A plot experiment including four treatments, CK (N 105 kg ha-1 as urea, including a basal N application of 35 kg ha-I and a topdressing N 70 kg ha-1 at turned green stage) and optimized N management (OPT1, OPT2 and...A plot experiment including four treatments, CK (N 105 kg ha-1 as urea, including a basal N application of 35 kg ha-I and a topdressing N 70 kg ha-1 at turned green stage) and optimized N management (OPT1, OPT2 and OPT3, applied two-thirds, one-third and two-fifths N at jointing stage, respectively, total N 60 kg ha-l), was conducted to evaluate the effects of nitrogen management on growth and N uptake of winter wheat (Triticum aestivum), Dongnong 1, which is the first highly cold tolerant winter wheat in China. Index of population quality, N uptake and yield were determined. The ear-bearing tiller rate was increased by above 12%, and the leaf area index, biomass and N uptake were significantly decreased (P〈O.05) at jointing stage. OPT treatments increased the grain to leaf area ratio at heading stage, the dry matter weight and N uptake after heading by 14.3-27.9%, 11.6-28.7% and 118.1-161.8 %, respectively. The yield of the OPT treatments was increased by 14.2-37.5% compared with CK, and there was a significant difference (P〈0.05) between CK and OPT1 treatments. Harvest index and N partial factor productivity (PFP, kg grain yield per kg N applied) was clearly enhanced from 0.4 and 35.6 kg, respectively for CK to an average of 0.48 (P〈0.05) and 77.6 kg (P〈0.05) in the OPT treatments. These results indicated that the optimized N management increased the harvest index, yield and N use efficiency by decreasing the N application rate and postponing N application time, improved wheat population quality, controlled excessive growth in the vegetative stages and increased dry matter and N accumulation rates after heading.展开更多
The effects of yield increase and mechanism of site-specific nitrogen management (SSNM) in five rice varieties from cold areas of northeastern China were studied. Plot experiment for critical SPAD value and experime...The effects of yield increase and mechanism of site-specific nitrogen management (SSNM) in five rice varieties from cold areas of northeastern China were studied. Plot experiment for critical SPAD value and experiments of two fertilization methods, SSNM and farmer's fertilization practice (FFP) were conducted to study their effects on the quality and dry matter accumulation of rice population, as well as N uptake. Compared with FFP, SSNM significantly decreased the average N rate by 33.8%, significantly increased average ear-bearing tiller rate and LAI for grain-filling stage by 12.3% and 14.1-27.6%, correspondingly, improved dry matter weight and N uptake after heading period by 4.3-29.1% and 11.8-55.1% (P 〈 0.05), and heightened recovery efficiency and agronomic efficiency by 38.5-133.4% (P 〈 0.05) and 39.8-194.3% (P 〈 0.05), respectively, as well as increased the average yield by 9.8% in 2004 and 2005. The results indicated that the accumulation rate of dry matter and N increased the rice yield and N use efficiency, because of improving rice population quality and increasing LAI after heading period.展开更多
Because of the overbearing low temperature,cold areas increase the morbidity and mortality of chronic non-communicable diseases(chronic diseases)in exposed populations.With the growth of the aging population and the s...Because of the overbearing low temperature,cold areas increase the morbidity and mortality of chronic non-communicable diseases(chronic diseases)in exposed populations.With the growth of the aging population and the superposition of lifestyle risk factors,the number of people with chronic diseases in cold areas is climbing,and the family and social burdens are rising.These health-threatening circumstances in the cold areas render the general practitioners to face serious challenges and difficulties in the community management of chronic diseases.This paper summarizes the current situation of chronic disease management in cold areas and explores the relevant management models so as to provide a useful reference for regional health construction,graded diagnosis and treatment,and prevention and control of chronic diseases in China.展开更多
Five rice varieties were planted to determine the variation of the yield and quality traits in five different regions in a cold area of China. The results showed that the number of the panicles, the number of grains p...Five rice varieties were planted to determine the variation of the yield and quality traits in five different regions in a cold area of China. The results showed that the number of the panicles, the number of grains per panicle and percentage of head-milled rice displayed quadratic curves against the accumulated temperature, and the sterile rate decreased with greater accumulated temperature. However, 1 000-grain weight had no correlation with the accumulated temperature and protein content, amylose content and taste also had no obvious relation with the accumulated temperature. The results from the accumulated temperature differed with rice variety, so the temperature insensitive type variety should be proposed for production.展开更多
