• 제목/요약/키워드: selection

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사업자 사전 선택제 도입 사례와 시사점

  • 유영상
    • 한국기술혁신학회:학술대회논문집
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    • 한국기술혁신학회 2002년도 추계학술대회
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    • pp.45-57
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    • 2002
  • Since a new entrant in the telecommunications market requires time in order to construct its own network, a requirement on the incumbent operator to implement carrier selection and pre-selection can enable a new entrant to immediately attract customers and earn revenue. Carrier selection can normally be accomplished in two ways, on a call-by-call basis or through carrel pre-selection. Call-by-call selection allows customers to choose a new entrant rather than the incumbent carrier using a specific code designated to the new carrier each time a call is made. Carrier Pre-Selection, on the other hand, allows customers directly connect to the network of one provider to have access automatically to another company's services when they pick up the phone to make certain types of calls. The carrier pre-selection option is generally considered to be a second regulatory step following the implementation of the call-by-call carrier selection option. Carrier pre-selection with the ability to override on a call-by-call basis for long distance, international, local, and fixed-to-mobile calls has now been implemented in many EU countries. This paper attempts to identify the issues in introducing CPS and to draw policy implications from other countries' experiences.

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자연치와 도재관에 대한 색조선택의 동일성 (Shade Matching Identification of in Vivo Natural Teeth and Porcelain-Fused-to-Metal Crowns)

  • 조홍규
    • 대한치과기공학회지
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    • 제29권1호
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    • pp.35-48
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    • 2007
  • The purpose of this study was to evaluate shade selection using conventional visual assessment in vivo natural teeth and porcelain-fused-to-metal (PFM) crown. Maxillary central incisors, lateral incisors and canines of one hundred twenty four college women were used as vivo natural teeth. Fifty one PFM crown for maxillary central incisor fabricated by dental laboratory were used as experimental materials. Using Vitapan Classical Shade Guides, shade selection of natural teeth was measured by each college woman and shade selection of PFM crown was measured by three ceramists with more than ten years career. Both natural teeth and PFM crown shade selection were measured through Shade Eye-Ex. From the shade selection comparing, following results were obtained. The results were as follows: 1. The shade matching identification of natural teeth between the shade selection using Vitapan Classical Shade Guides and the shade selection using Shade Eye-Ex was 27.4% in maxillary central incisor, 13.7% in lateral incisor and 18.5% in canine. 2. Among the shade selection of PFM crown by three ceramists, the shade evaluation of three ceramists were same only in ten cases. In twenty case, those of two ceramists were same. 3. The shade matching identification of PFM crown between the shade selection using Vitapan Classical Shade Guides and the shade selection using Shade Eye-Ex was 38.6% in average. These results suggest that the shade selection using conventional visual assessment should be dealt with care in clinic and need a credible method for shade matching color.

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WAVE 시스템에서 선택 다이버시티를 위한 선택 기준에 대한 연구 (A Study on Selection Criterions for Selection Diversity in WAVE Systems)

  • 홍대기
    • 반도체디스플레이기술학회지
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    • 제14권2호
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    • pp.9-16
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    • 2015
  • In this paper, selection criterions on selection diversity are researched. The diversity is applied to the multiple antenna system based on wireless access in vehicular environment (WAVE) standard for rapid varying channel. Least squares (LS) based decision feedback equalizer (DFE) are used for channel equalization. Received signal is regenerated by means of the decision feedback path. In the selection diversity, the regenerated signal as well as the received signal is selected according to selection criterion. The decision feedback algorithm can follow the fast speed of WAVE fading channel. To control the tracking speed of the time-varying channel, simple low pass filter is used. Finally, the estimated channel value recovers the distorted payloads. Signal power before automatic gain control (AGC) in analog stage can be used as a selection criterion. In the digital stage, signal power after AGC, noise power after AGC, signal to noise ratio after AGC and cross-correlation method can be used as selection criterions. According to the simulation results, the performance of the selection diversity is improved in comparison with that of the combining diversity for the WAVE fading channel.

사각형강목의 끝자루를 이용한 트롤어구의 어획선택성 연구 ( I ) - 사각형강목의 어획선택성 - ( Studies on the Selectivity of the Trawl Net With the Square Mesh Cod-End ( 1 ) - Selectivity of the Square Mesh Cod-End - )

