• 제목/요약/키워드: preferences for science

검색결과 873건 처리시간 0.031초

심층 강화학습 기반의 대학 전공과목 추천 시스템 (Recommendation System of University Major Subject based on Deep Reinforcement Learning)

  • 임덕선;민연아;임동균
    • 한국인터넷방송통신학회논문지
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    • 제23권4호
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    • pp.9-15
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    • 2023
  • 기존의 단순 통계 기반 추천 시스템은 학생들의 수강 이력 데이터만을 활용하기 때문에 선호하는 수업을 찾는 것에 많은 어려움을 겪고 있다. 이를 해결하기 위해, 본 연구에서는 심층 강화학습 기반의 개인화된 전공과목 추천 시스템을 제안한다. 이 시스템은 학생의 학과, 학년, 수강 이력 등의 정형 데이터를 기반으로 학생들 간의 유사도를 측정하며, 이를 통해 각 전공과목에 대한 정보와 학생들의 강의 평가를 종합적으로 고려하여 가장 적합한 전공과목을 추천한다. 본 논문에서는 이 DRL 기반의 추천 시스템을 통해 대학생들이 전공과목을 선택하는 데에 유용한 정보를 제공하며, 이를 통계 기반 추천 시스템과 비교하였을 때 더 우수한 성능을 보여주는 것을 확인하였다. 시뮬레이션 결과, 심층 강화학습 기반의 추천 시스템은 통계 기반 추천 시스템에 비해 수강 과목 예측률에서 약 20%의 성능 향상을 보였다. 이러한 결과를 바탕으로, 학생들의 강의 평가를 반영하여 개인화된 과목 추천을 제공하는 새로운 시스템을 제안한다. 이 시스템은 학생들이 자신의 선호와 목표에 맞는 전공과목을 찾는 데에 큰 도움이 될 것으로 기대한다.

Nutritive Value of Grasses in Semi-arid Rangelands of Ethiopia: Local Experience Based Herbage Preference Evaluation versus Laboratory Analysis

  • Keba, Habtamu T.;Madakadze, I.C.;Angassa, A.;Hassen, A.
    • Asian-Australasian Journal of Animal Sciences
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    • 제26권3호
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    • pp.366-377
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    • 2013
  • We examined the nutritive value of common grass species in the semi-arid rangelands of Borana in southern Ethiopia using local experience based herbage preference (LEBHP) perception and laboratory techniques. Local pastoralists in the study area were asked to identify common grass species and rank them according to the species' preferences and palatability to cattle. The pastoralists listed a total of 15 common grass species which were then sampled during the main rain and cold dry seasons and analyzed for crude protein (CP), Neutral Detergent Fiber (NDF), Acid Detergent Fiber (ADF) and ash content to verify pastoralists' claim regarding the quality of individual species. The relative feed value (RFV) and dry matter digestibility (DMD) were also calculated using NDF and ADF contents. Spearman's rank correlation was used to examine possible relationships between laboratory results and pastoralists' experience on grass quality. Cenchrus ciliaris, Chrysopogon aucheri, Digitaria milanjiana, Eragrostis papposa and Panicum maximum were the top five species based on LEBHP perception. There were indications of inconsistency in terms of LEBHP perception among the different pastoral communities. The chemical composition of all grass species showed significant (p<0.05) variation between sites, seasons and species. The results showed that the CP values for the Borana rangelands were in the range of 8.7% in the main rain season to 5.1% for the cold dry season. The fiber constituents were relatively low in the main rain season compared to the cold dry season. Overall, Digitaria milanjiana had the highest CP (16.5%) content, while the least was recorded with Heteropogon contortus (10.8) and Aristida adoensis (9.8%) during the main rain season. It seems that the spatial variability of landscapes within the wider geographical regions, soil properties and texture, and land-use patterns probably contributed to site differences in species quality. Generally, the RFV of individual grass species was significantly (p<0.05) varied between and within sites. The ranking of species by pastoralists according to their preferences by cattle was highly correlated with the chemical composition of laboratory results of individual grass species with 'r' values for CP (0.94), ash (0.95), NDF (-0.98), ADF (-0.93) and ADL (-0.93). We suggest the complimentary use of LEBHP and laboratory techniques in evaluating the nutritive quality of rangeland forage species for sustainable animal production.