Log house is a traditional type of vernacular dwelling in Chinese cold area. It contains distinct regional characteristics and architectural cultures. In recent years,log house has come into vogue softly with the deve...Log house is a traditional type of vernacular dwelling in Chinese cold area. It contains distinct regional characteristics and architectural cultures. In recent years,log house has come into vogue softly with the development of wood techniques. However,log houses expend too much wood materials. There are also many negative aspects of this type of wood building which go against the criteria of energy conservation,and its high prime cost hinders the application as well. To solve these problems, the paper emphasizes using more environmental standardized techniques which save cost at the same time,and put forward technical strategy to improve the log walls. The optimization schemes are mainly divided into two categories: internal insulation and filled insulation. Each type of insulation is respectively derived two schemes through changing the thickness of main structure layers and insulation layer. Firstly,we use Weto software to calculate the timber volume of the four schemes,and it concludes that all the optimizations can save more timber than the prototype log wall with the section of 200 mm × 200 mm. Secondly,thermal comfort of each scheme is insulated in Design Builder.The results show that thermal insulation of filling type represents better than the other schemes. At last,we use thermal calculating formula to calculate thermal resistance of every scheme. Contrast to the energy efficiency standards of Heilongjiang Province, the data show that the four schemes meet the requirements of the specification.展开更多
The management of chronic kidney disease(CKD)patients in cold areas is an important task in the daily practice of primary medical and health institutions.An important way to reduce the burden of CKD is to achieve earl...The management of chronic kidney disease(CKD)patients in cold areas is an important task in the daily practice of primary medical and health institutions.An important way to reduce the burden of CKD is to achieve early identification of and implement timely intervention on the relevant risk factors.Studies have shown that diet,alcohol,tobacco,air,sedentary and other factors in cold areas have negative impacts on human kidneys;yet,our current understanding of the effect of cold stimulation on CKD remains blurry.This paper introduces the research progress of risk factors related to CKD in cold areas and analytically summarizes the pathogenesis of CKD caused by cold stimulation,aiming to provide a reference work for the prevention,screening,evaluation,and management of CKD in cold areas.展开更多
While osteoporosis is a chronic disease caused by multiple factors,it is also a risk factor for fractures.At present,numerous risk factors for osteoporosis and secondary fractures have been identified,including sunlig...While osteoporosis is a chronic disease caused by multiple factors,it is also a risk factor for fractures.At present,numerous risk factors for osteoporosis and secondary fractures have been identified,including sunlight,physical fitness,gender,age,trauma,dietary habits,tobacco,alcohol,drugs,air quality,and genetics.Despite that factors such as long winters,short daylight hours,less daily physical activity,air pollution,low calcium and high salt diet,and sedentary lifestyle could negatively impact the bones of residents in the alpine regions of northern China,the direct effect of low-temperature stimulation on bone growth and development remains unclear.In this study,by reviewing current research progress related to osteoporosis and fracture risk in northern China,we proposed appropriate preventive measures for different risk factors to reduce the occurrence of osteoporosis and fracture in cold areas of northern China.展开更多
This article take cold regions of nlral residential building envelope as the research object, suitability technical theory as the theoretical basis, we evaluation of rural residential energy envelope because China's ...This article take cold regions of nlral residential building envelope as the research object, suitability technical theory as the theoretical basis, we evaluation of rural residential energy envelope because China's rural areas is chmacterized by large regional differences and to find a solution for the envelope. It could be considered as the useful reference for retrofit design of similar projects.展开更多
The winter in the severe cold area of China is long and cold. The mean outdoor temperature is about-10. 0 ℃ during the winter in Harbin,while the indoor air temperature is often above24 ℃. How does the indoor enviro...The winter in the severe cold area of China is long and cold. The mean outdoor temperature is about-10. 0 ℃ during the winter in Harbin,while the indoor air temperature is often above24 ℃. How does the indoor environment influence human thermal comfort and adaptation in such an overheated environment?A combined approach of spot-reading measurements and occupant interview s w as adopted in nine residential buildings of five communities during the heating period in 2013-2014. Tw enty residents w ere chosen as respondents. Totally 308 valid questionnaires w ere collected. The heating periods w ere separated into three phases based on the outdoor temperature.The results show that the mean indoor air temperatures in theearly-,mid-and late-heating periods w ere 23. 6 ℃,24. 3 ℃and 25. 0 ℃,respectively,w hich w ere larger than or close to the upper limit recommended by thermal comfort standards, and slightly higher than the related thermal neutral temperatures. With the heating process,the mean clothing insulation of residents decreased. Opening w indow s and reducing clothing w ere mainly taken by the residents to adapt to the overheated environment.The thermal neutral temperature has an upw ard tendency w ith the increasing indoor air temperature. On the other hand,overheating in residential buildings w ould make residents open w indow s,w hich may cause thermal discomfort and energy w aste. Therefore,the low er limit of the comfort indoor air temperature range should be suggested as the heating temperature,w hich could fully arouse residents' adaptation and achieve sustainable building designs.展开更多
