• KIEAE Journal
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• 제16권3호
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• pp.89-94
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• 2016

Purpose: This study aimed at developing an artificial neural network (ANN) model to predict the optimal start moment of the setback temperature during the normal occupied period of a building. Method: For achieving this objective, three major steps were conducted: the development of an initial ANN model, optimization of the initial model, and performance tests of the optimized model. The development and performance testing of the ANN model were conducted through numerical simulation methods using transient systems simulation (TRNSYS) and matrix laboratory (MATLAB) software. Result: The results analysis in the development and test processes revealed that the indoor temperature, outdoor temperature, and temperature difference from the setback temperature presented strong relationship with the optimal start moment of the setback temperature; thus, these variables were used as input neurons in the ANN model. The optimal values for the number of hidden layers, number of hidden neurons, learning rate, and moment were found to be 4, 9, 0.6, and 0.9, respectively, and these values were applied to the optimized ANN model. The optimized model proved its prediction accuracy with the very storing statistical correlation between the predicted values from the ANN model and the simulated values in the TRNSYS model. Thus, the optimized model showed its potential to be applied in the control algorithm.

• 미생물학회지
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• 제8권2호
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• pp.53-64
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• 1970

In order to study ecology of microorganisms during Takju brewing, microflora changes were examined fromm the start to the sixth day of Takju fermentation in 24 hours intervals. Takju made from rice, flour and dried sweet potato in a liter volume open container at the laboratory and a sanple of Takju brewing factory were studied for their microflora and their changes during fermentationl together with a sample of Kokja. Results obtained were as follows ; 1. The followings were the identified microorganisms in Kokja. The molds ; Absidia spinosa, Aspergillus parasiticus. The yeasts ; Candida melinii, Candida Solani, Hansenula anomala. The bacteria ; Luctobacillus casei, Leuconostoc mesenteroides, Bacillus subtilis, Bacillus pumilus. 2. Torulopsis inconspicua, Lactobacillus casei, Leuconotoc mesenteroides, Bacillus subtilis, Bacillus pumilus were isolated from main mash of laboratory-made Takju samples. The yeast, Torupsis inconspicua which was not present in Kokja and, probably of a contaminant yeast, dominated the yeast flora of Takju mash of rice, flour and sweet potato of labotatory brewing. The laboratory brewing lost also always showed large population of lactic acid bacteria flora. 3. None of the wild yeasts which were present in Kokja appeared in Takju mashes. The Kokja appears to be of no use as the yeast source for Takju fermentation. Also the Kokja appears to be of not so effective amylolytic and proteolytic enzyme sources considering the microflora characteristics. Probably the major role of Kokja in Takju fermentation may be to contribute in taste formation. 4. Inoculation of Sacharomyces cerevisiae into the mash to the level of $10^7$ ml at the start of fermentation greatly changed the ecological aspects eliminating conditions of rather slow rising of natural contaminant yeast populaiton and fermentation which might give rise to prosperity of lactic acid and Bacillus bacteria that would be avoidable. 5. Examination of microflora of the large factory scale Takju fermentation showed the quite similar pattern of microflora and their changes to that of the cultured yeast-inoculated laboratory batch Takju fermentation. The cultured yeast dominated as the only predominant microflora, and the lactic acid bacteria flora were completely suppressed and aerobic bacteria, greatly. Probably this may be the regular microflora pattern of normal Takju fermentation. The role of lactic acid bacteria and aerobic bacteria in Takju fermentation may not be clear yet from this experiment alone.

