• 치위생과학회지
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• 제10권2호
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• pp.63-69
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• 2010

임상치과위생사와 학생을 대상으로 치과코디네이터에 대한 인식 및 교육 후 맡고자 하는 업무분야와 수행해야 할 업무에 대한 의견을 조사하여 치과코디네이터 교육 이수자들을 위한 업무분야의 확장과 더 심화해서 다루어야 할 교육 분야에 대해 알아보고자 2007년 3월부터 2008년 6월까지 약 1년 4개월 동안 조사를 실시하여 수집된 자료를 통한 비교 분석으로 다음과 같은 결과를 얻었다. 1. 희망 취업조건을 조사한 결과, 희망 취업처의 경우 임상치과위생사는 치과병원 42.0%, 치과의원 28.4%, 학생은 치과병원 41.9%, 대학부속병원 및 종합병원 29.0% 순으로 나타났으며(p<0.001), 희망 근무지는 임상치과위생사와 학생 모두 서울이 각각 73.9%와 76.2%로 가장 많았다. 희망 소속부서의 경우 임상치과위생사는 진료지원팀이 33.0%로 가장 많았고, 학생은 진료팀이 41.9%로 가장 많았으며(p<0.05), 가장 선호하는 치과진료과목의 경우 임상치과위생사와 학생 모두 포괄진료가 각각 36.4%와 35.5%로 가장 많았다. 2. 치과코디네이터에 대한 인식을 살펴본 결과, 치과코디네이터에 대한 인식도는 임상치과위생사가 100%, 학생은 81.9%가 인식하는 것으로 응답하였으며 (p<0.001), 치과코디네이터 필요성에 대한 인식도는 학생이 94.8%로 85.2%의 임상치과위생사 보다 높게 나타났다(p<0.05). 치과코디네이터에 가장 적합한 직종에 대해서는 임상치과위생사의 65.9%, 학생의 84.5%가 치과위생사라고 응답하였다(p<0.01). 3. 치과코디네이터 교육이수자의 희망 직무분야의 결과, 희망 직명은 임상치과위생사는 상담실장이 34.1%로 가장 많았고, 학생은 실장(팀장)이 35.2%로 가장 많았으며, 가장 중요하다고 생각하는 직무 분야는 임상치과위생사와 학생 모두 상담이 각각 51.1%, 65.8%로 가장 많았다(p<0.05). 4. 치과코디네이터의 수행업무에 대한 인식은 임상치과위생사가 $4.00{\pm}0.41$로 학생의 $3.81{\pm}0.50$ 보다 높은 것으로 나타났다(p<0.01). 결론적으로 임상치과위생사나 학생 모두에게 희망 근무처에 따른 맞춤형 심화 교육이 필요하며 두 그룹 모두 상담과 업무 중재자로서의 기능을 최대한 발휘할 수 있는 교육 프로그램 개발과 재학여부나 임상경력을 고려한 지속적이며 체계적인 교육 프로그램 개발로 치과코디네이터의 계속적인 개발에 힘써야 할 것이다.

• Journal of Preventive Medicine and Public Health
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• 제29권2호
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• pp.239-254
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• 1996