Occupancy is used to represent the movements and locations of users among various zones of buildings,and it is the basis of all other daily energy consumption behaviors.This study investigated eight families in cold a...Occupancy is used to represent the movements and locations of users among various zones of buildings,and it is the basis of all other daily energy consumption behaviors.This study investigated eight families in cold areas of China based on occupancy measurements obtained in four main rooms,i.e.,living room,bedroom,kitchen,and bathroom.In particular,we analyzed the duration of user occupancy and hourly mean occupancy,and characterized their regular and random features.According to the results,we developed an event-based occupancy model using an inhomogeneous Markov chain,where the rooms were modeled and daily events were divided into three categories according to their randomness.We established a new method for conversion between event characteristic parameters and a transition probability matrix,as well as an overlap avoidance method for active events.The model was then validated using real data.The results showed that the model performed well in terms of two evaluation criteria.The model should improve the accuracy of simulations of occupancy.展开更多
With the continuous development of domestic highway construction,highway civil engineering and service level quality have attracted much attention.Good pavement quality and high-quality service make people feel comfor...With the continuous development of domestic highway construction,highway civil engineering and service level quality have attracted much attention.Good pavement quality and high-quality service make people feel comfortable and smooth when traveling.High-quality pavement can significantly reduce the probability of traffic accidents.At present,there is a direct relationship between pavement quality and pavement construction operations.Carrying out pavement construction operations in cold high-altitude areas requires a reasonable selection of construction equipment and methods.The application of warm-mix asphalt pavement construction technology can ensure pavement quality.Therefore,this paper analyzes the advantages of warm-mix technology,the environmental characteristics of cold high-altitude areas,and construction preparations,and discusses the construction technology of warm-mix asphalt pavement in cold high-altitude areas in detail,to improve the overall road quality of cold high-altitude areas.展开更多
Climate is one of the environmental conditions on which people live.Climate conditions impact every aspect of people's daily life and production activities,even the survival of humankind.In recent years,human acti...Climate is one of the environmental conditions on which people live.Climate conditions impact every aspect of people's daily life and production activities,even the survival of humankind.In recent years,human activities have adversely changed the climate.The emergence of global warming and extreme weather has prompted people to pay attention to the impact of climate on life.The adverse climate issues include reduced quality of air and food,facilitated spread of diseases and increased mortality of the population.Being more orientated to climate changes in the past,research has been less alerted to the negative impacts that climate changes could bring to human health.This could be ascribed to that after living in a region for a long time,the human body has"adapted"to climate.And after adaptation,routine health outcomes such as disease incidence and hospitalization rate become less obvious,making the habitants blind from the undesirable impacts of climate on the health status.This review article summarizes the impacts of cold climate on human development,including maternal/fetal factors,lifestyle factors,etc.,and delineates the relationship between cold climate and human health.展开更多
China's infrastructure has gradually achieved large-scale development,and transportation construction has also shifted from east to west,transitioning from plains to mountainous areas.High-fill embankments of diff...China's infrastructure has gradually achieved large-scale development,and transportation construction has also shifted from east to west,transitioning from plains to mountainous areas.High-fill embankments of different sizes in mountainous areas are unavoidable,and the settlement of high-fill embankments is usually the most concerned issue in high-fill projects.According to the current research of highway projects,most of the high embankments in mountainous areas are soil-rock mixed embankments or rock-filled embankments,and their post-construction settlements are directly related to construction technology and the type of filler used.In this paper,the problems in the settlement control of earth-filled embankment and related factors are analyzed in detail.The settlement control technology of high-fill embankment in high-cold and high-altitude areas is also discussed,so as to ensure the overall quality of high-fill embankment.展开更多
