• Journal of Bio-Environment Control
• /
• v.9 no.1
• /
• pp.1-10
• /
• 2000

This study was performed to find an efficient method to overcome extremely high temperature in greenhouses during summer season. The actual utilization of greenhouses during hot summer season showed that about 21.6％ of the investigated greenhouse farms were in fallow state, and most of greenhouse farms were cultivated under the very inferior environment. Thermal environment of greenhouses according to the evaporative cooling method and several assistant cooling methods such as ventilation, shading screen, roof sprinkling were examined. As the each assistant cooling method was used, about 74.8％, 25.9％, and 58.2％ of temperatures measured at intervals of ten minutes between ten and seventeen o'clock were above 35$^{\circ}C$. When shading screen and evaporative cooling system were operated, most greenhouse air temperatures were maintained below 35$^{\circ}C$, and showed a drop of 3.8~4.2$^{\circ}C$ as compared with naturally ventilated greenhouse.

• Journal of the Korean Solar Energy Society
• /
• v.27 no.3
• /
• pp.169-174
• /
• 2007

Building integrated photovoltaic(BIPV) system operates as a multi-functional building construction material. They not only produce electricity, but also are building integral components such as facade, roof, window and shading device. As PV modules function like building envelope in BIPV, combined thermal and PV performance should be simultaneously evaluated. This study is to establish basic Information for designing effective BIPV by discovering relations between temperature and generation capability through experiment when the PV module is used as roof material for houses. To do so, we established 3kW full scale mock-up model with real size house and attached an PV array by cutting in half. This is to assess temperature influence depending on whether there is a ventilation on the rear side of PV module or not.

• Journal of Animal Environmental Science
• /
• v.15 no.3
• /
• pp.231-240
• /
• 2009

In this research pig house facilities what are 3,029 houses hold over 1000 heads were surveyed by scale and province. Full-time farms hold over 1000 heads breed total 7,229,892 heads. And farms breed 2,386.9 heads averagely. Pig houses were constructed august 1995 averagely. Each of houses have $3,017.2\;m^2$ scale. The construction type of pig house was winch-curtain type 77.2% which was most popular, confined type 51.3%, litter type 7.4% and loft type 4.6%. The winch-curtain type was popular than windowless type in pig farms which have 1,000-1,999 heads. But pig house construction type which have more than over 10,000 heads was windowless type more than winch-curtain type. Manure removing type was slurry 72.3% and scraper 38.5% in farms which have 1,000-1,999 heads. Manure removing type was slurry 83.3% in farms which have over 10,000 heads. Proportion of roof type of pig house was slate 51.2%, panel 46.1%. But in middle or small farms, slate type was only 25.0%. Proportion of wall type of pig house was 41.9%, block 21.9%, concrete 7.6%, winch-curtain 6.3%, and bnck 5.9%. Ventilation type of pig house was natural winch 46.1%, mechanical windowless 69.8% and mixed type 53.1%. So, mechanical windowless type was popular than natural winch type. Especially the farm scale is bigger the mechanical widowless type was more. Utilization period of pig house was 8.1 years about automatic feeder, 8.3 years about waterer, 8.2 years about electric facilities and 9.0 years about floor material. Thus, almost of facilities were used at least 8 years.

• Journal of the Korean Wood Science and Technology
• /
• v.2 no.2
• /
• pp.32-34
• /
• 1974

