• 제목/요약/키워드: two-stage cluster analysis

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LuxR-Type SCO6993 Negatively Regulates Antibiotic Production at the Transcriptional Stage by Binding to Promoters of Pathway-Specific Regulatory Genes in Streptomyces coelicolor

  • Tsevelkhoroloo, Maral;Li, Xiaoqiang;Jin, Xue-Mei;Shin, Jung-Ho;Lee, Chang-Ro;Kang, Yup;Hong, Soon-Kwang
    • Journal of Microbiology and Biotechnology
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    • 제32권9호
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    • pp.1134-1145
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    • 2022
  • SCO6993 (606 amino acids) in Streptomyces coelicolor belongs to the large ATP-binding regulators of the LuxR family regulators having one DNA-binding motif. Our previous findings predicted that SCO6993 may suppress the production of pigmented antibiotics, actinorhodin, and undecylprodigiosin, in S. coelicolor, resulting in the characterization of its properties at the molecular level. SCO6993-disruptant, S. coelicolor ΔSCO6993 produced excess pigments in R2YE plates as early as the third day of culture and showed 9.0-fold and 1.8-fold increased production of actinorhodin and undecylprodigiosin in R2YE broth, respectively, compared with that by the wild strain and S. coelicolor ΔSCO6993/SCO6993+. Real-time polymerase chain reaction analysis showed that the transcription of actA and actII-ORF4 in the actinorhodin biosynthetic gene cluster and that of redD and redQ in the undecylprodigiosin biosynthetic gene cluster were significantly increased by SCO6993-disruptant. Electrophoretic mobility shift assay and DNase footprinting analysis confirmed that SCO6993 protein could bind only to the promoters of pathway-specific transcriptional activator genes, actII-ORF4 and redD, and a specific palindromic sequence is essential for SCO6993 binding. Moreover, SCO6993 bound to two palindromic sequences on its promoter region. These results indicate that SCO6993 suppresses the expression of other biosynthetic genes in the cluster by repressing the transcription of actII-ORF4 and redD and consequently negatively regulating antibiotic production.

학생 교육지원의 효율적 운영에 대한 단계적 벤치마킹 방안 연구 (A Study on the Stepwise Benchmarking Method for Efficient Operation of Student Education Support)

  • 정규한;이장희
    • 실천공학교육논문지
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    • 제12권1호
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    • pp.213-230
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    • 2020
  • 지금까지 학교 교육은 교육 예산 및 시설, 프로그램 등이 다양하게 투입되었지만 그 성과 평가는 명확하게 이루어지지 못했다. 본 연구는 전국 고등학교에서 학생들을 위한 교육 지원의 효율성을 분석하는 모델을 제시하였다. 학생 교육지원이 비슷한 학교의 운영 효율성을 분석하기 위하여 1차적으로 EM 군집분석을 수행한 후, 군집별로 상대적 효율성을 Network DEA를 이용하여 분석하였다. 본 연구에서 Network DEA는 학교 인프라 측면의 6개 투입요소, 1차적 산출 요소인 학업지속자, 학교 프로그램 측면의 10개 2차 투입 요소, 2차적 산출 요소인 진학자와 취업자, 연결 변수인 1인당도서관이용률을 고려하여 분석하였다. 효율성 분석 결과를 기반으로 벤치마킹할 대상을 선정하기 위해 유클리드 거리 계산방법을 적용하여 Tier분석을 수행하였다. 본 연구에서는 전국의 일반계고등학교와 직업계고등학교에서의 학생 교육지원 데이터를 수집하여 교육 지원의 효율성을 분석하는 모델을 적용하였다. 단계적 벤치마킹방안은 벤치마킹 대상 선택의 문제점을 보완하기 위해 비효율적인 학교의 요소를 고려하여 단계적으로 효율성 개선 대상을 선정하도록 제안하였다. 학생 교육지원 효율성이 낮은 학교가 학생 교육지원의 효율적 운영을 위한 단계적 벤치마킹을 하는데 기초적 자료로 활용될 것으로 기대된다.

이단계 군집분석에 의한 농촌관광 편의시설 유형별 소비자 선호 결정요인 (Determinants of Consumer Preference by type of Accommodation: Two Step Cluster Analysis)

  • 박덕병;윤유식;이민수
    • 마케팅과학연구
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    • 제17권3호
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    • pp.1-19
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    • 2007
  • 본 연구에서는 농촌관광 방문객에게 제공되는 편의시설을 유형화하고 어떤 특징을 가진 방문객이 어떤 편의시설을 선호하는지를 규명하기 위한 방법과 그 분석결과를 제시하였다. 이를 위하여 우선 2단계 군집분석법을 사용하여 농촌관광 편의시설을 유형화하였다. 그 다음으로 군집분석에 사용되는 변인이 범주형 변인이 있을 경우 전통적인 군집분석 방법을 적용할 수 없기 때문에 2단계 군집분석을 하였다. 본 연구는 2단계 군집분석법이 범주형 변인으로 측정된 농촌관광의 편의시설을 유형화하는 데 매우 유용하다는 것을 보여 주고 있다. 다중로짓 모형을 사용하여 특정 편의시설 유형을 선호할 확률에 영향을 미치는 농촌관광 방문자의 사회인구학적 특성과 여행특성을 규명하였다. 즉, 다중로짓 모형을 통해 참조항(일반농가형)으로 설정된 편의시설 유형에 비해 특정 편의시설을 선호할 확률에 영향을 미치는 소비자의 특성을 규명할 수 있다는 것이 본 연구의 특징이다.