In spline rolling process, the contact area between roller and workpiece plays an important role in calculating rolling-force and rolling-moment. For the purpose of studying the contact area, contact state between rol...In spline rolling process, the contact area between roller and workpiece plays an important role in calculating rolling-force and rolling-moment. For the purpose of studying the contact area, contact state between roller and workpiece in process of spline cold rolling based upon cross rolling is analyzed. According to the suitable hypothesis, the mathematic model of roller-tooth-curve in optional position of rolling process is established. Combing the theory of conjugate curves with the theory of envelope curve, the corresponding mathematic model of workpiece-tooth-curve is established. By utilizing establishing mathematic models, the algorithm of entire contact area in rolling process is created. On the basis of the algorithm, calculation-program is compiled under MATLAB program language environment. The calculation-program actualizes quantitative analysis and quantitative calculation of contact areas. Utilizing the calculation-program, the influence of parameters on contact area is analyzed, and the tendency is consistent with the manufacturing experience. In consideration of rolling-force optimization, the primary process parameters may be selected according to results of calculation. The result of the present study may provide basis for research on rolling-force and rolling-moment.展开更多
To improve the comfortable physical environment for square in severe cold regions' rural areas. This paper applies the methods of questionnaires,field testing and statistical analysis to compare and analyze two di...To improve the comfortable physical environment for square in severe cold regions' rural areas. This paper applies the methods of questionnaires,field testing and statistical analysis to compare and analyze two different square cases of Qingyunpu in Liaoning Province,and conclude the main factors which affect the physical environmental comfort. The improvement strategies for physical environment of rural square are put forward from the aspects of site selection,road position,orientation,landscape design,and ground pavement material selection,aiming to provide the design basis for the physical environment of square in severe cold regions' rural areas.展开更多
Carbon sequestration and emission reduction in the construction industry plays an important role in China’s goal of achieving carbon neutrality.Research in Zhuzhou city scored 42 since the assessment of the green bui...Carbon sequestration and emission reduction in the construction industry plays an important role in China’s goal of achieving carbon neutrality.Research in Zhuzhou city scored 42 since the assessment of the green building project situation as the research object,in hot summer and cold winter areas of analysis and evaluation on the development of green building technology,and then sums up the carbon neutral background the priority areas and tasks for the development of green building techniques,optimization of the construction industry into a new era under the background of green development to provide the reference.展开更多
基金supported by grants from the National Basic Research Program of China (973 Program,2009CB118606)Special Fund for Agro-Scientific Research in the Public Interest, China (201103003)
文摘A plot experiment including four treatments, CK (N 105 kg ha-1 as urea, including a basal N application of 35 kg ha-I and a topdressing N 70 kg ha-1 at turned green stage) and optimized N management (OPT1, OPT2 and OPT3, applied two-thirds, one-third and two-fifths N at jointing stage, respectively, total N 60 kg ha-l), was conducted to evaluate the effects of nitrogen management on growth and N uptake of winter wheat (Triticum aestivum), Dongnong 1, which is the first highly cold tolerant winter wheat in China. Index of population quality, N uptake and yield were determined. The ear-bearing tiller rate was increased by above 12%, and the leaf area index, biomass and N uptake were significantly decreased (P〈O.05) at jointing stage. OPT treatments increased the grain to leaf area ratio at heading stage, the dry matter weight and N uptake after heading by 14.3-27.9%, 11.6-28.7% and 118.1-161.8 %, respectively. The yield of the OPT treatments was increased by 14.2-37.5% compared with CK, and there was a significant difference (P〈0.05) between CK and OPT1 treatments. Harvest index and N partial factor productivity (PFP, kg grain yield per kg N applied) was clearly enhanced from 0.4 and 35.6 kg, respectively for CK to an average of 0.48 (P〈0.05) and 77.6 kg (P〈0.05) in the OPT treatments. These results indicated that the optimized N management increased the harvest index, yield and N use efficiency by decreasing the N application rate and postponing N application time, improved wheat population quality, controlled excessive growth in the vegetative stages and increased dry matter and N accumulation rates after heading.