Health services on industrial noisy environment have been provided only for noise-induced hearing loss management until now. But gradually, modem diseases and death have come to be related to stress and mental health deeply, therefore noise-induced mental disorder, like a stress became very important. In this point, the purpose of this study was to analyze the relationship between noise exposure level in worksite and workers' stress symptoms. This study included a survey of 786 manual workers selected from 89 worksites in 21 factories in Puchon. The results were as follows: 1. For demographic characteristics, most of the workers were males(80.8%), the $20\sim29years$ old were 34.5% and those who graduated from high school were 65.3%. The workers whose monthly income ranged from 100,000 to 800,000 won were 37.5% and who have a religion were 47.9%. 2. For occupational characteristics, workers who had worked $1\sim5$ years in the factories were 33.0%. Those who were much for them workload were 43.9% and who worked more than 8 hours a day were 73.9%. Those who were disatisfied with their job and pay were 31.9% and 50.6%. The workers who responsed ventilation condition of their worksites were bad were 51.9% and the dissatisfed with working environment of their worksites were 45.9%. 3. Workers who were suffering from tinnitus were 53.3% and those who perceived hearing loss were 50.1%. Persons who reported they always wore earplugs at work were 35.4%. Those who felt earplugs bigger than their ears were 30.6% and those who experienced eardiseases caused by earplugs were 25.6%. 4. For the noise exposure level in worksite, workers who were exposed to $80\sim90dB$ were 30.3%, $90\sim100dB$ were 26.4% and $50\sim70dB$ were 19.2%. 5. Workers' stress symptoms were significantly related to marital status and their monthly income(p<0.05). Workers who were single and had lower monthly income showed higher PSI (Psychiatric Symptom Index) scores than those who were married and had higher monthly income. Higher PSI scores were also significantly related to $1\sim2$ days hight-work per week, much for them workload, dissatisfaction with their job, and bad relationship with their bosses and coworkers. 6. Higher PSI scores were significantly related to severe tinnitus and perceived hearing losso(p<0.001). Workers who felt the earplugs they use did not fit their ears showed significantly higher PSI scores(p<0.01). Workers who reported that they did not feel they need earplugs showed. significantly higher PSI scores (p<0.05). Increased experience of eardisease caused by earplugs that did not fit were also significantly related to higher PSI scores(p<0.01). 7. The higher noise exposure level in worksite from 80dB was, the more severe stress symptoms including PSI subparts were reported; Anxiety, Anger, Depression, and Cognitive disorder(p<0.001). 5. According to the results of stepwise multiple regression analysis, factors affecting workers' PSI scores were perceived hearing loss$(R^2=0.160)$, noise exposure level in worksite$(R^2=0.110)$, realtionship with coworkers, amount of workload, monthly income and relationship with bosses orderly and the total $R^2$ of this 6 factors was 0.371. 9. The most significant factors that have impact on manual workers' stress symptoms were perceived hearing loss and noise exposure level in worksite, especially noise exposure level in the worksite was the most affective factor on the depression symptom.

• 한국학교ㆍ지역보건교육학회지
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• 제5권
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• pp.107-122
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• 2004

To correctly plant the value of sex to the juvenile, we cannot overemphasize the importance of the sexual education in schools. Therefore, the study for teachers' consciousness and view of sex is also necessary, because they are subjects of education and role-models of sex of their students. Especially, if teachers are over fifty in age, it is more important, because it is obvious, as they are in positions of managers and directors of education, that their view of sexual value and consciousness are influencing the aim of education and the course of education. Hereby this study was conducted to check their sexual consciousness, attitude, and condition and to prepare for the basic data needed for the development of a sexual education program suitable to them. The methods of the survey of this study are applied by modifying or supplementing those of precedented studies. They are used after analyzing reliance of items according to Cronbach's $\alpha$ figure calculating law, and modifying or supplementing items lower in reliance. The questionnaire survey was conducted among 1,000 randomly selected from teachers working in middle and high schools in Korea from June 14th in 2004 to June 30th. The survey analyzed 632 questionnaires suitable to it. The outcomes of the survey of this study are like the following: First, the objects of the survey consist of 64.6% men and 35.4% women. Among them, 41.1% are under fifty and the rest are over fifty. As for the periods of marriage, 15.5% are unmarried, 16.3% are under ten years, 18.0% are between ten and twenty, and 50.2% are over twenty. Second, with reagard to sex, 25.6% admit the necessity of a heterosexual friend. 32.0% say that they are conservative to sex. 54.1% are taught sexual education. 67.1% attribute sexual education to nursing teachers. Third, among those who answer that they enoughly know the concept of sex, seenig by age, 25.0% are under fifty and 58.1% are over fifty. Seening by the periods of marriage, 9.2% are unmarried, 28.2% are under ten, 49.1% are between ten and twenty, and 59.0% are over twenty. Among those who answer that they enoughly know the concepts of sexual harassment and sexual violence, seenig by age, in the turns by above-mentioned order, each 47.7% and 76.3%. Seening by the periods of marriage, each 9.2%, 28.2%, 49.1%, and 59.0%. Fourth, among those who answer that "teachers also need sexual education and sexual counsel," by age, each92.7% and 91.4%. By the periods of marriage, each 89.8%, 95.2%, 89.4%, and 92.4%. As a matter of course, we can infer the necessity of the sexual education and sexual counsel for teachers. Fifth, among those who answer that they are satisfied with their sexuality, by age, each 41.1% and 61.3%. By the period of marriage, each 4.1%, 63.1%, 64.1%, and 61.5%. As for the sexual desire like spiritual intercourse, physical intercourse containing sexuality, by age, each 71.9% and 93.5%. By the periods of marriage, each 54.0%, 81.5%, 90.3%, and 93.0%. The survey shows that those over fifty and having long marriage are feeling the stronger desire towards sexuality. Through the outcomes of this survey, a few suggestions are possible: First, it is necessary to check of the teachers' view of sexual value and to study deep about the sexual tendency of them in twenties, thirties, and forties. It is to make them teach their students on the firm basis, and also to develop suitable sexual education and counsel program.

