베이지안 학습을 이용한 문서의 자동분류

김진상,신양규,Kim, Jin-Sang,Shin, Yang-Kyu 한국데이터정보과학회 2000 한국데이터정보과학회지 Vol.11 No.1

As the number of online documents increases enormously with the expansion of information technology, the importance of automatic document classification is greatly enlarged. In this paper, an automatic document classification method is investigated and applied to UseNet 20 newsgroup articles to test its efficacy. The classification system uses Naive Bayes classification algorithm and the experimental result shows that a randomly selected newsgroup arcicle can be classified into its own category over 77% accuracy. 정보통신기술의 비약적인 발전은 온라인으로 생성되는 전자문서의 양을 폭발적으로 증가시키고 있다. 따라서 수동으로 문서를 분류하던 종래의 방법 대신 문서의 자동분유 기술 개발이 특별히 요구되고 있다. 본 논문에서는 베이지안 학습 기법을 이용하여 문서를 자동으로 분류하는 방법을 연구하고, 20개의 유즈넷 뉴스그룹 문서들을 분류하도록 시험하였다. 사용한 알고리즘은 Naive Bayes Classifier이며, 구현한 시스템을 이용해 유즈넷 문서를 대상으로 자동분류를 실험한 결과 분류의 정확률이 약 77%로 나타났다.

나노구조체 열전 에너지 변환 소재

김진상,Kim, Jin-Sang 한국전기전자재료학회 2007 전기전자재료 Vol.20 No.12

기니픽에서 갑상선, 간 및 신기능에 미치는 납과 selenium의 상호관계

김진상,강형섭,강창원,Kim, Jin-sang,Kang, Hyung-sub,Kang, Chang-won 대한수의학회 1996 大韓獸醫學會誌 Vol.36 No.3

This study was designed to examine the involvement of lead in function of target organ, and the protective effect of selenium in lead-treated guinea pigs for 8 weeks. The effects of exposure to 0.5% lead acetate(lead) and/or 4ppm sodium selenite(selenium) in feed on serveral aspects were evaluated by measuring thyroid stimulating hormone(TSH), triiodothyronine($T_3$), thyroxine($T_4$), serum biochemical activities, organ weights, and serum and organ lead concentrations in growing animals. The many indicators of endocrine function(TSH, $T_3$, and $T_4$ in serum), enzyme and biochemical activities(${\alpha}$-glutamyltranspeptidase, alkaline phosphatase, lactate dehydrogenase, triglyceride, creatinine, $Ca^{2+}$ in serum), and organ weights(kidney, spleen and testis) were correlated with lead exposure or showed significantly different mean values between the exposed and controls. These changes on some aspects were reversed by combination-fed of selenium, but did not statistically significant. The organ(kidney, liver, spleen, testis and brain) and serum lead concentrations of lead-fed group were clearly higher than that of controls. Selenium supplementation resulted in a significant protection against lead accumulation in liver and testis. These results suggest that lead can cause a toxic effect on several organ and that selenium seems to has a protective effect on specific reaction by lead-induced organic function toxicity.

