• Journal of the Korean Data and Information Science Society
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• v.24 no.4
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• pp.803-813
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• 2013

The purchase of items in e-commerce is a little bit different from that of items in off-line. The recommendation of items in off-line is conducted by salespersons' recommendation, However, the item recommendation in e-commerce cannot be recommended by salespersons, and so different types of methods can be recommended in e-commerce. Recommender system is a method which recommends items in e-commerce. Preferences of customers who want to purchase new items can be predicted by the preferences of customers purchasing existing items. In the recommender system, the items with estimated high preferences can be recommended to customers. The algorithm of collaborative filtering is used in recommender system of e-commerce, and the list of recommended items is made by estimated values, and then the list is recommended to customers. The dataset used in this research are 100k dataset and 1 million dataset in Movielens dataset. Similar results in two dataset are deducted for generalization. To suggest a new algorithm, distribution features of estimated values are analyzed by the existing algorithm and transformed algorithm. In addition, respondent'distribution features are analyzed respectively. To improve the collaborative filtering algorithm in neighborhood recommender system, a new algorithm method is suggested on the basis of existing algorithm and transformed algorithm.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.4
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• pp.387-396
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• 2004

A scheme to evaluate the number of users and cell coverage of a WCDMA supporting multi-rate traffic is newly presented through calculation of the realizable Erlang capacity from a derived blocking probability and the path loss from the COST231 Walfisch-Ikegami(W) model. We evaluate the voice-data Erlang capacities at various data rates of 15 kbps to 960 kbps and it is shown that they have a linear relationship to each other. When the E$\_$b//N$\_$o/ is low from 4 ㏈ to 3 ㏈ in case of voice capacity of 50 Erlang at 8 kbps, the result shows the increase for the data capacity of 10 Erlang and the enlargement of 100 m for the cell coverage at low rate of 15 kbps, and the increase of 0.11 Erlang and the enlargement of 40 m at high rate of 960 kbps. The increase of the blocking probability results in the increase of the Erlang capacity, but not an effect on the cell coverage, and the increase of active users in a cell results in the decrease of the coverage.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.9
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• pp.4437-4446
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• 2013

The purpose of this study was to development and evaluate the effects of cardiocerebrovascular disease prevention program for taxi drivers on physiological variables(blood pressure, blood sugar, serum lipids) and physical variables(body fat, muscle endurance, cardiopulmonary endurance, balance). This study consisted of two phases: developing the program and evaluating its effectiveness. 1 phase, 321 taxi drivers investigated a health condition and a life habit and an educational need and developed a program with the ground which will reach. 2 phases, The effectiveness of the program was tested in October 2011, with 51 taxi driver. The experimental group was given 12 weeks period exercise 1 weeks 3 time, disease education 4 time, 2 nutrition consultations. Although there was no significant reduction in blood pressure, heart rate, blood sugar, serum lipids, there were statistically significant increases in muscle endurance (t=-7.62 p<.001), cardiopulmonary endurance (t=-3.39, p<.001), balance(t=-4.13, p<.001) and decreased body fat (t= -3.11, p<.015) in before compared to after. These findings suggest that an integrated cardiocerebro-vascular disease prevention program improves physical fitness.

• Journal of Distribution Science
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• v.13 no.1
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• pp.71-81
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• 2015