• 한국언론정보학보
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• 제60권
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• pp.125-149
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• 2012

이 연구는 제작현장의 경험을 중심으로 1970년대 KBS 교양 피디의 직무 내용과 직업정체성 형성 과정을 탐색했다. 1970년대 텔레비전 피디는 경제적으로나 사회문화적으로 선망받는 직업은 아니었다. 오랫동안 편성과 영화의 하부로 남아있던 교양은 흔히 정책 계몽 프로그램의 정치적 수요, 그리고 새로운 기술 도입으로 70년대 중반부터 활성화된 것으로 서술되어 왔다. 그러나 이 연구는 모든 변화의 흐름에서 실천적 주체는 교양 피디임을 주장하고 있다. 교양 피디들은 영화 피디들의 필름 다큐멘터리 제작을 보조하며 스스로를 전문가로 훈련했고, 필름으로부터 마그네틱테이프 레코더 시대로의 전환 과정에서 교양을 특화된 전문 영역으로 독립시켜 제작의 주체로 등장했다. 척박한 제작환경에서 '잔뼈가 굵어가며' 키워왔던 "프로그램을 만드는 DNA와 정신"은 교양 피디들이 직무 전문성을 키우고 자기 정체성을 확인할 수 있었던 가장 큰 힘이었다. 그러나 70년대 교양 피디들은 압도적 국가의 헤게모니 안에서 기술과 제작의 '전문성'을 공급하는 도구적 위치를 벗어나기 어려웠다. 당대 한국 사회의 전 영역이 그러했듯이 피디집단 역시 체제가 부여한 역할을 수행할 수밖에 없었고, 프로그램을 더 잘 만들기 위한 노력과 경쟁이 유일한 자율적 실천이었다. 이러한 조건에서 KBS 교양 피디들은 공무원으로부터의 구별짓기와 상업방송과의 구별짓기라는 두 가지 전략으로 전문 방송인으로서 직업 정체성을 형성했다. 그러나 전문 직업인으로서의 윤리적 실천 규범은 개인의 도덕성 문제에 머물렀고, 방송의 공공적 책무는 상업방송과 대비한 소극적인 정당화에 그치고 있었다.

• 기본간호학회지
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• 제6권3호
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• pp.414-433
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• 1999

