• Title/Summary/Keyword: 7단계 접근방법

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Probability-based Pre-fetching Method for Multi-level Abstracted Data in Web GIS (웹 지리정보시스템에서 다단계 추상화 데이터의 확률기반 프리페칭 기법)

  • 황병연;박연원;김유성
    • Spatial Information Research
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    • v.11 no.3
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    • pp.261-274
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    • 2003
  • The effective probability-based tile pre-fetching algorithm and the collaborative cache replacement algorithm are able to reduce the response time for user's requests by transferring tiles which will be used in advance and determining tiles which should be removed from the restrictive cache space of a client based on the future access probabilities in Web GISs(Geographical Information Systems). The Web GISs have multi-level abstracted data for the quick response time when zoom-in and zoom-out queries are requested. But, the previous pre-fetching algorithm is applied on only two-dimensional pre-fetching space, and doesn't consider expanded pre-fetching space for multi-level abstracted data in Web GISs. In this thesis, a probability-based pre-fetching algorithm for multi-level abstracted in Web GISs was proposed. This algorithm expanded the previous two-dimensional pre-fetching space into three-dimensional one for pre-fetching tiles of the upper levels or lower levels. Moreover, we evaluated the effect of the proposed pre-fetching algorithm by using a simulation method. Through the experimental results, the response time for user requests was improved 1.8%∼21.6% on the average. Consequently, in Web GISs with multi-level abstracted data, the proposed pre-fetching algorithm and the collaborative cache replacement algorithm can reduce the response time for user requests substantially.

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A Study about modification of Gejitang that showed on sympton and prescription about Soumin (소음인(少陰人) 병증(病證) 및 처방(處方)에 나타난 계기장(桂技場)의 변용(變用)에 대한 고찰(考察))

  • Kim, Jeong-hee;Song, Jeong-mo
    • Journal of Sasang Constitutional Medicine
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    • v.11 no.1
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    • pp.201-220
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    • 1999
  • We got these results after studying about modification of Gejitang(桂枝湯) that showed on sympton and prescription about Soumin(少陰人). 1. There are totally eleven prescriptions related to Gejitang appeared on Dongyi-Soose-Bowon(東醫壽世保元). Among them, one is prescription of Danguisayoktang(當歸四逆湯) in prescription of Discussion of Cold Induced Disorder(傷寒論) and another is Gejibujatang(桂枝附子湯) in Won-Myung dynasty period(元明時代). There are nine prescriptions in LeeJae-Ma(李濟馬)'s pre-scription and we can see there are many prescriptions used prescriptions related to Gejitang for Mang Yang(亡陽). 2. Pre-scriptions related to Gejitang has seven prescriptions in Extra-disease(表病證), and two prescriptions in Intra-disease(裏病證) which are analyzed as modified prescription from Gejitang. 3. Although 藿香正氣散, 香蘇散, 芎歸香蘇散, 八物君子湯 etc. are not modified prescriptions of Gejitang, We can see that its are brought up to be on the same with alternative remedy of Gejitang in each step of symptoms. 4. Symptoms are exactly classified in Soumin, the prescription which is used in different symptoms of diseases is similar in raw materials. It's because the remedy of Acending and Descending(升降) is used under the same purpose that maintain Yangnan Qi(陽暖之氣). 5. We could realize that Panax gienseng(人蔘), Cinnamomum Cassia(肉桂) and Aconitum Carrnichali(附子) are commonly important to reinforce Yangnan Qi because the more disease got worse, the more patient lost Yangnan Qi on both Extra-disease and Intra-disease in the Soumin's disease.