文摘The effects of yield increase and mechanism of site-specific nitrogen management (SSNM) in five rice varieties from cold areas of northeastern China were studied. Plot experiment for critical SPAD value and experiments of two fertilization methods, SSNM and farmer's fertilization practice (FFP) were conducted to study their effects on the quality and dry matter accumulation of rice population, as well as N uptake. Compared with FFP, SSNM significantly decreased the average N rate by 33.8%, significantly increased average ear-bearing tiller rate and LAI for grain-filling stage by 12.3% and 14.1-27.6%, correspondingly, improved dry matter weight and N uptake after heading period by 4.3-29.1% and 11.8-55.1% (P 〈 0.05), and heightened recovery efficiency and agronomic efficiency by 38.5-133.4% (P 〈 0.05) and 39.8-194.3% (P 〈 0.05), respectively, as well as increased the average yield by 9.8% in 2004 and 2005. The results indicated that the accumulation rate of dry matter and N increased the rice yield and N use efficiency, because of improving rice population quality and increasing LAI after heading period.
基金supported by the National Natural Science Foundation of China(72074065),Cultivation Fund for Key Scientific Research Projects of Harbin Medical University,and Harbin Applied Technology and Development Project(2017RAXXJ052).
文摘Because of the overbearing low temperature,cold areas increase the morbidity and mortality of chronic non-communicable diseases(chronic diseases)in exposed populations.With the growth of the aging population and the superposition of lifestyle risk factors,the number of people with chronic diseases in cold areas is climbing,and the family and social burdens are rising.These health-threatening circumstances in the cold areas render the general practitioners to face serious challenges and difficulties in the community management of chronic diseases.This paper summarizes the current situation of chronic disease management in cold areas and explores the relevant management models so as to provide a useful reference for regional health construction,graded diagnosis and treatment,and prevention and control of chronic diseases in China.
基金Supported by the Public Industry Project of Ministry of Agriculture(201303126)Postdoctoral Fund of Heilongjiang Province(LBH-Z13189)Innovation Project of Institute(2012ZD013)
文摘Five rice varieties were planted to determine the variation of the yield and quality traits in five different regions in a cold area of China. The results showed that the number of the panicles, the number of grains per panicle and percentage of head-milled rice displayed quadratic curves against the accumulated temperature, and the sterile rate decreased with greater accumulated temperature. However, 1 000-grain weight had no correlation with the accumulated temperature and protein content, amylose content and taste also had no obvious relation with the accumulated temperature. The results from the accumulated temperature differed with rice variety, so the temperature insensitive type variety should be proposed for production.
基金Sponsored by the National Natural Science Foundation of China(Grant No.51478137)the Sub Task of Science and Technology Support Program in China(Grant No.2012BAJ06B04-02)
文摘Log house is a traditional type of vernacular dwelling in Chinese cold area. It contains distinct regional characteristics and architectural cultures. In recent years,log house has come into vogue softly with the development of wood techniques. However,log houses expend too much wood materials. There are also many negative aspects of this type of wood building which go against the criteria of energy conservation,and its high prime cost hinders the application as well. To solve these problems, the paper emphasizes using more environmental standardized techniques which save cost at the same time,and put forward technical strategy to improve the log walls. The optimization schemes are mainly divided into two categories: internal insulation and filled insulation. Each type of insulation is respectively derived two schemes through changing the thickness of main structure layers and insulation layer. Firstly,we use Weto software to calculate the timber volume of the four schemes,and it concludes that all the optimizations can save more timber than the prototype log wall with the section of 200 mm × 200 mm. Secondly,thermal comfort of each scheme is insulated in Design Builder.The results show that thermal insulation of filling type represents better than the other schemes. At last,we use thermal calculating formula to calculate thermal resistance of every scheme. Contrast to the energy efficiency standards of Heilongjiang Province, the data show that the four schemes meet the requirements of the specification.
基金supported by the Natural Science Foundation of China(72074065)supported by the Key Project of Harbin Medical University Cultivation Fund.
文摘The management of chronic kidney disease(CKD)patients in cold areas is an important task in the daily practice of primary medical and health institutions.An important way to reduce the burden of CKD is to achieve early identification of and implement timely intervention on the relevant risk factors.Studies have shown that diet,alcohol,tobacco,air,sedentary and other factors in cold areas have negative impacts on human kidneys;yet,our current understanding of the effect of cold stimulation on CKD remains blurry.This paper introduces the research progress of risk factors related to CKD in cold areas and analytically summarizes the pathogenesis of CKD caused by cold stimulation,aiming to provide a reference work for the prevention,screening,evaluation,and management of CKD in cold areas.