  • 이주희;김삼곤;김진건
    • 수산해양기술연구
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    • 제30권3호
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    • pp.161-171
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    • 1994
  • Mesh selection analysis for the trawl net were carried out at the Southern Korean Sea and the East China Sea during the 1992-1994 years by the training ship Seabada of the National Fisheries University of Pusan, using A type (51.2mm), B type (70.2mm), C type (77.6mm), D type (88.0mm) square mesh cod-ends. The fishing trials were made using bottom trawl of the trouser type cod-end with cover net. Selection curves and selection parameters were calculated by a logistic model for Sphyraena pinguis, Pampus argenteus, Trachurus japonicus, Pagrus major, Callanthias japonicus, Trichiurus lepturus. The results obtained are summarized as follows: 1. Red barracuda : Selection range and fifty percent selection length in the A type was 115.8mm, 292.8mm, respectively. 2. Harvest fish : Each selection range and fifty percent selection length in the B. C. and D type was 37.7mm, 113.8mm : 40.1mm, 131.7mm and 64.8mm, 148.6mm, respectively. Selection parameters of master curve were : slope, 3.81 : intercept, -6.4. Optimum mesh size was 89.3mm. 3. Horse mackerel : Each selection range and fifty percent selection length in the A, B, C and D type was 43.0mm, 148.3mm : 60.7mm, 183.2mm, 214.5mm and 91.4mm, 254.9mm, respectively. Selection parameters of master curve were : slope 2.30 : intercept, -6.4. Optimum mesh size was 66.8mm. 4. Red seabrem : Selection range and fifty percent selection length in the D type was 42.7mm, 203.4mm, respectively. 5. Yellowsail red bass : Selection range and fifty percent selection length in the A type was 84.0mm, 110.6mm, respectively. 6. Hair tail : Each selection range and fifty percent selection length in the A, B and C type was 59.7mm, 176.0mm : 100.9mm, 250.7mm and 178.6mm, 307.0mm, respectively. Selection parameters of master curve were : slope, 1.54 : intercept, -5.4. Optimum mesh size was 57.5mm.

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Selection on milk production and conformation traits during the last two decades in Japan

  • Togashi, Kenji;Osawa, Takefumi;Adachi, Kazunori;Kurogi, Kazuhito;Tokunaka, Kota;Yasumori, Takanori;Takahashi, Tsutomu;Moribe, Kimihiro
    • Asian-Australasian Journal of Animal Sciences
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    • 제32권2호
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    • pp.183-191
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    • 2019
  • Objective: The purpose of this study was to compare intended and actual yearly genetic gains for milk production and conformation traits and to investigate the simple selection criterion practiced among milk production and conformation traits during the last two decades in Japan. Learning how to utilize the information on intended and actual genetic gains during the last two decades into the genomic era is vital. Methods: Genetic superiority for each trait for four paths of selection (sires to breed bulls [SB], sires to breed cows [SC], dams to breed bulls [DB], and dams to breed cows [DC]) was estimated. Actual practiced simple selection criteria were investigated among milk production and conformation traits and relative emphasis on milk production and conformation traits was compared. Results: Selection differentials in milk production traits were greater than those of conformation traits in all four paths of selection. Realized yearly genetic gain was less than that intended for milk production traits. Actual annual genetic gain for conformation traits was equivalent to or greater than intended. Retrospective selection weights of milk production and conformation traits were 0.73:0.27 and 0.56:0.44 for intended and realized genetic gains, respectively. Conclusion: Selection was aimed more toward increasing genetic gain in milk production than toward conformation traits over the past two decades in Japan. In contrast, actual annual genetic gain for conformation traits was equivalent to or greater than intended. Balanced selection between milk production and conformation traits tended to be favored during actual selection. Each of four paths of selection (SB, SC, DB, and DC) has played an individual and important role. With shortening generation interval in the genomic era, a young sire arises before the completion of sire's daughters' milk production records. How to integrate these four paths of selection in the genomic era is vital.

의사결정나무에서 분리 변수 선택에 관한 연구 (A Study on Selection of Split Variable in Constructing Classification Tree)

  • 정성석;김순영;임한필
    • 응용통계연구
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    • 제17권2호
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    • pp.347-357
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    • 2004
  • 의사결정나무에서 분리 변수를 선택하는 것은 매우 중요한 일이다. C4.5는 변수 선택에 있어 연속형 변수로의 변수 선택 편의가 심각하고, QUEST는 연속형 변수와 관련해서 정규성 가정이 위반될 경우 변수 선택력이 떨어진다. 본 논문에서는 통계적 로버스트 검정 알고리즘을 제안하고, 모의 실험을 통하여 C4.5, QUEST그러고 제안된 알고리즘의 효율성을 비교하였다. 실험 결과 제안된 알고리즘이 변수 선택 편의와 변수 선택력 측면에서 로버스트함을 알 수 있었다.