구이용 전기팬과 과열증기로 열처리한 고등어구이의 이화학적인 품질특성 및 기호도 비교평가 (Comparison on Physico-Chemical and Affective Properties in Mackerel Cooked by Electric Pan and under Superheated Steam)

  • 유광연;조인희
    • 한국식품조리과학회지
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    • 제32권2호
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    • pp.204-210
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    • 2016
  • Purpose: This study analyzed and compared the physico-chemical and affective properties between mackerels cooked by an electric pan and under superheated steam. Methods: Mackerel were cooked by an electric pan ($95^{\circ}C$) for 10 min and mackerel cooked under superheated steam ($250^{\circ}C$) for 5 min to be internal temperatures of $75{\pm}5^{\circ}C$ and tests to measure proximate composition, color values, texture profiles, microorganism counts and sensory acceptance were performed. Results: The moisture contents were 60.30% and 73.81% in mackerels cooked by electric pan and under superheated steam, respectively. The rate of weight loss in mackerel cooked by electric pan was 39%, whereas it was 29% in mackerel cooked under superheated steam. Mackerel cooked under superheated steam exhibited more yellowness, higher springiness, cohesiveness, gumminess, chewiness, and resilience with more acceptable preferences (appearance, odor, taste, and texture) compared to the mackerel cooked by electric pan. Conclusion: The application of superheated steam technology to fish products could reduce the cooking time and nutritional loss. Also, it could produce highly preferred fish products compared to that prepared by conventional electric pan.

고조리서에서 살펴본 조선시대($15{\sim}19C$) 국의 조리과학적 고찰 I -맑은 국을 중심으로- (A Study on the Cooking Science of Guk(Korean Soup) from Old Cookbooks from the Chosun Dynasty($15{\sim}19C$) -Focused on Malgunguk -)

  • 김귀영;이춘자
    • 동아시아식생활학회지
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    • 제18권5호
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    • pp.711-724
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    • 2008
  • Guk has been a very important part of the Korean table service for a long time. To study the historical transition of traditional Guk, an analysis of old cookbooks from the Chosun dynasty ($15{\sim}19C$) was conducted based on cooking science. The following is the results of 52 types of Malgunguk from representative old cookbooks such as Sangayorok (1450), Suunjabbang (early 1500s), Eumshikdimibang (1670), Jeungbosallimgyungje (1766), Gyuhabchongsu (1815), Juchan (mid 1800s), Sieuijunsu(late 1800s). The ingredients for Malgunguk contain 30, 35, and 12 types of animal foods, plant foods, and seasonings, respectively. Fish and two to three meats are combined for the main ingredients of Guk, to harmonize the taste. Notably, deer and birds such as pheasants along with parts of beef (short ribs, marrow, Holdaegi) were used. Moreover, it is interesting to note that meat such as pork and chicken were favored to beef, which is contrary to preferences of today. There are only a few Malgunguks that have been passed down before the 16th century those after the 17th century have mostly been reported, but the ingredients have been simplified.

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갯벌생태관광에 대한 소비자의 잠재가치 측정에 관한 연구 (Analyzing Consumer's Preference for the Potential Value of Coastal Wetland Ecotourism Using Contingent Choice Method)

  • 장정인;이주석;신철오
    • Ocean and Polar Research
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    • 제33권2호
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    • pp.149-157
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    • 2011
  • As tourist are becoming increasingly environmentally conscious, government and related companies need to establish policies or strategies that encourage ecotourism. The aim of this study is to analyze individual preferences and estimate shadow prices, namely, willingness to pay for coastal wetland ecotourism. This study applies a contingent choice method to measuring marginal WTP for each attribute (tour duration, number of visitors, guide, program) of coastal wetland ecotourism. The finding herein contribute to complementing the valuation methods by estimating various attributes of coastal wetland ecotourism and providing policy-makers with useful methodological framework and quantitative information in the decision-making process related to ecotourism.

경북지역(慶北地域) 관광농업(觀光農業) 육성방안(育成方案) (A Study on farm tourism - in Kyungpook area -)

  • 최규섭;김규래;최상태
    • Current Research on Agriculture and Life Sciences
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    • 제10권
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    • pp.67-97
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    • 1992
  • The study attempted to document the concept of farm tourism by categories and to evaluate the farm tourism projects developed in Kyungpook area, and also to formulate a device for improving such projects in Kyungpook area. For these purposes we have examined the existing patterns of farm tourism projects developed in Kyungpook area since 1986 and evaluated such projects conducted in same area. We also attempted to find out what were the problems conducting such projects. To estimate the demand patterns of farm tourism we have done a survey conducted in city and urban areas and documented consumer's preferences which patterns were willing to. Finally we suggested, in this study, several strategies for improving the farm toruism projects in Kyungpook area.