基金the Natural Science Foundation of China(72074065)Cultivation Fund for Key Scientific Research Projects of Harbin Medical University,and funded by Harbin Applied Technique and Development Project(2017RAXXJ052).
文摘While osteoporosis is a chronic disease caused by multiple factors,it is also a risk factor for fractures.At present,numerous risk factors for osteoporosis and secondary fractures have been identified,including sunlight,physical fitness,gender,age,trauma,dietary habits,tobacco,alcohol,drugs,air quality,and genetics.Despite that factors such as long winters,short daylight hours,less daily physical activity,air pollution,low calcium and high salt diet,and sedentary lifestyle could negatively impact the bones of residents in the alpine regions of northern China,the direct effect of low-temperature stimulation on bone growth and development remains unclear.In this study,by reviewing current research progress related to osteoporosis and fracture risk in northern China,we proposed appropriate preventive measures for different risk factors to reduce the occurrence of osteoporosis and fracture in cold areas of northern China.
文摘This article take cold regions of nlral residential building envelope as the research object, suitability technical theory as the theoretical basis, we evaluation of rural residential energy envelope because China's rural areas is chmacterized by large regional differences and to find a solution for the envelope. It could be considered as the useful reference for retrofit design of similar projects.
文摘The winter in the severe cold area of China is long and cold. The mean outdoor temperature is about-10. 0 ℃ during the winter in Harbin,while the indoor air temperature is often above24 ℃. How does the indoor environment influence human thermal comfort and adaptation in such an overheated environment?A combined approach of spot-reading measurements and occupant interview s w as adopted in nine residential buildings of five communities during the heating period in 2013-2014. Tw enty residents w ere chosen as respondents. Totally 308 valid questionnaires w ere collected. The heating periods w ere separated into three phases based on the outdoor temperature.The results show that the mean indoor air temperatures in theearly-,mid-and late-heating periods w ere 23. 6 ℃,24. 3 ℃and 25. 0 ℃,respectively,w hich w ere larger than or close to the upper limit recommended by thermal comfort standards, and slightly higher than the related thermal neutral temperatures. With the heating process,the mean clothing insulation of residents decreased. Opening w indow s and reducing clothing w ere mainly taken by the residents to adapt to the overheated environment.The thermal neutral temperature has an upw ard tendency w ith the increasing indoor air temperature. On the other hand,overheating in residential buildings w ould make residents open w indow s,w hich may cause thermal discomfort and energy w aste. Therefore,the low er limit of the comfort indoor air temperature range should be suggested as the heating temperature,w hich could fully arouse residents' adaptation and achieve sustainable building designs.
基金the funding support from the National Natural Science Foundation of China(No.52008129)the Postdoctoral Science Foundation of China(No.2019M651289)the National Natural Science Foundation of Heilongjiang Province(No.LH2020E051,No.GZ20210211).
文摘Occupancy is used to represent the movements and locations of users among various zones of buildings,and it is the basis of all other daily energy consumption behaviors.This study investigated eight families in cold areas of China based on occupancy measurements obtained in four main rooms,i.e.,living room,bedroom,kitchen,and bathroom.In particular,we analyzed the duration of user occupancy and hourly mean occupancy,and characterized their regular and random features.According to the results,we developed an event-based occupancy model using an inhomogeneous Markov chain,where the rooms were modeled and daily events were divided into three categories according to their randomness.We established a new method for conversion between event characteristic parameters and a transition probability matrix,as well as an overlap avoidance method for active events.The model was then validated using real data.The results showed that the model performed well in terms of two evaluation criteria.The model should improve the accuracy of simulations of occupancy.
文摘With the continuous development of domestic highway construction,highway civil engineering and service level quality have attracted much attention.Good pavement quality and high-quality service make people feel comfortable and smooth when traveling.High-quality pavement can significantly reduce the probability of traffic accidents.At present,there is a direct relationship between pavement quality and pavement construction operations.Carrying out pavement construction operations in cold high-altitude areas requires a reasonable selection of construction equipment and methods.The application of warm-mix asphalt pavement construction technology can ensure pavement quality.Therefore,this paper analyzes the advantages of warm-mix technology,the environmental characteristics of cold high-altitude areas,and construction preparations,and discusses the construction technology of warm-mix asphalt pavement in cold high-altitude areas in detail,to improve the overall road quality of cold high-altitude areas.
