• 생물환경조절학회지
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• 제26권4호
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• pp.368-377
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• 2017

본 연구는 최근에 도입된 원통형 종이포트 묘에 대한 현장 활용가능성을 검토하고자 기존의 프러그 묘를 대조구로 하여 몇가지 육묘조건에 따른 묘의 생육 차이를 분석하고, 정식 후 수량을 비교하였다. 전주 유리온실에서 수행된 육묘 실험에서는 묘의 생육은 프러그 트레이 50공에서 지속 시비한 처리에서 생육량이 가장 많았다. 생육은 육묘 상자의 구멍에 채우는 상토량에 따라 영향을 받으며, 육묘 상자 보다는 시비 처리에 따른 차이가 더 컸다. 공시한 '청양', '대권선언', '롱그린맛' 품종 모두 같은 양상을 보였다. 육묘 후 비닐하우스와 노지에 심어서 뿌리 발달과 수량을 조사한 결과, 비닐하우스 재배 시 '청양' 품종의 뿌리 내림은 종이포트묘와 프러그묘 간에 차이가 없었으며, 공시한 3 품종 모두 최종 누적수량의 차이는 없었다. 전주 지역 노지재배에서는 '청양'은 종이포트묘가, '대권선언'과 '롱그린맛'은 프러그묘가 누적수량이 많았다. 영양 지역에서 '대권선언' 품종은 종이포트묘와 프러그묘 간에 수량 차이는 없었다. 결론적으로 육묘 처리 조건에 따른 원통형 종이포트 고추묘의 생육의 변화는 기존의 프러그묘와 같은 양상이며, 정식 후 재배조건과 품종에 따른 미미한 차이는 있었으나 전반적으로 수량차이는 없는 것으로 나타나 앞으로 원통형 종이포트 고추 묘에 대한 활용가능성은 높을 것으로 판단되었다.

• 한국정밀공학회지
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• 제16권1호통권94호
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• pp.227-237
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• 1999

As the interface bonding phenomenon between the matrix and the reinforcements has a large effect on the mechanical properties of MMCs, a sugestion of the strength analysis technique considering the residual stress and the interface bonding phenomenon is very important for the design of pans and the estimation of fatigue behavior. In this paper the three dimensional finite element anaysis is performed during the elasto-plastic deformation of the particulate reinforced metal matrix composites. It was analyzed with the volume fractions in view of microscale. Bonding strength. interface separation and matrix void growth between the matrix and the reinforcements will be predicted on deformation under tensile loading. An interface seperation is estimated by the fracture criterion which is a critical value of generalized plastic work per unit volume. The shape of the reinforcement is assumed to be a perfect sphere. And the type of the reinforcement distribution is assumed as FCC array. The thermal residual stress in MMCs is induced by the heat treatment. It is included at the simulation as an initial residual stress. The element birth and death method of the ANSYS program is used for the estimation of the interface bonding strength, void generation and propagation. It is assumed that the fracture in the matrix region begin to occur under the external loading when the plastic work per unit volume is equal to the critical value. The fracture strain will be defined. The experimental data of the extruded $SiC_p$>/606l Al composites are compared with the theoretical results.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제22권2호
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• pp.254-261
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• 2000

Since callus distraction technique was applied clinically for the correction of dentofacial deformity to the patients with hemifacial dysplasia by McCarthy in 1992, many surgeons have tried to apply this method to the maxillofacial region. But this technique has some drawbacks. One of the disadvantages of this technique is extensive scar formation in the facial area, which is a sequelae of extraoral approach for supraperiosteal dissection of the periosteum overlying the mandible. Recently, we have made an effort to perform this technique through intraoral approaches to prevent scar formation on the submandibular area and modified the design of the osteotomy, that is step osteotomy technique, to increase the raw bone surface on both osteotomized segments. The rationale for the application of this step osteotomy technique is to increase the amount of regenerated bone and the length of distraction, to avoid damage of inferior alveolar neurovascular bundle, and to increase initial stability of the splitted segments. Step osteotomy procedure can be done with fine micro-osteotomy saw through subperiosteal tunneling. Extraoral pins should be inserted before making the osteotomy. Since 1994 we have applied this technique at 8 sites In 5 patients with mandibular deficiencies: 2 cases of hemifacial microsomia, 1 case of developmental facial asymmetry and 2 cases of mandibular bony defect. Mandibular elongation have been achieved from 12 to 20mm in length. 1 out of 8 site, we experienced non-union in the case of mandibular body defect. Some skeletal relapse and growth retardation phenomenon have been observed in some cases with the longest follow-up of 48 months.

