• Title/Summary/Keyword: Adaptive weight

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A Personalized Music Recommendation System with a Time-weighted Clustering (시간 가중치와 가변형 K-means 기법을 이용한 개인화된 음악 추천 시스템)

  • Kim, Jae-Kwang;Yoon, Tae-Bok;Kim, Dong-Moon;Lee, Jee-Hyong
    • Journal of the Korean Institute of Intelligent Systems
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    • v.19 no.4
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    • pp.504-510
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    • 2009
  • Recently, personalized-adaptive services became the center of interest in the world. However the services about music are not widely diffused out. That is because the analyzing of music information is more difficult than analyzing of text information. In this paper, we propose a music recommendation system which provides personalized services. The system keeps a user's listening list and analyzes it to select pieces of music similar to the user's preference. For analysis, the system extracts properties from the sound wave of music and the time when the user listens to music. Based on the properties, a piece of music is mapped into a point in the property space and the time is converted into the weight of the point. At this time, if we select and analyze the group which is selected by user frequently, we can understand user's taste. However, it is not easy to predict how many groups are formed. To solve this problem, we apply the K-means clustering algorithm to the weighted points. We modified the K-means algorithm so that the number of clusters is dynamically changed. This manner limits a diameter so that we can apply this algorithm effectively when we know the range of data. By this algorithm we can find the center of each group and recommend the similar music with the group. We also consider the time when music is released. When recommending, the system selects pieces of music which is close to and released contemporarily with the user's preference. We perform experiments with one hundred pieces of music. The result shows that our proposed algorithm is effective.

Effect of Naeso-san on Gastric Motility between Normal Intact and Antral Dilatated Rats (내소산(內消散)의 정상 및 위 유문부 확장 흰 쥐의 위 운동성에 대한 효능)

  • Kim, Jin-Seok;Yoon, Sang-Hyub
    • The Journal of Internal Korean Medicine
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    • v.29 no.1
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    • pp.117-129
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    • 2008
  • Background & Objective : Naeso-san(NSS) has been used for the treatment of functional dyspepsia, regarded as a gastric dysmotility disease. A main cause of gastric dysmotility is antral dilatation or antroduodenal uncoordination. Therefore, we investigated the effect of NSS on gastric motility and its mechanism of action, as well as the morphologic changes in antral dilatated rats. Methods : Antral dilatated rats were induced by wrapping a nonabsorbable rubber ring(D:6mm, W:4mm, T:1mm) around the 1st portion of the duodenum for 8 weeks. Then morphologic changes were investigated and compared with normal intact rats before and after 8 weeks. Gastric emptying was measured by administration of normal saline(NS) or NSS in normal intact and antral dilatated rats. In another series of experiments to evaluate the mechanism of NSS under delayed conditions, normal intact rats were treated with atropine sulfate(1mg/kg, s.c.), quinpirole HCl(0.3mg/kg, i.p.), $NAME(N^{G}-nitro-L-arginine$ methyl ester, 75mg/kg, s.c.) and cisplatin(10mg/kg, i.p.), respectively. The myoelectrical activity of the gastric smooth muscle was recorded in normal intact and antral dilatated rats. The contractile waves were measured for 30 minutes before and after administration of each solution(NS, NSS). Results : Body weight gain of antral dilatated rats was significantly lower than that of the controls. Futhermore, we found the thickness of the mucosal and muscular layers and surface area of the stomach increased significantly compared with controls. NSS 278㎎/㎏ improved gastric emptying more than normal saline or NSS 93mg/kg in normal intact(p=0.026) and antral dilatated rats(p=0.03). NSS enhanced gastric emptying significantly in the NAME treated group(p=0.002). NSS 278mg/kg increased the significant postprandial dominant power than that of NS in normal intact rats, whereas there was no statistical significance in antral dilatated rats. Conclusions : NSS stimulates gastric motility through the cholinergic pathway. We expect that pathologic model with antral dilatation can be used as an exprimental tool which is similar to dyspepsia and NSS would be effective especially in dysmotility-like functional dyspepsia with antral dilatation or impaired reservoir functions such as gastric adaptive relaxation.

