• Title/Summary/Keyword: Dependent Variables

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The Health Status of Rural Farming Women (농촌여성(農村女性)의 건강실태(健康實態)에 관한 연구(硏究))

  • Park, Jung-Eun
    • Journal of agricultural medicine and community health
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    • v.15 no.2
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    • pp.97-106
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    • 1990
  • 1. Background Women's health and their involvement in health care are essential to health for everyone. If they are ignorant, malnourished or over-worked, the health &-their families as well as their own health will suffer. Women's health depends on broad considerations beyond medicine. Among other things, it depends upon their work in farming. their subordination to their families, their accepted roles, and poor hygiene with poorly equipped housing and environmental sanitation. 2. Objectives and Contents a. The health status of rural women : physical and mental complaints, experience of pesticides intoxication, Farmer's syndrome, experiences of reproductive health problems. b. participation in and attitudes towards housework and farming c. accessibility of medical care d. status of maternal health : fertility, family planning practice. induced abortion, and maternal care 3. Research method A nationwide field survey, based on stratified random sampling, was conducted during July, 1986. Revised Cornell Medical index(68 out of 195 items). Kawagai's Farmers Syndrome Scale, and self-developed structured questionnaires were used to rural farming wives(n=2.028). aged between 26-55. 4. Characteristics of the respondents mean age : 40.2 marital status : 90.8% married mean no. of household : 4.9 average years of education : 4.7 yrs. average income of household : \235,000 average years of residence in rural area : 36.4 yrs average Working hours(household and farming) : 11 hrs. 23 min 5. Health Status of rural women a. The average number of physical and mental symptoms were 12.4, 4.7, and the rate of complaints were 22.1%, 38.8% each. revealing complaints of mental symptomes higher than physical ones. b. 65.4% of rural women complained of more than 4 symptoms out of 9, indicating farmer's syndrome. 11.9 % experienced pesticide overdue syndrome c. 57.6% of respondents experienced women-specific health problems. d. Age and education of respondents were the variables which affect on the level of their health 6. Utilization of medical services a. The number of symptoms and complaints of respondents were dependent on the distance to where the health-care service is given b. Drug store was the most commonly utilized due to low price and the distance to reach. while nurse practitioners were well utilized when there were nurse practitioner's office in their villages. c. Rural women were internalized their subordination to husbands and children, revealing they are positive(93%) in health-care demand for-them but negative(30%) for themselves d. 33.0% of respondents were habitual drug users, 4.5% were smokers and 32.3% were alcohol drinkers. and 86.3% experienced induced-abortion. But most of them(77.6%) knew that those had negative effects on health. 7. Maternal Health Care a. Practice rate of contraception was 48.1% : female users were 90.9% in permanent and 89.6% in temporary contraception b. Induced abortions were taken mostly at hospital(86.3%), while health centers(4.7%), midwiferies(4.3%). and others(4.5%) including drug stores were listed a few. The repeated numbers of induced abortion seemed affected on the increasing numbers of symptoms and complaints. c. The first pre-natal check-up during first trimester was 41.8%, safe delivery rate was 15.6%, post-natal check-up during two months after delivery. Rural women had no enough rest after delivery revealing average days of rest from home work and farming 8.3 and 17.2. d. 86.6% practised breast feeding, showing younger and more educated mothers depending on artificial milk 8. Recommendations a. To lessen the multiple role over burden housing and sanitary conditions should be improved, and are needed farming machiner es for women and training on the use of them b. Health education should begin at primary school including health behavior and living environment. c. Women should be encouraged to become policy-makers as well as administrators in the field of women specific health affairs. d. Women's health indicators should be developed and women's health surveillance system too.

