얇은 도핑조절 a-Si:H초격자에서 지속 광전기 전도도

康聖洙,梁承勳,李原鎭,金英鳳,孔維庠,朴相俊,崔時永 慶北大學校 1990 論文集 Vol.49 No.-

Very large PPC effect(σ_ppc/σ_A=10^5) in doping-modulated npnp a-Si: H superlattices could be obtained. B and P atoms, respectively, diffuse and so some parts compensated. Therefore, annealing activation energy of E_a=0.67eV is larger than one of reference n-type sample of E_a=0.26eV and annealing dark conductivity of σ_A=4×10^-[ohm cm]^-1 is lower than that of n-type reference sample of σ_A=2×10 exp (4)[ohm cm]^-1. From this results, very large PPC relatively have obtained. In this paper, we have observed that PPC effect depends on temperature and exposure time. On the basis of the experimental results, we discuss the existing models.

초등학교 과학 수업에서 개념도 활용의 효과

강석진,이유영,고한중,전경문,노태희 한국초등과학교육학회 2004 초등과학교육 Vol.23 No.1

In this study, we investigated the effects of using concept mapping as an instructional tool on 4th graders' achievement, science learning motivation, and attitude toward science classes. T재 classes (38 students) from an elementary school were respectively assigned to a control group and a treatment group. Students were taught about "expansion of matter by heat" and "heat transfer". These topics were chosen because they require students to understand more concepts as well as relationships among them. A science learning motivation test and an attitude toward science classes test were administered as pretests. A researcher-made achievement test, the science learning motivation test, and the attitude toward science classes test were administered as posttests. The results indicated that using concept mapping in 4th-grade science classes was not significantly effective in improving students' achievement though a statistically significant positive effect was found in the subcategory of knowledge. No statistically significant effect of using concept mapping was found in the scores of the science learning motivation test and the attitude toward science classes test. Educational implications are discussed.