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Cytochemical Study on the Cytochrome Oxidase Activity and Myocardial Adaptation to Treadmill Exercise in Rat (흰쥐에서 Treadmill 훈련에 따른 심근의 적응과 cytochrome oxidase 활성에 관한 세포화학적 연구)

  • Choi, Jeung-Mok;Lee, Choong-Sik
    • Applied Microscopy
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    • v.31 no.1
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    • pp.59-70
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    • 2001
  • The present study was to elucidate the cytochemical study on the cytochrome oxidase (CO) activity and myocardial adaptation to treadmill exercise in rat. The three month Sprague-Dowley male $(150{\pm}10g)$ were used in experimental animal. The experimental groups were divided into 2 groups: the normal sedentary group and the treadmill exercise group. On each 1st and 3rd day, 1st, 4th, 8th, and 12th experimental week four rats of each group were sacrificed for tests. The morphometrical measurements were used to evalute the change of heart weight, rate of myocardial fibers to capillaries, and cytochemical study of CO activities, using light and electron microscopy. The results were as follows: The heart weights were more increased in the treadmill exercise group than those of their sedentary group. The rate of myocardial fibers to capillaries were not changed in sedentary group, but those were significantly from 4th weeks in the treadmill exercise group. The CO activity was not changed in sedentary group, but increased in treadmill exercise group after 1 st week. I and III types of CO activity were increased In sedentary group, in contast to II and III types in treadmill exercise group on electron micrographic study. These results suggest that, the treadmill exercise-induced changes in CO activity and rate of myocardial fibers to capillaries appear to be related to exercise, and the adaptive response seems to occurs from 4th week of treadmill exercise.

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The Metabolic Effects of FGF21: From Physiology to Pharmacology (생리, 약학적 관점에서 fibroblast growth factor 21 (FGF21)의 대사 효과 고찰)

  • Song, Parkyong
    • Journal of Life Science
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    • v.30 no.7
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    • pp.640-650
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    • 2020
  • Fibroblast growth factor 21 (FGF21) is an atypical member of the FGF protein family which is highly synthesized in the liver, pancreas, and adipose tissue. Depending on the expression tissue, FGF21 uses endo- or paracrine features to regulate several metabolic pathways including glucose metabolism and energy homeostasis. Different physiologically stressful conditions such as starvation, a ketogenic diet, extreme cold, and mitochondrial dysfunction are known to induce FGF21 synthesis in various tissues to exert either adaptive or defensive mechanisms. More specifically, peroxisome proliferator-activated receptor gamma and peroxisome proliferator-activated receptor alpha control FGF21 expression in adipose tissue and liver, respectively. In addition, the pharmacologic administration of FGF21 has been reported to decrease the body weight and improve the insulin sensitivity and lipoprotein profiles of obese mice and type 2 diabetes patients meaning that FGF21 has attracted huge interest as a therapeutic agent for type 2 diabetes, obesity, and non-alcoholic fatty liver disease. However, understanding FGF21 remains complicated due to the paradoxical condition of its tissue-dependent expression. For example, nutrient deprivation largely increases hepatic FGF21 levels whereas adipose tissue-derived FGF21 is increased under feeding condition. This review discusses the issues of interest that have arisen from existing publications, including the tissue-specific function of FGF21 and its action mechanism. We also summarize the current stage of a clinical trial using several FGF21 analogs.

Tree Growth and Fruit Characteristics of 'Nero' Black Chokeberry According to Different Cultivation Regions and Altitudes (재배지역 및 고도에 따른 블랙초크베리 'Nero'의 수체 생육 및 과실 특성)

  • Won, Jungyeon;Shin, Hyunsuk;Oh, Youngjae;Han, Hyeondae;Kwon, Yeuseok;Kim, Daeil
    • Korean Journal of Plant Resources
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    • v.31 no.2
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    • pp.136-148
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    • 2018
  • The study was performed to investigate basic tree growth and fruit characteristics of 'Nero' black chokeberry (Aronia melanocarpa) depending on the different cultivation regions and altitudes in 2014, 2015. Tree growth and change of developmental stages of 'Nero' were similar regardless of meteorological environment of the four cultivation regions (Danyang, Okcheon, Yeongdong, and Geumsan) in 2014. Fruit characteristics of 'Nero' were significant differences in berry weight and anthocyanin content among the four orchards due to difference in cultivation techniques and relatively wide daily temperature range just before harvest, respectively. Tree growth and change of developmental stages of 'Nero' grown at the two orchards with different altitudes appeared to be similar during the successive years 2014 and 2015. Soluble solids content of the berries cultivated at low altitude (117 m) was higher than at high altitude (342 m). Acidity showed an inverse pattern with soluble solids content. Anthocyanin content increased progressively until at the middle of August, 2014-15 and then it decreased. Our results showed that black chokeberry is a species adaptive to the domestic environment as there were no differences in tree growth and change of developmental stages of 'Nero'. Considering fruit quality of black chokeberry such as soluble solids content, acidity, and anthocyanin content, our results suggest that optimal harvest period of black chokeberry 'Nero' is August 8 to 19.