Purpose - This study aims to examine the effect of audience attitude toward product placement, or PPL, on product attitude and purchase intention. PPL has increasingly been prevailing in TV dramas since the revision of the Broadcasting Act in January 2010, and it is quite widespread in today's society. Therefore, this study intends to investigate how the audience would take a particular attitude toward PPL in TV dramas and how their attitude would affect their product attitude and purchase intention. Research design, data, and methodology - The sample for the current study was drawn from college students in Seoul in December 2013, as the main targets of the products and brands that were advertised by PPL are young people. The questionnaire for this study comprised nine parts, such as the knowledge of PPL, experience of PPL, TV drama watching time, impulsive buying propensity, celebrity imitating buying propensity, attitude toward PPL, attitude toward product, purchase intention, and demographic characteristics. The questionnaire items were measured by 5-point Likert scales. Whether the demographic characteristics and propensity to consume would affect PPL attitude was analyzed and how the PPL attitude would affect purchase intention through product attitude was analyzed as well. To analyze the relationship between variables, structural equation modeling analysis was performed with Amos 18.0. Results - The major findings of the study were as follows. First, whether the demographic characteristics and propensity to consume would affect PPL attitude was analyzed, and it is found that out of the demographic characteristics, only gender and knowledge of PPL exerted an influence on PPL attitude. In addition, celebrity-imitating buying propensity had an impact on PPL attitude. Second, whether PPL attitude would affect purchase intention through product attitude was analyzed by structural equation modeling. Consequently, it is found that PPL attitude impacted purchase intention through product attitude. Conclusions - The findings of the study had the following implications. First, in theoretical aspects, previous studies have proven only that attitude toward PPL influenced attitude toward product and purchase intention separately; however, the current study has investigated the mediated role of attitudes toward PPL. Second, regarding the practical aspects, as PPL attitude exercised an effect on purchase intention as well as product attitude, PPL should be utilized in a manner to stimulate the audience to take a positive attitude to it. Finally, gender, PPL knowledge, and celebrity-imitating buying orientation were identified as influential factors for PPL attitude. Specifically, female consumers showed a lower attitude toward PPL than males, and the consumers who have no knowledge showed a lower attitude toward PPL. The consumers who have celebrity imitating buying propensity expressed a higher attitude toward PPL. These factors should consequently be taken into account when PPL is planned and conducted. The current study has limitations such as the sample object, non- experimental method, and media biases. Therefore, future research should be conducted to address these limitations.

• Journal of Korea Entertainment Industry Association
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• v.14 no.7
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• pp.373-387
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• 2020

This study examined the concept and essence of archetype theories of Johann Wolfgang von Goethe, Rudolf Steiner and Carl Gustav Jung, which theatrically influenced Michael Chekhov. It analyzed how archetype theories were applied in Chekhov's Psychological Gesture and tried to fundamentally understand Chekhov's Psychological Gesture that embraced archetype theories. The concept of archetype repeatedly appears in Chekhov's Psychological Gesture. Chekhov stated that archetype exists in the inner psychology or instinct of the actors and he defined the Psychological Gesture as an archetypal gesture. While exploring references regarding archetype in Chekhov's Psychological Gesture, this study found that it is closely related to archetype theories. Therefore this study thoroughly analyzed Goethe's archetype theory(archetypal plant), Steiner's archetype theory(4 temperament archetypes, 7 human's soul archetypes), Jung's archetype theory(collective unconscious and 4 archetypes, 12 personality archetypes) and it confirmed that archetype theories had a significant influence on Chekhov's Archetype Theory and Psychological Gesture. Goethe and Steiner's archetype theories, Eurythmy are applied to theater education and actor's acting. Likewise, Jung's archetype theory is also adopted theatrical studies and theatrical psychotherapy. The author believes that Chekhov's Archetype Theory and Psychological Gesture influenced by archetype theories will significantly help an actor analyze characters in the play and portray them in creative acting.

• International journal of advanced smart convergence
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• v.12 no.3
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• pp.89-103
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• 2023

