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Estimation of Food Commodity Intakes from the Korea National Health and Nutrition Examination Survey Databases: With Priority Given to Intake of Perilla Leaf (국민건강영양조사 자료를 이용한 식품 섭취량 산출 방법 개발: 들깻잎 섭취량을 중심으로)

  • Kim, Seung Won;Jung, Junho;Lee, Joong-Keun;Woo, Hee Dong;Im, Moo-Hyeog;Park, Young Sig;Ko, Sanghoon
    • Food Engineering Progress
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    • v.14 no.4
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    • pp.307-315
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    • 2010
  • The safety and security of food supply should be one of the primary responsibilities of any government. Estimation of nation's food commodity intakes is important to control the potential risks in food systems since food hazards are often associated with quality and safety of food commodities. The food intake databases provided by Korea National Health and Nutrition Examination Survey (KNHANES) are good resources to estimate the demographic data of intakes of various food commodities. A limitation of the KNHANES databases, however, is that the food intakes surveyed are not based on commodities but ingredients and their mixtures. In this study, reasonable calculation strategies were applied to convert the food intakes of the ingredients mixtures from the KNHANES into food commodity intakes. For example, Perilla leaf consumed with meat, raw fish, and etc. in Korean diets was used to estimate its Korean intakes and develop algorithms for demographic analysis. Koreans have consumed raw, blanched, steamed, and canned perilla leaf products. The average daily intakes of the perilla leaf were analyzed demographically, for examples, the intakes by gender, age, and etc. The average daily intakes of total perilla leaf were 2.03${\pm}$0.27 g in 1998, 2.11${\pm}$0.26 g in 2001, 2.29${\pm}$0.27 g in 2005, 2.75${\pm}$0.35 g in 2007, and 2.27${\pm}$0.20 g in 2008. Generally, people equal to or over 20 years of age have shown higher perilla leaf intakes than people below 20. This study would be contributed to the estimation of intakes of possible chemical contaminants such as residual pesticides and subsequent analysis for their potential risk.

Effects of Visiting Prehabilitation Program against Functional Decline in the Frail Elderly: A Prospective Randomized Community Trial (허약노인을 위한 방문재활 프로그램의 장애발생예방 효과에 대한 연구)

  • Kim, Chang-O;Lee, Heeyeon;Ho, Seung Hee;Park, Hyunsuk;Park, Chulwoo
    • 한국노년학
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    • v.30 no.4
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    • pp.1293-1309
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    • 2010
  • This study is aimed to evaluate the effects of community-based prehabilitation program developed to prevent functional decline in the frail elderly and to provide a basis to practically operate this program in the public health care service. From March to August 2009, 110 frail elderly people were recruited among the registered participants of the home visit program in Korea to perform a prospective randomized community trial. We randomly assigned these people into two groups. One group (n=50) participated in the visiting prehabilitation program for 3 months focusing on improving their muscle strength of upper and lower limbs, walking ability, and balancing. The other group (n=60) underwent our visiting fall prevention program for control. To assess the effectiveness of prehabilitation program, physical functioning (PF) and short physical performance battery (SPPB) were measured for the primary outcomes and also some other indicators: exercise performance, nutritional status, emotional functioning, experience of admission, and events of fall. As a result, significant improvements of geriatric functional status were noticed among the participants. After 3 months, PF increased by 1.3 ± 3.8 points in prehabilitation group and decreased by 1.1 ± 5.4 points in controls (p=.020). SPPB improved by 2.4 ± 2.0 points in prehabilitation group and increased only 0.3 ± 1.5 points in controls (p<.001). Significant effects were also shown in their exercise performance tests and emotional status, the number of multiple falls, and the experience of functional decline after the fall (p .002-.038). Visiting prehabilitation program is safe and effective program for frail older adults. Thus, it is strongly recommended to universally adopt this program to prevent functional decline in the frail elderly.