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Analysis of Agrifood Purchasing Pattern Using Association Rule Mining - Case of the Seoul·Gyeonggido·Incheon in South Korea -

  • Jo, Hyebin;Choe, Young Chan
    • Agribusiness and Information Management
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    • 제4권2호
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    • pp.14-21
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    • 2012
  • Since the Free Trade Agreements (FTAs) with Chile, the EU, and the U.S., Korean agricultural produce markets have turned into a fierce competition landscape. Under these competitive circumstances, marketing is critical. The objective of the research presented herein is to understand the characteristics of customer preferences after locating trends of purchased items. So This research establishes sustainable strategies for Korean agricultural produce. This investigation used market-basket analysis techniques and panel data for its research. Market-basket analysis is a technique which attempts to find groups of items that are commonly found together. The results show that, for one year, processed food using wheat, processed marine products, and pork are commonly bought together and that yogurt and milk also are bought together. The characteristics of customers buying these items are 44 years old and live in a four-person household with two children. These customers do not live with their parents.

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OPTIMIZATION OF THE TEST INTERVALS OF A NUCLEAR SAFETY SYSTEM BY GENETIC ALGORITHMS, SOLUTION CLUSTERING AND FUZZY PREFERENCE ASSIGNMENT

  • Zio, E.;Bazzo, R.
    • Nuclear Engineering and Technology
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    • 제42권4호
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    • pp.414-425
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    • 2010
  • In this paper, a procedure is developed for identifying a number of representative solutions manageable for decision-making in a multiobjective optimization problem concerning the test intervals of the components of a safety system of a nuclear power plant. Pareto Front solutions are identified by a genetic algorithm and then clustered by subtractive clustering into "families". On the basis of the decision maker's preferences, each family is then synthetically represented by a "head of the family" solution. This is done by introducing a scoring system that ranks the solutions with respect to the different objectives: a fuzzy preference assignment is employed to this purpose. Level Diagrams are then used to represent, analyze and interpret the Pareto Fronts reduced to the head-of-the-family solutions.

초.중.고 학교급식에 따른 영양사의 가공식품 이용실태와 인지도 조사 (A Study on Purchase Patterns and Recognition of Processed Foods in Elementary. Middle and High School Meal Service Dietitians)

  • 노정옥;정유경;정수진;차연수
    • 한국가정과학회지
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    • 제10권2호
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    • pp.63-75
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    • 2007
  • The results of this study on Purchase Patterns and Recognition of Processed Foods of School Meal Service Dietitians of elementary, junior and senior high schools in Chonbuk and Deagu Area are as follows : First, the rate of single cooking of the schools surveyed is 100% in Deagu and 66.9% in Chonbuk, and Chonbuk has more small-meal service schools which caused a higher labor cost than Deagu, Secondly, schools in Deagu has purchased not completely processed vegetables and fish and shells than Chonbuk, and Chonbuk(66.9%) has served more Kim-chi products than Deagu(41.6%). Thirdly, nutritional effects and preference have been considered as school dietitians make plans for the menu. Fourthly, the opinions of the school dietitians about processed food are in the order of high sodium content, convenience and the use of preservative, and Chonbuk has responded positively to the articles of future oriented quality, cooking usage and variety while Deagu has thought of it as an economical. The expected effects from the use of processed foods are in the order of saving labor time and student preferences. Fifthly, meat products have been frequently used and more frozen meat products have been used in Deagu and senior high school than Chonbuk and elementary and junior high schools, last, preferences on processed food are in the order of frozen sea food, noodles. dried sea food, processed vegetable and fruit, dairy goods and others. Senior high school dietitians have preferred packed meat products and other frozen processed food more than elementary and junior high school dietitians. The rate of serving processed food had a different depending on the number of students. In this study, dietitians recognize the harmful effects of processed foods over the merits, which means that the rate of using processed food is low. The proper usage of processed foods is thought to improve the preference of students, to have cooking time shortened and to help manage the meal service sanitarily and efficiently. Therefore, companies producing processed foods should do their best to develop safety and health oriented foods to gain the credibility, and the government should make new regulations for people to purchase and obtain processed foods without any doubt.