文摘Climate is one of the environmental conditions on which people live.Climate conditions impact every aspect of people's daily life and production activities,even the survival of humankind.In recent years,human activities have adversely changed the climate.The emergence of global warming and extreme weather has prompted people to pay attention to the impact of climate on life.The adverse climate issues include reduced quality of air and food,facilitated spread of diseases and increased mortality of the population.Being more orientated to climate changes in the past,research has been less alerted to the negative impacts that climate changes could bring to human health.This could be ascribed to that after living in a region for a long time,the human body has"adapted"to climate.And after adaptation,routine health outcomes such as disease incidence and hospitalization rate become less obvious,making the habitants blind from the undesirable impacts of climate on the health status.This review article summarizes the impacts of cold climate on human development,including maternal/fetal factors,lifestyle factors,etc.,and delineates the relationship between cold climate and human health.
文摘China's infrastructure has gradually achieved large-scale development,and transportation construction has also shifted from east to west,transitioning from plains to mountainous areas.High-fill embankments of different sizes in mountainous areas are unavoidable,and the settlement of high-fill embankments is usually the most concerned issue in high-fill projects.According to the current research of highway projects,most of the high embankments in mountainous areas are soil-rock mixed embankments or rock-filled embankments,and their post-construction settlements are directly related to construction technology and the type of filler used.In this paper,the problems in the settlement control of earth-filled embankment and related factors are analyzed in detail.The settlement control technology of high-fill embankment in high-cold and high-altitude areas is also discussed,so as to ensure the overall quality of high-fill embankment.
基金supported by National Natural Science Foundation of China (No.50675145)Shanxi Province Key Project of Science and Technology of China (No.2006031147)+1 种基金Shanxi Province Innovation Project for Graduate Students of China (No.20061027)the Shanxi Province Key Project for Studied-abroad Returnee of China.
文摘In spline rolling process, the contact area between roller and workpiece plays an important role in calculating rolling-force and rolling-moment. For the purpose of studying the contact area, contact state between roller and workpiece in process of spline cold rolling based upon cross rolling is analyzed. According to the suitable hypothesis, the mathematic model of roller-tooth-curve in optional position of rolling process is established. Combing the theory of conjugate curves with the theory of envelope curve, the corresponding mathematic model of workpiece-tooth-curve is established. By utilizing establishing mathematic models, the algorithm of entire contact area in rolling process is created. On the basis of the algorithm, calculation-program is compiled under MATLAB program language environment. The calculation-program actualizes quantitative analysis and quantitative calculation of contact areas. Utilizing the calculation-program, the influence of parameters on contact area is analyzed, and the tendency is consistent with the manufacturing experience. In consideration of rolling-force optimization, the primary process parameters may be selected according to results of calculation. The result of the present study may provide basis for research on rolling-force and rolling-moment.
基金Sponsored by the National Project of Scientific and Technical Supporting Programs Funded by Ministry of Science & Technology of China (Grant No.2013BAJ12B02)the National Natural Science Foundation of Heilongjiang (Grant No.E201316)the Fundamental Research Funds for the Central Universities (Grant No.HIT.KISTP.201419)
文摘To improve the comfortable physical environment for square in severe cold regions' rural areas. This paper applies the methods of questionnaires,field testing and statistical analysis to compare and analyze two different square cases of Qingyunpu in Liaoning Province,and conclude the main factors which affect the physical environmental comfort. The improvement strategies for physical environment of rural square are put forward from the aspects of site selection,road position,orientation,landscape design,and ground pavement material selection,aiming to provide the design basis for the physical environment of square in severe cold regions' rural areas.
基金supported by the Hunan Provincial and Municipal Joint Fund(No.2022JJ50069).
文摘Carbon sequestration and emission reduction in the construction industry plays an important role in China’s goal of achieving carbon neutrality.Research in Zhuzhou city scored 42 since the assessment of the green building project situation as the research object,in hot summer and cold winter areas of analysis and evaluation on the development of green building technology,and then sums up the carbon neutral background the priority areas and tasks for the development of green building techniques,optimization of the construction industry into a new era under the background of green development to provide the reference.