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Field Survey of Greenhouse for Strawberry Culture -Case Study Based on Western Gyeongnam Area- (딸기재배 온실의 현장조사 분석 -서부경남 지역을 중심으로-)

  • Jeong, Young Kyun;Lee, Jong Goo;Yun, Sung Wook;Kim, Hyeon Tae;Yoon, Yong Cheol
    • Journal of Bio-Environment Control
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    • v.27 no.3
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    • pp.253-259
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    • 2018
  • This study set out to select a system to realize an optimal environment for strawberry cultivation greenhouses based on data about the growth and development of strawberry and its environment and to provide basic data for the research of its improved productivity. For these purposes, the investigator conducted a field survey with greenhouses for strawberry cultivation in western Gyeongnam. The findings show that farmers in their fifties and sixties accounted for the biggest part in the age groups of strawberry farmers. While those who were under 50 were accounted for approximately 67.5%, those who were 60 or older accounted for 32.5%. As for cultivation experiences, the majority of the farmers had ten years of cultivation experiences or less with some having 30 years of cultivation experiences or more. All the farmers built an arch type single span greenhouse. Those who used nutrient solutions were about 75.0%, being more than those who used soil. All of the farmers that used a nutrient solution adopted an elevated hydroponic system. The single span greenhouses were in the range of 7.5~8.5m, 1.3~1.8m and 2.5~3.5m for width, eaves, and ridge height, respectively, regardless of survey areas. The rafters interval was about 0.7~0.8m. In elevated hydroponic cultivation, the width, height, and interval of the beds were about 0.25m, 1.2m and 1.0m, respectively. As for the strawberry varieties, the domestic ones accounted for approximately 97.5% with Seolhyang being the most favorite one at about 65.0%. As for the internal environment factors of greenhouses, 38 farmers measured only temperature and relatively humidity. As for hydroponics, the farmers used a hydroponics control system. Except for the farmers that introduced a smart farm system for temperature and humidity control, approximately 85.0% controlled temperature and humidity only with a control panel for side windows and ventilation fans. As for heating and heat insulation, all of the farmers were using water curtains with many farmers using an oil or electric boiler, radiating lamp or non-woven fabric, as well, when necessary.

Field Survey on Smart Greenhouse (스마트 온실의 현장조사 분석)

  • Lee, Jong Goo;Jeong, Young Kyun;Yun, Sung Wook;Choi, Man Kwon;Kim, Hyeon Tae;Yoon, Yong Cheol
    • Journal of Bio-Environment Control
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    • v.27 no.2
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    • pp.166-172
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    • 2018
  • This study set out to conduct a field survey with smart greenhouse-based farms in seven types to figure out the actual state of smart greenhouses distributed across the nation before selecting a system to implement an optimal greenhouse environment and doing a research on higher productivity based on data related to crop growth, development, and environment. The findings show that the farms were close to an intelligent or advanced smart farm, given the main purposes of leading cases across the smart farm types found in the field. As for the age of farmers, those who were in their forties and sixties accounted for the biggest percentage, but those who were in their fifties or younger ran 21 farms that accounted for approximately 70.0%. The biggest number of farmers had a cultivation career of ten years or less. As for the greenhouse type, the 1-2W type accounted for 50.0%, and the multispan type accounted for 80.0% at 24 farms. As for crops they cultivated, only three farms cultivated flowers with the remaining farms growing only fruit vegetables, of which the tomato and paprika accounted for approximately 63.6%. As for control systems, approximately 77.4% (24 farms) used a domestic control system. As for the control method of a control system, three farms regulated temperature and humidity only with a control panel with the remaining farms adopting a digital control method to combine a panel with a computer. There were total nine environmental factors to measure and control including temperature. While all the surveyed farms measured temperature, the number of farms installing a ventilation or air flow fan or measuring the concentration of carbon dioxide was relatively small. As for a heating system, 46.7% of the farms used an electric boiler. In addition, hot water boilers, heat pumps, and lamp oil boilers were used. As for investment into a control system, there was a difference in the investment scale among the farms from 10 million won to 100 million won. As for difficulties with greenhouse management, the farmers complained about difficulties with using a smart phone and digital control system due to their old age and the utter absence of education and materials about smart greenhouse management. Those difficulties were followed by high fees paid to a consultant and system malfunction in the order.