The purpose of this study is to identify the needs which are perceived by one of the familiy members who have head injury parients by traffic accidents in the intensive care units. Subjects were 70 families members of head injury patients admitted to 2 general hospitals NICU located Pusan city, 1 general hospital NICU located Ulsan city from December 1. 1998 to February 28. 1999. For this study, 70 family members were interviewed with aid of a Likert scale which was developed by researcher for this study. For development of the survey instrument, literature review and open questionnaire technique with family members and the nurses working in NICU. The 50needs-items were classified into 7 groups according to the homogeneity of the items with the support of literature review. For the content validity, the instrument was reviewed by 1 nursing professor and the internal reliability of this instrument was Cronbach alpha=0.94 which is highly accepted. Data was analyzed by a SPSS computer program. Data analysis included frequency. percentage, mean, standard variance and t-test or ANOVA. The results were as followings : 1. The general characteristics of head injury patients shows that the male was 74.3%, the female was 25.7% and age distribution shows that the fifty-fifty nine years was 30%, the highest. Of religion the buddhism was the most, The diagnosis distribution shows that epidural hematoma was 32.9% and subdural hematoma was 24.3%. The mentalility distribution shows that semicoma was 31.4% and stupor was 31.4%. Hemiplegia was 42.9% 2. The general charaterisrics of the family needs of head injury patients shows that thirty-thirty nine years was 31.4%, the highest. sex distribution shows that the male was 20%, the female was 80%. Of religion the buddism was the most. 3. The family needs of head injury patients was $3.03{\pm}0.42$, needs for the information of a patient's condition was $3.65{\pm}0.48$, the highest. And needs for the information of care and treatment was $3.48{\pm}0.48$, needs to be supplied with comfortable facilities for family was $3.04{\pm}0.66$, needs to be participate in a patient's care was $2.90{\pm}0.55$, needs to be informed about the available resources was $2.83{\pm}0.59$, needs to be supported emotionally for family was $2.79{\pm}0.55$, needs for religious assistance was $2.51{\pm}0.85$. 4. Examining the family needs of head injury patients according to patient's characteristics, mentality, plegia degree and operation were shown be variables to make an effect on the needs for the head injury patients family. At all, according to severity of head. injury, the family needs of head injury patients was high. 5. Examining the family needs of head injury patients according to their general characteristics, we could know that religion, job. income were shown to be variables to make an effect on the family needs. Through the examination it can be seen that the characteristics of head injury patients and the family needs of head injury patients. In conclusion, the family needs of head injury patients was almost same the family needs of ICU patients. Therefore we must involve the family's care of head injury patients and we must provide exact and repeated explanation, education and support the family of head injury patients. As this study was resulted in selecting the families admitted to NICU of some general hospital, we couldn't stretch the result in our favor. Therefore, continuous studies are suggested.

• 한국산림과학회지
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• 제83권2호
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• pp.211-220
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• 1994

임도(林道)는 산림자원(山林資源) 조성(造成) 및 벌출작업(伐出作業) 등(等) 산림(山林)의 운영관리면(運營管理面)에서는 물론이고 일반인(一般人)의 보건휴양(保健休養)과 관광(觀光), 그리고 공도(公道) 기능면(機能面)에서도 임도설치(林道設置)가 절실히 요구(要求)된다. 따라서 본(本) 연구(硏究)는 강원도(江原道)의 국유림(國有林) 4개소(個所)와 전라북도(全羅北道)의 송유림(私有林) 4개소(個所)의 기설(旣設) 임도(林道)에 대하여 산림(山林)의 몇 가지 요인별(要因別) 설치효과(設置效果)를 분석(分析)하여 산림(山林)의 다각적(多角的)인 기능(機能) 제고(提高)를 위한 임도(林道)의 개설유형(開設類型)을 제시(提示)코자 분석(分析)한 결과(結果)는 다음과 같다. 1. 지형적(地形的) 요인(要因)과 지역사회적(地域社會的) 요인(要因)이 양호(良好)한 지역(地域)에서 투자효율(投資效率)이 높게 나타났고, 산림실태적(山林實態的) 요인(要因)과 임도구조적(林道構造的) 요인(要因)이 양호(良好)한 지역(地域)에서 투자효율(投資效率)이 낮게 나타났다. 이는 현재(現在)의 산림실태(山林實態)를 감안할 때 임업이외(林業以外)의 이용(利用)에 큰 비중(比重)을 두고 임도(林道)를 설치(設置)한 것으로 생각되어 금후(今後) 지형적(地形的) 요인(要因)이 불리한 지역(地域)에는 '산지자원화형(山地資源化型)'의 임도(林道)를, 산림실태적(山林實態的) 요인(要因)이 양호(良好)한 지역(地域)에는 '산지이용형(山地利用型)'의 임도(林道)를 설치(設置)해야 개설효과(開設效果)를 증대(增大)시킬 수 있을 것이다. 2. 효과적(效果的)인 임도(林道)를 개설(開設)하기 위해서 다목적(多目的)으로 이용(利用)할 수 있는 노선(路線)을 선정(選定)하되, 제반요인(諸般要因)에 의해서 분석(分析)한 종합평가(綜合平價) 점수(點數)가 높은 지역(地域)에 우선 설치(設置)하므로써 개설효과(開設效果)를 더욱 증대(增大)시킬 수 있을 것이다. 3. 임도(林道)의 유형구분(類型區分)은 산림실태적(山林實態的) 요인비(要因比)와 임도구조적(林道構造的) 요인비(要因比)가 60% 이상인 지역(地域)은 '산지이용형(山地利用型)', 산림실태적(山林實態的) 요인비(要因比)를 비롯한 모든 요인비(要因比)가 60% 이하인 지역(地域)은 '산지자원화형(山地資源化型)', 지형적(地形的) 요인비(要因比)와 임도구조적(林道構造的) 요인비(要因比) 및 지역사회적(地域社會的) 요인비(要因比)가 60% 이상인 지역(地域)은 '지역개선형(地域改善型)', 지형적(地形的) 요인비(要因比)를 비롯한 모든 요인비(要因比)가 60% 이상인 지역(地域)은 '보건휴양형(保健休養型)', 그리고 지역사회적(池域社會的) 요인비(要因比)와 산림실태적(山林實態的) 요인비(要因比)가 60% 이상인 지역(地域)은 '복합개발형(複合開發型)' 등(等)으로 구분(區分)하여 특징(特徵)있는 임도(林道)를 개발(開發)하는 것이 합리적(合理的)일 것이다.

