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1.
The present study was conducted to share the experience of promoting fish production and marketing from the Tendaho Reservoir of the Afar region, Ethiopia. The study results indicate the reservoir is serving its purpose, namely to generate gainful employment for the pastoralist youth and to create sustainable livelihoods and sources of income for the pastoralist‐fishermen of the Afar region. Further, the reservoir fish production has improved the nutrition and food security status of children. It also created a new business entry for hotels and restaurants in the area. Fishermen in the study areas, however, face problems getting the required support for such efforts, in the form of training in fish post‐harvest practices. The present study also indicates dried catfish marketing should be targeted in the short run to address the substantial fish spoilage observed in the high‐production hot season. Dried catfish marketing is highly recommended for the Afar region since it is well adapted to the climate of the study area, noting the product is less perishable and can be sold throughout the country. Dried catfish marketing is also expected to address the problem of gender inclusiveness, an issue clearly missing in the fish production system in the study areas.  相似文献   
2.
IT firms vary in their performance to improve the environmental sustainability of their own operations and in their ability to provide products and solutions that enable and transform the environmental sustainability of other industries. In the parlance of the balanced scorecard, performance has two dimensions, that is, “drivers” and “outcomes”. The drivers, also known as leading performance indicators, refer to learning and innovation, processes, and customer value propositions. The outcomes, also known as lagging performance indicators, refer to financial results. This study has developed and validated an instrument to measure the environmentally sustainable IT performance (eSITP) drivers. We established the nomological network of the eSITP by drawing from several theoretical domains in the areas of innovation antecedents and values, balanced performance measurement and IT and eco-sustainability. Based on a survey of 133 IT firms, we developed and validated a four-dimension, 17 items eSITP instrument covering eco-learning, eco-process, eco-brand and eco-value governance. The instrument is validated by following a seven step rigorous process. The paper breaks new ground from both research and practice perspectives. The instrument makes it easier for other researchers who wish to explain the leading (drivers) and lagging (outcomes) of IT firms’ environmental sustainability and for IT business managers who want to improve their environmental sustainability performance.  相似文献   
3.
This paper presents the results of a Norwegian power system analysis. An energy system analysis model based on linear programming is used for modelling and optimisation. The analyses cover a number of scenarios where the studied system is subjected to changes by introducing other renewable energy sources, energy conservation measures and measures to promote renewable energy. The study shows that due to a combination of cheap hydropower and high investment costs, it is quite difficult for new generation units to be profitable. This is also true during periods of low precipitation where the system tends to survive on imported power instead of investing in new generation units. However, this does not apply to energy conservation measures that easily enter the system. On the other hand, biomass based CHP, wind power and wave power could be viable if measures are introduced to promote their use. Most of the scenarios show a high potential for reducing global emissions.  相似文献   
4.
Ceria, pure or doped, is an important electrolyte material in solid oxide fuel cells, catalysts, and plutonium surrogates. Even though ceria is a widely studied material, its coprecipitation with the most common doping element, gadolinium, remains mostly overlooked. Here, we present a comprehensive study of gadolinium–cerium oxalates prepared by coprecipitation of gadolinium (III) and cerium (III) salts by oxalic acid under different reaction conditions and element ratios. For this purpose, we assessed the effects of basic precipitation conditions on the final oxalate size, shape, and conversion into the corresponding oxides. The results showed that coprecipitation with oxalic acid yields and ideal solid solution, which translates into the oxides. This low-cost and straightforward synthetic route provides then high-quality solid solutions of Ge–Gd in the oxide lattice. Thus, this approach has a high industrialization potential, with significant advantages over hydrolysis or hydrothermal techniques.  相似文献   
5.
This paper presents some of the results of a power system analysis for Chile. The two major Chilean electric systems are roughly modelled and optimized using a linear programming method with the option to integrate renewable energy sources like wind power, solar power, mini-hydropower and biomass-fired power and also “municipal waste”. A total of four different scenarios are outlined: reference system, new production units, gas and coal price variations and a policy measure to encourage power production based on renewable energy. The objective of the scenarios was to illustrate under what conditions integration of the different energy sources in the existing production system is possible. The study shows that even under current conditions, mini-hydro and waste to energy plants are economically viable. Wind power might be interesting alternatives if policy instrument measures are applied. On the other hand, it is hard for the other energy sources to enter the system even when higher price levels of gas and coal are applied. The system is more sensitive to coal price increases than to gas price increases and this mainly encourages CO2 emission reduction.  相似文献   
6.