• 대한화학회지
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• 제7권2호
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• pp.96-105
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• 1963

The weight decrease curves of 18 kinds of polymers have been measured by thermobalance at the same condition where temperature is increased $1^{\circ}C$ per minutes under nitrogen or air atmosphere. The curves are further differentiated to obtain rate curve of weight decrease. Those curve offer a method to compare relative thermal stability, effects of oxygen or modes of thermal degradation of polymers qualitatively. The curves could be classified into following four types: Polystyrene, polymethylmethacrylate and acetal polymer belong to the first type. Those polymers depolymerize mainly into corresponding monomers, weight decrease curves are steepy up to perfect vaporization of polymers and rate curves show a relatively sharp peak. (Type I) Polyvinyl chloride represents the second type. This polymer decomposes with splitting off of hydrogen chloride. The thermogravimetric curve rises rapidly at first, then level off at the moderate weight decrease and gradually rises. Polyvinyl acetate also belongs to this class. (Type II) The modification of the second type is represented by polyester. The curve at the early stage is less steep, the leveling off at the next stage is less clear and the final rising of the curve is steeper than the normal second type. Polyamide, polyurethane, and polycarbonate belong to this type. (Type II') The thermal decomposition of the third type polymers is more complex than that of others. Various irregular chain scissions including side chain splitting and depolymerization to monomers occur simultaneously. The weight of the polymer decreases gradually and the rate curve does not show sharp peaks. Polyvinyl alcohol and diene polymers belong to this type. (Type III) Generally, polycondensation polymers are more stable toward heat than addition polymers and polymers having aromatic nucleus show good thermal stability. Polymers having tertiary carbon atoms such as polystyrene or polypropylene and acetal resin start decomposition under airatmosphere at the temprature below $50^{\circ}C$ or more of the temperature where the polymers start decomposition under nitrogen atmosphere.

• 한국간호교육학회지
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• 제3권2호
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• pp.193-206
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• 1997

Because the oral mucositis is often inevitable in acute leukemia patients during chemotherapy, the efforts must be made to keep these leukemia patients from oral mucositis. So we tried to develop two oral care protocols for reducing the level of oral mucositis during cytotoxic therapy through literature review and our clinical experience. This quasi-experimental study was performed to compare the prohpylatic value of these oral care protocols. Thirty-nine subjects were assigned to one of three groups. The first group performed bivon-normal saline gargling protocol, the second group performed chlorhexidine gargling protocol, and the last contrast group kept traditonal gargling protocol. The Oral Assessment Guide(OAG), the Beck's perception of oral comfort were used to assess oral status and subject's oral discomfort during chemotherapy. Each subjects were observed daily from the start of the chemotherapy until Absolute Neutrophil Count (ANC) reached $1,000/mm^3$. It continued about 2-4 weeks. The data was analyzed by ANCOVA and Kruskal-Wallis one way ANOVA, chi-sqare, survival analysis. The results were as follows : The contrast group showed significantly highest mean score of the OAG and Beck's perception of oral discomfort among three groups from second week to third week. However chie-test and survial analysis showed that the incidence of severe mucositis were not significantly different among three groups. Conclusively we recommend that nurses who care acute leukmia patients use bivon-normal saline gargling protocol be careful to occur severe mucositis during chemotherapy.

• 터널과지하공간
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• 제10권4호
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• pp.497-505
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• 2000

고속도로 건설을 위한 본 조사지역과 그 주위에는 중생대 백악기의 퇴적암류와 화산암류인 응회암, 치밀 안산암 및 조립 안산암들이 분포하며, 이 암석들을 산성 및 염기성 암맥들이 관입하며 분포하고 있다. 조사지역에서의 주요 불연속 면들은 퇴적암의 충리, 절리 및 단층들로 구성되고 있다. 퇴적암의 층리의 주향은 시점구간에서는 거의 동서방향으로 발달하고 있으나 점차 북동방향으로 휘어졌다가 공구의 중간부이후에서는 거의 남북방향으로 방향이 변하고 있다. 공구내의 절리는 다양한 방향에 걸쳐 발달하며 경사각은 대체로 70도 이상으로 급경사를 이루고 있다. 퇴적암 내에서는 3 내지 4조의 절리군이 발달하나 암맥류가 분포하는 구간에서는 절리의 방향이 훨씬 분산되어 있다. 삼포단층이 공구내의 이리재를 중심으로 북동방향으로 골짜기를 따라 발달하며 구간 STA50k+600에서 STA51k+000구간에는 북서방향의 정단층이 자주 발달하고 있다. 터널굴착시 단층대를 제외한 구간에서는 불연속면들의 방향성에 따른 영향은 없을 것이지만, 층리의 간격이 좁고 많은 절리의 발달로 터널굴착시 터널벽면에서 여굴이 일어날 수 있다.