The important results which have been obtained in the investigation can be recapitulated as follows. 1. As demonstrated by the experimental results and analyses concerning their effects in the on-ground type mushroom house, the constructions in relation to the side wall and ceiling of the experimental house showed a sufficient heat insulation on effect to protect insides of the house from outside climatic conditions. 2. As the effect on the solar type experimental mushroom house which was constructed in a half basement has been shown by the experimental results and analyses, it has been proved to be effective for making use of solar heat. However there were found two problems to be improved for putting solar house to practical use in the farm mushroom growing: (1) the construction of the roof and ceiling should be the same as for the on ground type house, and (2) the solar heat generating system should be reconstructed properly. 3. Among several ventilation systems which have been studied in the experiments, the underground earthen pipe and ceiling ventilation, and vertical side wall and ceiling ventilation systems have been proved to be most effective for natural ventilation. 4. The experimental results have shown that ventilation systems such as the vertical side wall and underground ventilation systems are suitable to put to practical use as natural ventilation systems for farm mushroom house. These ventilation systems can remarkably improve the temperature of fresh air which is introduced into the house by heat transfers within the ventilation passages, so as to approach to the desired temperature of the house without any cooling or heating operation. For example, if it is assuming that X is the outside temperature and Y is the amount of temperature adjustment made by the influence of the ventilation system, the relationships that exist between X and Y can be expressed by the following regression lines. Underground iron pipe ventilation system. Y=0.9X-12.8 Underground earthen pipe ventilation system. Y=0.96X-15.11 Vertical side wall ventilation system. Y=0.94X-17.57 5. The experimental results have 8hown that the relationships existing between the admitted and expelled air and the $CO_2$ concentration can be described with experimental regression lines or an exponent equation as follows: 5.1 If it is assumed that X is an air speed cm/sec. and Y is an expelled air speed in cm/sec. in a natural ventilation system, since the Y is a function of the X, the relationships that exist between X and Y can be expressed by the regression lines shown below: 5.2 If it IS assumed that X is an admitted volume of air in $m^3$/hr. and Y is an expelled volume of air in $m^3$/hr. in a natural ventilation system, since the Y is a function of the X, the relationships that exist between X and Y can be expressed by the regression lines shown below. 5.3 If it is assumed that expelled air speed in emisec. and replacement air speed in cm/sec. at the bed surface in a natural ventilation system are shown as X and Y. respectively, since the Y is a function of the X. the relationships that exist between X and Y can be expressed by the following regression line: GE(100%)-CV (50%) ventilation system. Y=-0.54X+0.84 5.4 If it is assumed that the replacement air speed in cm/sec. at the bed surface is shown as X, and $CO_2$ concentration which is expressed by multiplying 1000 times the actual value of $CO_2$ % is shown as Y, in a natural ventilation system, since the Y is a function of the X, the relationships that exist between X and Y can be expressed by the following regression line: GE(100%)-CV(50%) ventilation system. Y=114.53-6.42X 5.5 If it is assumed that the expelled volume of air is shown as X and the $CO_2$ concencration which is expressed by multiplying 1000 times the actual of $CO_2$% is shown as Y in a natural ventilation system, since the Y is a function of the X, the relationships that exist between X and Y can be expressed by the following exponent equation: GE(100%)-CV(50%) ventilation system. Y=$127.18{\times}1.0093^{-x}$ 5.6 The experimental results have shown that the ratios of the cross sectional area of the GE and CV vent to the total cubic capacity of the house, required for providing an adequate amount of air in a natural ventilation system, can be estimated as follows: GE(admitting vent of the underground ventilation) 0.3-0.5% (controllable) CV(expelling vent of the ceiling ventilation) 0.8-1.0% (controllable) 6. Among several heating devices which were studied in the experiments, the hot-water boilor which wasmodified to be fitted both as hot-water boiler and as a pressureless steam-water was found most suitable for farm mushroom growing.

• Journal of Animal Environmental Science
• /
• v.16 no.2
• /
• pp.109-114
• /
• 2010

In South Korea, mora than 90% of swine barns had open-style side wall by winch operation, and less than 5% of swine barns were semi-windowless or windowless style. The aisle ventilation system of the barn was changed to roof-wall ventilation system, and the width and the length of barns were 10~12 m and 30~50 m, respectively. The width of aisle satisfying energy save was 2~3 m. The re-modeled barns inhaled air through duct which was opened to aisle and exhaled through forced ventilation fans on the windowless wall which was accomplished by installing planks on the open wall. After remodelling, the culling ratio and energy cost were decreased from 11% (47 heads) to 3% (12 heads) and from 1,550,000 won to 730,000 won, respectively. Hence, re-modeled swine barns raising 400 heads could save 2,835,680 won during winter (from December to March).

• Journal of Bio-Environment Control
• /
• v.24 no.4
• /
• pp.308-316
• /
• 2015

This study was conducted to investigate the situation of ICT apply to plastic greenhouse, and the results be apply to design of new one. A CFD analysis were conducted to monitering the ventilation and energy saving of the single span greenhouse newly designed. The causes of delay to apply ICT to plastic greenhouse are the high cost for installation(24%), insufficiency of after services(19%), often disorder(16%), unskillful management of soft ware(15%), insufficient ICT efficiency(13%) and unsatisfying of income increase(12%). The parts of problem occurred in ICT plastic greenhouse are the structure, actuator, environmental control system and sensor(approximate 14%, respectively), remote control technique(13%), plant management technique(12%), energy saving technique(10%) and utilization of software(8%). In the condition of lateral window closed, the average wind speed changed to slow, but it was faster in the condition of leeward side window opened than in the condition of lee and winward side window opened. The air movement in the condition of lateral window closed occur by air moving fan not by out air. It is not affect the room temperature but effective the uniformity of room temperature. The average temperature of low height greenhouse was uniform than high height one. The average temperature in condition of 3rd curtain opened become same with outside temperature after 2 hours, but take more 5 hours in condition of 3rd curtain closed.

• Journal of Animal Environmental Science
• /
• v.15 no.3
• /
• pp.189-198
• /
• 2009

This survey was conducted to investigate the situation of housing type in poultry farms in Korea. The number surveyed among the farm size over 30,000 heads was 1,965 farms. Poultry housing types of windowless, open sided, vinyl house type were 19.0, 47.7, 19.8%, respectively. Waterers of nipple, bell, and 8 feet trough used in smaller than 50,000 heads of poultry farm were 40.6, 11.3 and 42.8%, respectively. But the bigger farm in the farm size of over 100,000 heads used more nipple waterer. Feeders of disk, hopper and chain used in poultry farm were 54.5, 16.3, 15.8%, respectively. Manure collecting system of scraper and belt was 29.4, 71.5 %, respectively. Ventilation systems of natural ventilation, natural + mechanical ventilation, mechanical ventilation were 40.5, 39.8, 20.7%, respectively.