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Effect of Staged Education Program for Hypertension, Diabetes Patients in a Community (Assessment of Quality of Life Using EQ-5D) (일 지역에서의 EQ-5D를 이용한 고혈압·당뇨병 교육프로그램 이수자의 삶의 질 평가)

  • Lee, Jung Jeung;Lee, Hye Jin;Park, Eun Jin
    • Journal of agricultural medicine and community health
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    • v.39 no.1
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    • pp.37-45
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    • 2014
  • Objective: This study was conducted in order to evaluate an education program for cardio-cerebrovascular high-risk patients. Methods: To evaluate patients' quality of life, EQ-5D was used and an organized survey was conducted via calls and interviews for hypertension, diabetes patients who had visited the KHyDDI(Korea Hypertension Diabetes DaeguInitiative) education center or 70 clinics through out the nation. Results: The subjects included 537 patients, 320 of who were in the clinic education and 217 of who were in the education center program. Sixty eight of the subjects went through the EQ-5D evaluation before and after the education program. In the EQ-5D index distribution of their quality of life before the education program, there was a statistically significant difference in gender(p<0.001) with higher points among males. Regarding age, there was a statistically significant difference between those aged over 65 years and under 65(p<0.001), with higher points in the group under the age of 65. Further, the EQ-5D 5 scope index was statistically significant different before and after receiving the education(p<0.05). Conclusion: Therefore, the KHyDDI staged education program is effective for improving the quality of life. Moreover, it could contribute to the complications of the disease through a variety of approaches by considering both gender and age.

A Study on the Differences in Environmental Perceptions of the Interest Groups in the Protected Areas: Focused on Seoraksan National Park (보호지역 이해집단간 환경의식 차이에 관한 연구 -설악산 국립공원을 중심으로-)

  • Kim, Jeongmin
    • Korean Journal of Environment and Ecology
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    • v.28 no.6
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    • pp.779-788
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    • 2014
  • This study, as a case where the environmental conflict and dispute arose between the use and the conservation as in the other protected areas in Korea, took the first step to build ecological citizenship to solve various and complicated issues in a fundamental level by providing a basic information on differentiated environmental perceptions of the locality and the visitors of Seoraksan National Park. The questionnaire survey was employed on September 6th and 7th with 150 residents of the park area and 200 visitors of Osaek-Daechungbong trail. Total number of 13 survey questions was introduced using Dunlap and Liere's NEP index. The result shows that the perception of 'balance of nature' was more dominant to the perception of 'humans over nature' and the perception to the 'limits to growth' was also somewhat positive in both groups. The differences in environmental perceptions between the groups exist; the visitor group tended to have more positive level of acceptance of NEP views. Such differences in perceptions suggest that a different normative approach should be taken to the residents of the national park with less pro-environment in their perceptions when policy making. It thus seemed possible that ecological citizenship could be realized since the younger and the higher education level are, the more pro-environment. The findings of the research may cause some concerns however, because the study has been confined as a case study with basic understanding of environmental perceptions and its differences between the interest groups. More extensive research is required to confirm if this is generalized.

Roles and Preparation for the Future Nurse-Educators (미래 간호교육자의 역할과 이를 위한 준비)