• Asian Pacific Journal of Cancer Prevention
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• 제16권15호
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• pp.6541-6544
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• 2015

Background: Laryngeal malignancy is a common malignancy of the head and neck region. Affected patients usually present with features that are characteristic of certain subsites. The larynx is oncologically divided into three: supraglottis, glottis and subglottis. Studies from Western countries have shown that the glottis is the commonest subsite to harbour laryngeal malignancy. However, the supraglottis has been reported to be the commonest subsite in developing countries, including examples in the Indian subcontinent. To our knowledge, no study has been carried out in western Nepal about the epidemiology of laryngeal cancer to date. The purpose of this study was to analyse the epidemiology of laryngeal cancer in relation to its risk factors, age distribution,and preferred subsites and to see if there is any recent change in the subsite wise distribution of laryngeal malignancy in western Nepal. Materials and Methods: Patients of all ages and both sexes with suspected laryngeal malignancy were enrolled in the initial study. Detailed history taking and clinical examination was performed to find out the involved subsite in relation to the clinical features. Direct laryngoscopy was performed to further confirm the subsite and to take biopsy from the growth under general anesthesia. After confirmation of malignancy from the biopsy report, patients were finally included in the study. Data were analysed and observations were made to find out the distribution of laryngeal malignancy in different subsites. Results: The supraglottic larynx was the commonest subsite to harbor laryngeal malignancy. Smoking and alcohol were found to be the common risk factors. The mean age of the patients was in their sixties. Conclusions: Laryngeal malignancy is common in elderly individuals. Supraglottic laryngeal malignancy is the commonest laryngeal malignancy in people who smoke and drink alcohol in Nepal. Avoidance of alcohol use and smoking will be a milestone to reduce the incidence of laryngeal cancers and associated mortality.

• Journal of Forest and Environmental Science
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• 제34권4호
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• pp.338-351
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• 2018

This study was conducted in a long-term experimental forest in the central hardwoods region of southwestern Michigan to retrospectively examine the role of past forest management practices and climate on red oak (Quercus rubra L.) productivity. Initially, in 1971, plots within the experimental forest were treated separately with a clearcut and shelterwood regeneration harvest in an attempt to increase red oak regeneration. From 1987-1989, a new study was initiated within a portion of the clearcut and shelterwood plots to evaluate the effectiveness of additional oak crop tree release using mechanical and chemical applications. Cumulative diameter and mortality rates of 719 red oaks were monitored across the four silvicultural treatments: Clearcut-A (clearcut without additional release treatment), Clearcut-B (clearcut with additional release treatment), Shelterwood-A (shelterwood without additional release), and Shelterwood-B (shelterwood with additional release) plus an untreated control. Increment cores were obtained from red oak trees and neighboring competitor species. Tree-ring analyses (dendrochronology) were applied to examine the effect of these silvicultural treatments and climatic factors (temperature and precipitation) on red oak productivity. The results indicated that crop tree release following a clearcut or shelterwood harvest reduced mortality rates and thus increased survival of red oak. Red oak in control plots or plots only receiving the initial regeneration harvesting treatment and no additional competition release were negatively affected by climatic stress, which included summer moisture stress. In contrast, red oak in plots that received the competition release treatment from shade tolerant tree species not only had higher tree level productivity (i.e., tree basal area) and lower mortality rates, but were also relatively more resilient to climatic stress by showing limited or no associations between climate and growth.

• 한국자기학회지
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• 제12권4호
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• pp.132-136
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• 2002

유리기관 위에 이온 빔 증착(ion beam deposition ; IBD)법으로 제작한 버퍼층(buffer layer) Si의 두께에 따른 ［NiFe/FeMn/NiFe］3층박막의 결정성과 교환결합세기(exchange bias field ; H$_{ex}$)를 조사하였다. 버퍼층 Si는 NiFe층을 fcc(111)로 매우 우세하게 초기에 결정성장 시켰다. Si/NiFe 위의 증착된 FeMn층은 ${\gamma}$-fcc(111)구조로 성장함에 따라 안정되고 큰 H$_{ex}$를 가졌고, 버퍼 110 Oe로 거의 일정하였으며, 상부 FeMn/NiFe 이중구조의 H$_{ex}$는 300 Oe까지 증가하였다. 버퍼층이 Ta일 경우와 비교해서 Si일 때 H$_{ex}$와 결정성이 향상되었다.이 향상되었다.