Theoretical Study on Modeling Success Factors of Overseas Agricultural Startups (해외 농업스타트업 성공요인 모델링에 관한 이론적 고찰)

  • Jinhwan, Park;Sangsoon, Kim
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.18 no.1
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    • pp.85-106
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    • 2023
  • This study reviewed and derived the success factors of overseas agricultural startups and studied their integrated research model. Agricultural startups and general startups have in common that poor resources and infrastructure exist from a resource-based perspective after startup, but a differentiated approach from general startups is required due to the nature of the primary industry of agriculture. In this study, we approach the company internal factors (human resources/vision/distribution network capacity/capital capacity/cultivated crops/physical resources/farming technology, etc.) and external factors (agricultural infrastructure/laws/regulations/relationship with surrounding society, etc.) We tried to build a research model that can be integrated by focusing on various existing research models, success factors, and entrepreneurship. Through this, it is intended to present an integrated model that is practically helpful to business performance to entrepreneurs, business-related persons, and researchers who need an integrated understanding of agricultural startups at home and abroad. made for purpose In this paper, a standard model was established through three types (existing agricultural startup, small and medium-sized business startup, multinational company, and comprehensive approach) according to size and characteristics for modeling agricultural startup success factors. Through this, a total of 9 success factors (agricultural management, external environment, manager/founder characteristics, corporate identity, business management, organizational culture, infrastructure, commercialization capability, and sustainable growth) were derived. The implication of this study is that the success factors of agricultural startups were comprehensively presented based on 'entrepreneurship' for various domestic and foreign agricultural startup cases. By confirming the systematic categorization, a standard model for future agricultural startup success factors was presented, and as a result, a foundation was presented for systematic research and practical effectiveness of related research in the future.

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The Risk of Onset of the Illnesses Based on Gender, Age, and Monthly Income;Focusing on cancer, hypertension, stroke, diabetes, arthritis, cardiac disorders (성별, 연령별, 월소득차이에 따른 질병발생의 위험성 차이연구;암, 고혈압, 중풍, 당뇨병, 관절염, 심장병을 중심으로)