  • Kim Susie
    • The Korean Nurse
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    • v.20 no.4 s.112
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    • pp.39-49
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    • 1981
  • 기존 간호 영역 내 간호는 질적으로, 양적으로 급격히 팽창 확대되어 가고 있다. 많은 나라에서 건강관리체계가 부적절하게 분배되어 있으며 따라서 많은 사람들이 적절한 건강관리를 제공받지 못하고 있어 수준 높은 양질의 건강관리를 전체적으로 확대시키는 것이 시급하다. 혹 건강관리의 혜택을 받는다고 해도 이들 역시 보다 더 양질의 인간적인 간호를 요하고 있는 실정이다. 간호는 또한 간호영역 자체 내에서도 급격히 확대되어가고 있다. 예를들면, 미국같은 선진국가의 건강간호사(Nurse practitioner)는 간호전문직의 새로운 직종으로 건강관리체계에서 독자적인 실무자로 그 두각을 나타내고 있다. 의사의 심한 부족난으로 고심하는 발전도상에 있는 나라들에서는 간호원들에게 전통적인 간호기능 뿐 아니라 건강관리체계에서 보다 많은 역할을 수행하도록 기대하며 일선지방의 건강센터(Health center) 직종에 많은 간호원을 투입하고 있다. 가령 우리 한국정부에서 최근에 시도한 무의촌지역에서 졸업간호원들이 건강관리를 제공할 수 있도록 한 법적 조치는 이러한 구체적인 예라고 할 수 있다. 기존 간호영역내외의 이런 급격한 변화는 Melvin Toffler가 말한 대로 ''미래의 충격''을 초래하게 되었다. 따라서 이러한 역동적인 변화는 간호전문직에 대하여 몇가지 질문을 던져준다. 첫째, 미래사회에서 간호영역의 특성은 무엇인가? 둘째, 이러한 새로운 영역에서 요구되는 간호원을 길러내기 위해 간호교육자는 어떤 역할을 수행해야 하는가? 셋째 내일의 간호원을 양성하는 간호교육자를 준비시키기 위한 실질적이면서도 현실적인 전략은 무엇인가 등이다. 1. 미래사회에서 간호영역의 특성은 무엇인가? 미래의 간호원은 다음에 열거하는 여러가지 요인으로 인하여 지금까지의 것과는 판이한 환경에서 일하게 될 것이다. 1) 건강관리를 제공하는 과정에서 컴퓨터화되고 자동화된 기계 및 기구 등 새로운 기술을 많이 사용할 것이다. 2) 1차건강관리가 대부분 간호원에 의해 제공될 것이다. 3) 내일의 건강관리는 소비자 주축의 것이 될 것이다. 4) 간호영역내에 많은 새로운 전문분야들이 생길 것이다. 5) 미래의 건강관리체계는 사회적인 변화와 이의 요구에 더 민감한 반응을 하게 될 것이다. 6) 건강관리체계의 강조점이 의료진료에서 건강관리로 바뀔 것이다. 7) 건강관리체계에서의 간호원의 역할은 의료적인 진단과 치료계획의 기능에서 크게 탈피하여 병원내외에서 보다 더 독특한 실무형태로 발전될 것이다. 이러한 변화와 더불어 미래 간호영역에서 보다 효과적인 간호를 수행하기 위해 미래 간호원들은 지금까지의 간호원보다 더 광범위하고 깊은 교육과 훈련을 받아야 한다. 보다 발전된 기술환경에서 전인적인 접근을 하기위해 신체과학이나 의학뿐 아니라 행동과학 $\cdot$ 경영과학 등에 이르기까지 다양한 훈련을 받아야 할 필요가 있다. 또한 행동양상면에서 전문직인 답게 보다 진취적이고 표현적이며 자동적이고 응용과학적인 역할을 수행하도록 훈련을 받아야 한다. 그리하여 간호원은 효과적인 의사결정자$\cdot$문제해결자$\cdot$능숙한 실무자일 뿐 아니라 소비자의 건강요구를 예리하게 관찰하고 이 요구에 효과적인 존재를 발전시켜 나가는 연구자가 되어야 한다. 2. 미래의 간호교육자는 어떤 역할을 수행해야 하는가? 