This work proposed a LSTM(long short-term memory)model based on the double attention mechanism for power load prediction,to further improve the energy-saving potential and accurately control the distribution of power ...This work proposed a LSTM(long short-term memory)model based on the double attention mechanism for power load prediction,to further improve the energy-saving potential and accurately control the distribution of power load into each department of the hospital.Firstly,the key influencing factors of the power loads were screened based on the grey relational degree analysis.Secondly,in view of the characteristics of the power loads affected by various factors and time series changes,the feature attention mechanism and sequential attention mechanism were introduced on the basis of LSTM network.The former was used to analyze the relationship between the historical information and input variables autonomously to extract important features,and the latter was used to select the historical information at critical moments of LSTM network to improve the stability of long-term prediction effects.In the end,the experimental results from the power loads of Shanxi Eye Hospital show that the LSTM model based on the double attention mechanism has the higher forecasting accuracy and stability than the conventional LSTM,CNN-LSTM and attention-LSTM models.展开更多
On the occasion of the 80th anniversary of Nanjing Hydraulic Research Institute （NHRI） in 2015, NHRI would like to express its cordial gratitude and high respect to leaders at all levels, domestic and overseas alumn...On the occasion of the 80th anniversary of Nanjing Hydraulic Research Institute （NHRI） in 2015, NHRI would like to express its cordial gratitude and high respect to leaders at all levels, domestic and overseas alumni and people from all walks of life who have shown concem for and provided support to the construction and development of NHRI over the long term.展开更多
On the occasion of the 80^th anniversary of Nanjing Hydraulic Research Institute（NHRI）in 2015,NHRI would like to express its cordial gratitude and high respect to leaders at all levels,domestic and overseas alumni a...On the occasion of the 80^th anniversary of Nanjing Hydraulic Research Institute（NHRI）in 2015,NHRI would like to express its cordial gratitude and high respect to leaders at all levels,domestic and overseas alumni and people from all walks of life who have shown concern for and provided support to the construction and development of NHRI over the long term.展开更多
The integration of phase change material(PCM)with building-integrated photovoltaic(BIPV)presents a compelling approach to enhance solar energy utilization and mitigate indoor thermal loads,contributing to energy-effic...The integration of phase change material(PCM)with building-integrated photovoltaic(BIPV)presents a compelling approach to enhance solar energy utilization and mitigate indoor thermal loads,contributing to energy-efficient and low-carbon building development.Traditional BIPV-PCM structures,however,struggle to balance PV efficiency and thermal insulation,particularly with varying PCM wall positions.To address this situation,this study introduces a novel double-PCM BIPV composite envelope(BIPV-dPCM).An experimentally validated dynamic heat transfer model was developed and used to perform a comparative simulation analysis with three reference systems to quantify the energy-saving potential of the BIPV-dPCM,focusing on PV output and wall insulation effectiveness metrics.Further dimensionless parametric analysis were carried out to investigate the systematic performance of the two PCMs at different relativities.In addition,the coupled working mechanism of the BIPV-dPCM system concerning the power generation performance and thermal insulation performance under transient variations is explored.It was found that the BIPV-dPCM showcases superior thermoelectric coupling performance compared to three alternative enclosures.Incorporating two PCMs significantly enhances electrical exergy efficiency by 11.66%and thermal exergy efficiency by 1.54%,surpassing other reference systems.The increase in PCM latent heat ratio has a limited effect on performance gain.Notably,as the PCM thickness ratio exceeds 1,the decline in P value decelerates,for every 0.5 increment in the g,the P value diminishes by merely 0.2%.The ideal h is identified between 1 and 1.5,with 1.5 being optimal for energy conservation objectives.Additionally,the self-sufficiency coefficient(SSC)of the BIPV-dPCM remains robust,sustaining a range of 55%to 65%over prolonged periods.This study offers novel perspectives and serves as a design reference for optimizing building energy systems and enhancing cooling efficiencies in subtropical climates.展开更多
In nature, the most possible reason that helix is chosen as the basic structure of life molecule is based on its simplest chiral three-dimensional structure. The process of the conversion from chemical molecules to do...In nature, the most possible reason that helix is chosen as the basic structure of life molecule is based on its simplest chiral three-dimensional structure. The process of the conversion from chemical molecules to double helical molecules is completed by the topology effect which belongs to the simplest way to form helix, and no external power is needed;moreover, the energy of double helix has fixed drive direction [1]. The dual-branch loop helix (II)—the transition state of double helix has many uses, for example, it can be turned to double helix, and it may be broken into two fragments of a and b which can construct more complicated structures. So the dual- branch loop helix (II) can provide special "building block" of assembling biomembrane and other life molecules.展开更多