Guinea pig에서 alcohol과 paraquat에 의한 갑상선 독성에 미치는 selenium의 방어 효과

김진상,강형섭,Kim, Jin-sang,Kang, Hyung-sub 대한수의학회 1996 大韓獸醫學會誌 Vol.36 No.1

This study examined the effect of alcohol(AL) and/or paraquat(PQ) on serum TSH, thyroid hormones and enzyme activities, and the protective effect of selenium(SE) againse alcohol and/or paraquat-induced thyroid toxicity in guinea pigs. The experomental group consisted of control, 15% alcohol(AL), 4ppm sodium selentite(SE), 200ppm paraquat(PQ), AL+PQ, AL+SE, PQ+SE and AL+PQ+SE mixed in drinking water-fed guinea pigs for 4 weeks. The morphological changes of thyroid gland were studies on paraffin-embedded sections stained with H-E stain. Body weight losses, high serum concentration in TSH and cholesterol, and low values on triiodothyronine($T_3$), thyrozine($T_4$), free $T_4$ and alkaline phosophatase(ALP) were produced in the groups fed AL and/or PQ. We also noted that AL+PQ-fed group was marked increase in serum TSH. In AL or AL+PQ-fed groups when cpmpared to control group had increased the ratio of thyroid weight to body weight(ratio Twt/Bwt), whereas the ratio Twt/Bwt was decresed in SE or PQ-fed groups. However, the serum TSH, $T_3$,$T_4$ free $T_4$ and cholesterol values, and the ratio Twt/Bwt were reversed in groups given the combination of SE, compared with AL and/or Pq-fed groups, also ALP values were reversed in groups given the combination of SE, compared with AL or AL+PQ-fed groups. In microscope, morphological changes showed a remarkable between the AL or PQ-fed group and controls. In AL+PQ+SE-fed guinca pig, follicular colloid is high density in thyroid follicle and increased in connective tissue around the thyroid cells, and thyroidal epithelia were composed of cuboidal or columnar epithelium. The indicated that the morphological changes of thyroid were direct action in the thyroid cell. The results of this study confirmed that the toxic effect of AL or PQ on thyroid occur independently of changes in liver function, and that SE confers marked protection against AL or PQ-induced thyroid toxicity.

고령에 따른 흰쥐 시상하부 oxytocin 분비세포의 형태적 변화에 대한 면역조직화학적 연구

김진상,이성준,Kim, Jin-sang,Yi, Sung-joon 대한수의학회 1995 大韓獸醫學會誌 Vol.35 No.1

This study was carried out to investigate the morphological changes of the oxytocin secreting neurons in age-related rat hypothalamus by means of immunohistochemistry. The experimental group was 20 aged female rats (Sprague-Dawley, 25~30 months), and the control group was 10 adult female rats (10 months). All animals were perfused transcardially with 4% paraformaldehyde-lysine-periocdate(PLP), and serial transverse brain sections($30{\mu}m$) were prepared by means of cryotome, and were stained with rabbit anti-oxytocin antisera immunohistochemically, using the free floating method and avidin-viotin peroxidase complex. The results were as followings. 1. The immunostained oxytocin secreting neurons were located at the paraventricular nucleus and supraoptic nucleus of age-related rat hypothalamus chiefly. 2. The numbers of oxytocin secreting neurons decreased at the paraventricular nucleus and supraoptic nucleus of age-related rat hypothalamus(p<0.01) 3. The oxytocin secreting neurons of age-related rat hypothalamus immunostained less than those of the adult rat hypothalamus, and the paraventricular nucleus immunostained greater than supraoptic nucleus in age-related rat. 4. The numbers and expansion of dendrite and axonal varicosities decreased in the age-related rat hypothalamus greatly.