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경쟁산품선적영향(竞争产品线的影响): 관주전두품패(关注战斗品牌) (The Effects of Product Line Rivalry: Focusing on the Issue of Fighting Brands)

  • Koh, Dong-Hee
    • 마케팅과학연구
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    • 제19권4호
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    • pp.24-31
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    • 2009
  • 公司生产不同功能, 设计, 颜色的产品. 产品扩散的出现有三个不同的原因. 当存在规模经济, 当这种产品和别的产品一起生产时, 单位成本比单独生产要低. 二, 消费者是异构的, 即它们具有不同的品味, 喜好, 或价格弹性. 一家公司可赚取细分为具有类似特点的不同群体的消费者更多的利润. 例如, 产品扩散通过更准确地满足不同消费者的需要来帮助公司增加利润. 产品扩散的第三个原因是基于战略. 生产一定数量的产品, 不仅可以阻止通过提供给一些少数市场的产品进入, 也使得公司可以有效地应付低价格进入. 通过生产各种产品, 公司可以减少利基, 使潜在进入者有较少进入的诱因. 此外, 企业可以生产新产品来应对进入, 我们称之为战斗品牌. 也就是说, 当一个进入者试图以低廉的价格吸引消费者, 已存在者介绍新的低质量的产品, 同时保持现有产品的价格. 产品扩散的缺点是同型装配. 一些买了高价位的产品的消费者会转向低价位的产品. 此外, 当新产品与对手现有的产品的异化程度不高时, 由于激烈的竞争, 产品扩散会降低利润. 许多研究已经在经济分析和市场营销等领域的产品线竞争的影响. 它们展示了一个垄断者可以通过调整质量来解决市场中的消费者对质量的偏好不同的同型装配的问题. 他们发现, 喜欢高品质的产品的消费者将获得他或她最喜欢的质量, 但没有这方面的偏好的消费者将获得比他或她所喜爱的质量低的产品. 本研究分析了产品的竞争在一个双头垄断市场, 两种不同类型的消费者对质量偏好的影响. 我假设这两家公司将在这个意义上的不对称, 一个运营商可以同时生产高, 低质量的产品, 而一个进入者只能产生低质量的产品. 产品扩散的影响是可以通过比较市场结果来解释, 当已存在的运营商生产两种产品和只生产一种产品时. 在这个案例中, 当已存在的运营商只生产高品质的产品, 由于激烈的竞争, 在喜欢低质量产品的消费群中低质量的产品价格趋于下降. 但由于缺乏竞争, 在喜欢高质量产品的消费群中价格会上涨. 据了解, 当企业在进行价格竞争时, 理想状况是当公司的对 手提高价格时, 此公司也提高价格, 这被称为战略补充. 由于价格是战略性的补充, 我们有两种相反的效果. 事实证明, 一个高品质的产品价格上升, 因为竞争力减弱的积极作用超过了战略互补的负面影响. 这意味着, 已存在的运营商推出了低质量的产品时还需要增加高品质产品的价格. 然而, 在进入者的低质量产品的价格变化是模糊的. 二, 此案例中, 已存在的运营商只生产低品质的产品, 在偏好低质量的消费群中价格往往增加. 但在偏好高质量的消费群中价格往往下降. 低质量产品的价格下降是因为负面影响大于正面影响. 而且, 当已存在的运营商生产两种产品时, 其低质量产品的价格往往较高, 尽管两家的低品质的产品质量一样. 此原因由于对高品质产品价格的负面影响, 运营商没有较大的动机去降低低品质产品的价格. 事实上, 竞争的产品线对利润的影响不仅取决于价格变化, 还取决于销售和同型装配. 如果在边际成本同产品质量的差异相比是适中的话, 产品扩散的积极影响大于负面影响, 从而增加利润. 此外, 如果成本差异是非常大(小), 运营商最好只生产一种低 (高)质量的产品. 而且, 本研究还分析了当公司通过关注战斗品牌来决定产品特征时, 竞争产品线的影响. 最近, 大韩航空和韩亚航空公司建立了廉价航空线路, 分别是Jin线路和釜山线. 来应对Hansung航空和济州航空. 另外, 很多网上书店也进入市场, 例如处于领先地位的实体书店Kyobo已经有了自己的网上书店. 通过战斗品牌, 在它的低品质产品跟新成员比起来有差别时, 一个具有高品质产品的运营商通过生产更多的低质量产品可以增加利润.

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