In the United States, university buildings use 17% of total non-residential building energy per year. According to the NREL （National Renewable Energy Laboratory）, the average lifecycle of a building in a university...In the United States, university buildings use 17% of total non-residential building energy per year. According to the NREL （National Renewable Energy Laboratory）, the average lifecycle of a building in a university is 42 years with an EUI （energy use intensity） of 23 kWh/m^2/y. Current building and energy codes limit the EUI to 16 kWh/m^2/y for new school buildings; this benchmark can vary depending on climate, occupancy, and other contextual factors. Although the LEED （leadership in energy and environmental design） system provides a set of guidelines to rate sustainable buildings, studies have shown that 28%-35% of the educational LEED-rated buildings use more energy than their conventional counterparts. This paper examines the issues specific to a LEED-rated design addition to an existing university building. The forum, a lecture hall expansion of to an existing building at the University of Kansas, has been proposed as environmentally friendly and energy-efficient building addition. Comfort and health aspects have been considered in the design in order to obtain LEED platinum certificate. The forum＇s energy performance strategies include a double-skin facade to reduce energy consumption and PV （photovoltaic） panels to generate onsite energy. This study considers various scenarios to meet NZEB （net-zero energy building） criteria and maximize energy savings. The feasibility of NZE criteria is evaluated for： （a） seasonal comparison; （b） facility occupancy; （c） PV panels＇ addition in relation to double skin facade. The results of NZEB approach are compared to LEED platinum requirements, based on Rol （return on investment） and PV panel＇s efficiency for this specific educational building.展开更多
The glass curtain wall is widely favored by the owners for its good appearance modeling efthct. In using process, however, excessive energy consumption, low level indoor eomtort and other problems of glass curtain wal...The glass curtain wall is widely favored by the owners for its good appearance modeling efthct. In using process, however, excessive energy consumption, low level indoor eomtort and other problems of glass curtain wall are often exposed. Aiming at office buildings in hot Summer and cold Winter zone, taking the optimization of thermal comfort of double glass curtain wall in the summer and the reduetion of building energy consumption throughout the year as the breakthrough point, using the method of energy simulation analysis, through changing the size of internal shading component in the simulated room, this paper analyzes and summarizes the variation law of its energy consumption value, to explore the relatively reasonable design plan of shading systems of the building with glass curtain wall.展开更多
As a symbol of green architecture,double skin facade(DSF)represents a design which possesses many energy saving features,but due to the complexity of the system,the real performances and benefits have been difficult t...As a symbol of green architecture,double skin facade(DSF)represents a design which possesses many energy saving features,but due to the complexity of the system,the real performances and benefits have been difficult to predict.The objective of this study was to inform the applicability of DSFs,and contribute to the positive impacts of DSF designs.This study compared and contrasted energy savings in a temperate climate,where heating was the dominant energy strategy,and in a subtropical climate,where cooling spaces was the dominant issue.This paper focused on a university office building with a west facing shaft box window facade.The research method was a paired analysis of simulation studies which compared the energy performance of a set of buildings in two different climates.Simulation results showed a good agreement with measurements undertaken in the exiting building during a two-week period.The results specified that DSFs are capable of almost 50%energy savings in temperate and 16%in subtropical climates.Although these indicated DSFs are more suitable for temperate climates than warmer regions,the amount of energy savings in subtropical climates were also considerable.However,due to the costs of DSFs and potential loss of leasable floor area,investigations into other feasible ventilation options are necessary before final building design decisions are made.展开更多
基金Supported by the Shaanxi Provincial Education Department 2022 Key Research Program Project(22JS022)the National Natural Science Foundation of China(51808428)
文摘This work proposed a LSTM(long short-term memory)model based on the double attention mechanism for power load prediction,to further improve the energy-saving potential and accurately control the distribution of power load into each department of the hospital.Firstly,the key influencing factors of the power loads were screened based on the grey relational degree analysis.Secondly,in view of the characteristics of the power loads affected by various factors and time series changes,the feature attention mechanism and sequential attention mechanism were introduced on the basis of LSTM network.The former was used to analyze the relationship between the historical information and input variables autonomously to extract important features,and the latter was used to select the historical information at critical moments of LSTM network to improve the stability of long-term prediction effects.In the end,the experimental results from the power loads of Shanxi Eye Hospital show that the LSTM model based on the double attention mechanism has the higher forecasting accuracy and stability than the conventional LSTM,CNN-LSTM and attention-LSTM models.
文摘On the occasion of the 80th anniversary of Nanjing Hydraulic Research Institute （NHRI） in 2015, NHRI would like to express its cordial gratitude and high respect to leaders at all levels, domestic and overseas alumni and people from all walks of life who have shown concem for and provided support to the construction and development of NHRI over the long term.
文摘On the occasion of the 80^th anniversary of Nanjing Hydraulic Research Institute（NHRI）in 2015,NHRI would like to express its cordial gratitude and high respect to leaders at all levels,domestic and overseas alumni and people from all walks of life who have shown concern for and provided support to the construction and development of NHRI over the long term.
基金supported by the Guangdong Basic and Applied Basic Research Foundation(Grant No.2023A1515010681)Fundamental Research Funds for the Central Universities(Grant No.21622417)Special Projects in Key Fields of Guangdong Universities(2022ZDZX1005).