  • Lee, Jun-Oh;Kim, Se-Jin;Lee, Sun-Dong
    • Journal of Society of Preventive Korean Medicine
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    • v.12 no.1
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    • pp.19-48
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    • 2008
  • In order to verify the risk of onset of the illnesses based on gender, age, and monthly income 1,739 subjects from Hongcheon county, Gangwon province were selected. Questionnaire on demographic sociology, health condition, existence of illnesses(cancer, hypertension, stroke, diabetes, arthritis, cardiac disorders), and usage of public health services was surveyed from October 1, 2006 to October 20, 2006. Following conclusions were reached on the basis of the questionnaire : - For demographic sociological peculiarities, gender, age, occupation, and education level were evenly distributed. Most were under normal marriage(67.38%), health insurance(86.39%), 494(36.0%) individuals with less than monthly income of 1 million won, 494(36.0%) individuals with monthly income between 1 and 2 million won, 219(16.0%) with monthly income between 2 and 3 million won, and 164(12.0%) individuals with more than 3 million won, thus showing relatively low income. - For health status, 1,199(70.28%) individuals are non-smokers, 209(45.63%) individuals smoke $10{\sim}20$ cigarettes a day, 754(44.02%) individuals exercise less than twice a week are the major sector of the population. 1,518(88.10%) individuals have regular checkup more than once and 1,131(65.49%) stated their health condition less than average. - For comparison of existence of illnesses between genders, there was no statistical significance on cancer, stroke, and diabetes. But statistical significance was shown on hypertension(P value 0.025), arthritis(P value 0.000), and cardiac disorders(P value 0.016). Statistical significance was seen in the age comparison, and OR(confidence interval) drastically increased with increase in age. - There was no difference between the primary health clinic(P value 0.000), most visited clinic(P value 0.000), selection criteria(P value 0.000), and satisfaction on efficacy(P value 0.000). There was a tendency preferring hospital than public health center with increase in income. - For correlation between the existence of illnesses among different income levels, except for cancer(P value 0.172), statistical significance was seen in hypertension(P value 0.000), stroke(P value 0.003), diabetes (P value 0.001), arthritis(P value 0.000), and cardiac disorders(P value 0.000). The number of individuals suffering from illnesses and ratio all decreased for all illnesses with increase in income. - After adjusting confounding factors(gender, age, income, marriage, occupation, education) and male (1) as the standard, OR (confidence interval) of cancer, hypertension, stroke, diabetes, arthritis, cardiac disorders were 0.47(0.11${\sim}$2.05), 1.27(0.89${\sim}$1.81), 0.58(0.21${\sim}$1.59), 0.71(0.41${\sim}$1.23), 1.79(1.34${\sim}$2.39, P<0.01), and 1.46(0.72${\sim}$2.96), respectively. Risk of arthritis is significantly high in female and 20's (1) as the standard, OR(confidence interval) of cancer, hypertension, stroke, diabetes, arthritis, cardiac disorders were 1.01(0.96${\sim}$1.07), 1.06(1.04${\sim}$1.07, P<0.01), 1.05(1.01${\sim}$1.10, P<0.01), 1.06(1.03${\sim}$1.08, P<0.01), 1.05(1.03${\sim}$1.06, P<0.01), and 1.06(1.04${\sim}$1.09, P<0.01), respectively. Risk of onset for illnesses significantly increased with yearly aging except for cancer. - For comparison between monthly income after adjusting confounding factors(gender, age, income, marriage, occupation, education), with less than 1 million won (1) as the standard, OR(confidence interval) of cancer for 1 to 2 million won, 2 to 3 million won, and more than 3 million won were 0.23(0.03${\sim}$2.16), 2.53(0.41${\sim}$15.43), and 1.73(0.15${\sim}$19.50), respectively. OR(confidence interval) of hypertension were 1.12(0.76 ${\sim}$1.66), 0.68(0.34${\sim}$1.34), and 2.04(1.08${\sim}$3.86, P<0.01), respectively. OR(confidence interval) of stroke were 0.96(0.30${\sim}$3.08) for 1 to 2 million won, and 0.80(0.08${\sim}$8.46) for 2 to 3 million won. OR(confidence interval) of diabetes were 0.73(0.38${\sim}$1.38), 0.65(0.24${\sim}$1.71), and 0.69(0.24${\sim}$2.01), respectively. The values were 0.76(0.55${\sim}$1.03), 1.14(0.75${\sim}$1.73), and 0.90(0.56${\sim}$1.46), respectively for arthritis. OR(confidence interval) of cardiac disorders were 1.15(0.53${\sim}$2.48), 0.63(0.13${\sim}$3.12), and 1.20(0.28${\sim}$5.14), respectively. Risks of cancer, hypertension, stroke, diabetes, arthritis, and cardiac disorders were dependent of monthly income, and stroke and diabetes decreased with increase in income. Summarizing above data, arthritis was significantly higher in women and increase in age by each year brought significant increase in the chance of onset in hypertension, stroke, diabetes, arthritis, and cardiac disorders except for cancer. Stroke and diabetes decreased with increase in income. Above findings can be applied and reflected in public health policies at the national level, and it can also be applied at the personal level for individual health maintenance and prevention.

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Analysis of Metadata Standards of Record Management for Metadata Interoperability From the viewpoint of the Task model and 5W1H (메타데이터 상호운용성을 위한 기록관리 메타데이터 표준 분석 5W1H와 태스크 모델의 관점에서)