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An Analysis on Factors Related to the Job Satisfaction of Dental Hygienists at J Region (J지역 치과위생사의 직무스트레스 요인 분석)

  • Lee, Hyun-Ok;Ju, On-Ju;Kim, Young-Im
    • Journal of dental hygiene science
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    • v.7 no.2
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    • pp.65-72
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    • 2007
  • The purpose of this study was to examine the job stress and job stressors of dental hygienists. The subjects in the study were 220 dental hygienists who worked in north Jeolla province. After a mail survey was conducted from July 24 through September 24, 2006, the responses from 180 dental hygienists(response rate 81.8%) were gathered, and 156 answer sheets were analyzed except 24 incomplete ones that couldn't be analyzable. The findings of the study were as follows: 1. As for the correlation of overall job stress to turnover intention, their entire stress was under the influence of unreasonable treatment (r = 0.382), conflicts as a professional(r = 0.285), tough working environments(r = 0.303), conflicts with colleagues(r = 0.233), and heavy workload (r = 0.262). Those who were more stressed were more willing to change their occupation, and their stress level made a statistically significant difference to that(p < 0.01). 2. A multiple regression analysis was carried out by selecting the job stressors and turnover intention as independent and dependent variables respectively to see how each of the stressors affected job stress. And unreasonable treatment(p < 0.001) was identified as what had the biggest impact on that, followed by conflicts as a professional(p < 0.05), and tough working environments (p < 0.05). The stressors made a 22.2% prediction of turnover intention.

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Relationship of between blood lead level and lead related symptoms in low level lead exposure (저농도 연폭로에서 혈중 연농도와 자각증상과의 관계)

  • Hwang, Kyu-Yoon;Ahn, Jae-Eog;Ahn, Kyu-Dong;Lee, Byung-Kook;Kim, Joung-Soon
    • Journal of Preventive Medicine and Public Health
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    • v.24 no.2 s.34
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    • pp.181-194
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    • 1991
  • This study intended to obtain an useful information on the prevalence of subjective symptoms, and to clarify the interrelationships between blood lead and lead related symptoms in low level lead exposure. The 93 male workers exposed to lead and 56 male nonexposed workers were examined for their blood lead(PBB), Zinc-protoporphy(ZPP), hemoglobin(HB) and personnal history, and completed 15 questionnaires related to symptoms of lead absorption : also measured lead concentration in air (PBA) in the workplace. The results obtained were as follows ; 1. The means of blood lead (PBB), blood ZPP and hemoglobin (HB) among workers exposed to lead were $26.1{\pm}8.8{\mu}g/dl,\;28.3{\pm}26.0{\mu}g/dl$ and $16.2{\pm}1.2g/dl$ : whereas those of nonexposed workers were $18.7{\pm}5.1{\mu}g/dl,\;20.6{\pm}8.7{\mu}g/dl$ and $17.3{\pm}1.1g/dl$. The means of above three indicies between two groups showed significant difference statistically (p<0.05). 2. The means of blood lead (PBB), blood ZPP and hemoglobin of workers exposed .to different lead concentration in air were as follows : When it was below $25{\mu}g/m^3$, the indices were $24.7{\pm}79,\;26.1{\pm}26.8{\mu}g/dl\;and\;16.4{\pm}1.1g/dl$ respectively : These indices were $27.1{\pm}8.5,\;23.9{\pm}10.92{\mu}g/dl\;and\;16.2{\pm}1.3g/dl$ when the lead concentration in air was $25{\sim}50{\mu}g/m^3$ : and they were $3.4{\pm}9.3,\;42.3{\pm}31.3{\mu}g/dl\;and\;15.5{\pm}1.2g/dl$ when the concentration of lead was above $50{\mu}g/m^3$. Although there were statistical difference in blood lead and hemoglobin among three different lead concentration in air, there was no statistical difference of blood ZPP among the three groups with different exposure levels (p>0.05). 3. The most frequent by complained symptom was 'Generalized weakness and fatigue', and fewest symptom was 'Intermittent pains in abdomen' 4. Only two symptoms out of fifteen symptoms checked by themselves revealed significant difference between exposed and nonexposed groups. These were 'Intermittent pains of abdomen' and 'Joint pain or arthralgia' (p<0.05), No positive correlation was found between the levels of blood lead and symptom groups categorized as gastrointestinal, neuromuscular and constitutional symptoms, 5. Blood lead (r=0.3995) and ZPP (r=0.2837) showed statistically significant correlation with mean lead concentration in air, whereas correlations were not demonstrated between blood lead and lead related symptoms or blood ZPP and lead related symptoms. 6. Blood lead (PBB) and ZPP showed association (r=0.2466) and the equation PBB=23.75+0.0842 ZPP was derived. 7. On stepwise multiple regression, using blood lead level as a dependent variable and ZPP, hemoglobin (HB), age, work duration (WD) and symptom prevalence as a independent variables, only ZPP significantly contributed a lot to blood lead level. 8. While the ZPP measurement was found to be a good indicator in evaluating health effect of lead absorption in low level lead exposure, lead related symptoms were not sensitive enough to evaluate of lead absorption in low level exposure.