• 한국식품위생안전성학회지
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• 제30권2호
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• pp.159-165
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• 2015

국내 최대 인삼 재배지인 충남 금산군 소재의 인삼류(백삼, 홍삼) 제조업체 3곳을 대상으로 하여 수삼, 용수 등의 원부재료와 공정별 인삼류, 그리고 작업도구, 제조설비, 작업장 환경 및 작업자 개인위생에 대해 미생물 오염도를 조사하였다. 먼저 원료수삼과 제조 공정별 인삼의 경우 일반세균은 1.8~4.9 log CFU/g, 대장균군은 1.2~3.0 log CFU/g, 곰팡이는 0.8~4.1 log CFU/g으로 검출되었고, 병원성 미생물은 일부 시료에서 B. cereus만 미미한 수준으로 검출되었다. 특히 일반세균의 경우는 공정을 거치면서 오염도가 감소되어 완제품인 백삼에서는 2.7 log CFU/g, 홍삼에서는 1.8 log CFU/g으로 검출되었고, 곰팡이의 경우 홍삼 제조과정 중 증숙 후에 오염도가 증가하였다가 이후 공정에서 다시 감소하는 것으로 확인되었다. 제조설비와 작업 도구에서는 일반세균 $1.7{\sim}4.7log\;CFU/100cm^2$, 대장균군 $0.4{\sim}4.0log\;CFU/100cm^2$, 곰팡이 $0.9{\sim}4.2log\;CFU/100cm^2$의 수준으로 검출되었으며, 흙과 이물의 잔존할 가능성이 높은 세척기와 탈피기에서 비교적 높은 수치로 검출됨을 확인하였다. 작업자의 개인위생에서는 일반작업자가 실 묶음 작업자에 비해 미생물 오염도가 대체로 높은 것으로 확인되었고, 일부 작업자의 손에서는 S. aureus가 0.2~0.7 log CFU/hand 수준으로 검출되었다. 공중낙하균은 일반세균, 대장균군, 곰팡이만 미미한 수준으로 검출되었다. 따라서 인삼류 제품의 미생물 오염을 방지하기 위해서는 인삼류의 가열 또는 건조 시 적절한 온도와 시간의 준수, 제조시설의 청결 관리가 필요할 것으로 생각된다.

• 한국축산시설환경학회지
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• 제16권2호
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• pp.143-152
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• 2010