간호교육은 전문직으로서의 실무를 제공하기 위한 기초석이다. 이는 간호교육자야말로 미래사회에서 국민의 건강요구를 충족시키기는 능력있는 간호원을 공급하는 일에 전무해야 함을 시사해준다. 그러면 이러한 일을 달성하기 위해 간호교육자는 무엇을 해야 하는가? 우선 간호교육자는 두가지 측면에서 이 일을 수정해야 된다고 본다. 그 하나는 간호교육기관에서의 측면이고 다른 하나는 간호교육자 개인적인 측면엣서이다. 우선 간호교육기관에서 간호교육자는 1) 미래사회에서 요구되는 간호원을 교육시키기 위한 프로그램을 제공해야 한다. 2) 효과적인 교과과정의 발전과 수정보완을 계속적으로 진행시켜야 한다. 3) 잘된 교과과정에 따라 적절한 훈련을 철저히 시켜야 한다. 4) 간호교육자 자신이 미래의 예측된 현상을 오늘의 교육과정에 포함시킬 수 있는 자신감과 창의력을 가지고 모델이 되어야 한다. 5) 연구 및 학생들의 학습에 영향을 미치는 중요한 의사결정에 학생들을 참여시키도록 해야한다. 간호교육자 개인적인 측면에서는 교육자 자신들이 능력있고 신빙성있으며 간호의 이론$\cdot$실무$\cdot$연구면에 걸친 권위와 자동성$\cdot$독창성, 그리고 인간을 진정으로 이해하려는 자질을 갖추도록 계속 노력해야 한다. 3. 미래의 간호원을 양성하는 능력있는 간호교육자를 준비시키기 위한 실질적이면서도 현실적인 전략은 무엇인가? 내일의 도전을 충족시킬 수 있는 능력있는 간호교육자를 준비시키기 위한 실질적이고 현실적인 전략을 논함에 있어 우리나라의 실정을 참조하겠다. 전문직 간호교육자를 준비하는데 세가지 방법을 통해 할 수 있다고 생각한다. 첫째는 간호원 훈련수준을 전문직 실무를 수행할 수 있는 단계로 면허를 높이는 것이고, 둘째는 훈련수준을 더 향상시키기 위하여 학사 및 석사간호교육과정을 발전시키고 확대하는 것이며, 셋째는 현존하는 간호교육 프로그램의 질을 높이는 것이다. 첫째와 둘째방법은 정부의 관할이 직접 개입되는 방법이기 때문에 여기서는 생략하고 현존하는 교과과정을 발전시키고 그 질을 향상시키는 것에 대해서만 언급하고자 한다. 미래의 여러가지 도전에 부응할 수 있는 교육자를 준비시키는 교육과정의 발전을 두가지 면에서 추진시킬 수 있다고 본다. 첫째는 국제간의 교류를 통하여 idea 및 경험을 나눔으로서 교육과정의 질을 높일 수 있다. 서로 다른 나라의 간호교육자들이 정기적으로 모여 생각과 경험을 교환하고 연구하므로서 보다 체계적이고 효과적인 발전체인(chain)이 형성되는 것이다. ICN같은 국제적인 조직에 의해 이러한 모임을 시도하는 것인 가치있는 기회라고 생각한다. 국가간 또는 국제적인 간호교육자 훈련을 위한 교육과정의 교환은 한 나라안에서 그 idea를 확산시키는데 효과적인 영향을 미칠 수 있다. 충분한 간호교육전문가를 갖춘 간호교육기관이 새로운 교육과정을 개발하여 그렇지 못한 기관과의 연차적인 conference를 가지므로 확산시킬 수도 있으며 이런 방법은 경제적인 면에서도 효과적일 뿐만 아니라 그 나라 그 문화상황에 적합한 교과과정 개발에도 효과적일 수 있다. 간호교육자를 준비시키는 둘째전략은 현존간호교육자들이 간호이론과 실무$\cdot$연구를 통합하고 발전시키는데 있어서 당면하는 여러가지 요인-전인적인 간호에 적절한 과목을 이수하지 못하고 임상실무경험의 부족등-을 보충하는 방법이다. 이런 실제적인 문제를 잠정적으로 해결하기 위하여 1) 몇몇 대학에서 방학중에 계속교육 프로그램을 개발하여 현직 간호교육자들에게 필요하고 적절한 과목을 이수하도록 한다. 따라서 임상실무교육도 이때 실시할 수 있다. 2) 대학원과정 간호교육프로그램의 입학자의 자격에 2$\~$3년의 실무경험을 포함시키도록 한다. 결론적으로 교수와 학생간의 진정한 동반자관계는 자격을 구비한 능력있는 교수의 실천적인 모델을 통하여서 가능하게 이루어 질수 있다고 믿는 바이다.