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Health Care Utilization Pattern and Its Related Factors of Low-income Population with Abnormal Results through Health Examination (저소득층 건강검진 유소견자의 의료이용 양상 및 관련요인)

  • Kwon, Bog-Soon;Kam, Sin;Han, Chang-Hyun
    • Journal of agricultural medicine and community health
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    • v.28 no.2
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    • pp.87-105
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    • 2003
  • Objectives: The purpose of this study was to examine the health care utilization pattern and its related factors of low-income population with abnormal results through health examination. Methods: Analysed data were collected through a questionnaire survey, which was given to 263 persons who 30 years or over with abnormal results through health examination at Health Center. This survey was conducted in March, 2003. This study employed Andersen's prediction model as most well known medical demand mode and data were analysed through 2-test, and multiple logistic regression analysis. Results: The proportion of medical utilization for thorough examination or treatment among study subjects was 51.0%. In multiple logistic regression analysis as dependent variable with medical utilization, the variables affecting the medical utilization were 'feeling about abnormal result(anxiety versus no anxiety: odds ratio 2.25, 95% confidence intervals 1.07-4.75)', 'type of health security(medicaid type I versus health insurance: odds ratio 2.82, 95% confidence intervals 1.04-7.66; medicaid type II versus health insurance: odds ratio 3.22, 95% confidence intervals 1.37-7.53)', 'experience of health examination during past 2 years(odds ratio 2.39, 95% confidence intervals 1.09-5.21)' and 'family member's response for abnormal result(recommendation for medical utilization versus no response: odds ratio 4.90, 95% confidence intervals 1.75-13.75; family member recommended to utilize medical facilities with him/her versus no response: odds ratio 19.47, 95% confidence intervals 5.01-75.73)'. The time of medical utilization was 8-15 days after they received the result(29.9%), 16-30 days after they receive the result(27.6%), 2-7 days after they received the result(20.9%) in order. The most important reason why they didn't take a medical utilization was that it seemed insignificant to them(32.4%). Conclusions: In order to promote medical utilization of low-income population, health education for abnormal result and its management would be necessary to family member as well as person with abnormal result. And follow-up management program for person with abnormal result through health examination such as home-visit health care would be necessary.

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A Study on Reputation as Corporate Asset (기업자산으로서의 기업명성가치 연구: 국내 4개 기업 슈퍼브랜드와 기업명성, 미디어 이용간 관련성을 중심으로)