  • Baek, Jae-Eun;Sugimoto, Shigeo
    • The Korean Journal of Archival Studies
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    • no.32
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    • pp.127-176
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    • 2012
  • Metadata is well recognized as one of the foundational factors in archiving and long-term preservation of digital resources. There are several metadata standards for records management, archives and preservation, e.g. ISAD(G), EAD, AGRkMs, PREMIS, and OAIS. Consideration is important in selecting appropriate metadata standards in order to design metadata schema that meet the requirements of a particular archival system. Interoperability of metadata with other systems should be considered in schema design. In our previous research, we have presented a feature analysis of metadata standards by identifying the primary resource lifecycle stages where each standard is applied. We have clarified that any single metadata standard cannot cover the whole records lifecycle for archiving and preservation. Through this feature analysis, we analyzed the features of metadata in the whole records lifecycle, and we clarified the relationships between the metadata standards and the stages of the lifecycle. In the previous study, more detailed analysis was left for future study. This paper proposes to analyze the metadata schemas from the viewpoint of tasks performed in the lifecycle. Metadata schemas are primarily defined to describe properties of a resource in accordance with the purposes of description, e.g. finding aids, records management, preservation and so forth. In other words, the metadata standards are resource- and purpose-centric, and the resource lifecycle is not explicitly reflected in the standards. There are no systematic methods for mapping between different metadata standards in accordance with the lifecycle. This paper proposes a method for mapping between metadata standards based on the tasks contained in the resource lifecycle. We first propose a Task Model to clarify tasks applied to resources in each stage of the lifecycle. This model is created as a task-centric model to identify features of metadata standards and to create mappings among elements of those standards. It is important to categorize the elements in order to limit the semantic scope of mapping among elements and decrease the number of combinations of elements for mapping. This paper proposes to use 5W1H (Who, What, Why, When, Where, How) model to categorize the elements. 5W1H categories are generally used for describing events, e.g. news articles. As performing a task on a resource causes an event and metadata elements are used in the event, we consider that the 5W1H categories are adequate to categorize the elements. By using these categories, we determine the features of every element of metadata standards which are AGLS, AGRkMS, PREMIS, EAD, OAIS and an attribute set extracted from DPC decision flow. Then, we perform the element mapping between the standards, and find the relationships between the standards. In this study, we defined a set of terms for each of 5W1H categories, which typically appear in the definition of an element, and used those terms to categorize the elements. For example, if the definition of an element includes the terms such as person and organization that mean a subject which contribute to create, modify a resource the element is categorized into the Who category. A single element can be categorized into one or more 5W1H categories. Thus, we categorized every element of the metadata standards using the 5W1H model, and then, we carried out mapping among the elements in each category. We conclude that the Task Model provides a new viewpoint for metadata schemas and is useful to help us understand the features of metadata standards for records management and archives. The 5W1H model, which is defined based on the Task Model, provides us a core set of categories to semantically classify metadata elements from the viewpoint of an event caused by a task.

The Long-term Follow-up Study of Therapeutic Effects of 8 French Catheter for Spontaneous Pneumothorax (자연 기흉의 치료에서 8 French 도관삽입의 치료 효과에 대한 장기적 관찰)

  • Shin, Jong-Wook;Lee, Byoung-Hoon;An, Chang-Hyeok;Choi, Jae-Sun;Yoo, Jee-Hoon;Lim, Seong-Yong;Kang, Yoon-Jung;Koh, Hyung-Ki;Kim, Jae-Yeol;Na, Moon-Jun;Park, In-Won;Sobn, Dong-Suep;Choi, Byoung-Whui;Hue, Sung-Ho
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.5
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    • pp.1094-1104
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    • 1997
  • Background : Spontaneous pneumothoraces(SP) are divided into primary spontaneous pneumothoraces (PSP) which develop in healthy individuals without underlying pulmonary disorders and secondary spontaneous pneumothoraces(SSP) which occur in those who have underlying disorders such as tuberculosis or chronic obstructive lung diseases. Yet there is no established standard therapeutic approach to this disorder, i.e., from the spectrum of noninvasive treatment such as clinical observation with or without oxygen therapy, to aggressively invasive thoracoscopic bullectomy or open thoracotomy. Although chest tube thoracostomy has been most widely used, the patients should overcome pain in the initiation of tube insertion or during indwelling it potential infection and subcutaneous emphysema. Thus smaller-caliber tube has been challenged for the treatment of pneumothorax. Previously, we studied the therapeutic efficacy of 8 French catheter for spontaneous pneumothorax. But there has been few data for effectiveness of small-caliber catheterization in comparison with that of chest tube. In this study, we intended to observe the long-term effectiveness of 8 French catheter for the treatment of spontaneous pneumothoraces in comparison with that of chest tube thoracostomy. Method : From January, 1990 to January, 1996, sixty two patients with spontaneous pneumothoraces treated at Chung-Ang University Hospital were reviewed retrospectively. The patients were sub-divided into a group treated with 8 French catheter(n=23) and the other one with chest tube insertion(n=39). The clinical data were reviewed(age, sex, underlying pulmonary disorders, past history of pneumothorax, size of pneumothorax, follow-up period). And therapeutic effect of two groups was compared by treatment duration(duration of indwelling catheter or tube), treatment-associated complications and recurrence rate. Results : The follow-up period(median) of 8 French catheter group and chest tube group was 28 and 22 months, which had no statistical significance. Ther was no statistically significant difference of clinical characteristics between two groups with SP, PSP, SSP. The indwelling time of 8 French catheter group was $6.2{\pm}3.8$ days, which was significantly shorter than that of chest tube group in SP, $9.1{\pm}7.5$ days(p=0.047). In comparison of treatment-related complication in PSP, 8 French catheter group as 6.25% of complication showed lower tendency than the other group as 23.8% (p=0.041 ; one-tailed, p=0.053; two-tailed). The recurrence rate in each group of SP was 17.4%, 10.3%, which did not show any statistically significant difference. Conclusion : Treatment with 8 French catheter resulted in shorter indwelling time in sponteous pneumothorax, and lower incidence of treatment-related complication in primary spontaneous pneumothorax. And the recurrence rate in each of treatment group showed no statistically significant difference. So, we can recommend the 8 French small-caliber catheter for the initial therapy for spontaneous pneumothorax for the replacement of conventional chest tube thoracostomy. But further prospective study with more subjects of spontaneous pneumothorax will be needed for the evaluation of effectiveness of 8 French cateter.