文摘The integration of phase change material(PCM)with building-integrated photovoltaic(BIPV)presents a compelling approach to enhance solar energy utilization and mitigate indoor thermal loads,contributing to energy-efficient and low-carbon building development.Traditional BIPV-PCM structures,however,struggle to balance PV efficiency and thermal insulation,particularly with varying PCM wall positions.To address this situation,this study introduces a novel double-PCM BIPV composite envelope(BIPV-dPCM).An experimentally validated dynamic heat transfer model was developed and used to perform a comparative simulation analysis with three reference systems to quantify the energy-saving potential of the BIPV-dPCM,focusing on PV output and wall insulation effectiveness metrics.Further dimensionless parametric analysis were carried out to investigate the systematic performance of the two PCMs at different relativities.In addition,the coupled working mechanism of the BIPV-dPCM system concerning the power generation performance and thermal insulation performance under transient variations is explored.It was found that the BIPV-dPCM showcases superior thermoelectric coupling performance compared to three alternative enclosures.Incorporating two PCMs significantly enhances electrical exergy efficiency by 11.66%and thermal exergy efficiency by 1.54%,surpassing other reference systems.The increase in PCM latent heat ratio has a limited effect on performance gain.Notably,as the PCM thickness ratio exceeds 1,the decline in P value decelerates,for every 0.5 increment in the g,the P value diminishes by merely 0.2%.The ideal h is identified between 1 and 1.5,with 1.5 being optimal for energy conservation objectives.Additionally,the self-sufficiency coefficient(SSC)of the BIPV-dPCM remains robust,sustaining a range of 55%to 65%over prolonged periods.This study offers novel perspectives and serves as a design reference for optimizing building energy systems and enhancing cooling efficiencies in subtropical climates.
文摘In nature, the most possible reason that helix is chosen as the basic structure of life molecule is based on its simplest chiral three-dimensional structure. The process of the conversion from chemical molecules to double helical molecules is completed by the topology effect which belongs to the simplest way to form helix, and no external power is needed;moreover, the energy of double helix has fixed drive direction [1]. The dual-branch loop helix (II)—the transition state of double helix has many uses, for example, it can be turned to double helix, and it may be broken into two fragments of a and b which can construct more complicated structures. So the dual- branch loop helix (II) can provide special "building block" of assembling biomembrane and other life molecules.
文摘In the United States, university buildings use 17% of total non-residential building energy per year. According to the NREL （National Renewable Energy Laboratory）, the average lifecycle of a building in a university is 42 years with an EUI （energy use intensity） of 23 kWh/m^2/y. Current building and energy codes limit the EUI to 16 kWh/m^2/y for new school buildings; this benchmark can vary depending on climate, occupancy, and other contextual factors. Although the LEED （leadership in energy and environmental design） system provides a set of guidelines to rate sustainable buildings, studies have shown that 28%-35% of the educational LEED-rated buildings use more energy than their conventional counterparts. This paper examines the issues specific to a LEED-rated design addition to an existing university building. The forum, a lecture hall expansion of to an existing building at the University of Kansas, has been proposed as environmentally friendly and energy-efficient building addition. Comfort and health aspects have been considered in the design in order to obtain LEED platinum certificate. The forum＇s energy performance strategies include a double-skin facade to reduce energy consumption and PV （photovoltaic） panels to generate onsite energy. This study considers various scenarios to meet NZEB （net-zero energy building） criteria and maximize energy savings. The feasibility of NZE criteria is evaluated for： （a） seasonal comparison; （b） facility occupancy; （c） PV panels＇ addition in relation to double skin facade. The results of NZEB approach are compared to LEED platinum requirements, based on Rol （return on investment） and PV panel＇s efficiency for this specific educational building.
文摘The glass curtain wall is widely favored by the owners for its good appearance modeling efthct. In using process, however, excessive energy consumption, low level indoor eomtort and other problems of glass curtain wall are often exposed. Aiming at office buildings in hot Summer and cold Winter zone, taking the optimization of thermal comfort of double glass curtain wall in the summer and the reduetion of building energy consumption throughout the year as the breakthrough point, using the method of energy simulation analysis, through changing the size of internal shading component in the simulated room, this paper analyzes and summarizes the variation law of its energy consumption value, to explore the relatively reasonable design plan of shading systems of the building with glass curtain wall.
文摘As a symbol of green architecture,double skin facade(DSF)represents a design which possesses many energy saving features,but due to the complexity of the system,the real performances and benefits have been difficult to predict.The objective of this study was to inform the applicability of DSFs,and contribute to the positive impacts of DSF designs.This study compared and contrasted energy savings in a temperate climate,where heating was the dominant energy strategy,and in a subtropical climate,where cooling spaces was the dominant issue.This paper focused on a university office building with a west facing shaft box window facade.The research method was a paired analysis of simulation studies which compared the energy performance of a set of buildings in two different climates.Simulation results showed a good agreement with measurements undertaken in the exiting building during a two-week period.The results specified that DSFs are capable of almost 50%energy savings in temperate and 16%in subtropical climates.Although these indicated DSFs are more suitable for temperate climates than warmer regions,the amount of energy savings in subtropical climates were also considerable.However,due to the costs of DSFs and potential loss of leasable floor area,investigations into other feasible ventilation options are necessary before final building design decisions are made.