  • Lee, Cheol-Han;Cha, Hee-Won
    • Korean journal of communication and information
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    • v.30
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    • pp.203-237
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    • 2005
  • The purpose of this study is to find a model that can measure the public relations programs based on the assumption that the public relations should aim to lift the corporate reputation. It is a trend that corporate's activities are to be measured from the standpoint of cost-benefit efficiency. However, public relations fields in Korea is left behind this trend because the fields lack in sophisticated model. In order to fill this gap, the researchers introduce the reputation measurement model that can calculate individual corporate public relations programs. In addition, this reputation model Is applied to Korean companies with the expectation of producing a PR index which ran be used to measure the reputation as corporate asset, or superbrand. This study examines the effects of superbrand on consumers according to the media use. Based on the expert group interviews and surveys on consumers, the factors of reputation are drawn. These factors contribute to find reputation model and measurement index which are again applied to measure the Korean companies' public relations programs. Using superbrand as dependent variables and managing abilities, corporate responsibility, corporate communication, and product/employee quality, this study seeks to find which factor specifically attribute to lift corporate reputation. Results show that each factor influences the corporate reputation positively. In addition, the researchers find that media use is moderately related to the superbrand building process in cognitive dimension.

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The Effect of Positioning with Mechanically Ventilatory Acute Respitatory Failure Patients on Arterial Oxygen Partial Pressure and Alveolar-arterial Oxygen tension (인공호흡기를 부착한 급성 호흡부전 환자에서 폐병변 부위에 따른 체위적용이 동맥혈 가스분압 및 폐포동맥간 산소 분압차에 미치는 영향)

  • Hwang, Hee Joung;Park, Hye Ja
    • Korean Journal of Adult Nursing
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    • v.12 no.2
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    • pp.234-244
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    • 2000
  • It is widely recognized that manipulation of body position takes advantage of the influences of gravity for improving oxygenation. The study aims to determine the effects of positioning(supine, prone, right lateral decubitus and left lateral decubitus positions) applied to the mechanically ventilatory acute respiratory failure patients on arterial oxygen partial pressure($PaO_2$), alveolar arterial oxygen tension difference($AaDO_2$), mean aterial pressure, peak inspiratory pressure and plateau pressure. Thirty two acute respiratory failure patients admitted to the medical intensive care unit at Kangnam St. Mary's Hospital, The Catholic University of Korea from March 1997 to January 1998, were divided into three groups by radiographic evidence of unilateral or bilateral lung disease. In group 1 with dominant right lung disease were twelve subjects, group 2 with dominant left lung disease had eight subjects and group 3 had twelve subjects with bilateral lung disease. The variables were measured in 30 minutes after each position of supine, prone, good lung down lateral decubitus and sick lung down lateral decubitus position. The position order was done at random by Latin squre design. The results are as follows; 1) With group 1 patients, the $PaO_2$ in the left lateral decubitus and prone position were $126.8{\pm}30.8$ mmHg and $106.7{\pm}36.8$ mmHg, respectively(p=0.0001). 2) With group 2 patients, the $PaO_2$ in the prone and the right lateral decubitus position were $121.7{\pm}44.7$ mmHg and $118.5{\pm}31.7$ mmHg, respectively (p=0.0018). 3) With group 3 patients, the $PaO_2$ was $143.6{\pm}36.6$ mmHg in the prone position (p=0.0001). 4) With group 1 patients, the $AaDO_2$ in the left lateral decubitus and the right lateral decubitus position were $178.1{\pm}29.7$ mmHg and $233.1{\pm}24.4$ mmHg, respectively(p=0.0001). 5) With group 2 patients, the $AaDO_2$ in the prone and the left lateral decubitus postion were $184.0{\pm}39.5$ mmHg and $231.0{\pm}23.9$ mmHg, respectively(p=0.0019). 6) With group 3 patients, the $AaDO_2$ in the prone and the supine postion were $377.1{\pm}35.6$ mmHg and $435.7{\pm}13.1$ mmHg, respectively (p=0.0001). 7) There were no differences among the mean arterial pressure, peak inspiratory pressure and plateau pressure for each of the supine, prone, left lateral decubitus and right lateral decubitus position. The results suggest that oxygenation may improve in mechanically ventilatory patients with unilateral lung disease when the position is good lung dependent and prone, and patients with bilateral lung disease when the position is prone without any effects on the mean arterial pressure and airway pressure. It is suggested that body positions improve ventilation/perfusion matching and oxygenation need to be specified in patient care plans.