• 에너지공학
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• 제2권2호
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• pp.179-186
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• 1993

평판형 태양열 집열기에 적용되는 열파이프는 증발부에 상대적인 낮은 열유속으로 길이가 길고 가느다란 형상을 갖는다. 이러한 열파이프는 증발부의 하단부에서 액체 Pool이 형성하는 경향이 있다. 그리고 이 Pool에서 과열, 급속한 기포의 생성, 기포의 폭발적인 성장과정과 Flooding 등의 복잡한 증발과 유체 역학적 현상이 발생한다. 본 논문에서는 4개의 열파이프와 3개의 열사이폰을 이용하여 주 설계변수인 작동유체의 충전량과 위크의 설치 영역을 조절함으로써 이러한 문제를 해결하도록 하였다. 이에 대한 결과들은 다음과 같이 요약할 수 있다$^{1)}$ . 열파이프의 유효 열전도도는 단열부와 응축부에 위크를 제거함으로써 상당히 개선할 수 있었다$^{2)}$ .액체의 충전량은 위크를 적실수 있는 양보다 약 40%정도 증가시켜야 한다$_{3)}$ . 증발부에서 위크는 핵비 등의 단속적 발생에 의한 불안정한 작동과 포기 시동과정에서 응답시간을 줄이는데 유용한 효과를 갖는다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제40권
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• pp.37.1-37.7
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• 2018

Background: Fibrous dysplasia (FD) is characterized by the replacement of normal bone by abnormal fibro-osseous connective tissue and typically treated with surgical contouring of the dysplastic bone. When dysplastic lesions involve occlusion, not only is surgical debulking needed, orthognathic surgery for correction of dentofacial deformity is mandatory. However, the long-term stability of osteotomized, dysplastic bone segments is a major concern because of insufficient screw-to-bone engagement during surgery and the risk of FD lesion re-growth. Case presentation: This case report reviewed two patients with non-syndromic FD that presented with maxillary occlusal canting and facial asymmetry. Le Fort I osteotomy with recontouring of the dysplastic zygomaticomaxillary region had been performed. The stability of osseous segments were favorable. However, dysplastic, newly formed bone covered the previous plate fixation site and mild bony expansion was observed, which did not influence the facial profile. Including the current cases, 15 cases of orthognathic surgery for FD with dentition have been reported in the literature. Conclusion: The results showed that osteotomy did not appear to significantly reduce the long-term stability of the initial fixation insufficiency of the screw to the dysplastic bone. However, based on our results and those of the others, long-term follow-up and monitoring are needed, even in cases where the osteotomized segment shows stable results.

• 한국임상수의학회지
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• 제31권6호
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• pp.544-546
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• 2014

식욕 부진과 복부 팽만을 보인 1.5살령의 암컷 토끼가 방사선 검사와 초음파 검사에서 자궁 확장 소견이 확인되었고, 이틀 후 쇼크로 응급 내원하여 탐색적 개복술을 실시하였다. 양측 자궁각이 자궁 경부에서 염전되어 있었고, 양측 자궁각의 내용물에 대한 배양 검사 결과 우측 자궁각은 자궁수종, 좌측 자궁각은 자궁축농증이 발생한 것으로 진단되었다. 질병의 발생 기전에 대해 정확하게 설명하기 어렵지만, 복부 팽만이 4개월간 지속되다가 갑자기 토끼 상태가 악화되어 쇼크로 진행된 점으로 미루어 초기에 자궁수종이 발생하였다가 감염 및 자궁 내 다량의 내용물로 인한 자궁염전이 급성으로 발생한 것으로 판단되었다. 본 증례는 각각의 자궁각에 자궁수종과 자궁축농증이 별도로 발생하고 염전이 동반된 매우 드문 예이다.

• 한국재료학회지
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• 제29권9호
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• pp.553-558
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• 2019

$Cu_2ZnSn(S,Se)_4(CZTSSe)$ thin film solar cells areone of the most promising candidates for photovoltaic devices due to their earth-abundant composition, high absorption coefficient and appropriate band gap. The sputtering process is the main challenge to achieving high efficiency of CZTSSe solar cells for industrialization. In this study, we fabricated CZTSSe absorbers on Mo coated soda lime glass using different pressures during the annealing process. As an environmental strategy, the annealing process is performed with S and Se powder, without any toxic $H_2Se$ and/or $H_2S$ gases. Because CZTSSe thin films have a very narrow stable phase region, it is important to control the condition of the annealing process to achieve high efficiency of the solar cell. To identify the effect of process pressure during the sulfo-selenization, we experiment with varying initial pressure from 600 Torr to 800 Torr. We fabricate a CZTSSe thin film solar cell with 8.24 % efficiency, with 435 mV for open circuit voltage($V_{OC}$) and $36.98mA/cm^2$ for short circuit current density($J_{SC}$), under a highest process pressure of 800 Torr.