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Second allogeneic hematopoietic stem cell transplantation in children to overcome graft failure or relapse after initial transplant (조혈모세포이식 후 생착 실패나 재발한 소아환자에서 2차 이식의 의의)

  • Kim, Dong-Yeon;Kim, Do Kyun;Kim, Soo Young;Kim, Seok Joo;Han, Dong Gyun;Baek, Hee Jo;Kook, Hoon;Hwang, Tai-Ju
    • Clinical and Experimental Pediatrics
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    • v.49 no.12
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    • pp.1329-1339
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    • 2006
  • Purpose : Failure of hematopoietic stem cell transplantation(HSCT) may be encountered in practice because of either relapse of the malignancy or dysfunction of the graft. Second HSCT may be the only option for some patients whose initial HSCT failed. Methods : From May, 1991 to December, 2004, 115 HSCTs were performed at the Pediatric Blood & Marrow Transplantation Center, Chonnam National University. This study was a retrospective analysis of the medical records of 15 patients who received the second HSCT after initial graft. Results : Among eight patients with nonmalignant diseases, two patients underwent the second HSCT because of primary graft failure and five because of late graft rejection. The remaining Fanconi anemia patient was re-transplanted due to development of AML. Two patients died and one experienced primary graft failure, but is still alive. The Kaplan-Meier 5-year overall survival rate was 75 percent and the disease free survival rate was 62.5 percent in nonmalignant diseases. All malignant patients underwent second transplants because of relapses. Four died of relapse and one of treatment-related complications. The Kaplan-Meier 2-year overall and event free survival rate was 28.6 percent each in malignant diseases. Conclusion : Second HSCT for graft dysfunction of nonmalignant disease seems to be feasible and should be considered as a standard practice. The relapse of malignant diseases remains a big obstacle even after the second HSCT, although a small portion of patients might be salvaged. Further investigation of novel therapeutic strategies, as well an the understanding of the biology should be explored.

A Survey of Nutritional Status on Pre-School Children in Korea (학영기전아동(學齡期前兒童)의 영양실태조사(營養實態調査))