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An Analysis of the Impact of Entrepreneurial Activities in Busan on Regional Economic Growth and Reduction of Unemployment Rate (부산지역 창업활동이 지역경제 성장과 실업률 저감에 미치는 영향 분석)

  • Kim, Ji Young;Lee, Ye Lim
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.11 no.6
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    • pp.111-122
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    • 2016
  • Support and efforts are being strengthened at the national level for entrepreneurial activities that are expected to revitalize our economy. Generally, according to the previous studies, it is known that entrepreneurship positively affects economic growth and the reduction of unemployment rate through employment creation. The analysis of the impact of entrepreneurial activities on economic growth and job creation is mainly based on national comparative analysis. In this paper, however, the impact of start-up activities in the Busan metropolitan city on regional economic growth and employment improvement. In this study, the dummy variables were assigned to firms within three years, five years, and ten years after start-up according to the period since the start-up of the firm. As a result of the empirical analysis, the value of dummy variable of the start - up firms was found to be significant in the analysis of the sales growth rate as the dependent variable according to the preceding study by Evans(1987). Therefore, it can be seen that the growth rate of the start - up company is higher than that of the other companies and it is positive for the regional economic growth. In addition, the coefficient of the dummy variable decreases from the enterprise analysis to the latter within three years, five years, and ten years after the start-up, and confirms that the coefficient of the firm's start-up years has a negative value. I could see more clearly. On the other hand, in the analysis of the effect of start-up firms on unemployment rate reduction, the growth rate of regular workers was higher than that of other firms. This suggests that it positively affects the reduction of the unemployment rate in the region. In addition, in the dynamic analysis using the Almon estimation formula and the Koyck model, the effect of log-transformed net start-up firms on the growth rate of new workers is very significant. As a result of the above model, It is reaffirmed that start-up activity has a positive effect on employment growth.

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Optimal hot water extraction conditions of fermented Polygonum multiflorum root by Lentinula edodes pegler mycelials using response surface methodology (반응표면 분석법에 의한 표고균사체발효 적하수오 열수 추출조건의 최적화)

  • Oh, Junseok;Hong, Jae-Heoi;Park, Tae-Young;Shin, Ji-eun;Kim, Kyung-Je;Jin, Seong-Woo;Ban, Seung-Eon;Koh, Young-Woo;Im, Seung-Bin;Seo, Kyoung-Sun
    • Journal of Mushroom
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    • v.16 no.1
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    • pp.22-30
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    • 2018
  • This study was performed to determine optimal extraction conditions of fermented Polygonum multiflorum root by Lentinula edodes (JMI10079) Pegler mycelials using response surface methodology. The independent factors were extraction temperature (X1: $40-100^{\circ}C$), extraction time (X2: 2-10 hrs.), and the ratio of water to sample (X3: 33-100 mg/mL). Their effects were assessed on dependent variables of the extract properties, which included soluble solid contents (Y1), $^{\circ}Brix$ of sample extract (Y2), total polyphenol content (Y3), total flavonoid content (Y4), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation scavenging activity (Y5) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (Y6). The experimental data obtained were fit to a second-order polynomial equation. The optimal extraction conditions for fermented P. multiflorum root were: X1: $91.22^{\circ}C$, X2: 7.72 hrs, and X3: 39.71 mg/mL.