Obstructive sleep apnea (OSA) is one of the most prevalent sleep disorders that can lead to serious consequences, including hypertension and/or cardiovascular diseases, if not treated promptly. Continuous positive airway pressure (CPAP) is widely recognized as the most effective treatment for OSA, which needs the proper titration of airway pressure to achieve the most effective treatment results. However, the process of CPAP titration can be time-consuming and cumbersome. There is a growing importance in predicting personalized CPAP pressure before CPAP treatment. The primary objective of this study was to optimize the CPAP titration process for obstructive sleep apnea patients through EEG feature engineering with machine learning techniques. We aimed to identify and utilize the most critical EEG features to forecast key OSA predictive indicators, ultimately facilitating more precise and personalized CPAP treatment strategies. Here, we analyzed 126 OSA patients' PSG datasets before and after the CPAP treatment. We extracted 29 EEG features to predict the features that have high importance on the OSA prediction index which are AHI and SpO2 by applying the Shapley Additive exPlanation (SHAP) method. Through extracted EEG features, we confirmed the six EEG features that had high importance in predicting AHI and SpO2 using XGBoost, Support Vector Machine regression, and Random Forest Regression. By utilizing the predictive capabilities of EEG-derived features for AHI and SpO2, we can better understand and evaluate the condition of patients undergoing CPAP treatment. The ability to predict these key indicators accurately provides more immediate insight into the patient's sleep quality and potential disturbances. This not only ensures the efficiency of the diagnostic process but also provides more tailored and effective treatment approach. Consequently, the integration of EEG analysis into the sleep study protocol has the potential to revolutionize sleep diagnostics, offering a time-saving, and ultimately more effective evaluation for patients with sleep-related disorders.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.1
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• pp.14-21
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• 1997

This experiment was conducted to identify the growth and yield differences in rice cultural types: Broadcasting on flooded paddy surface(BF), drilling on flooded paddy surface(DF), puddled-soil drill seeding(PD), drill seeding on dried paddy flat(DD), and machine transplanting of lO-day old seedling(MT) at National Honam Agricultural Experiment Station in 1995. Among the cultural types of direct seeding, the number of seedling stand showed high in order of DD>BF>DF>PD. Tillering at early growth stage was faster in MT and effective tiller showed higher in MT than in direct seeding. Growth duration from seeding to heading was longer in direct seeding than in MT for 2-13 days of Dongjinbyeo and 10-18 days of Nonganbyeo. Root distribution ratio at the surface soil revealed high in order of BF>DF>PD>DD and MT. Culm wall thickness of 4th internode was thicker in machine transplanting of 10-day old seedling than in direct seeding, and the depth of buried culm showed deep by turns of MT> DD>PD>DF and BF. The height of center gravity and moment related to lodging revealed higher in direct seeding than machine transplanting that resulted high lodging index by turns of BF>DF>DD> PD among the direct seeding cultural type. Lodging was occured seriously in the order of BF>DF>PD>DD =MT in Dongjinbyeo but wasn't significantly different in Nonganbyeo among the cultural type. The yield components and grain yield showed varietal differences but was not significantly different between in MT and in direct seeding, and among cultural types of direct seeding.

• Journal of Practical Agriculture & Fisheries Research
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• v.20 no.1
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• pp.5-18
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• 2018

The field trial was performed to evaluate the rice growth and yield in direct seeding cultivation with iron-coated rice seeds. The required time for seed emergence was for 9~11days in the tested direct seeding methods. That was 1~2days earlier in direct seeding with pregerminated seeds than that of direct seeding with iron-coated seeds. The seedling establishment was highest in water seeding with iron-coated seeds but there was not significant difference in terms of statistical analysis. The rice plant height was taller in water seeding with broadcasting method than that of wet hill-seeding methods and in direct seeding with iron-coated seeds than that of direct seeding with pregerminated seeds. The tiller number in the rice plant was the highest in machine transplanting at 30days after direct seeding(June 17) and in water seeding with iron-coated seeds at 45days after seeding(DAS) and 60DAS. The tiller number of 75 and 90DAS in the tested rice cultivation methods being with 352~405/m² was not significantly different in terms of statistical analysis. The heading time was not different in rice direct seeding methods but 2 day earlier in direct seeding with iron-coated seeds than that of direct seeding with pregerminated seeds. The culm length was the highest in water seeding with iron-coated seeds and the panicle length was the longest in wet hill-seeding with pregerminated seeds. The panicle number per m² was highest in water seeding with iron-coated seeds but not significant difference among the tested rice cultivation methods. The water seeding with iron-coated seeds resulted in the highest spikelet number per m² and the heaviest grain weight of brown rice. Percentage of ripened kernel was the highest in wet hill-seeding with iron-coated seeds. But there were not significant among the tested rice cultivation methods. The milled rice yield in direct seeding methods was 3~21% higher than that in machine transplanting. Water seeding with iron-coated seeds recorded the highest milled rice yield being with 6.86t/ha.The occurrence of sheath blight was high according to machine transplanting>wet hill-seeding>water seeding. Weed occurrence was the highest in water seeding with pregerminated seeds. Weedy rice occurred not in machine transplanting but occured 0.6~0.7% in direct seeding methods with pregerminated seeds and 0.1% in direct seeding with iron-coated seeds.