De-interlacing Algorithm based on Motion Compensation Reliability (움직임 보상의 신뢰도에 기반 한 순차주사화 알고리즘)

  • Chang, Joon-Young;Kim, Young-Duk;Kang, Moon-Gi
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.46 no.6
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    • pp.102-111
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    • 2009
  • In this paper, we propose a de-interlacing algorithm that combines a motion compensation (MC) method and the vertical-temporal filter with motion compensation (MC V-T filter) according to motion compensation reliability. The MC method represent one of the best ways of improving the resolution of de-interlaced frames, but it may introduce motion compensation artifacts in regions with incorrect motion information. In these regions, the MC V-T filter that is very robust to motion vector errors can be used to correct motion compensation artifacts. The combination between two methods is controlled by the motion compensation reliability that is measured by analyzing the estimated motion vectors and the results of MC. The motion compensation reliability contains information about motion compensation artifacts of MC results and determines the combination weight according to this information. Therefore, the combination rule of the proposed method is more accurate than those of the conventional methods and it enables the proposed method to provide high quality video sequences without producing any visible artifacts. Experimental results with various test sequences show that the proposed algorithm outperforms conventional algorithms in terms of both visual and numerical criteria.

An Artificial Visual Attention Model based on Opponent Process Theory for Salient Region Segmentation (돌출영역 분할을 위한 대립과정이론 기반의 인공시각집중모델)

  • Jeong, Kiseon;Hong, Changpyo;Park, Dong Sun
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.7
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    • pp.157-168
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    • 2014
  • We propose an novel artificial visual attention model that is capable of automatic detection and segmentation of saliency region on natural images in this paper. The proposed model is based on human visual perceptions in biological vision and contains there are main contributions. Firstly, we propose a novel framework of artificial visual attention model based on the opponent process theory using intensity and color features, and an entropy filter is designed to perceive salient regions considering the amount of information from intensity and color feature channels. The entropy filter is able to detect and segment salient regions in high segmentation accuracy and precision. Lastly, we also propose an adaptive combination method to generate a final saliency map. This method estimates scores about intensity and color conspicuous maps from each perception model and combines the conspicuous maps with weight derived from scores. In evaluation of saliency map by ROC analysis, the AUC of proposed model as 0.9256 approximately improved 15% whereas the AUC of previous state-of-the-art models as 0.7824. And in evaluation of salient region segmentation, the F-beta of proposed model as 0.7325 approximately improved 22% whereas the F-beta of previous state-of-the-art models.

Chronic Alcohol Consumption Results in Greater Damage to the Pancreas Than to the Liver in the Rats

  • Lee, Seong-Su;Hong, Oak-Kee;Ju, Anes;Kim, Myung-Jun;Kim, Bong-Jo;Kim, Sung-Rae;Kim, Won-Ho;Cho, Nam-Han;Kang, Moo-Il;Kang, Sung-Koo;Kim, Dai-Jin;Yoo, Soon-Jib
    • The Korean Journal of Physiology and Pharmacology
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    • v.19 no.4
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    • pp.309-318
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    • 2015
  • Alcohol consumption increases the risk of type 2 diabetes. However, its effects on prediabetes or early diabetes have not been studied. We investigated endoplasmic reticulum (ER) stress in the pancreas and liver resulting from chronic alcohol consumption in the prediabetes and early stages of diabetes. We separated Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a type-2 diabetic animal model, into two groups based on diabetic stage: prediabetes and early diabetes were defined as occurrence between the ages of 11 to 16 weeks and 17 to 22 weeks, respectively. The experimental group received an ethanol-containing liquid diet for 6 weeks. An intraperitoneal glucose tolerance test was conducted after 16 and 22 weeks for the prediabetic and early diabetes groups, respectively. There were no significant differences in body weight between the control and ethanol groups. Fasting and 120-min glucose levels were lower and higher, respectively, in the ethanol group than in the control group. In prediabetes rats, alcohol induced significant expression of ER stress markers in the pancreas; however, alcohol did not affect the liver. In early diabetes rats, alcohol significantly increased most ER stress-marker levels in both the pancreas and liver. These results indicate that chronic alcohol consumption increased the risk of diabetes in prediabetic and early diabetic OLETF rats; the pancreas was more susceptible to damage than was the liver in the early diabetic stages, and the adaptive and proapoptotic pathway of ER stress may play key roles in the development and progression of diabetes affected by chronic alcohol ingestion.

