• 제목/요약/키워드: school selection

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초분광 표적 탐지를 위한 L2,1-norm Regression 기반 밴드 선택 기법 (Band Selection Using L2,1-norm Regression for Hyperspectral Target Detection)

  • 김주창;양유경;김준형;김준모
    • 대한원격탐사학회지
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    • 제33권5_1호
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    • pp.455-467
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    • 2017
  • 초분광 영상을 이용한 표적 탐지를 수행할 때에는 인접한 분광 밴드의 중복성의 문제 및 고차원 데이터로 인해 발생하는 방대한 계산량의 문제점을 해결하기 위한 특징 추출 과정이 필수적이다. 본 연구는 기계 학습 분야의 특징 선택 기법을 초분광 밴드 선택에 적용하기 위해 $L_{2,1}$-norm regression 모델을 이용한 새로운 밴드 선택 기법을 제안하였으며, 제안한 밴드 선택 기법의 성능 분석을 위해 표적이 존재하는 초분광영상을 직접 촬영하고 이를 바탕으로 표적 탐지를 수행한 결과를 분석하였다. 350 nm~2500 nm 파장 대역에서 밴드 수를 164개에서 약 30~40개로 감소시켰을 때 Adaptive Cosine Estimator(ACE) 탐지 성능이 유지되거나 향상되는 결과를 보였다. 실험 결과를 통해 제안한 밴드 선택 기법이 초분광 영상에서 탐지에 효율적인 밴드를 추출해 내며, 이를 통해 성능의 감소 없이 데이터의 차원 감소를 수행할 수 있어 향후 실시간 표적 탐지 시스템의 처리 속도 향상에 도움을 줄 수 있을 것으로 보인다.

SNS를 통한 네일샵의 활용실태 및 SNS 정보 신뢰도가 네일샵 선택요인에 미치는 영향 (The effect of reliability of Social Media information on the selection factors of nail shops according to the use of nail shops through Social Media)

  • 함현지;이재남;이은선
    • 한국응용과학기술학회지
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    • 제41권3호
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    • pp.842-855
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    • 2024
  • 본 연구에서는 20~50대 성인 여성을 대상으로 SNS를 통한 네일샵의 활용실태 및 SNS 정보 신뢰도와 네일샵 선택요인에 미치는 영향을 알아보고, SNS를 통한 효과적인 홍보를 통하여 고객 만족과 충성고객 확보 및 네일업계의 경영전략에 기여 하고자 연구를 진행하였다. 설문 조사는 SNS를 사용하며 네일샵을 이용해 본 20~50대 성인 여성을 대상으로 최종 403부를 분석하여 사용하였다. 연구 결과, 일반적 특성에 따른 SNS를 통한 네일샵의 이용실태에서는 각 요인에 따라 차이가 있는 것으로 나타났으며, SNS를 통한 네일샵 이용실태에 따른 정보 신뢰도와 SNS 네일샵 선택요인, 네일샵 SNS 활용에 따른 SNS 정보 신뢰도, 네일샵 선택요인에 차이가 있는 것으로 나타났다. 또한, SNS 정보 신뢰도가 SNS를 통한 네일샵 선택요인에 영향을 미치는 것으로 나타났다. 본 연구는 네일샵 경영전략 수립을 위한 마케팅의 기초자료 및 네일샵을 이용하는 소비자들의 만족도를 높여 네일 미용 시장의 활성화에 도움이 될 수 있을 것이다.

메타분석의 선택 편향 보정을 위한 쌍별 유사가능도 접근법 (Pairwise pseudolikelihood approach for adjusting selection bias in meta-analysis)

  • 국성희;이우주
    • 응용통계연구
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    • 제33권4호
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    • pp.439-449
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    • 2020
  • 메타 분석은 여러 연구 결과들을 종합시켜주는 분석 방법 중 하나이다. 이 때 수집되는 연구 문헌들은 소규모 연구인 경우 통계적으로 유의한 결과를 보이는 연구가 출간될 확률이 높기 때문에, 선택 편향의 특수한 경우인 출판 편향이 종종 발생한다. 선택 편향을 보정하는 방법에는 조건부 가능도와 가중 추정 방정식이 있는데 이 방법들은 실제 얻기 힘든 정확한 선택 확률 모형을 필요로한다. 반면 쌍별 유사가능도 접근법은 선택 확률 모형을 정확히 알 수 없는 경우에도 선택 편향을 보정할 수 있는 방법으로 제안되었다. 본 논문은 메타분석에서 쌍별 유사가능도 접근법의 성능과 문제점을 수치적으로 연구한다.

A Comparative Study of Korean and the US College Female Students′ Clothing Buying Behavior

  • Hwang, Choon-Sup;Kim, Sun-Ah
    • International Journal of Costume and Fashion
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    • 제4권
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    • pp.47-61
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    • 2004
  • This study analyzed the buying patterns of American and Korean female college students in terms of criteria for clothing selection; store preferences; criteria for store selection; fashion information sources; expressions of customer dissatisfaction; purchasing frequency and motivations for purchasing clothes. The study was implemented through self-administered questionnaires which were back translated for validity. The samples consisted of 730 female college students majoring in the fields related to clothing and textiles: 310 U.S. and 412 Korean students. Likert scales were used for most measures with 1=never or very unimportant and 5=always or very important. Data were analyzed by factor analysis, analysis of covariance, Duncans multiple comparison, and t-test. Results are as follows: 1) Design factor was the most important criteria in clothing selection with no differences between country groups. There were, however, significant differences for psychological exhibition factors, practical and economic factors. 2) Both groups preferred specialty and department stores, with department stores more popular in Korea. 3) Merchandise was the most important store selection criterion and fashion magazines and self-experience were rated as the most important information sources for the both groups. 4) Korean group expressed their dissatisfaction with and observable problem with a product before purchase more often than U.S. group, but the U.S. group was more vocal about color loss or shrinkage after care procedures. 5) Some clear differences between the two countries emerged. Marketers targeting American consumers should pay more attention to practicality and service; to Korean consumers more symbolic meaning of products.