  • Ju, Jin-Soon;Oh, Seoung-Ho
    • Journal of Nutrition and Health
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    • v.9 no.2
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    • pp.68-86
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    • 1976
  • The primary purpose of this study is to evaluate the correct nutritional status on pre-school children in Korea. Furthermore, it made an attempt to find and define nutrional problems, and assist in establishment on their nutritional improvement plan. For this, food intake and health condition (physical, clinical, biochemical and parasitological) survey on 109 Pre-school children in both sexes, randomly selected from Yang-Gu area in Gang-Won province and Rea-ju area in Kyong-gy Province, were conducted by means of three-day records, during the two periods of Spring and Fall season in 1975. The results obtained are summerized as follows: 1. The food intake; Average food intake of the subjects per day were $508{\sim}647g$ ($83{\sim}91%$ in vegetable foods and $5.5{\sim}11.7%$ in animal foods) in Yang-gu area, and $587{\sim}698g$ ($88{\sim}89%$ in vegetable foods and $6.3{\sim}7.6%$ in animal foods) in Rea-ju area. 2. The intake of energy and nutrients; a) Calory intake. Average energy intake of subjects per day in Yang-gu area$(1120{\sim}1415kcal)$ were all lower than the Korean Recommended Dietary Allowances (RDA) in either Spring and Fall survey, whereas the subjects in Rea-ju area were lower intake $(1213{\sim}1418kcal)$ than the RDA in the Spring but higher intake$(1516{\sim}1755kcal)$ than the RDA in the Fall, and the average intake were similar level with that of RDA. b) Protein intake. Average protein intake of the subjects per day in Yang-gu area $(33{\sim}43g)$ girl subjects in Rea-ju area $(35{\sim}39g)$ were lower than the RDA in either Spring and Fall survey, whereas the boy subjects in Rea-ju area$(36{\sim}38g)$ were lower in Spring and higher $(49{\sim}57g)$ in the Fall than that of the RDA, but the average $(43{\sim}47g)$ were similar level with the RDA. The protein intake from animal sources in all subjects were much lower $(5.5{\sim}11.7\;of\;total\;protein)$ than the RDA. c) Fat intake. Average fat intake were very lower in all subjects of both area $(14{\sim}24g\;in\;Yang-gu,\;10{\sim}12g\;in\;Rea-ju)$ than that of RDA which is recommended $12{\sim}14%$ of total energy to be supplied from fat. d) Calcium intake. Average calcium intake were very low in all subjects of both area $(264{\sim}355mg\;in\;Yang-gu\;and\;283{\sim}429mg\;in\;Rea-ju)$, especially, these in Spring were about a half level of the RDA, and it was much increased in the Fall due to increased intake of milk, but it was still not enough than the RDA. e) Vitamin A intake. Average intake of V.A ($703{\sim}1465\;IU$ in Ynag-gu and $750{\sim}1521\;IU$ in Rea-ju) were also lower than the RDA, moreover their V-A sources were mainly vegetable, so that the V-A supply might be critical one for the subjected. f) Riboflavin intake. Average riboflavin intake on all subjects in both area except boys in Rea-ju area in Fall, were very lower than the RDA. 3. The physical status; a) Average weight and height of boys aged 4 and 5 in Yang-gu area and girls of aged 5 in Rea-ju area were lower than those of Korean Standard of 1967 report, but those by age of girls in Yang-gu area and boys in Rea-ju area were a little heigher than the Korean Standard. It is, hower, present Korean standard of physical status might be somehow heigher than the 1967, since the socio-economical situation has been much improved during past a decade. So that, if one considered on this sense, the physical status of the subjects on this survey might be somehow lower than those of present Korean standard. b) Average upper arm circumference in both area were no difference each other, and their mean values of age 4, 5 and 6 in boy and girl were 15.6, 16.5, 16.4 and 15.5, 16.5, 16.4cm respectively. c) Average chest girth of boys were similar to those of Korean standard whereas the girls were smaller than the Korea standard. The average head circumference also showed similar tendency with the chest girth. 4. The clinical findings; The most popular clinical signs were angular stomatitis and dental caries, and boys had more heigher incidence then the girls. 5. The biochemical findings; a) Hemoglobin and anemia Average Hb value of boys and girls were 11.4 and 10.9g per 100 ml of blood respectively. The incidence of anemia (Hb value below 11 g/100 ml, by WHO) was increased by age, and girls had more heigher incidence than the boy (34% : 48%). The incidence of anemia in age of 4,5, and 6 in boys and girls were 28%, 41% 34%, and 33%, 50%, 49% respectively. The degree of the anemia was not severe, and the anemia of there subjects may be caused mainly low intake of better quality protein and low iron intake as well. b) Hematocrit. Average Ht value of whole subject were $39.9{\sim}41.6%$. c) Blood plasma protein. Average blood plasma protein contents of whole subjects were $6.6{\sim}7.4gm$ per 100 ml. The incidence of deficient range (<6.0g%, by ICNND) was only one girl of age 4 in yang Gu area. 6. Parasitological findgs; The most popular parasitism were asicris lumbicoides and trichocephalus trichiura, and about 2/3 of the whole subjects were suffering one or more of these parasitism.