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A Preliminary Study of Ecological Aspects of Food on a Kind of Gom-Tang(Beef Soup made with Internal Organs and Bone) Intake (식생태학적(食生態學的) 관점(觀點)에서 본 곰탕류(類) 섭취(攝取)에 관한 예비적연구(豫備的硏究))

  • Kwon, Sun-Ja;Adachi, Miyuki;Mo, Su-Mi;Choi, Kyung-Suk;Kim, Ju-Hye;Koh, Hee-Jung
    • Journal of the Korean Society of Food Culture
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    • v.6 no.4
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    • pp.421-432
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    • 1991
  • This study was conducted to investigate the intake of a kind of Gom-Tang (Beef soup made with internal organs and bone), which is the Korean traditional food, and factors affecting the eating behavior of customers. Two hundred male customers of a H Korean Restaurant specialized in Gom-Tang, which is a well-known restaurant in Seoul, were surveyed from June 26 to 29, 1990. The results were shown as follows. (1) ${\ulcorner}$Frequency of intake${\lrcorner}$ and ${\ulcorner}$preference${\lrcorner}$ were very high. Those who took a kind of Gom-Tang ${\ulcorner}$more than once a week${\lrcorner}$ were 66.5% of the subjects. Those who evaluated ${\ulcorner}$good${\lrcorner}$ for the taste and flavor were 86.5% and 59.0% of the subjects, respectively. (2) The reasons why they chose a kind of Gom-Tang from among many Korean traditional foods were ${\ulcorner}$preference${\lrcorner}$ and ${\ulcorner}$phygiological condition${\lrcorner}$ in ${\ulcorner}$high frequency of intake${\lrcorner}$ group. ${\ulcorner}$Phygiological condition${\lrcorner}$ was more critical factor than ${\ulcorner}$preference${\lrcorner}$ in ${\ulcorner}$low frequency of intake${\lrcorner}$ group. (3) The effect of the intake of a kind of Gom-Tang on health was evaluated as ${\ulcorner}$healthy${\lrcorner}$ (80.5%). ${\ulcorner}$No effect${\lrcorner}$ and ${\ulcorner}$harmful${\lrcorner}$ were 30.5% and 6.5%, respectively. (4) ${\ulcorner}$High frequency of intake${\lrcorner}$ group, mainly more than 50 years of age, had a high ${\ulcorner}$preference${\lrcorner}$ and ${\ulcorner}$food knowledge${\lrcorner}$ as well as positive ${\ulcorner}$eating behavior${\lrcorner}$ and ${\ulcorner}$healthy state${\lrcorner}$, ${\ulcorner}$Middle frequency of intake${\lrcorner}$ group, mainly the forties, had a high ${\ulcorner}$preference${\lrcorner}$, but had less positive ${\ulcorner}$eating behavior${\lrcorner}$ than ${\ulcorner}$high frequency of intake${\lrcorner}$ group. ${\ulcorner}$Low frequency of intake${\lrcorner}$ group, mainly the twenties and thirties, had a medial ${\ulcorner}$preference${\lrcorner}$. They took a kind of Gom-Tang for reasons of ${\ulcorner}$on the recommendation of friends${\lrcorner}$ better than ${\ulcorner}$preference${\lrcorner}$. Foregoing results showed that ${\ulcorner}$a kind of Gom-Tang${\lrcorner}$ was a typical food recognized as ${\ulcorner}$healthy${\lrcorner}$ as well as ${\ulcorner}$delicious${\lrcorner}$. This may suggest that ${\ulcorner}$a kind of Gom-Tang${\lrcorner}$ is a candidate for the effective food on nutritional education.

