Balaam’s design more efficient if the duration of the study is long enough, especially if the costs of applying the baseline treatment are higher.
文摘With the steady growth of traffic volume in core networks,it is predicted that future optical network communication will be constrained mainly by cost and power consumption.Thus,for Internet sustainability,it will be necessary to ensure cost and power efficiency in optical networks.The aims of this study are(i)to identify the main sources of cost and power consumption in fixed-grid(SLR and MLR)and flexi-grid(OFDM)optical networks,and(ii)to compare techniques for improving cost and power efficiency in SLR/MLR-and OFDM-based networks.To this end,we conducted a comparative analysis of cost and power efficiency for the OFDM-and MLR/SLR-based networks,and considering realistic networks,evaluated the cost and power consumed by different components in the optical layer.Our results show that(i)OFDM-based networks outperform those based on MLR/SLR in terms of both cost and power-efficiency,(ii)the extra equipment cost incurred due to under-utilization of spectrum is reduced by switching to a flexi-grid network,(iii)lower power consumption per bit is obtained when the networking solution ensures a finer bit-rate granularity,and(iv)there exists a power and spectrum minimization trade-off that is network characteristic dependent.
基金the IWT-Vlaanderen(Agency for Innovation by Science and Technology in Flanders)for a scholarship(111597 and 121024)support by the European Commission via the Marie-Sklodowska Curie action Phonsi(H2020-MSCA-ITN-642656)+2 种基金the Belgian Science Policy office(IAP 7.35,photon-ics@be)Ghent University(GOA 01G01513)the IWT-Vlaanderen for the SBO-IWT grant LumiCoR(SBO130030).
文摘Quantum dots are ideally suited for color conversion in light emitting diodes owing to their spectral tunability,high conversion efficiency and narrow emission bands.These properties are particularly important for display backlights;the highly saturated colors generated by quantum dots justify their higher production cost.Here,we demonstrate the benefits of a hybrid remote phosphor approach that combines a green-emitting europium-doped phosphor with red-emitting CdSe/CdS core/shell quantum dots.Different stacking geometries,including mixed and separate layers of both materials,are studied at the macroscopic and microscopic levels to identify the configuration that achieves maximum device efficiency while minimizing material usage.The influence of reabsorption,optical outcoupling and refractive index-matching between the layers is evaluated in detail with respect to device efficiency and cost.From the findings of this study,general guidelines are derived to optimize both the cost and efficiency of CdSe/CdS and other(potentially cadmium-free)quantum dot systems.When reabsorption of the green and/or red emission is significant compared to the absorption strength for the blue emission of the pumping light emitting diode,the hybrid remote phosphor approach becomes beneficial.