본 연구에서는 Lemna P.의 인공배양 조건을 파악하고 생산된 바이오매스의 영양적 가치에 관하여 조사하였다. Lemna P.의 배양을 위해 총용적 $2,630\;cm^3$, 유효용적 $2,240\;cm^3$의 생물배양조를 이용하였으며 인공광원 6,250 lux, 평균온도 $28^{\circ}C$ 조건에서 인공폐수를 이용하여 배양하였다. 물 유동여부가 Lemna P.의 생장에 미치는 영향을 분석한 결과 하부층의 물 유동이 없는 경우 일일 1.1 이상의 성장률을 보인반면 하부층 물 유동이 있는 경우에는 단지 $0.15\;d^{-1}$의 생장률을 보였다. 또한 인공 폐수내 $NH_4$-N 농도변화와 광 조사시간이 Lemna P. 성장에 마치는 영향을 분석한 결과 광주기 $16h\;d^{-1}$에서의 생장률이 8h 및 $24h\;d^{-1}$에서 보다 높았으며 Lemna P.의 생장은 초기 $NH_4$-N의 농도에 크게 영향을 받는 것으로 나타났다. 초기 $NH_4$-N의 농도가 낮을수록 Lemna P.의 생장률은 높았으나 조단백질 함량은 초기$NH_4$-N 농도에 비례하였다. $NH_4$-N의 농도 2, 10, 50, $100\;mg\;L^{-1}$에서 배양한 후의 Lemna P.의 조단백질 함량은 각각 18, 24, 37, 43%로 50과 $100\;mg\;L^{-1}$ 농도에서 생장한 Lemna P. 바이오매스의 조단백질함량은 현재 단백질원으로 이용되고 있는 아마박(조단백질 함량 35%), 면실박(38%), 대두박(45%)과 비슷한 수준으로 나타났다. 광주기 $16h\;d^{-1}$ 초기 $NH_4$-N 농도 $2\;mg\;L^{-1}$ 이하에서 매우 높은 생장률로 증식한 Lemna P.의 조지방, 조단백질, 조섬유, 조회분, NDF 및 ADF 함량이 각각 2.77, 18.03, 27.02, 20.01, 41.00, 65.68%로 밝혀짐에 따라 우수한 단백질 또는 섬유질 대체자원의 대량 생산이 가능함을 알 수 있었다. 특히 Lemna P.는 식물성 지방보다 동물성 지방에서 검출되는 단일 및 다중 불포화 지방산들을 함유하고 있으며, 가능성 지방산으로 알려진 C18:1n9c, C18:2n6c, C20:5n3 및 C22:2 들을 지나고 있어 가축의 가능성 사료자원으로 활용가치가 높을 것으로 판단되었다.

• Journal of Biosystems Engineering
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• 제1권1호
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• pp.1-6
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• 1976

This paper is the third one of the study on balanced type oscillating mole-drainer, the first one was presented in No 9. Gyeongsang College Report and the second one in Vol. 17, No.4 of the KSAE. In the first part of this study, the characteristics of traction forces between the nonoscillating earth working equipments and oscillating ones was compared. A model of the balanced type oscillating mole-drainer, which composed of a mechanism that may reduce the machine vibration, was designed following the dimensional analysis and similitude technique. The model test was carried out to clarify the balancing mechanism of the oscillating parts and other parts of the machine. In the light of the results from the model tests, a prototype machine was made for experimental purpose. Results from the field test by a reported in the near future. In the second report, the model tests were carried out under the same soil conditions, i.e, . oscillating frequency, running velocity, and oscillating amplitude, etc. It was clear that use of balanced type oscillating model could substantially reduce the vibration of the whole system of the machine, when compared with the nonoscillating type model. In this paper(the third report), results of investigation on the traction force, power requirement, and moment. etc, is presented. Analysis of variance technique was used for analyzing the effect of the frequency, amplitude, and running velocity on the draft force, torque, power requirements, and moments. The results obtained from the model tests are as follows, 1) By practicing a balanced-type oscillating mole-drainer, it was possible to reduce the traction resistance by 55.1-61. 2 percent of traction resistance, however, was 1.75 - 1.95 times greater than the value of resistance which was induced by use of a mole-drainer with single bullet. The resistance of rear shank against soil was considered as a main causing factor of the above results. 2) As the oscillation frequency was increased, the traction resistance was decreased. Considering on the effect of oscillation the greater the amplitude, and the slower the running velocity was, the greater the reduction ratio of traction resistance was. 3) The ratio of the traction resistance of oscillating mole-drainer to that of non-oscillating one could be represented as a function of dimensionless variable (V/$Af$). The results from the tests were well agreed with the reported results from the experim ents on oscillation plow or hoe. 4) By taking a lower value of (V/$Af$), reducing the traction resistance was possible. This fact meant, however, that the efficiency of mole drain practice would be lower. 5) It was experimentally confirmed under the same condition of soil that the variable (R/$rD1^3$) could be represented as a function of a variable($V^2/gD$) when a non\ulcornerocillating mole-drainer was used. 6) When a oscillating mole-drainer was used, the variable(R/$rD_1^{3}$) could be represented as a function of two variables ($v^2/gD_1$) and (V^2/gD_1$). 7) The torque was not affected by a change of frequency. However, a relation of proportionality existed between torque and amplitude, running velocity, and ratio of bullet diameter. When a balanced type oscillating mole-drainer with two bullets was used, torque was increased by 52.8-78. 4 percent and total power requirement was also increased. 8) Total power requirement was increased linearly in accordance with the increasing frequency, 41.96 percent of total power was used for oscillating action. The magnitude of total power requirement was 1. 8-9. 4 times greater than that of a non-oscillating mechanism. In the view point of power requirement, it was not advisable to increase the frequency, amplitude, running velocity, and ratio of bullet diameter at the same time. 9) Only the positive moment occured in the rear shank. Change of the diameter of a rear bullet, could not affect the balancing against the soil resistance. It was necessary for rear bullet to have a large resistance against soil only when the rear bullet was in backward motion. 10) Within an extent of the experimental base, optimum limits for several design factors were A=0.5cm, $f$=22.5Hz, V=O. 05m/sec, and $\lambda$=1.0 By adapting these values traction resistance was reduced by 40 percent and vibration acceleration wa s reduced by 60 percent. Even though the total , power requirements for operating a balanced type oscillation mechanism was greater ~than that of non-oscillating one, using a oscillating mechanism would be more effective. Because a balanced type oscillating mechanism is used, tractive resistance will be reduced and then the lighter . tractive equipment could be used.