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웹 정보원의 동시인용분석에 관한 실험적 연구 (An Experimental Study of Cocitation Analysis on Web Information)

  • 정동열;최윤미
    • 정보관리학회지
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    • 제16권2호
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    • pp.7-26
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    • 1999
  • 본 연구는 계량정보학적 분석방법을 웹 정보원에 적용하여 커뮤니케이션 분야의 웹 정보원에 대한 동시인용분석을 실험적으로 실시하고 있다. 특정 학문분야의 지적구조를 규명하기 위하여 링크 건수를 기준으로 선정된 웹 정보원을 대상으로 동시인용빈도, 상관계수행렬, 다차원축적기법과 군집분석 등 동시인용분석 기법을 적용하고 있다. 분석대상이 인쇄문헌에 적용되어 온 분석기법이 웹 정보원에 적용될 수 있음을 규명하고 있다. 아울러 동시인용분석에서 인쇄문헌과 웹 정보원이 갖는 특성과 연구방법상의 차별성 등을 분석한다.

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Colorectal Cancer Staging Using Three Clustering Methods Based on Preoperative Clinical Findings

  • Pourahmad, Saeedeh;Pourhashemi, Soudabeh;Mohammadianpanah, Mohammad
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권2호
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    • pp.823-827
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    • 2016
  • Determination of the colorectal cancer stage is possible only after surgery based on pathology results. However, sometimes this may prove impossible. The aim of the present study was to determine colorectal cancer stage using three clustering methods based on preoperative clinical findings. All patients referred to the Colorectal Research Center of Shiraz University of Medical Sciences for colorectal cancer surgery during 2006 to 2014 were enrolled in the study. Accordingly, 117 cases participated. Three clustering algorithms were utilized including k-means, hierarchical and fuzzy c-means clustering methods. External validity measures such as sensitivity, specificity and accuracy were used for evaluation of the methods. The results revealed maximum accuracy and sensitivity values for the hierarchical and a maximum specificity value for the fuzzy c-means clustering methods. Furthermore, according to the internal validity measures for the present data set, the optimal number of clusters was two (silhouette coefficient) and the fuzzy c-means algorithm was more appropriate than the k-means clustering approach by increasing the number of clusters.

Citizen Awareness of the Smart City: A Study of Khon Kaen, Thailand

  • KAMNUANSILPA, Peerasit;LAOCHANKHAM, Sirisak;CRUMPTON, Charles David;DRAPER, John
    • The Journal of Asian Finance, Economics and Business
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    • 제7권7호
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    • pp.497-508
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    • 2020
  • Using primary data collected through semi-structured interviews conducted during February 2019, this article examines citizen's awareness and knowledge of Khon Kaen Smart City (KKSC) among the residents of five contiguous municipalities within Khon Kaen Province, Thailand. A self-weighted sample of 420 respondents was selected through a two-stage, 30-cluster sampling process. In the first stage, a sample of 30 artificial clusters of 100 households each was selected. In the second, 14 households were randomly selected from each of these clusters. The head of household or, if unavailable, a resident aged 18 or over was interviewed. The study applies the "citizens as democratic participants" dimension of Simonofski et al.'s (2019) evaluative framework. Results found that, because of ineffective citizen engagement, the levels of awareness and knowledge about KKSC were low. However, multiple logistic regression found that, despite the low levels of awareness and knowledge, education and income could establish an independent effect on awareness of KKSC. Those who completed post-secondary school were more aware of KKSC than those who finished only secondary or primary education. Similarly, the analysis of data clearly indicated that educational attainment, solely and independently from all other socio-economic and demographic variables, could explain the positive effect of education on knowledge about KKSC.

The Effect of Sharia Destination Image on Developing Post-Visit Behavior: A Case Study in Indonesia

  • MARLIZAR, Marlizar;LUBIS, Abdul Rahman;UTAMI, Sorayanti;CHAN, Syafruddin
    • The Journal of Asian Finance, Economics and Business
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    • 제8권4호
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    • pp.959-969
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    • 2021
  • This study aims to develop new constructs and indicators for sharia destination image, and then examine its effects on perceived value, tourist satisfaction, and post-visit behaviour. Furthermore, it analyses the mediating role of perceived value and tourist satisfaction on relationship between sharia destination image and post-visit behaviour. The population were domestic and Malaysian Muslim tourists who visited Aceh during the study period. The sampling was carried out in two stages. The first stage involved selecting most visited districts. The second stage involved randomly selecting tourists who visit during the study period in the districts. Data was collected using a structured questionnaire with a Likert scale. Also, a total of 270 questionnaires were distributed to domestic and Malaysian tourists in Aceh. Cluster sampling was used to determine the sample area, and purposive sampling technique was used to determine the study sample. Furthermore, the data analysis technique is Structural Equation Modelling. The results showed that the sharia destination image has a significant effect on perceived value. Meanwhile, the perceived value significantly influenced tourist satisfaction and post-visit behaviour. In addition, the perceived value and tourist satisfaction can mediate the effects of sharia destination image, which has no direct effect on post-visit behaviour.