• Journal of Bio-Environment Control
• /
• v.13 no.4
• /
• pp.217-225
• /
• 2004

This study was performed to provide the basic knowledge about the mushroom cultivation facilities. Classified current status of cultivation facilities in Gyeongnam province was investigated by questionnaire. The structure of Pleurotus eryngii cultivation facilities can be classified into the simple and permanent frame type. The simple frame structures were mostly single-span type, on the other hand, the permanent frame structures were more multi-span than simple structures. And the scale of cultivation facilities was very different regardless of structural type. But as a whole, the length, width and ridge height were prevailing approximately 20.0 m, $6.6\~7.0m$ and $4.6\~5.0m$ range, respectively. The floor area was about $132\~160\;m^2$, and floor was built with concrete to protect mushrooms from various harmful infection. The roof slope of the simple and permanent type showed about $41.5^{\circ}\;and\;18.6\~28.6^{\circ}$, respectively. The width and layer number of growing bed for mushroom cultivation were around $1.2\~1.6m$, 4 layers in common, respectively. Most of year round cultivation facilities were equipped with cooler, heater, humidifier, and ventilating fan. Hot water boiler was the most commonly used heating system, the next was electric heater and then steam boiler. The industrial air conditioner has been widely used for cooling. And humidity was controlled mostly by ultra-wave or centrifuging humidifier. But some farmers has been using nozzle system for auxiliary purpose. More then $90\%$ of the mushroom house had the independent environment control system. The inside temperature was usually controlled by sensor, but humidity and $CO_2$ concentration was controlled by timer for each growing stage. The capacity of medium bottle was generally 850 cc and 1100cc, some farms used 800 cc, 950 co and 1,250 cc. Most of mushroom producted has been usually shipped to both circulating company and joint market.

• Journal of Bio-Environment Control
• /
• v.31 no.3
• /
• pp.221-229
• /
• 2022

This study was aimed to investigate spatial and vertical characteristics of greenhouse environments according to the location of the environmental sensors, and to investigate the correlations between temperature, light intensity, and carbon dioxide (CO₂) concentration according to the type of greenhouse. Temperature, relative humidity (RH), CO₂, and light sensors were installed in the four-different vertical positions of the whole canopy as well as ground and roof space at the five spatial locations of the Venlo greenhouse. Also, correlations between temperature, light intensity, and CO₂ concentration in Venlo and semi-closed greenhouses were analyzed using the Curve Expert Professional program. The deviations among the spatial locations were larger in the CO₂ concentration than other environmental factors in the Venlo greenhouse. The average CO₂ concentration ranged from 465 to 761 µmol·mol^-1 with the highest value (646 µmol·mol^-1) at the Middle End (4ME) close to the main pipe (50Ø) of the liquefied CO₂ gas supply and lowest (436 µmol·mol^-1) at the Left Middle (5LM). The deviation among the vertical positions was greater in temperature and relative humidity than other environments. The time zone with the largest deviation in average temperature was 2 p.m. with the highest temperature (26.51℃) at the Upper Air (UA) and the lowest temperature (25.62℃) at the Lower Canopy (LC). The time zone with the largest deviation in average RH was 1 p.m. with the highest RH (76.90%) at the LC and the lowest RH (71.74%) at the UA. The highest average CO₂ concentration at each hour was Roof Air (RF) and Ground (GD). The coefficient of correlations between temperature, light intensity, and CO₂ concentration were 0.07 for semi-closed greenhouse and 0.66 for Venlo greenhouse. All the results indicate that while the CO₂ concentration in the greenhouse needs to be analyzed in the spatial locations, temperature and humidity needs to be analyzed in the vertical positions of canopy. The target CO₂ fertilization concentration for the semi-closed greenhouse with low ventilation rate should be different from that of general greenhouses.

• Journal of Bio-Environment Control
• /
• v.24 no.3
• /
• pp.252-257
• /
• 2015

Fruit cracking and vine leaf spot of grapes tend to occur when the plants were directly exposed to rain under outdoor culture. Rain shelter facility can be an alternative method to prevent the cracking and disease of grape, but it also has some limitations in practical usages. We designed rain shelter facility which can completely shut out the rain and ventilate naturally, and it was upgraded to meet the standards of disaster prevention against snow and wind load. The newly developed rain shelter has two-story roof structure, and the $2^{nd}$ floor roof was equipped over $1^{st}$ floor roof at a distance of 40cm. For natural ventilation and water proof, the upper roof protruded about 50cm from the ridge of a $1^{st}$ floor roof. The various tests were carried to examine such as grape quality, brown spot and fruit cracking of Campbell Early under the conventional and the newly developed rain shelter facility which was built about $100{\ss}{\check{S}}$. In comparison of temperature between the conventional and the newly developed rain shelter facility when outside temperature was more than $34^{\circ}C$, the inside temperature was recorded as $40.7^{\circ}C$ and $37.4^{\circ}C$, respectively. There was no significant difference between the two facilities when outside was below $32^{\circ}C$ The quality such as soluble solids and marketable fruit was increased, and fruit cracking of grapes and vine leaf spot also drastically diminished in the newly developed rain shelter.