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The Hardness Water Production By RO/NF/ED Linking Process From Deep Seawater (RO/NF/ED 연계 공정에 의한 고경도 담수 제조)

  • Moon, Deok-Soo;Kim, Kwang Soo;Gi, Ho;Choi, Mi Yeon;Jung, Hyun Ji;Kim, Hyun Ju
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.16 no.4
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    • pp.227-238
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    • 2013
  • The purpose of this study is to develop a process technology to produce high hardness drinking water which meet drinking water standard, remaining useful minerals like magnesium and calcium in the seawater desalination process while removing the sulfate ions and chloride ions. Seawater have been separated the concentrated seawater and desalted seawater by passing on Reverse Osmosis membrane (RO). Using Nano-filtration membrane (NF), We were prepared primary mineral concentrated water that sodium chloride were not removed. By the operation of electro-dialysis (ED) having ion exchange membrane, we were prepared concentrated mineral water (Mineral enriched desalted water) which the sodium chloride is removed. We have produced the high hardness water to meet the drinking water quality standards by diluting the mineral enriched desalted water with deionized water by RO. Reverse osmosis membranes (RO) can separate dissolved material and freshwater from seawater (deep seawater). The desalination water throughout the second reverse osmosis membrane was completely removed dissolved substances, which dissolved components was removed more than 99.9%, its the hardness concentration was 1 mg/L or less and its chloride concentration was 2.3 mg/L. Since the nano-filtration membrane pore size is $10^{-9}$ m, 50% of magnesium ions and calcium ions can not pass through the nano-filtration membrane, while more than 95% of sodium ions and chloride ions can pass through NF membrane. Nano-filtration membrane could be separated salt components like sodium ion and chloride ions and hardness ingredients like magnesium ions and calcium ions, but their separation was not perfect. Electric dialysis membrane system can be separated single charged ions (like sodium and chloride ions) and double charged ions (like magnesium and calcium ions) depending on its electrical conductivity. Above electrical conductivity 20mS/cm, hardness components (like magnesium and calcium ions) did not removed, on the other hand salt ingredients like sodium and chloride ions was removed continuously. Thus, we were able to concentrate hardness components (like magnesium and calcium ions) using nano-filtration membrane, also could be separated salts ingredients from the hardness concentration water using electrical dialysis membrane system. Finally, we were able to produce a highly concentrated mineral water removed chloride ions, which hardness concentration was 12,600 mg/L and chloride concentration was 2,446 mg/L. By diluting 10 times these high mineral water with secondary RO (Reverse Osmosis) desalination water, we could produce high mineral water suitable for drinking water standards, which chloride concentration was 244 mg/L at the same time hardness concentration 1,260 mg/L. Using the linked process with reverse osmosis (RO)/nano filteration (NF)/electric dialysis (ED), it could be concentrated hardness components like magnesium ions and calcium ions while at the same time removing salt ingredients like chloride ions and sodium ion without heating seawater. Thus, using only membrane as RO, NF and ED without heating seawater, it was possible to produce drinking water containing high hardness suitable for drinking water standard while reducing the energy required to evaporation.

Herbicidal Phytotoxicity under Adverse Environments and Countermeasures (불량환경하(不良環境下)에서의 제초제(除草劑) 약해(藥害)와 경감기술(輕減技術))

