The design of housing systems is today challenged by a highly uncertain context, dominated by the rapid development of functional and technological obsolescence in inherited housing models. If flexibility is the abili...The design of housing systems is today challenged by a highly uncertain context, dominated by the rapid development of functional and technological obsolescence in inherited housing models. If flexibility is the ability of a system to be easily modified and to respond to changes in the environment timely and conveniently, it can be considered as the antidote to obsolescence or the characteristic of the system that guarantees slippage over time. Our paper focuses on the concept of flexibility as a fundamental prerequisite for residential building in order to extend its life cycle design, through strategies and constructive solutions that ensure both the convertibility of the space in response to changing usage and the use of building materials that encourage the reversibility and the long-term easy maintenance of the technological choices that have been implemented. Flexibility is examined both from a conceptual point of view, so as to obtain a clear and logical definition that is distinct from related terms, as well as from a practical point of view, by finding ways to incorporate this requirement into the designing of housing.展开更多
Uniformity of air flow in extraction openings in exhaust air channels for manure gas exhaustion is determined by the distribution of pressure. The areas required in extraction vents and in extraction ducts are determi...Uniformity of air flow in extraction openings in exhaust air channels for manure gas exhaustion is determined by the distribution of pressure. The areas required in extraction vents and in extraction ducts are determined by the uniformity of air flow desired along the duct and by the loss of pressure that can be accepted. The area ratio between the vents and the cross section of the exhaust air duct will have a strong influence on both uniformity of flow and loss of pressure. The following ventilation properties were studied： Uniformity of air flow; Variations in static pressure along a duct; Air velocity at different distances from the vents. The area ratio should be about 1 for uniform exhaustion. The studies showed that the relative variation in air velocity is independent of the level of the ventilation rate. The uniformity of the exhaust distance is influenced in about the same way by the area ratio as the air velocity in the exhaust vents. Thus, it is important that the area ratio is not too high if a good exhaust function should be guaranteed. The studies also demonstrated that the uniformity of the exhaust distance is independent of the ventilation flow rate. The exhaust ventilation range is, maximally 0.3 m from the vents. The static friction coefficient was on average 0.80.展开更多
How different factors and techniques affect concentration and generation of dust in a floor housing system for laying hens was investigated in a climate chamber. The efficiencies of different dust reducing measures we...How different factors and techniques affect concentration and generation of dust in a floor housing system for laying hens was investigated in a climate chamber. The efficiencies of different dust reducing measures were investigated. A major part of the generated dust settled on different surfaces inside the building. The settling rate of dust was affected by the concentration of dust in the air. The settled amount of dust also stood in relation to the floor area of the stable. An increased ventilation rate had a limited effect on the concentration of total dust due to the importance of the settling of the dust. The generation of dust was also investigated when using six different bedding materials, namely： gravel, clay pellets, peat, wood shavings, chopped straw and chopped paper. Clay pellets and peat resulted in the lowest concentrations of dust. Automatic spraying of small droplets of water reduced the dust concentration in four trials with different bedding materials （chopped paper, clay pellets, peat and wood shavings）. Spraying a mixture of rapeseed oil in water was also effective with an automatic spraying system.展开更多
Investigations about laying hens reactions on artificial light conditions were carried out in a climate chamber equipped with a floor housing system for laying hens. The release of moisture increased during light peri...Investigations about laying hens reactions on artificial light conditions were carried out in a climate chamber equipped with a floor housing system for laying hens. The release of moisture increased during light periods probably due to increased activity which increased respiration rate but also on increased scratching which increased evaporation of moisture from bedding material. The daily average was 6.29 g henl h＂l at 4 lux and 5.97 g henl hl, at 93 lux which corresponds to a difference of 5%. The level of light intensity seemed to have little influence on the release of moisture. The total release of heat was slightly higher during light periods compared to dark periods. Explanations can be increased activity but also feed intake increasing the metabolic rate during light periods. The daily average of total heat production was 17.0 W per hen at 4 lux and 14.7 at 93 lux which corresponds to a difference of 16%. The release of carbon dioxide increased during light periods probably due to increased activity and respiration.展开更多