정어리 어분의 지질함량에 따른 저장안정성

유병진,이강호,정인학 江陵大學校東海岸地域硏究所 1992 東海岸硏究 Vol.3 No.1

우리나라에서 80년대 이후 연간 약 13만∼18만톤 어획되는 가장 중요한 수산자원의 하나인 정어리는 그 자체의 여러가지 원인으로 식품가공소재로서의 이용이 제한되고 주로 어분 및 어유의 원료로 이용되고 있다. 그러나 정어리 어분은 지방함량이 높고 또한 함유지질의 구성지방산도 고도불포화지방산의 비율이 높아 산화로 인한 품질의 악변이 정어리어분의 이용에 큰 제약이 되고 있다. 2단 자숙으로 지질함량을 대폭 감소시킨 어분과 기존의 어분과의 저장 중의 품질변화를 실험한 결과를 요약하면 아래와 같다. 1. 2단 자숙으로 지질함량을 1단 가열로 제조한 어분의 지질함량 11.7%에서 2.51%로 감소시켰다. 2. 1단 가열로 제조된 어분의 지질조성은 비극성이 64.2%, 극성이 35.8%인데 비하여 2단 가열로 제조한 경우는 극성이 60.7%, 비극성이 39.2%로 오히려 극성지질의 함량이 높았다. 3. 구성지방산은 ??이 주요 구성지방산들이었으며 1단 가열로 제조된 어분의 경우 ??이 극성지질에서 24.1%, 비극성지질에서 8.7%었으나 2단 가열로 제조된 경우 21.3%와 10.6%로 다소 열에 의해 파괴된 것으로 나타났다. 4. 지질의 산패는 AV, POV, COV가 비슷한 경향을 보이며 2단 가열로 지질의 함량이 줄어든 시료어분에서 온도가 높을수록 보다 급속히 진행되었으며 5℃의 저온에서도 지질의 산패는 억제되지 않았다. TBA값은 지질함량이 많은 1단 자숙으로 제조된 어분에서 10.2가 2단 가열로 지질함량이 낮은 경우의 어분에서의 5.2보다 약 2배 높은 값을 보였으며 이후의 증가는 저장온도가 높을수록 신속히 진행되었으나 2단 자숙으로 제조된 어분에서 5℃와 상온에서 저장하였을 겨우 상당히 안정한 값을 저장 50일 경까지 보였다. 5. 수용성 갈변반응은 2단 자숙한 경우가 흡광도로 0.17로서 1단 자숙한 경우의 0.08보다 높았으나 1단 자숙의 경우 저장 중에 저장온도에 관계없이 모두 일정한 속도로 증가하였으나 2단 자숙하여 제조한 어분에서는 5℃로 저장했을때 상당히 억제되었다. 지용성 갈변은 1단 가열로 제조한 경우가 오히려 높은 값을 보여 2단 가열의 0.42보다 높은 0.94의 약 2배이상의 값을 보였으며 전체적으로 지용성 갈변이 수용성 갈변보다 우세하여 어분의 품질저하에 주도적 역할을 하였다. The effects of lipids elimination through conventional steaming method(one step steaming) or new method(two steps steaming) on the storage stability and quality deterioration of sardine fish meals were investigated by means of lipids oxidation, fatty acids composition and browning during storage at 50℃, 30℃, 5℃ and room temperature. Lipids content, 11.70% in the fish meals made by one step steaming was decreased to 2.51% through one more steps of steaming. In conventional fish meal, nonpolar and polar lipids were composed 64.2%, 35.8% respectively, but the composition was reversed to 39.2% and 60.78% in two step steamed fish meal. Among the principal fatty acids, ?? of the sardine fish meals, ?? was charged 24.1% in polar and 8.7% in non-polar lipid of one step steamed fish meal, and the values were decreased to 21.3%, 10.6% in two step steamed meal respectively. The lipid oxidation in two step steamed fish meal was enhanced more intensely than in one step steamed fish meal according to results of POV, COV and AV tests during storage. But according to TBA test, the quality and oxidative stability has steaded better effectively in two step steamed fish meal than in one step steamed fish meal. Hydrophilic browning reaction was predominant in two step steamed meal, but lipophilic browning become predominant in one step steamed fish meal. For all that lipophilic browning gained predominating influence with 3∼10 times over hydrophilic browning in sardine fish meal.

누두흉 환자에서 Nuss 금속막대 제거 전 · 후 폐 역학 변화

강규식,백남순,김천숙,안기량,권진형,김지은,유시현 순천향의학연구소 2003 Journal of Soonchunhyang Medical Science Vol.9 No.1

Nuss operation is one of the surgical procedure for pectus excavatum and it's method is the insertion of convex steel bar under the sternum through small bilateral thoracic incision. As the patients is growing, the thorax can be compressed gradually by steel bar. So Nuss bar needs to be removed two years after Nuss operation. This study was undertaken to assess the effect on the repiratory mechanics before and after the removal of the Nuss bar. Twenty patients with previous Nuss operation were allocated for the removal of Nuss bar. Lung mechanics (dynamic lung compliance, static lung compliance, and airway resistance), hemodynamic change (heart rate, systolic pressure, and diastolic pressure), and pulmonary gas exchange (arterial oxygen tension, arterial carbon dioxide tension, pulse oximeter saturation, and end tidal carbon dioxide tension) were measured before and after removal of Nuss bar. Respiratory mechanics (dynamic and static lung compliance, inspiratory airway resistance), pulmonary gas exchange and hemodynamic parameter were unchanged before and after the removal of Nuss bar. We concluded that lung mechanics were not changed before and after the removal of Nuss bar in the patients with pectus excavatum and the 95% patients were satisfied with operation.