• 한국통신학회논문지
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• 제38B권8호
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• pp.597-606
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• 2013

TCP의 성능은 연결된 송신자와 수신자간의 전송 경로상의 트래픽 혼잡정도에 의해 영향을 받는다. 트래픽이 급작스럽게 증가하여 혼잡이 발생하면, 이는 데이터 전송의 장애를 유발시킬 수 있다. 데이터 전송의 장애가 발생하여 전송 패킷의 손실이 발생하면, TCP는 슬로우스타트를 수행하여 전송 속도를 낮추어 전송 경로 상의 트래픽 혼잡을 줄이고자 한다. 이동 단말이 이기종 무선 네트워크 간에 수직적 핸드오프를 하게 될 경우, TCP는 트래픽의 급격한 변화를 경험하게 되고, 이에 대해 슬로우스타트를 수행하게 된다. 본 논문에서는 수직적 핸드오프 시에 수반되는 TCP 슬로우스타트를 좀 더 효율적으로 수행하는 방법을 제안한다. 제안하는 방안은 기존의 방식과는 다르게 TCP 수신자가 슬로우스타트를 강제하는 방법이다. 이는 TCP 송신자에서 트래픽 혼잡을 경험한 후 슬로우스타트를 수행하는 기존의 방법보다 성능이 뛰어나다. 향상된 성능에 대해서는 시뮬레이션 방법으로 측정하여 성능을 검증하였다.

• Restorative Dentistry and Endodontics
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• 제39권3호
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• pp.215-219
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• 2014

Whenever endodontic therapy is performed on mandibular posterior teeth, damage to the inferior alveolar nerve or any of its branches is possible. Acute periapical infection in mandibular posterior teeth may also sometimes disturb the normal functioning of the inferior alveolar nerve. The most common clinical manifestation of these insults is the paresthesia of the inferior alveolar nerve or mental nerve paresthesia. Paresthesia usually manifests as burning, prickling, tingling, numbness, itching or any deviation from normal sensation. Altered sensation and pain in the involved areas may interfere with speaking, eating, drinking, shaving, tooth brushing and other events of social interaction which will have a disturbing impact on the patient. Paresthesia can be short term, long term or even permanent. The duration of the paresthesia depends upon the extent of the nerve damage or persistence of the etiology. Permanent paresthesia is the result of nerve trunk laceration or actual total nerve damage. Paresthesia must be treated as soon as diagnosed to have better treatment outcomes. The present paper describes a case of mental nerve paresthesia arising after the start of the endodontic therapy in left mandibular first molar which was managed successfully by conservative treatment.

• 대한소아치과학회지
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• 제24권4호
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• pp.795-804
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• 1997

Developmental dental morphological anomalies are fusion, gemination, twinning, concrescence and etc. They may cause many problems in conservative, periodontal and esthetic aspects. Fusion is a condition where two separate tooth buds unite at some stage in their development to form a bifid crown. If tooth contact occurs early, at least before the start of calcification, the two teeth may be completely unites to form a single large tooth. If tooth contact occurs after the time when a portion of the tooth crown has completed its formation, there may be union of the roots only. In fusion the dentin is always confluent. Fusion teeth is more common in the deciduous than in the permanent dentition. Fused teeth are relatively rare, and are mostly mandibular anterior teeth. Fusion of normal and supernumerary teeth or between normal teeth may occurs. The exact etiology factor of fusion is unknown, but genetic and environmental factors seems to be related. A variety of complications and subsequent treatments have been suggested on this teeth. Periodontal conditions may arise due to a groove formed at the line of fusion of the two teeth. Crowding or Protrusion with potential for malocclusion or delayed eruption of adjacent teeth. Fusion teeth appear in the anterior region, they usually cause esthetic problems. Treatments vary depending on the problem, the location, and the extent of fusion. Treatment of fused teeth has been reported from endodontic, orthodontic, periodontic, surgical and multidisciplinary. This report presents the esthetic improvements by separation of two clinical crowns. Bone reduction or endodontic treatments are not required.