  • Kwon, Y.W.;Hwang, H.S.;Kang, B.H.
    • Korean Journal of Weed Science
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    • v.13 no.4
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    • pp.210-233
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    • 1993
  • The herbicide has become indispensable as much as nitrogen fertilizer in Korean agriculture from 1970 onwards. It is estimated that in 1991 more than 40 herbicides were registered for rice crop and treated to an area 1.41 times the rice acreage ; more than 30 herbicides were registered for field crops and treated to 89% of the crop area ; the treatment acreage of 3 non-selective foliar-applied herbicides reached 2,555 thousand hectares. During the last 25 years herbicides have benefited the Korean farmers substantially in labor, cost and time of farming. Any herbicide which causes crop injury in ordinary uses is not allowed to register in most country. Herbicides, however, can cause crop injury more or less when they are misused, abused or used under adverse environments. The herbicide use more than 100% of crop acreage means an increased probability of which herbicides are used wrong or under adverse situation. This is true as evidenced by that about 25% of farmers have experienced the herbicide caused crop injury more than once during last 10 years on authors' nationwide surveys in 1992 and 1993 ; one-half of the injury incidences were with crop yield loss greater than 10%. Crop injury caused by herbicide had not occurred to a serious extent in the 1960s when the herbicides fewer than 5 were used by farmers to the field less than 12% of total acreage. Farmers ascribed about 53% of the herbicidal injury incidences at their fields to their misuses such as overdose, careless or improper application, off-time application or wrong choice of the herbicide, etc. While 47% of the incidences were mainly due to adverse natural conditions. Such misuses can be reduced to a minimum through enhanced education/extension services for right uses and, although undesirable, increased farmers' experiences of phytotoxicity. The most difficult primary problem arises from lack of countermeasures for farmers to cope with various adverse environmental conditions. At present almost all the herbicides have"Do not use!" instructions on label to avoid crop injury under adverse environments. These "Do not use!" situations Include sandy, highly percolating, or infertile soils, cool water gushing paddy, poorly draining paddy, terraced paddy, too wet or dry soils, days of abnormally cool or high air temperature, etc. Meanwhile, the cultivated lands are under poor conditions : the average organic matter content ranges 2.5 to 2.8% in paddy soil and 2.0 to 2.6% in upland soil ; the canon exchange capacity ranges 8 to 12 m.e. ; approximately 43% of paddy and 56% of upland are of sandy to sandy gravel soil ; only 42% of paddy and 16% of upland fields are on flat land. The present situation would mean that about 40 to 50% of soil applied herbicides are used on the field where the label instructs "Do not use!". Yet no positive effort has been made for 25 years long by government or companies to develop countermeasures. It is a really sophisticated social problem. In the 1960s and 1970s a subside program to incoporate hillside red clayish soil into sandy paddy as well as campaign for increased application of compost to the field had been operating. Yet majority of the sandy soils remains sandy and the program and campaign had been stopped. With regard to this sandy soil problem the authors have developed a method of "split application of a herbicide onto sandy soil field". A model case study has been carried out with success and is introduced with key procedure in this paper. Climate is variable in its nature. Among the climatic components sudden fall or rise in temperature is hardly avoidable for a crop plant. Our spring air temperature fluctuates so much ; for example, the daily mean air temperature of Inchon city varied from 6.31 to $16.81^{\circ}C$ on April 20, early seeding time of crops, within${\times}$2Sd range of 30 year records. Seeding early in season means an increased liability to phytotoxicity, and this will be more evident in direct water-seeding of rice. About 20% of farmers depend on the cold underground-water pumped for rice irrigation. If the well is deep over 70m, the fresh water may be about $10^{\circ}C$ cold. The water should be warmed to about $20^{\circ}C$ before irrigation. This is not so practiced well by farmers. In addition to the forementioned adverse conditions there exist many other aspects to be amended. Among them the worst for liquid spray type herbicides is almost total lacking in proper knowledge of nozzle types and concern with even spray by the administrative, rural extension officers, company and farmers. Even not available in the market are the nozzles and sprayers appropriate for herbicides spray. Most people perceive all the pesticide sprayers same and concern much with the speed and easiness of spray, not with correct spray. There exist many points to be improved to minimize herbicidal phytotoxicity in Korea and many ways to achieve the goal. First of all it is suggested that 1) the present evaluation of a new herbicide at standard and double doses in registration trials is to be an evaluation for standard, double and triple doses to exploit the response slope in making decision for approval and recommendation of different dose for different situation on label, 2) the government is to recognize the facts and nature of the present problem to correct the present misperceptions and to develop an appropriate national program for improvement of soil conditions, spray equipment, extention manpower and services, 3) the researchers are to enhance researches on the countermeasures and 4) the herbicide makers/dealers are to correct their misperceptions and policy for sales, to develop database on the detailed use conditions of consumer one by one and to serve the consumers with direct counsel based on the database.

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