• Journal of Animal Science and Technology
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• 제45권5호
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• pp.875-884
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• 2003

본 연구에서는 축산폐수내에 고농도로 함유되어 있는 질소와 인을 재생하기 위한 공정으로서의 struvite 결정화 방법의 운전인자를 파악하고 폐수처리 측면에서 효율적인 struvite법과 전기분해법과의 연계공정을 도출하고자 하였다. 유효용적인 2L인 Struvite 반응조를 이용하여 주입원의 종류, pH, 교반과 폭기 등에 따른 암모니아와 인의 결정화 특성을 파악하였으며, 효율적인 전기분해법과의 연계방법을 찾고자 6가지 서로 다른 방법에서의 NH$_4$-N과 PO$_4$$^{3-}$의 제거특성을 분석하였다. 시험결과 struvite 형성을 위한 주입원으로는 CaCO$_3$나 CaCl$_2$ 보다는 MgSO$_4$ 혹은 MgCl$_2$을 사용하는 것이 효율적인 것으로 판단되었다. 공기주입과 교반이 struvite 결정화 반응에 미치는 영향을 파악한 시험에서는 포기의 경우 pH가 8.5이상으로 상승하면서 인 제거효율이 90%에 도달하는데 1시간이 걸린 반면 교반의 경우에는 14시간이 걸리는 것으로 나타나 포기가 교반보다 빠른 pH 상승효과를 가져오면서 struvite 결정화 반응을 촉진함을 알 수 있었다. 포기조건에서의 struvite 결정화는 유입폐수의 pH에 영향을 받는 것으로 나타났는데 유입폐수의 pH가 5수준일 때는 아무런 결정화가 이루어지지 않았으며 pH 6, 7, 9 에서는 struvite 결정화가 활발하여 각각 3시간, 2시간, 10분만에 90%의 PO$_4$$^{3-}$가 struvite 반응으로 제거되었다. 그러나 pH 10 이상에서는 과량의 거품발생으로 인한 운전의 어려움이 목격되었으며 pH 11에서는 struvite 결정화 반응이 둔화되는 것으로 나타났다. 이상의 결과와 축산폐수의 pH의 범위가 7~9 수준임을 감안할 때 축산폐수의 경우에는 아무런 pH 조절제를 사용하지 않고도 포기만으로도 효율적인 결정화 반응 유도가 가능함을 알 수 있었다. 전기분해법을 struvite 반응과 연계하여 폐수내 인과 질소 제거효율을 높이기 위해서는 struvite 결정화 반응과 전기분해를 모두 포기 조건에서 수행하면서 struvite 반응 후에 상등액을 전기분해 하는 것이 시험된 공정 중 가장 효율적인 것으로 나타났다. 본 공정에서의 인과 암모니아성 질소의 제거 효율은 각각 98%와 86%이었으며 색도 제거효율은 92.4%이었다.