반복적인 급성 신부전을 유발한 호산구성 장염 1 예

정혜진;김현태;김유선;정현걸;강윤경;문정섭 인제대학교 2011 仁濟醫學 Vol.32 No.-

Eosinophilic gastroenteritis is a rare disorder of unknown etiology characterized by presence of gastrointestinal symptoms, eosinophilic infiltratio n of one or more parts of gastrointestinal tract without involvement of other organs and absence of parasitic infestation. The clinical presentation depends on the extents and depths of eosinophilic infiltration. Mucosal involvement may result in abdominal pain, nausea, vomiting, diarrhea and weight loss. We report a case of eosinophilic enterocolitis in a 55-year-old female presented with abdominal pain and watery diarrhea resulting in recurrent acute renal failure.

폴리에스테르 섬유 감량시스템용 프로세서 타이트레이터 개발

조진호,이흥락,이종현,김명남,구성모,김무영,진경찬,유병희,강민수,김국진 경북대학교 센서기술연구소 1993 연차보고서 Vol.1993 No.-

폴리에스테르 섬유 감량시스템의 제어를 위해서는 처리조 내에서 감량되는 섬유가 목표 감량치에 도달했는지를 판단해 주는 장치가 필요하다. 본 연구에서는 가성소다용액의 초농도 및 섬유 감량 정도의 정확한 측정과 감량 종료시간의 산출 및 이에 따른 종료신호를 발생할 수 있는 폴리에스테르 섬유 감량기 전용의 자동적정장치를 개발하였다. To control caustic soda treatment system for the polyester fabric reduction, we need the device to determine that the fabric has been arrived target reduction value. In this study, we develope an automatic process titrator for the caustic soda treatment system. Major functions of the target titrating system are accurate measurements of the caustic soda concentration and then producing the end point signal for caustic soda treatment system.

EM알고리즘에 의한 다변량 혼합정규분포하의 분류방법

황강진,박정욱,유희경 三陟大學校 2000 論文集 Vol.33 No.1

Cluster analysis is a technique for unsuoervised classification which the group information is not available. General cluster analysis uses euclidean distance as a measure of group similarity. However, it might cause some problem such as ignoring the pattern of the groups which is characterized by the relationships between variables. Hence general clustering method can lead to misclassification problem. It is worth considering mixture distributions for the classification. That is each cluster or group has its own distribution and they are mixed together. The main purpose here is to find which group has the maximum probability for each observation to be classified. EM algorithm is a useful technique to find the maximum likelifood estimator from incomplete data. In this paper, we assume that each group follows multivariate normal distribution and consider that the given data are incomplete because there is not the group information. We introduce new variable which indicates the group information. Then the augmented data becomes complete data. EM algorithm is used to estimated conditional expection for group information variable from the complete likelifood function. The effect of EM algorithm is compared to k-means clustering by misclassification probability.

다양한 철강용 RFID태그 안테나

이상곤,강진욱,정유정,김신환 대구대학교 정보통신연구소 2006 情報通信硏究 Vol.4 No.1

攪伴機에 依한 土狀黑鉛의 球狀凝集

金燦國,姜大雨,金裕鎭 동아대학교 공과대학 부설 한국자원개발연구소 1984 硏究報告 Vol.8 No.2

This study has been carried out to determine the effects of bridging liquid concentrations, agitation time, agitation speed, pulp density, and viscosities of the bridging liquid on growth of the agglomerates by agitating the suspension with bridging liquid which preferentially wets the carbon particles. The results of this experiment are as follows : 1) As larger amounts of bridging liquid are used, the size of agglomerates are increased until the end of the capillary region of pore filling after which there is an excess of bridging liquid. 2) At the initial stage of the agitation, the size of agglomerates are increased while after a certain agitation period, the size of agglomerates are decreased because destructive force is increased by frequency of collisions between the agglomerates themselves and their adhesion to the walls of the vessel. 3) The diameter of the final agglomerates are determined by a balance between destructive and cohesive forces acting on agglomerates.

갑상선 초음파검진의 유용성

배오근,김재권,강명순,조영익,김임봉,신유진,임성규,서민호 한국건강관리협회 2000 건협 Report Vol.3 No.-