경제동물의 주요 경제형질에 대한 표지인자를 이용한 선발(MAS)의 효율성 (Efficiency of Marker Assisted Selection(MAS) over The Phenotypic Selection for Economic Traits in Economic Animals)

  • 전광주
    • Journal of Animal Science and Technology
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    • 제44권6호
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    • pp.669-676
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    • 2002
  • 유전표지인자를 이용한 선발(marker assisted selection; MAS)과 전통적인 표현형기록에 근거한 반응의 비교분석을 위하여 고정효과모델(deterministic model)을 이용하여 시뮬레이션을 하였다. 자신의 단일 기록을 이용한 경우와 자신의 기록과 자신의 표지인자 정보를 이용할 경우 유전력이 높을수록 MAS의 효율성이 38%정도 높게 나타났다. 그러나 유전력이 높은 경우(50%) MAS의 효율성은 약 1%정도로서 효율성이 대단히 낮은 것으로 나타났다. 자신의 기록과 부모의 표현형 정보에 표지인자 정보를 추가할 경우 MAS의 효율성은 27% 정도였으며 마찬가지로 유전력이 높은 경우에는 효율성이 0에 가깝게 나타났다. MAS의 효율성은 유전력이 낮을수록 그리고 이용한 표지인자의 유전적 변이가 클수록 효율성이 높아지는 것으로 나타났다.

성인의 시판 라면류 선택 속성에 따른 식사 행동 차이에 대한 탐색적 고찰 (A Comprehensive Study on the Meal Intake Behavior according to Ramyun's Selection Attributes for Korean Adults)

  • 정효선;유경진;윤혜현
    • 동아시아식생활학회지
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    • 제22권6호
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    • pp.895-902
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    • 2012
  • This study was conducted to understand the Ramyun's selection attributes of Korean adults and examine differences in demographic characteristics and meal intake behavior among three groups of samples divided based on the Ramyun's selection attributes. Self-administered questionnaires were completed by 702 adults, and data were subjected to frequency analysis, chi-square analysis, factor analysis, reliability tests, cluster analysis, and discriminant analysis using SPSS. The results of the study were as follows. The Ramyun's selection attributes for Korean adults investigated were food quality (four variables), price (three variables), and company reliability (four variables). Cluster analysis resulted in the subjects being divided into three groups according to their Ramyun's selection attributes, a high-selection group, mid-selection group, and low-selection group. Three groups of samples classified by Ramyun's selection attributes differed based on demographic characteristics (gender and education level) and meal intake behavior (meal numbers, reason for meal, meal time, and meal size).

Criteria for Supplier Selection in Textile and Apparel Industry : A Case Study in Vietnam

  • NONG, Nhu-Mai Thi;HO, Phong Thanh
    • The Journal of Asian Finance, Economics and Business
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    • 제6권2호
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    • pp.213-221
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    • 2019
  • The study aims to investigate some criteria of supplier selection in the textile and apparel (T&A) sector in Vietnam. Most research on supplier selection criteria for T&A sector was mainly conducted based on the review of literature. Therefore, the purpose of this study is to explore these criteria based on a framework in which an integrated approach of qualitative and quantitative was employed. First, an in-depth interview was used to explore what supplier selection criteria T&A companies were utilized after the literature on supplier selection criteria had been reviewed. Next, a prequestionnaire was built and sent to some practitioners and experts for their revision. Then, a pilot survey of 31 T&A companies with numerous statistical tests was conducted to validate the questionnaire. Finally, an official study of 282 respondents was conducted to determine supplier selection criteria which are best suited for T&A companies through exploratory factor analysis. The findings of the study suggest that there are eight supplier selection criteria including Quality, Cost, Delivery, Service, Capability, Company's image, Relationship, and Sourcing country. Each criterion comprises certain sub-criteria to make the supplier selection criteria set more comprehensive. The findings will be a contribution to the selection process of T&A companies as they can utilize these criteria to select capable suppliers.

Comparison of different digital shade selection methodologies in terms of accuracy

  • Nursen Sahin;Cagri Ural
    • The Journal of Advanced Prosthodontics
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    • 제16권1호
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    • pp.38-47
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    • 2024
  • PURPOSE. This study aims to evaluate the accuracy of different shade selection techniques and determine the matching success of crown restorations fabricated using digital shade selection techniques. MATERIALS AND METHODS. Teeth numbers 11 and 21 were prepared on a typodont model. For the #11 tooth, six different crowns were fabricated with randomly selected colors and set as the target crowns. The following four test groups were established: Group C, where the visual shade selection was performed using the Vita 3D Master Shade Guide and the group served as the control; Group Ph, where the shade selection was performed under the guidance of dental photography; Group S, where the shade selection was performed by measuring the target tooth color using a spectrophotometer; and Group I, where the shade selection was performed by scanning the test specimens and target crowns using an intraoral scanner. Based on the test groups, 24 crowns were fabricated using different shade selection techniques. The ΔE values were calculated according to the CIEDE2000 (2:1:1) formula. The collected data were analyzed by means of a one-way analysis of variance. RESULTS. For the four test groups (Groups C, Ph, S, and I), the following mean ΔE values were obtained: 2.74, 3.62, 2.13, and 3.5, respectively. No significant differences were found among the test groups. CONCLUSION. Although there was no statistically significant difference among the shade selection techniques, Group S had relatively lower ΔE values. Moreover, according to the test results, the spectrophotometer shade selection technique may provide more successful clinical results.