기니픽 유두근에서 α₁-adrenoceptor 자극에 의한 세포내 pH와 Na⁺ 증가는 Na⁺-H⁺ 교환기를 경유

김진상,Kim, Jin-sang 대한수의학회 1995 大韓獸醫學會誌 Vol.35 No.2

The effect of ${\alpha}_1$-adrenoceptor(${\alpha}_1$-AR) stimulation on intracellular pH($pH_i$), $Na^+$ activity($a_{Na}{^i}$) and contractility were investigated in isolated papillary muscles of euthyroid or hyperthyroid guinea pig with conventional microelectrode, $Na^+$ or $H^+$-selective microelectrodes, and tension transducer. Stimulation of the ${\alpha}_1$-AR by phenylephrine produced a decrease in $a_{Na}{^i}$ in euthyroid preparations. This decrease in $a_{Na}{^i}$ was abolished in presence of PKC activator, phorbol dibutyrate, and increased contrary to decrease. Phenylephrine also increased $a_{Na}{^i}$ in hyperthyroid ones. However, phenylrephtine produced an increase in $pH_i$ in both euthyroid and hyperthyroid ones. These changes were blocked by prazosin, an antagonist of ${\alpha}_1$-AR. These findings suggest that the changes in $a_{Na}{^i}$ and $pH_i$ are mediated by a stimulation of $Na^+-H^+$ exchange via ${\alpha}_1$-AR stimulation. This study focused on the increase in $a_{Na}{^i}$, $pH_i$ and contractility. The increase in $pH_i$ was blocked by amiloride or EIPA, $Na^+-H^+$ exchange inhibitors. Therefore, the increase in $a_{Na}{^i}$ and $pH_i$ mediated by ${\alpha}_1$-AR appeared to be due to an influx of $Na^+$ and a reduction of $H^+$ through $Na^+-H^+$ exchange. This study also revealed that the increase in $pH_i$ and $a_{Na}{^i}$ might be related to the sustained positive inotropic response. The $a_{Na}{^i}$ increase may contribute to the intracellular $Ca^{2+}$ through the $Na^+-Ca^{2+}$ exchange, and the $pH_i$ increase could cause an increase in the $Ca^{2+}$ sensitivity of myofilaments and may augment the ${\alpha}_1$-AR-mediated positive inotropic response.

한국재래산양 귀밑샘에 관한 전자현미경적 연구

김진상,이흥식,이인세,강태천,Kim, Jin-sang,Lee, Heungshik S,Lee, In-se,Kang, Tae-cheon 대한수의학회 1994 大韓獸醫學會誌 Vol.34 No.4

The ultrastructural investigations of the parotid gland of Korean native goat were carried out by transmission electron microscopy. The results were as follows; 1. The acini of parotid gland were composed of light and dark acinar cells. 2. In the light acinar cells, the secretory granules were classified into three types according to their electron densities and dense bodies. One type of granules was low electron density and had no dense bodies. Another type was low electron density and had dense bodies, and the other type was low electron density and had granular dense bodies. 3. The secretory granules of dark acinar cells showed high electron density and were also calssified into three types by dense bodies as the same way as in the light acinar cells. 4. The intercalated ducts consisted of simple cuboidal epithelium. The nuclei of epithelial cells were oval or round form, located at the central part, and had infolding nuclear membranes and one or two nucleoli. 5. The cells of both of the striated and excretory ducts were composed of light cells, dark cells, specific light cells and basal cells. 6. The nerve terminals were distinguished into two types. One had large granular synaptic vesicles, and another had small agranular synaptic vesicles.

기니픽 심근의 전기생리학적 특성에 미치는 α¹-Adrenoceptor 자극효과

김진상,Kim, Jin-sang 대한수의학회 1993 大韓獸醫學會誌 Vol.33 No.2

The effects of ${\alpha}_1$-adrenergic stimulation on membrane potential, intracellular sodium activity $(a_N{^i{_a}})$, and contractility were investigated in the isolated papillary muscle of euthyroid, hyperthyroid, and hypothyroid guinea pigs. Cardiac alterations in the thyroid state have been shown to induce marked changes in action potential characteristics, the most pronounced shortening of action potential duration by hyperthyroidism and an increase in duration by hypothyroidism. $10^{-5}M$ Phenylephrine produced a decrease in $(a_N{^i{_a}})$ in euthyroid and hypothyroid preparations, but an increase in $(a_N{^i{_a}})$ in hyperthyroid ones. The major findings were that phenylephrine produced a stronger positive inotropic effect(PIE) without initial negative inotropic effect(NIE) in hyperthyroid preparations, while phenylephrine produced markedly NIE in hypothyroid ones. The alterations in membrane potential, $(a_N{^i{_a}})$, and contractility were abolished by $3{\times}10^{-5}M$ prazosin in hypothyroidism. In hypothyroid ventricular muscle, the decrease in $(a_N{^i{_a}})$ caused by phenylephrine were not abolished or reduced by $10^{-5}M$ strophanthidin, $10^{-5}M$ TTX, $3{\times}10^{-4}M$ lidocaine, or $100^{-5}M$ verapamil. These results indicate that the ${\alpha}_1$-adrenoceptor-mediated decrease in $(a_N{^i{_a}})$ is not associated with a stimulation of the $Na^+$-$K^+$ pump, inhibition of the $Na^+$ or $Ca^+$ channel in hypothyroid ventricular muscle. $10^{-5}M$ Phenylephrine decreased $(a_N{^i{_a}})$ but increased $(a_N{^i{_a}})$ in the presence of a PKC activator phorbol dibutyrate$(PDB_u)$. In conclusion, it is suggested that the following sequence of events in response to phenyleplhane occur in guinea pig ventricular muscle. First, changes in thyroid state may contribute to the ventacular electrophysiological propeties or ion transport system. Second, the adrenoceptor-mediated initial transient NIE may be associated with the decrease in $(a_N{^i{_a}})$ by PKC activation.