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.2
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• pp.84-90
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• 2018

Cultivation of high-quality forage crop by using fallow field during winter is required for national high feed self-sufficiency and establishment of self-supply system of high-quality forage crop. Field experiments for cultivation of high-quality winter forage crop were conducted at the paddy and upland fields in Cheonan and Anseong city with treatments of single Italian ryegrass(IRG) and IRG mixed with forage barley at the paddy field and of single forage barley and forage barley mixed with IRG at the upland field in the Mid-west plain. Several cultivation conditions such as broadcasting IRG seed under standing rice, sowing time, tillage method, drainage condition, mixed sowing with forage barley were compared to know the change of growth, yield and quality of winter forage crop. In particular, over-wintering rate and dry matter yield were decreased significantly in late-sown IRG and moisture-stressed forage barley. Yield and quality of forage crops were increased by sowing after tillage, mixed sowing of IRG with barley at the paddy field with good drainage. High yield as much as dry matter $10MT\;ha^{-1}$ with high feed value could be obtained by early sowing of feed barley mixed with IRG at the upland field. Cultivation conditions such as early sowing, sowing after tillage, drainage management are required for higher dry matter yield, quality and stable cultivation of winter forage crops in the mid-west plain of Korea.

• Korean journal of communication and information
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• v.16
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• pp.71-107
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• 2001