BACKGROUND: The aim of this experimental study was to evaluate the risk of tumor recurrence after laparoscopic cecal resection (LCR) of colonic carcinoma in the rat. METHODS: The experimental cancer consisted of one million cells (DHK/K12), incorporated in an extracellular matrix, placed and secured to the cecal serosa in 110 BD9 rats. Four weeks later, all animals were reoperated through a laparotomy to control tumor growth, and animals with diffuse carcinomatosis were excluded. Eligible animals were randomized either to laparoscopic cecal resection (group LCR, n = 10), to open resection (group OCR, n = 13), or to a control group without resection (group C, n = 13). Resection was always considered as macrocopically complete. All animals were killed 4 weeks after the resection to determine the tumor recurrence and quantify carcinomatosis. RESULTS: We noted diffuse carcinomatosis in 70% of rats in groups C and LCR versus 23% in group OCR (p = 0.038). For tumors noted as S- (not extending outside the serosa), diffuse carcinomatosis was observed in all animals of group C (3 of 3), in 6 of 8 in group LCR, and 0 of 6 in group OCR (p = 0.004). The rate of port site or incisional metastases was not significantly different between groups. CONCLUSIONS: These preliminary results demonstrated the deleterious impact of the laparoscopy for resection of large bowel malignancy. LCR increased significantly the incidence of a diffuse carcinomatosis even when performed for locally noninvasive tumors (S-).  相似文献   
7.
Regions with densely concentration of industries and district heating systems (DHS) could be interesting study object from the light of an integrated heat market on local basis. System analysis with a widened system boundary could be used as an approach to evaluate the benefit of an integrated heat supply system. In this study, an energy system model consisting of totally seven different participants is designed and the optimization results of the system analysis are presented. With applied data and assumptions, the study shows that a significant amount of the heat demand within two sub‐systems can be covered by heat supply from the heat market (the entire heat comes from two industries). Shadow prices, which can be used for heat pricing, indicate the advantage of an integrated system. The system cost reduction through integration and the availability of several actors with diverse energy supply system, makes the region under study an interesting area to prove a locally deregulated heat market. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
8.
The purpose of this research was to model the kinetics of adsorption of 1-methylcyclopropene (1-MCP) in apple fruit and non-target solid materials found in apple storage rooms. The process was described by Fick’s second law of diffusion of the gas through the pores of the material coupled with adsorption kinetics of the gas on the material’s binding sites. A finite element formulation of the model, describing the diffusion and adsorption mechanisms separately, was first developed. The values of the relevant parameters were estimated based on headspace measurements of the decrease of 1-MCP in jars containing the different materials. The headspace concentration of 1-MCP was measured using gas chromatography. Apple fruit (Golden Delicious and Jonagold) and the following bin construction materials were investigated: high density polyethylene (HDPE), oak, poplar wood and card lining. The range in the magnitude of the diffusion coefficient, adsorption coefficient, and concentration of active sites in the various solids was 10,000-, 8-, and 30-fold, respectively.  相似文献   
9.
Extreme confinement of electromagnetic waves and mechanical displacement fields to nanometer dimensions through plasmonic nanostructures offers unprecedented opportunities for greatly enhanced interaction strength, increased bandwidth, lower power consumption, chip-scale fabrication, and efficient actuation of mechanical systems at the nanoscale. Conversely, coupling mechanical oscillators to plasmonic nanostructures introduces mechanical degrees of freedom to otherwise static plasmonic structures thus giving rise to the generation of extremely large resonance shifts even for minor position changes. This nanoscale marriage of plasmonics and mechanics has led to the emergence of a new field of study called plasmomechanics that explores the fundamental principles underneath the coupling between light and plasmomechanical nanoresonators. In this review, both the fundamental concepts and applications of plasmomechanics as an emerging field of study are discussed. After an overview of the basic principles of plasmomechanics, the active tuning mechanisms of plasmonic nano-mechanical systems are extensively analyzed. Moreover, the recent developments on the practical implications of plasmomechanic systems for such applications as biosensing and infrared detection are highlighted. Finally, an outlook on the implications of the plasmomechanical nanosystems for development of point-of-care diagnostic devices that can help early and rapid detection of fatal diseases are forwarded.  相似文献   
10.
Wireless Personal Communications - Through the use of UAV, the functional lifetime of WSN can be elongated in exchange for higher data delivery latency as the UAV replaces the multi-hop...  相似文献   
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