The Study on the Influence of Selection Characteristics of Franchise System, business possibility, Communication, Moral Hazard on Franchisee's Perceived Risk, and Recontracting Intention in the Food Service Franchise Industry (외식 프랜차이저의 사업성, 커뮤니케이션, 모럴해저드가 프랜차이지의 위험지각과 재계약의도에 미치는 영향)

  • Yu, Jong-Pil;Lee, In-Ho
    • Journal of Distribution Research
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    • v.16 no.1
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    • pp.1-27
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    • 2011
  • I. Introduction: This study is to examine the structural relationships among exogenous variable (preliminary and post-support, franchisee's perceived business possibility, communication, moral hazard), the mediated variables(satisfaction, perceived risk, trust) and dependent variable(recontracting intention) in the food service franchise industry context. More specifically, this study has considered some realistic characteristics factors influencing satisfaction, perceived risk and trust between franchisors and franchisees and their further recontracting intention from the perspective of a practical approach. In this study, 437 data has been collected and used for the SPSS and AMOS analysis. The data were analyzed with structural equation modeling. Since the result of the overall model analysis demonstrated a good fit, we could further analyze our data. II. Research Model: This study is to examine the structural relationships among preliminary and post-support by franchisor, franchisee's perceived business possibility, and communication, moral hazard, has on effect on franchisee's satisfaction, perceived risk, trust and recontracting intention in the food service franchise industry context. Hypotheses are as following (Stern & EL-Ansary 1988; Oliver, 1997;Kee & Knox, 1970; Moorman, Deshpande & Zaltman, 1993; Perron, 1998; Zaheer, McEvily, Perrone, 1998). III. Result and Implication: We examined franchisee who have food service stores for samples of this study. The data were analyzed with structural equation modeling using path analysis. The result of the overall model analysis appeared as following: ${\chi}^2$ = 61.578 (d.f.=9, p<0.01), CFI =.990, GFI =.973, AGFI =.863, RMR =.019, RMSEA= .116, NFI = .988, TLI = .959. The findings can be summarized as follows: First, preliminary and post support of franchisor, perceived business possibility and communication positively influence to franchisee's satisfaction. Second, moral hazard of franchisor has negatively influence to franchisee's satisfaction and positively influence to perceived risk. Third, franchisee's satisfaction and trust has positively influence to recontracting intention. Fourth, franchisee's perceived risk has negatively influence to trust and recontracting intention. We can concluded that franchisor's preliminary and post support of franchisor, perceived business possibility and communication may be considered as the important factors influence to franchisee's satisfaction. Moral hazard has become a focused issue in franchise industry. Finally, the managerial implication has been stated as followings: First, in the process of building a systematic industry support franchise system and developing a creative business model, franchisee's stable profitability should be considered as the first important factor. The franchisee's trust to franchise may become a dominant factor that influence the business expansion of franchisor. Second, franchisor should communication with their franchisees and deal with the realistic difficulties faced by them with an effort. Third, the franchisor should achieve a synergy effect by utilizing the win-win strategy. The moral hazard strategy that achieving the profit through franchisee's damage will not be inadvisable to franchisor. Then the long-term oriented development and profitability can be maintained. To do so, the franchise industry may break away from the traditional business structure to improve management transparency and competitiveness on investment and organizational changing management. The conflict between franchisor and franchisee also can be reduced and big success can be achieved in the franchise industry.

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A Study on the Development of a Simulation Model for Predicting Soil Moisture Content and Scheduling Irrigation (토양수분함량 예측 및 계획관개 모의 모형 개발에 관한 연구(I))