Use of In Vivo and In Vitro Systems to Select Leishmania amazonensis Expressing Green Fluorescent Protein

  • Costa, Solange Dos Santos;Golim, Marjorie De Assis;Bergmann, Bartira Rossi;Costa, Fabio Trindade Maranhao;Giorgio, Selma
    • Parasites, Hosts and Diseases
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    • 제49권4호
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    • pp.357-364
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    • 2011
  • Various Leishmania species were engineered with green fluorescent protein (GFP) using episomal vectors that encoded an antibiotic resistance gene, such as aminoglycoside geneticin sulphate (G418). Most reports of GFP-Leishmania have used the flagellated extracellular promastigote, the stage of parasite detected in the midgut of the sandfly vector; fewer studies have been performed with amastigotes, the stage of parasite detected in mammals. In this study, comparisons were made regarding the efficiency for in vitro G418 selection of GFP-Leishmania amazonensis promastigotes and amastigotes and the use of in vivo G418 selection. The GFP-promastigotes retained episomal plasmid for a prolonged period and G418 treatment was necessary and efficient for in vitro selection. In contrast, GFP-amastigotes showed low retention of the episomal plasmid in the absence of G418 selection and low sensitivity to antibiotics in vitro. The use of protocols for G418 selection using infected BALB/c mice also indicated low sensitivity to antibiotics against amastigotes in cutaneous lesions.

소비자의 추구혜택에 따른 수산물 가공식품의 선택속성에 관한 연구 (Fishery Products Processed Food Research for Reference of Selection and Pursuable Benefit of Fishery Products Processed Food)

  • 김종성;하규수
    • 한국벤처창업학회:학술대회논문집
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    • 한국벤처창업학회 2010년도 통합학술대회
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    • pp.93-112
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    • 2010
  • Consumers show higher interest in fishery products processed food that are effective for the personal health and good for convenience, nourishment and taste. But current domestic research for fishery products processed food is marginal. In this respect, this research systematically analyzes consumers' consumption patterns and relationship to comsumer's pursuable benefit, reference for selection, satisfaction level and purpose of purchase. This research shows results as following. Consumers consider product information the most important in reference for selection, and convinience the highest in pursuable benefit. And this research analyze influence of reference for selection and pursuable benefit on satisfaction level and purpose of purchase using demographic properties as control variables. The variables which affect satisfaction level are residential district(region), recipe, nutrient, convenience, economy and the variables affect purpose of purchase are nutrient, convenienct, satisfaction level. If this result is used to develop new products and industrialize fishery products processed food, consumer market of fishery products processed food can be expanded. And this result can be utilized as fundamental reference for sales promotion.

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Optimal Ball-end and Fillet-end Mills Selection for 3-Axis Finish Machining of Point-based Surface

  • Kayal, Prasenjit
    • International Journal of CAD/CAM
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    • 제7권1호
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    • pp.51-60
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    • 2007
  • This paper presents an algorithm of optimal cutting tool selection for machining of the point-based surface that is defined by a set of surface points rather than parametric polynomial surface equations. As the ball-end and fillet-end mills are generally used for finish machining in a 3-axis computer numerical control machine, the algorithm is applicable for both cutters. The optimum tool would be as large as possible in terms of the cutter radius and/or corner radius which maximise (s) the material removal rate (i.e., minimise (s) the machining time), while still being able to machine the entire point-based surface without gouging any surface point. The gouging are two types: local and global. In this paper, the distance between the cutter bottom and surface points is used to check the local gouging whereas the shortest distance between the surface points and cutter axis is effectively used to check the global gouging. The selection procedure begins with a cutter from the tool library, which has the largest cutter radius and/or corner radius, and then adequacy of the point-density is checked to limit the accuracy of the cutter selection for the point-based surface within tolerance prior to the gouge checking. When the entire surface is gouge-free with a chosen cutting tool then the tool becomes the optimum cutting tool for a list of cutters available in the tool library. The effectiveness of the algorithm is demonstrated considering two examples.

Bit Error Rate of Underlay Decode-and-Forward Cognitive Networks with Best Relay Selection

  • Ho-Van, Khuong;Sofotasios, Paschalis C.;Alexandropoulos, George C.;Freear, Steven
    • Journal of Communications and Networks
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    • 제17권2호
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    • pp.162-171
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    • 2015
  • This paper provides an analytic performance evaluation of the bit error rate (BER) of underlay decode-and-forward cognitive networks with best relay selection over Rayleigh multipath fading channels. A generalized BER expression valid for arbitrary operational parameters is firstly presented in the form of a single integral, which is then employed for determining the diversity order and coding gain for different best relay selection scenarios. Furthermore, a novel and highly accurate closed-form approximate BER expression is derived for the specific case where relays are located relatively close to each other. The presented results are rather convenient to handle both analytically and numerically, while they are shown to be in good agreement with results from respective computer simulations. In addition, it is shown that as in the case of conventional relaying networks, the behaviour of underlay relaying cognitive networks with best relay selection depends significantly on the number of involved relays.