• Steel and Composite Structures
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• 제42권4호
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• pp.501-511
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• 2022

Earthquake Resistant Design Philosophy seeks (a) no damage, (b) no significant structural damage, and (c) significant structural damage but no collapse of normal buildings, under minor, moderate and severe levels of earthquake shaking, respectively. A procedure is proposed for seismic design of low-rise reinforced concrete special moment frame buildings, which is consistent with this philosophy; buildings are designed to be ductile through appropriate sizing and reinforcement detailing, such that they resist severe level of earthquake shaking without collapse. Nonlinear analyses of study buildings are used to determine quantitatively (a) ranges of design parameters required to assure the required deformability in normal buildings to resist the severe level of earthquake shaking, (b) four specific limit states that represent the start of different structural damage states, and (c) levels of minor and moderate earthquake shakings stated in the philosophy along with an extreme level of earthquake shaking associated with the structural damage state of no collapse. The four limits of structural damage states and the three levels of earthquake shaking identified are shown to be consistent with the performance-based design guidelines available in literature. Finally, nonlinear analyses results are used to confirm the efficacy of the proposed procedure.

• Clinical and Experimental Pediatrics
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• 제51권8호
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• pp.804-811
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• 2008

목 적 : 최근 소아비만이 증가 추세에 있으며, 소아비만은 성인비만으로 이행할 가능성이 높다. 그러므로 소아기 부터 비만의 예방이 중요하다. 이에 본 연구는 학령전기 소아비만에 영향을 주는 영유아기 인자를 알아보고자 하였다. 방 법 : 2007년 10월 부산에 위치한 어린이집과 왈레스기념 침례병원 외래를 방문한 만 3세 이상 5세 미만 아동 350명을 대상으로 하여 그들의 부모에게 설문조사를 하였고, 그중 223명이 최종 분석에 사용되었다. 아동들의 현재 신장과 체중에 대한 신체계측은 어린이집과 병원에서 전자체중계와 신장계를 이용하여 측정하였으며, 체질량지수를 산출하여 85백분위수 이상인 경우 과체중위험 군, 85백분위수 미만인 경우 정상체중군으로 분류하였다. 설문조사를 통해 부모의 일반적인 특성(어머니 학력, 직업유무, 부모의 비만 여부), 출생체중, 수유 관련 내용(수유방식, 밤중 수유 지속 기간, 이유식 시작 시기), 양육자에 대한 정보를 얻었다. 결 과 : 과체중위험 군에 속하는 소아는 68명(30.5%)이었고, 정상체중군에 속하는 소아는 155명(69.5%)이었다. 분유를 수유한 경우가 모유를 수유한 경우에 비해 과체중이상인 경우가 11.3배 높게 나타났고(P<0.05), 출생 후 첫 6개월간 빠른 체중 증가가 학령전기 소아 과체중위험 군과 연관이 있는 것으로 나타났다(P<0.05). 과체중위험 군의 어머니의 체질량지수($22.2{\pm}2.4kg/m^2$)가 정상체중군($20.6{\pm}2.3kg/m^2$)에 비해서 유의하게 높았다(P<0.05). 아버지의 체질량지수(P=0.658), 어머니 학력(P=0.134), 직업유무(P=0.396), 밤중 수유 지속 기간(P=0.530), 이유식 시작 시기(P=0.078), 양육자(P=0.881), 6-12개월간 빠른 체중 증가(P=0.628), 출생체중(P=0.598)은 비만과 유의한 관련이 없었다. 결 론 : 소아비만이 될 영유아기 인자를 가지고 있는 자녀를 둔 가족들에게 영유아기에 초점을 맞춘 비만 예방 프로그램을 적극 제시해 주어, 영유아기 부터 비만의 위험을 예방하는 것이 중요할 것으로 사료된다.