Electric boilers (EBs) provide an alternative method to deal with the accommodation of curtailed wind power. To pursue the minimum coal consumption in the system, a dispatching model integrating combined-heat-and-powe...Electric boilers (EBs) provide an alternative method to deal with the accommodation of curtailed wind power. To pursue the minimum coal consumption in the system, a dispatching model integrating combined-heat-and-power (CHP) plants and EBs in different locations is developed, and the penalty of wind power curtailment and cost of EB employment are also incorporated in the model. The transmission loss and transportation lag of heat-supply network as well as the elasticity of heat load are considered in this paper. A kind of constrained programming with stochastic and fuzzy parameters is applied to deal with the uncertainties. A case in East Inner Mongolia in China demonstrates that the EBs are able to absorb curtailed wind power and supply the heat. The results indicate that the utility of EBs in the primary or secondary heat-supply network to accommodate curtailed wind power is mainly related to the efficiency of heat transmission and the elasticity of heat load.展开更多
Purpose: There is a significant rise in mortality rates from breast and cervical cancers in Low- and Middle-Income Countries. In Ghana, approximately 4482 women are diagnosed with these diseases at advanced stages. Un...Purpose: There is a significant rise in mortality rates from breast and cervical cancers in Low- and Middle-Income Countries. In Ghana, approximately 4482 women are diagnosed with these diseases at advanced stages. Unfortunately, the early detection rate for these cancers is low compared to other women’s health services. This situation underscores the need to identify the locations of reproductive-age women who have not been screened for these cancers, to implement targeted public health interventions. This study aims to pinpoint these women’s locations for tailored interventions. Method: Bivariate analysis assessed the relationship between the independent and outcome variables. Hot spot analysis and Kriging Ordinary interpolation were employed to pinpoint the locations of these women. Results: Breast cancer examination and cervical cancer test rates were low, with a strong association between the two screening services. Several significant variables were identified: place of residence (p Conclusion: Low participation in these screening services was related to women’s age and the outreach efforts of fieldworkers. Breast and cervical cancer screenings are interconnected and could be combined to improve attendance rates. The Community-based Health Planning and Services (CHPS) implementation strategy could be cost-effective for screening women through targeted interventions, especially in identified clusters.展开更多
针对燃气-蒸汽联合循环且余热锅炉不补燃的热电联产机组(combined power and heat unit,CHP),首先,基于能量守恒建立天然气流量与电力电压、电流的等值关系,进而考虑功率进行变换的物理特性,构建CHP的气电变换等效电路;考虑功率进行传...针对燃气-蒸汽联合循环且余热锅炉不补燃的热电联产机组(combined power and heat unit,CHP),首先,基于能量守恒建立天然气流量与电力电压、电流的等值关系,进而考虑功率进行变换的物理特性,构建CHP的气电变换等效电路;考虑功率进行传递、释放的物理特性,构建CHP的气热转换、烟气排放及运行热损失方程;据此,确立CHP的物理特性等值模型,并定义该模型“以热定电”和“以电定热”策略下的控制参量。其次,利用牛顿法和管网水力计算基本原理,推导电潮流和气、热能流的修正方程及其雅可比元素表达式,提出计及CHP固有特性参数随系统运行状态变化的气-电-热混合能流统一分析方法。最后,通过具有不同CHP控制策略的气-电-热混合系统,验证所提方法的有效性及可行性。展开更多
The present paper analyses a case study of the application of dynamic energy simulation on the energy efficiency improvement process of an existing commercial building,the retrofit of a CHP machine for the combined ge...The present paper analyses a case study of the application of dynamic energy simulation on the energy efficiency improvement process of an existing commercial building,the retrofit of a CHP machine for the combined generation of heat and power is analysed.Great attention is dedicated to the correct sizing of the CHP/CCHP plant both in term of energy efficiency and economic viability.A detailed building model is developed and used,through dynamic building simulation,to identify the potential energy and economic savings achievable with the installation of a CHP/CCHP sized based on the results of the simulation itself.The work proves the usefulness of dynamic energy simulation as an evaluation tool for retrofits of CHP plants and provides suggestions on the correct sizing of CHP equipment.It is also meant to prove what could be achieved if those kinds of analysis were carried out during the design of the building.展开更多
文摘Electric boilers (EBs) provide an alternative method to deal with the accommodation of curtailed wind power. To pursue the minimum coal consumption in the system, a dispatching model integrating combined-heat-and-power (CHP) plants and EBs in different locations is developed, and the penalty of wind power curtailment and cost of EB employment are also incorporated in the model. The transmission loss and transportation lag of heat-supply network as well as the elasticity of heat load are considered in this paper. A kind of constrained programming with stochastic and fuzzy parameters is applied to deal with the uncertainties. A case in East Inner Mongolia in China demonstrates that the EBs are able to absorb curtailed wind power and supply the heat. The results indicate that the utility of EBs in the primary or secondary heat-supply network to accommodate curtailed wind power is mainly related to the efficiency of heat transmission and the elasticity of heat load.
文摘Purpose: There is a significant rise in mortality rates from breast and cervical cancers in Low- and Middle-Income Countries. In Ghana, approximately 4482 women are diagnosed with these diseases at advanced stages. Unfortunately, the early detection rate for these cancers is low compared to other women’s health services. This situation underscores the need to identify the locations of reproductive-age women who have not been screened for these cancers, to implement targeted public health interventions. This study aims to pinpoint these women’s locations for tailored interventions. Method: Bivariate analysis assessed the relationship between the independent and outcome variables. Hot spot analysis and Kriging Ordinary interpolation were employed to pinpoint the locations of these women. Results: Breast cancer examination and cervical cancer test rates were low, with a strong association between the two screening services. Several significant variables were identified: place of residence (p Conclusion: Low participation in these screening services was related to women’s age and the outreach efforts of fieldworkers. Breast and cervical cancer screenings are interconnected and could be combined to improve attendance rates. The Community-based Health Planning and Services (CHPS) implementation strategy could be cost-effective for screening women through targeted interventions, especially in identified clusters.
文摘针对燃气-蒸汽联合循环且余热锅炉不补燃的热电联产机组(combined power and heat unit,CHP),首先,基于能量守恒建立天然气流量与电力电压、电流的等值关系,进而考虑功率进行变换的物理特性,构建CHP的气电变换等效电路;考虑功率进行传递、释放的物理特性,构建CHP的气热转换、烟气排放及运行热损失方程;据此,确立CHP的物理特性等值模型,并定义该模型“以热定电”和“以电定热”策略下的控制参量。其次,利用牛顿法和管网水力计算基本原理,推导电潮流和气、热能流的修正方程及其雅可比元素表达式,提出计及CHP固有特性参数随系统运行状态变化的气-电-热混合能流统一分析方法。最后,通过具有不同CHP控制策略的气-电-热混合系统,验证所提方法的有效性及可行性。
文摘The present paper analyses a case study of the application of dynamic energy simulation on the energy efficiency improvement process of an existing commercial building,the retrofit of a CHP machine for the combined generation of heat and power is analysed.Great attention is dedicated to the correct sizing of the CHP/CCHP plant both in term of energy efficiency and economic viability.A detailed building model is developed and used,through dynamic building simulation,to identify the potential energy and economic savings achievable with the installation of a CHP/CCHP sized based on the results of the simulation itself.The work proves the usefulness of dynamic energy simulation as an evaluation tool for retrofits of CHP plants and provides suggestions on the correct sizing of CHP equipment.It is also meant to prove what could be achieved if those kinds of analysis were carried out during the design of the building.