군집분석과 상세기상모델을 통한 포항지역 계절별 바람장 특성 (The Characteristics of Seasonal Wind Fields around the Pohang Using Cluster Analysis and Detailed Meteorological Model)

  • 정주희;오인보;고대권;김유근
    • 한국환경과학회지
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    • 제20권6호
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    • pp.737-753
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    • 2011
  • The typical characteristics of seasonal winds were studied around the Pohang using two-stage (average linkage then k-means) clustering technique based on u- and v-component wind at 850 hpa from 2004 to 2006 (obtained the Pohang station) and a high-resolution (0.5 km grid for the finest domain) WRF-UCM model along with an up-to-date detailed land use data during the most predominant pattern in each season. The clustering analysis identified statistically distinct wind patterns (7, 4, 5, and 3 clusters) representing each spring, summer, fall, and winter. During the spring, the prevailed pattern (80 days) showed weak upper northwesterly flow and late sea-breeze. Especially at night, land-breeze developed along the shoreline was converged around Yeongil Bay. The representative pattern (92 days) in summer was weak upper southerly flow and intensified sea-breeze combined with sea surface wind. In addition, convergence zone between the large scale background flow and well-developed land-breeze was transported around inland (industrial and residential areas). The predominant wind distribution (94 days) in fall was similar to that of spring showing weak upper-level flow and distinct sea-land breeze circulation. On the other hand, the wind pattern (117 days) of high frequency in winter showed upper northwesterly and surface westerly flows, which was no change in daily wind direction.

엠파이어 시대의 드레스 재현을 위한 형태분석 및 패턴연구 (Analysis of Dress Style and Patterns for the Reproduction of Empire Style Dress)

  • 이정란;정재민;조윤주
    • 한국의류산업학회지
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    • 제8권6호
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    • pp.687-696
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    • 2006
  • This study aims at analyzing the silhouette, dress patterns and detail of Empire Era(1789-1825), and making use of this results for the modern stage costume construction. The dresses of Empire era were divided into X and H style. The results revealed that the bust girth of X style group was bigger than that of H style group. Such patterns as high waistline, puff sleeve, train, etc. which appeared during the peak time of Empire style period were more remarkable for H style group. This obviously indicated that more epical characteristics were observed for H style group than for X style group. Similarly to silhouette analysis, based on the results from cluster analysis conducted to put similar groups together, two groups were formed - a visually differentiated and complex group and a simple group in the absence of detail. Most dress details from Empire period had simple embellishments. Comparison of the average size of the patterns between two groups indicated that waist front length of H style was shorter than that of X style. Front interscye was even greater than back width for both groups. Such trend was quite different from today's pattern in which back width is larger than front width based on body measurements. Preference for big breast during the period was reflected on dress patterns and the side length of front side goes across the back much further for bodice patterns. Two representatives were selected and reproduced using materials similar to those of real dresses of Empire style, following two times fit test.

Ambient Air Concentrations of Benzene, Toluene, Ethylbenzene and Xylene in Bangkok, Thailand during April-August in 2007

  • Laowagul, Wanna;Garivait, Hathairatana;Limpaseni, Wongpun;Yoshizumi, Kunio
    • Asian Journal of Atmospheric Environment
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    • 제2권1호
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    • pp.14-25
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    • 2008
  • Benzene, toluene, ethyl benzene and m-, p-, and o-xylene, the most influential aromatic volatile organic compounds (VOCs), were measured in Bangkok, Thailand, one of the most rapidly developing urban areas in Southern East Asia. The purpose of this study is to characterize the ambient air quality with respect to above mentioned aromatic compounds. The data were monitored in ten sites which cover roadside area, residential area and background area. Canister technique was used to obtain air sample at 24 hour interval per a month during April-August in 2007. GC/MS with three stage preconcentrator was used to analyze these samples. The average concentrations of benzene, toluene, ethyl benzene m-, p-xylene and o-xylene are 5.8, 36.1, 4.1, 11.0 and $3.7{\mu}g/m^3$, respectively. They were observed to be distributed in a log-normal form. Moreover, o-xylene and m, p-xylene exhibited a very good correlation (r=0.976). The slope of the regression equation between them was 3.07 which consisted with a previous reported value. The average ratio of toluene to benzene was 6.4 in April, May June and August. This value was comparable to the ones measured in other Asian cities. Two types of statistical analyses, cluster and factor analyses, were applied to the data in this study. Well characterization was made to understand the air quality of Bangkok area.