A Baseline Survey on Development of Primary Health Care in the Rural Korea -Sanpuk Village, Kumsa-Myun, Yuju- Gun, Kyunggi-Do- (농촌지역의 일차보건사업 개발을 위한 기초조사 연구 - 경기도 여주군 금사면 산북부락을 중심으로 -)

  • Kim, Myung-Ho;Yun, Suk-Woo;Rhee, Hae-Soak
    • Journal of agricultural medicine and community health
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    • v.12 no.1
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    • pp.5-27
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    • 1987
  • It is widely recognized that primary health care in the community is one of the most important and effective health measures in these days. However, it is reality that unsatisfactory health care system, ineffective utilization of health care by the community people in the rural area are hampering better understanding for primary health care. Therefore promoting health for the rural people and increasing understanding about primary health care, the baseline survey in the community focused in examination for safe community water supply was carried out. The survey was conducted through August 25-31, 1986 in order to find out health problems and relevant factors and to define the demographic characteristics of $^*$Sanpuk village, Kumsa-Myun, Yuju-Gun, Kyunggi-Do, Korea. Household survey was carried out for every home by trained interviewers. The major results are found out as follows : 1) 84.2%(400 houses) of total households were surveyed because 15.8%(75 houses) were unable to survey due to either refusal against interview or absence of family. These 400 households were composed of 1,697 residents(male:830, female 867). Educational level of respondents showed 34.1% as elementary school graduated. Religion distribution showed Buddism(23.8%) as the most dominant. 50.7% of respondents married in the area. 2) Most households(91.5%) have lived in their own house in Sanpuk area. Average family size showed 4.3. More than half of residents(64.2%) have used public supplied water tap. Only 1.5% of the households had a flush toliet. The rest of households have still used primitive insanitary latrines. 3) 32.5% of residents have used gas burner for cooking and for heating in the house, and the coal briquet were used for boiler. Lack of convenient public transportation was the chief complaint for their day life. 4) Each household occupied 1,990 pyungs of rice paddy and 1,170 pyungs of ordinary field in average. Beside farming products, mushroom was the highest product. 5) Sixth percent of households in the survey area regularly participated in community meeting one hand and on the other hand 39.5% never participated. Most of respondents closely contacted with their neighbours and they seemed very friendly each other. 6) The prevalence rate of illness and injury during recent 15 days showed 48.3 per 1,000. The prevalence rate of chronic illnesses during the past one year showed 74 per 1,000. Injury and accident lead the higher portion(22.0%) in the former and in the latter pain(arthritis, back-pain) showed 27.0% as the dominant sickness. 87.8% of the ill residents in the former received medical treatment. As the most frequently utilized medical facility, the clinic or hospital were counted. Among the residents suffering from chronic illnesses, 77.3% in Sanpuk area get some kind of medical treatments and they rarely utilized the clinic or hospital. The reason why the patient did not receive any medical care was found out the fact that symptoms of illness was light or mild and economic problems was serious. 7) Average age of marriage showed 21.6 years old in the women and the average duration of marital period was shown for 15.1 years. The married woman in reproductive age in Sanpuk area had experienced pregnancies 4 times in the aver-age including 0.7 time of pregnancy in average were interrupted by induced abortion and 0.3 time by spontaneous abortion respectively. The practicing rate of the family planning of the married woman during reproductive ages showed 70.7% and the tuballigation was found out as the most frequently used contraceptives. 8) Among woman who has children under 2 years old, 70.0% had received the prenatal care for the last pregnancy. However, the average number of prenatal care visitis per woman showed 3.3 times. Fifty-two % of woman who received the postnatal care for the last delivery showed only 37.5%. 9) Immunization rate of the children under 2 years old showed relatively high and looked successful. The breast feeding for these children showed dominantly in the most. Most of the mothers in Sanpuk area had started the supplementary diet during weaning period of their infants of 6th and 7th month after birth. * : Sanpuk area is a demstration area for community development which has been supported by the Community Development Foundation during the part 10 years. The village is relatively closer to urban area such as Seoul, However, it has a similar characteristics shown as a remote village because of geographical location and inconvenient transportation at present.

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Study on the Controlling Mechaniques of the Environmental Factors in the Mushroom Growing House in Chonnam Province (전남 지방에 있어서의 양송이 재배에 최적한 환경조건 조절법 분석에 관한 연구)

  • Chung, Byung-Jae;Lee, Eun-Chol
    • Journal of the Korean Wood Science and Technology
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    • v.2 no.2
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    • pp.32-34
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    • 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.

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