미국에서 이루어진 인터넷 중독 현상에 대한 초기 연구는 인터넷 중독을 알코올중독과 같은 개인의 정신적 질병으로 간주하는 의사들에 의해 주도되었다. 그러나 사회현상으로서 인터넷 중독에 대한 사회과학자들의 관심이 증대되면서 인터넷 중독의 원인을 밝히는 본격적인 연구가 이루어진다. 인터넷 이용과 초고속 인터넷 망 보급속도에서 세계최고 수준을 자랑하는 우리의 경우에도 인터넷 이용에 따른 많은 부정적인 현상들이 나타남으로써 사회적인 문제로 대두되고 있다. 이에 따라 인터넷 중독에 대한 일부 연구가 수행되었는데 이들 연구들은 인터넷 이용패턴과 이용동기를 개별적으로 분석하고 인터넷 중독정도를 측정하는 차원에 머물고 있다. 즉, 인터넷 중독의 원인을 분석하는 차원에 이르지 못하고 있다. 또한 대부분의 연구들이 10대 청소년을 연구대상으로 하고 있기 때문에 다른 연령층의 인터넷 이용특성을 파악하는 데 한계를 가지고 있다. 이 같은 현실 인식을 바탕으로 본 연구는 2000년에 발표된 한국전산원 통계수치에서 인터넷을 가장 많이 이용하는 집단으로 조사된 대학생들을 연구대상으로, (1) 이들의 인터넷 이용패턴과 이용동기를 밝히고 (2) 이들 변인들과 인터넷 중독과의 상호관련성을 분석하며 (3) 인터넷 중독의 정도와 중독요인을 조사하고 (4) 마지막으로 인터넷 이용이 다른 미디어 이용과 면대면 커뮤니케이션에 미치는 영향을 분석하고 있다. 본 연구의 자료는 2000년 5월 8일부터 19일까지 2주간에 걸쳐 서울시내 대학생들을 대상으로 강의시간에 설문지를 배포하고 응답자가 설문지에 답하는 방법을 통해 수집되었다. 수집된 556명의 설문지 가운데 유효한 512명의 설문지가 통계적인 방법을 통해 분석되었다. 설문지는 (1) 인터넷 이용패턴 (2) 인터넷 이용 동기 (3) 인터넷 의존도 (4) 인터넷 이용 이후 다른 미디어 이용정도 (5) 인터넷 이용 이후 면대면 커뮤니케이션 정도 (6) 인구통계학적 변인을 측정하는 질문 내용으로 구성되었다. 통계 분석 후 나타난 몇 가지 주요결과를 요약하면 아래와 같다. (1) 이용동기와 인터넷 이용과의 상호관련성 이용동기를 요인 분석한 결과, 6개의 이용동기가 나타났는데 오락이 가장 주요한 동기였으며 다음으로 교육/정보, 현실도피, 외로움, 쇼핑, 그리고 성적 만족 순으로 나타났다. 이용 동기들을 인터넷 이용시간과의 상호관련성을 통계 분석한 결과 기존 연구결과와 달리 성적 만족이 6가지 요인 가운데 가장 낮은 상호관련성을 보였다. 또한 이용동기 분석에서 두 번째 높게 나타난 교육/정보 역시 성적 만족 다음으로 낮은 상호관련성을 보여주었다. 이는 대학생들의 인터넷 이용이 10대들의 인터넷 이용형태와 상당히 다르다는 것을 보여주는 것으로 본 연구에서는 수행하지 못한 이 같은 결과가 나오게 된 이유를 밝히는 후속연구가 필요할 것으로 보인다. (2) 인터넷 이용동기와 인터넷 서비스와의 상호관련성 '오락은 게임, 토론그룹, 전자메일, 채팅과 상호관련을 가진 것으로 나타났으며, 교육/정보는 검색과 쇼핑, 현실도피는 게임과 토론그룹, 외로움은 토론그룹, 전자메일과 채팅, 쇼핑은 온라인 쇼핑과 상호관련성이 있는 것으로 분석되었다. 흥미로운 사실은 성적 만족과 관련해서 게임과 채팅은 긍정적인 상호관련을 가진 것으로 나타난 반면 전자메일 서비스 이용은 성적 만족과 부정적인 상호관련을 가진 것으로 분석되었다. 이는 대학생들이 지루하게 느끼거나 외로움을 느낄 때 전자메일을 주로 이용하지만 성적 만족을 위해 전자메일을 이용하지 않고 있다는 사실을 보여주는 것이다. (3) 인터넷 이용 이후 다른 미디어와 면대면 커뮤니케이션과의 관계 인터넷을 이용한 후 응답자들의 전통적인 미디어(텔레비전, 라디오, 신문, 잡지, 편지, 전화) 이용이 감소되었으며 친구, 가족, 이성친구와의 면대면 커뮤니케이션 역시 감소된 것으로 나타났는데 이 같은 감소가 인터넷 이용과 관련이 있는 것으로 나타났다. (4) 인터넷 중독 정도와 중독 요인 10대들을 대상으로 한 기존 연구에서 나타난 인터넷 중독 현상이 대학생 집단에서는 나타나지 않았다. 그러나 응답자의 28.5%가 중독집단으로 발전될 가능성을 가진 잠재적인 인터넷 의존자(Moderate Internet Dependent)로 조사되었다. 인터넷 중독을 설명하는 요인으로 이용동기 가운데 오락, 외로움과 현실도피가 주요 변인으로 나타났으며 인터넷 이용시간 역시 주요변인으로 분석되었다. 흥미 있는 결과는 선행연구에서 인터넷 중독과 밀접한 관련 있는 인터넷 서비스로 조사된 게임과 채팅이 주요변인으로 나타나지 않았다는 것이다. 또한 인터넷 이용동기와 이용시간과의 상호관련 조사 결과에서처럼 전자메일서비스는 인터넷 중독과 부정적인 관계가 있는 것으로 조사되었다.