가토(家兎)에서 nitrite에 의한 methemoglobinemia에 미치는 selenium의 영향(影響)

김진상,한정희,김기수,Kim, Jin-sang,Han, Jeong-hee,Kim, Kye-soo 대한수의학회 1991 大韓獸醫學會誌 Vol.31 No.1

The protective of influences of sodium selenitc ($Na_2SeO_3$) against the methemoglobinemia with sodium nitrite were investigated on hemoglobin, methemoglobin, glutathione peroxidase and NADH-methemoglobin reductase activity in rabbits which were given 0,1,3 and 9ppm sodium selenite of drinking water for a week. Dietary selenium did not alter total hemoglobin in the blood of rabbits. Selenium was found to decrease nitrite-induced methemoglobin in a dose-dependent manner. The glutathione peroxidase activity was also increased by selenium in all the experimental groups. However, the NADH-methemoglobin reductase activity by selenite did not show significant differences as concerns the methemoglobinemia. These results showed that selenium could inhibit nitrite-induced methemoglobinemia. Its influence of inhibition is suggested that the effect of the reduction of methemoglobin was greatly stimulated by glutathione peroxidase activity.

한국재래산양의 큰침샘에 대한 형태학적 연구

김진상,이흥식,이인세,이성준,Kim, Jin-sang,Lee, Heungshik S.,Lee, In-se,Yi, Seong-joon 대한수의학회 1992 大韓獸醫學會誌 Vol.32 No.4

The morphological findings of the parotid, mandibualr and sublingual salivary glands of the Korean native goat have been investigated by the histological and histochemical observation using the light microscope. Tissues were fixed with 10% neutral buffered formalin and Bouin's solution, and embedded in paraffin. The tissue sections were stained with hematoxylin and eosin, Heidenhain's azocarmine-aniline blue, alcian blue, toluidine blue, periodic acid Schiff, aldehyde fuchsin, alcian blue-periodic acid Schiff and aldehyde fuchsin-alcian blue. Some sections were stained with the alcian blue after each teatment of diastase digestion, methylation, methylation-saponification, and neuraminidase digestion. The results were as follows ; 1. The major salivary glands were compound. tubuloacinar glands, and the parenchyma was composed of acini, intercalated ducts, striated ducts and excretory ducts. 2. The acini were composed of serous cells in the parotid gland, and mucous cells, serous cells and seous demilunes in the mandibular gland. The acini of the sublingual glands were composed of mucous cells and serous demilunes. 3. In histochemistry, the serous cells of the parotid gland contained neutral mucin and enzyme-liable silaic acid. 4. The serous cells and demilunes of the mandibular gland contained neutral mucin and enzyme-liable sialic acid, and the mueous cells contained sulfated mucin, enzyme liable sialic acid and neutral mucin 5. In the sublingual gland, the mucous cells contained sulfated mucin, enzyme-resistant sialic acid and neutral mucin, and the serous demilunes contained neutral mucin and enzyme-resistant sialic acid.