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Development for Fishing Gear and Method of the Non-Float Midwater Pair Trawl Net (II) - Opening Efficiency of the Model Net according to Front Weight and Wing-end Weight - (무부자 쌍끌이 중층망 어구어법의 개발 (II) - 추와 날개끝 추의 무게에 따른 모형어구의 전개성능 -)

  • 유제범;이주희;이춘우;권병국;김정문
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.39 no.3
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    • pp.189-196
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    • 2003
  • In this study, the vertical opening of the non-float midwater pair trawl net was maintained by controlling the length of upper warp. This was because the head rope was able to be kept linearly and the working depth was not nearly as changed with the variation of flow speed as former experiments in this series of studies have demonstrated. We confirmed that the opening efficiency of the non-float midwater pair trawl net was able to be developed according to the increase in front weight and wing-end weight. In this study, we described the opening efficiency of the non-float midwater pair trawl net according to the variation of front weight and wing-end weight obtained by model experiment in circulation water channel. We compared the opening efficiency of the proto type with that of the non-float type. The results obtained can be summarized as follows:1. The hydrodynamic resistance was almost increased linearly in proportion to the flow speed and was increased in accordance with the increase in front weight and wing-end weight. The increasing rate of hydrodynamic resistance was displayed as an increasing tendency in accordance with the increase in flow speed. 2. The net height of the non-float type was almost decreased linearly in accordance with the increase in flow speed. As the reduced rate of the net height of the non-float type was smaller than that of the net height of the proto type against increase of flow speed, the net height of the non-float type was bigger than that of the proto type over 4.0 knot. The net width of the non-float type was about 10 m bigger than that of the proto type and the change rate of net width varied by no more than 2 m according to the variation of the front weight and wing-end weight. 3. The mouth area of the non-float type was maximized at 1.75 ton of the front weight and 1.11 ton of the wing-end weight, and was smaller than that of the proto type at 2.0∼3.0 knot, but was bigger than that of the proto type at 4.0∼5.0 knot. 4. The filtering volume was maximized at 3.0 knot in the proto type and at 4.0 knot in the non-float type. The optimal front weight was 1.40 ton.

DEVELOPMENT OF THREE DIMENSIONAL MEASURING PROGRAM WITH FRONTAL AND LATERAL CEPHALOMETRIC RADIOGRAPHS -PART 1. COMPUTATION OF THE THREE-DIMENSIONAL COORDINATES BY COMPENSATION OF THE ERROR OF THE HEAD POSITION IN ORDINARY NON-BIPLANAR CEPHALOSTAT- (정모 및 측모 두부 방사선 규격사진을 이용한 3차원 계측 프로그램의 개발 -1. 단일 방사선원으로 촬영된 두부 방사선사진의 두부 위치 보정을 이용한 3차원 좌표의 산출-)

  • Lee, Geun-Ho;Lee, Sang-Han;Jang, Hyon-Joong;Kwon, Tae-Geon
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.27 no.3
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    • pp.214-220
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    • 2001
  • The clinical application of the three-dimensional radiographic technique had been limited to standard Broadbent-Bolton cephalometer with biplanar stereoradiography. We developed a new method for compensating the error of head position in ordinary non-biplanar cephalostat. It became to possible to use the three dimensional cephalogram commonly in clinical bases. 1. The method of methemetical compensation of head positioning error in non-biplanar condition was evaluated with dry skull. The error of the method of first and the second trial was $0.46{\pm}1.21$, $0.33{\pm}0.90mm$, which means the error of the head positioning correction in conventional cephalogram was within clinical acceptance. 2. The reproducibility of this system for clinical application was 0.54 mm ($-2.99{\sim}2.26mm$) which defines the absolute mean difference of the first and second trial. Compare to the The landmark identification error $1.2{\pm}1.6mm$, the error of the measurement was within the range of landmark identification error. The result indicates the adequate clinical accuracy of the computation of three-dimensional coordinates by compensation of the error of the head position in ordinary non-biplanar cephalostat.