Development of a Climate Change Vulnerability Index on the Health Care Sector (기후변화 건강 취약성 평가지표 개발)

  • Shin, Hosung;Lee, Suehyung
    • Journal of Environmental Policy
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    • v.13 no.1
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    • pp.69-93
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    • 2014
  • The aim of this research was to develop a climate change vulnerability index at the district level (Si, Gun, Gu) with respect to the health care sector in Korea. The climate change vulnerability index was esimated based on the four major causes of climate-related illnesses : vector, flood, heat waves, and air pollution/allergies. The vulnerability assessment framework consists of six layers, all of which are based on the IPCC vulnerability concepts (exposure, sensitivity, and adaptive capacity) and the pathway of direct and indirect impacts of climate change modulators on health. We collected proxy variables based on the conceptual framework of climate change vulnerability. Data were standardized using the min-max normalization method. We applied the analytic hierarchy process (AHP) weight and aggregated the variables using the non-compensatory multi-criteria approach. To verify the index, sensitivity analysis was conducted by using another aggregation method (geometric transformation method, which was applied to the index of multiple deprivation in the UK) and weight, calculated by the Budget Allocation method. The results showed that it would be possible to identify the vulnerable areas by applying the developed climate change vulnerability assessment index. The climate change vulnerability index could then be used as a valuable tool in setting climate change adaptation policies in the health care sector.

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Species-specific Growth Responses of Betula costata, Fraxinus rhynchophylla, and Quercus variabilis Seedlings to Open-field Artificial Warming (거제수나무, 물푸레나무, 굴참나무 묘목의 실외 인위적 온난화에 대한 수종 특이적 생장 반응)

  • Han, Saerom;An, Jiae;Yoon, Tae Kyung;Yun, Soon Jin;Hwang, Jaehong;Cho, Min Seok;Son, Yowhan
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.16 no.3
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    • pp.219-226
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    • 2014
  • Evaluation of tree responses to temperature elevation is critical for a development of forest management techniques coping with climate change. We conducted a study on the growth responses of Betula costata, Fraxinus rhynchophylla, and Quercus variabilis seedlings to open-field artificial warming. Artificial warming set-up using infra-red heater was built in 2012 and the temperature in warmed plots was regulated to be consistently $3^{\circ}C$ higher than that of control plots. The seeds of three species were sown, and the responses of growth, biomass allocation, and net photosynthetic rate of newly-germinated seedlings on the open-field artificial warming were determined. As a result, the growth responses of the seedlings differed with the species. B. costata showed decreases in the height to diameter ratio (H/D ratio), biomass, root weight to shoot weight ratio, and net photosynthetic rate. However, root collar diameter (RCD), height, biomass, and net photosynthetic rate of Q. variabilis were increased, while the response of F. rhynchophylla was rather obscure. There was no significant difference between warmed and control plots in seedling growth for 3 species in July, whereas, RCD, height, and H/D ratio of Q. variabilis were increased and H/D ratio of B. costata was decreased in November under warming. Species-specific growth responses to warming were similar to the species-specific responses of net photosynthetic rate and biomass allocation; therefore, net photosynthetic rate and biomass allocation might attribute to growth responses to warming. Besides, a relatively obvious response in autumn compared to summer might be affected by the phenological change following artificial warming. Species-specific responses of three deciduous species to warming in this study could be applied to the development of adaptive forest management policies to climate change.