The hygienic threshold limit values for ammonia （25 ppm） for animal welfare but also for occupational safety and health is often exceeded in floor housing systems for laying hens with long time storage of manure in ...The hygienic threshold limit values for ammonia （25 ppm） for animal welfare but also for occupational safety and health is often exceeded in floor housing systems for laying hens with long time storage of manure in bins below draining floors. The major reason for high ammonia concentrations is the large amounts of stored and exposed manure. The possibility to reduce ammonia release by reducing the amount of stored manure in bins in floor housing systems for laying hens has therefore been investigated. Investigations were carried out in a climate chamber equipped with a floor housing system with a manure removal system with two parallel motor driven conveyors placed below an elevated draining floor. The conditions when manure is stored in bins below draining floors were simulated by storing manure on the conveyors for several days at constant ventilation rates and temperatures. The investigations clearly showed that storage of manure in the bin caused a rapid increase in ammonia concentrations. After about 7 days storage of manure in the bin the ammonia concentration exceeded the hygienic threshold limit values. It can be concluded that long time storage of manure in storage bins below draining floors should not be recommended. It was possible to maintain the ammonia concentration below the hygienic threshold limit values when manure was removed frequently with conveyors. Floor housing systems for laying hens with elevated draining floors should therefore be equipped with manure removal systems that enable frequent removal of manure in the bins.展开更多
Along the rapid urbanization, the housing problem of medium and low-income residents in cities has been one of social problems, which is drawing the attention of government in the world for a long time. In present Chi...Along the rapid urbanization, the housing problem of medium and low-income residents in cities has been one of social problems, which is drawing the attention of government in the world for a long time. In present China, both the national policy and market of housing system are in the process of perfecting, which pay more attention to the low-income residents and rural residents. This paper chooses Tianjin, the third pole of China development as the example for research. Tianjin public housing residential district planning explored a mode of ＂large-scale mix and small-scale pure＂ for the whole homeland development. It confirms that regional coordination, ecological concepts, green transport, space characteristics and appropriate technology is important in planning.展开更多
In the 1990s, China＇s urban housing reform in full swing. With the development of housing commercialization, the housing accumulation fund system in our country has come into being, which rapidly focus on development...In the 1990s, China＇s urban housing reform in full swing. With the development of housing commercialization, the housing accumulation fund system in our country has come into being, which rapidly focus on development and perfection. At the same time, the public accumulation fund for housing construction funds collection amount has reached a certain scale, which not only effectively play the function of housing security, but also precipitate more balance a lot of money.The appreciation will to be solved.展开更多
China has entered the aging society, due to the imperfect national endowment insurance system, the traditional pension mode can no longer meet the needs of old people, so that the family pension and social pension are...China has entered the aging society, due to the imperfect national endowment insurance system, the traditional pension mode can no longer meet the needs of old people, so that the family pension and social pension are facing tremendous pressure. In this paper, firstly, explaining the concept of the housing endowment, and summarizing the feasibility and necessity of the housing endowment. Then through the investigation and the analysis of SPSS data, with the housing endowment in the United States and Singapore＇ success, summing up what our country should do to make improvements, and then we will induce the current situation and predicament of the housing endowment in Nanjing. Finally, we can put forward relevant countermeasures and suggestions by the feasibility to the reality to Nanjing city in the future.展开更多
文摘The design of housing systems is today challenged by a highly uncertain context, dominated by the rapid development of functional and technological obsolescence in inherited housing models. If flexibility is the ability of a system to be easily modified and to respond to changes in the environment timely and conveniently, it can be considered as the antidote to obsolescence or the characteristic of the system that guarantees slippage over time. Our paper focuses on the concept of flexibility as a fundamental prerequisite for residential building in order to extend its life cycle design, through strategies and constructive solutions that ensure both the convertibility of the space in response to changing usage and the use of building materials that encourage the reversibility and the long-term easy maintenance of the technological choices that have been implemented. Flexibility is examined both from a conceptual point of view, so as to obtain a clear and logical definition that is distinct from related terms, as well as from a practical point of view, by finding ways to incorporate this requirement into the designing of housing.
文摘Uniformity of air flow in extraction openings in exhaust air channels for manure gas exhaustion is determined by the distribution of pressure. The areas required in extraction vents and in extraction ducts are determined by the uniformity of air flow desired along the duct and by the loss of pressure that can be accepted. The area ratio between the vents and the cross section of the exhaust air duct will have a strong influence on both uniformity of flow and loss of pressure. The following ventilation properties were studied： Uniformity of air flow; Variations in static pressure along a duct; Air velocity at different distances from the vents. The area ratio should be about 1 for uniform exhaustion. The studies showed that the relative variation in air velocity is independent of the level of the ventilation rate. The uniformity of the exhaust distance is influenced in about the same way by the area ratio as the air velocity in the exhaust vents. Thus, it is important that the area ratio is not too high if a good exhaust function should be guaranteed. The studies also demonstrated that the uniformity of the exhaust distance is independent of the ventilation flow rate. The exhaust ventilation range is, maximally 0.3 m from the vents. The static friction coefficient was on average 0.80.