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Exploring the Possibilities of Character Education in Various Interaction-based Mentor Program: Focusing on "Becoming a Science Teacher" Activity (다양한 상호작용 기반의 멘토멘티 프로그램에서 나타난 인성 교육 가능성 탐색 -"과학 선생님 되어보기" 활동을 중심으로-)

  • Kim, Sunhee;Shin, Donghee
    • Journal of The Korean Association For Science Education
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    • v.39 no.1
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    • pp.13-33
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    • 2019
  • The purpose of this study is to clarify the possibility of the character education and the concrete implementation process in the field of science education in accordance with the social demand for character education. Based on this purpose, the researchers tried to understand the specific character elements appearing in various science learning situations and to understand the qualities of each specific character elements that can be emphasized through science learning and the aspect of expression process in related learning situations. The researchers selected 11 students from the 7th and 8th graders in Seoul and developed and applied the 'Become a Science Teacher' mentor program in 2014 and 2015. Data collection was conducted through class recordings, mentor teachers' and assistant teacher's journal, artifacts, student journals, student portfolios, class listeners' essays for science class and analyzed qualitative data collected through constant comparison method. According to the result, we extracted 11 character elements and reorganized them into 16 specific character elements revealed in various learning situations based on the relationship between each character elements. The results of the study are eight specific character elements that can be emphasized through science learning and related learning situations. The eight specific character elements are 'responsibility for teaching behavior due to hierarchy of scientific knowledge structure, communication for forming scientific concept, empathic concern based on science learning experience, cooperation for promoting rationality of inquiry method, positive perception of scientific endeavor, respect for scientists' attitudes toward research, confidence in future scientific research, persistence in trial and error'. Based on the results of this study, we proposed the research methods of character in the field of science education in the future.

Removal of Red Tide Organisms -2. Flocculation of Red Tide Organisms by Using Loess- (적조생물의 구제 -2. 황토에 의한 적조생물의 응집제거-)

  • KIM Sung-Jae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.33 no.5
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    • pp.455-462
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    • 2000
  • The objective of this study was to examine the physicochemical characteristics of coagulation reaction between loess and red tide organisms (RTO) and its feasibility, in developing a technology for the removal of RTO bloom in coastal sea. The physicochemical characteristics of loess were examined for a particle size distribution, surface characteristics by scanning electron microscope, zeta potential, and alkalinity and pH variations in sea water. Two kinds of RTO that were used in this study, Cylindrothen closterium and Skeietonema costatum, were sampled in Masan bay and were cultured in laboratory. Coagulation experiments were conducted using various concentrations of loess, RTO, and a jar tester. The supernatant and RTO culture solution were analyzed for pH, alkalinity, RTO cell number. A negative zeta potential of loess increased with increasing pH at $10^(-3)M$ NaCl solution and had -71.3 mV at pH 9.36. Loess had a positive zeta potential of +1,8 mV at pH 1.98, which resulted in a characteristic of material having an amphoteric surface charge. In NaCl and $CaCl_2$, solutions, loess had a decreasing negative zeta potential with increasing $Na^+\;and\;Ca^(+2)$ ion concentration and then didn't result in a charge reversal due to not occurring specific adsorption for $Na^+$ ion while resulted in a charge reversal due to occurring specific adsorption for $Ca^(+2)$ ion. In sea water, loess and RTO showed the similar zeta potential values of -112,1 and -9.2 mV, respectively and sea sand powder showed the highest zeta potential value of -25.7 mV in the clays. EDLs (electrical double-layers) of loess and RTO were extremely compressed due to high concentration of salts included in sea water, As a result, there didn't almost exist EDL repulsive force between loess and RTO approaching each other and then LVDW (London-yan der Waals) attractive force was always larger than EDL repulsive force to easily form a floe. Removal rates of RTO exponentially increased with increasing a loess concentration. The removal rates steeply increased until $800 mg/l$ of loess, and reached $100{\%}$ at 6,400 mg/l of loess. Removal rates of RTO exponentially increased with increasing a G-value. This indicated that mixing (i.e., collision among particles) was very important for a coagulation reaction. Loess showed the highest RTO removal rates in the clays.

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