  • 김철회;고재군
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.19 no.1
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    • pp.4279-4295
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    • 1977
  • Two types of model were established in order to product the soil moisture content by which information on irrigation could be obtained. Model-I was to represent the soil moisture depletion and was established based on the concept of water balance in a given soil profile. Model-II was a mathematical model derived from the analysis of soil moisture variation curves which were drawn from the observed data. In establishing the Model-I, the method and procedure to estimate parameters for the determination of the variables such as evapotranspirations, effective rainfalls, and drainage amounts were discussed. Empirical equations representing soil moisture variation curves were derived from the observed data as the Model-II. The procedure for forecasting timing and amounts of irrigation under the given soil moisture content was discussed. The established models were checked by comparing the observed data with those predicted by the model. Obtained results are summarized as follows: 1. As a water balance model of a given soil profile, the soil moisture depletion D, could be represented as the equation(2). 2. Among the various empirical formulae for potential evapotranspiration (Etp), Penman's formula was best fit to the data observed with the evaporation pans and tanks in Suweon area. High degree of positive correlation between Penman's predicted data and observed data with a large evaporation pan was confirmed. and the regression enquation was Y=0.7436X+17.2918, where Y represents evaporation rate from large evaporation pan, in mm/10days, and X represents potential evapotranspiration rate estimated by use of Penman's formula. 3. Evapotranspiration, Et, could be estimated from the potential evapotranspiration, Etp, by introducing the consumptive use coefficient, Kc, which was repre sensed by the following relationship: Kc=Kco$.$Ka+Ks‥‥‥(Eq. 6) where Kco : crop coefficient Ka : coefficient depending on the soil moisture content Ks : correction coefficient a. Crop coefficient. Kco. Crop coefficients of barley, bean, and wheat for each growth stage were found to be dependent on the crop. b. Coefficient depending on the soil moisture content, Ka. The values of Ka for clay loam, sandy loam, and loamy sand revealed a similar tendency to those of Pierce type. c. Correction coefficent, Ks. Following relationships were established to estimate Ks values: Ks=Kc-Kco$.$Ka, where Ks=0 if Kc,=Kco$.$K0$\geq$1.0, otherwise Ks=1-Kco$.$Ka 4. Effective rainfall, Re, was estimated by using following relationships : Re=D, if R-D$\geq$0, otherwise, Re=R 5. The difference between rainfall, R, and the soil moisture depletion D, was taken as drainage amount, Wd. {{{{D= SUM from { {i }=1} to n (Et-Re-I+Wd)}}}} if Wd=0, otherwise, {{{{D= SUM from { {i }=tf} to n (Et-Re-I+Wd)}}}} where tf=2∼3 days. 6. The curves and their corresponding empirical equations for the variation of soil moisture depending on the soil types, soil depths are shown on Fig. 8 (a,b.c,d). The general mathematical model on soil moisture variation depending on seasons, weather, and soil types were as follow: {{{{SMC= SUM ( { C}_{i }Exp( { - lambda }_{i } { t}_{i } )+ { Re}_{i } - { Excess}_{i } )}}}} where SMC : soil moisture content C : constant depending on an initial soil moisture content $\lambda$ : constant depending on season t : time Re : effective rainfall Excess : drainage and excess soil moisture other than drainage. The values of $\lambda$ are shown on Table 1. 7. The timing and amount of irrigation could be predicted by the equation (9-a) and (9-b,c), respectively. 8. Under the given conditions, the model for scheduling irrigation was completed. Fig. 9 show computer flow charts of the model. a. To estimate a potential evapotranspiration, Penman's equation was used if a complete observed meteorological data were available, and Jensen-Haise's equation was used if a forecasted meteorological data were available, However none of the observed or forecasted data were available, the equation (15) was used. b. As an input time data, a crop carlender was used, which was made based on the time when the growth stage of the crop shows it's maximum effective leaf coverage. 9. For the purpose of validation of the models, observed data of soil moiture content under various conditions from May, 1975 to July, 1975 were compared to the data predicted by Model-I and Model-II. Model-I shows the relative error of 4.6 to 14.3 percent which is an acceptable range of error in view of engineering purpose. Model-II shows 3 to 16.7 percent of relative error which is a little larger than the one from the Model-I. 10. Comparing two models, the followings are concluded: Model-I established on the theoretical background can predict with a satisfiable reliability far practical use provided that forecasted meteorological data are available. On the other hand, Model-II was superior to Model-I in it's simplicity, but it needs long period and wide scope of observed data to predict acceptable soil moisture content. Further studies are needed on the Model-II to make it acceptable in practical use.

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