文摘How different factors and techniques affect concentration and generation of dust in a floor housing system for laying hens was investigated in a climate chamber. The efficiencies of different dust reducing measures were investigated. A major part of the generated dust settled on different surfaces inside the building. The settling rate of dust was affected by the concentration of dust in the air. The settled amount of dust also stood in relation to the floor area of the stable. An increased ventilation rate had a limited effect on the concentration of total dust due to the importance of the settling of the dust. The generation of dust was also investigated when using six different bedding materials, namely： gravel, clay pellets, peat, wood shavings, chopped straw and chopped paper. Clay pellets and peat resulted in the lowest concentrations of dust. Automatic spraying of small droplets of water reduced the dust concentration in four trials with different bedding materials （chopped paper, clay pellets, peat and wood shavings）. Spraying a mixture of rapeseed oil in water was also effective with an automatic spraying system.
文摘Investigations about laying hens reactions on artificial light conditions were carried out in a climate chamber equipped with a floor housing system for laying hens. The release of moisture increased during light periods probably due to increased activity which increased respiration rate but also on increased scratching which increased evaporation of moisture from bedding material. The daily average was 6.29 g henl h＂l at 4 lux and 5.97 g henl hl, at 93 lux which corresponds to a difference of 5%. The level of light intensity seemed to have little influence on the release of moisture. The total release of heat was slightly higher during light periods compared to dark periods. Explanations can be increased activity but also feed intake increasing the metabolic rate during light periods. The daily average of total heat production was 17.0 W per hen at 4 lux and 14.7 at 93 lux which corresponds to a difference of 16%. The release of carbon dioxide increased during light periods probably due to increased activity and respiration.
文摘The hygienic threshold limit values for ammonia （25 ppm） for animal welfare but also for occupational safety and health is often exceeded in floor housing systems for laying hens with long time storage of manure in bins below draining floors. The major reason for high ammonia concentrations is the large amounts of stored and exposed manure. The possibility to reduce ammonia release by reducing the amount of stored manure in bins in floor housing systems for laying hens has therefore been investigated. Investigations were carried out in a climate chamber equipped with a floor housing system with a manure removal system with two parallel motor driven conveyors placed below an elevated draining floor. The conditions when manure is stored in bins below draining floors were simulated by storing manure on the conveyors for several days at constant ventilation rates and temperatures. The investigations clearly showed that storage of manure in the bin caused a rapid increase in ammonia concentrations. After about 7 days storage of manure in the bin the ammonia concentration exceeded the hygienic threshold limit values. It can be concluded that long time storage of manure in storage bins below draining floors should not be recommended. It was possible to maintain the ammonia concentration below the hygienic threshold limit values when manure was removed frequently with conveyors. Floor housing systems for laying hens with elevated draining floors should therefore be equipped with manure removal systems that enable frequent removal of manure in the bins.
文摘Along the rapid urbanization, the housing problem of medium and low-income residents in cities has been one of social problems, which is drawing the attention of government in the world for a long time. In present China, both the national policy and market of housing system are in the process of perfecting, which pay more attention to the low-income residents and rural residents. This paper chooses Tianjin, the third pole of China development as the example for research. Tianjin public housing residential district planning explored a mode of ＂large-scale mix and small-scale pure＂ for the whole homeland development. It confirms that regional coordination, ecological concepts, green transport, space characteristics and appropriate technology is important in planning.
文摘In the 1990s, China＇s urban housing reform in full swing. With the development of housing commercialization, the housing accumulation fund system in our country has come into being, which rapidly focus on development and perfection. At the same time, the public accumulation fund for housing construction funds collection amount has reached a certain scale, which not only effectively play the function of housing security, but also precipitate more balance a lot of money.The appreciation will to be solved.
文摘China has entered the aging society, due to the imperfect national endowment insurance system, the traditional pension mode can no longer meet the needs of old people, so that the family pension and social pension are facing tremendous pressure. In this paper, firstly, explaining the concept of the housing endowment, and summarizing the feasibility and necessity of the housing endowment. Then through the investigation and the analysis of SPSS data, with the housing endowment in the United States and Singapore＇ success, summing up what our country should do to make improvements, and then we will induce the current situation and predicament of the housing endowment in Nanjing. Finally, we can put forward relevant countermeasures and suggestions by the feasibility to the reality to Nanjing city in the future.
