• 제목/요약/키워드: h-Index

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DISTINGUISHING NUMBER AND DISTINGUISHING INDEX OF STRONG PRODUCT OF TWO GRAPHS

  • Alikhani, Saeid;Soltani, Samaneh
    • 호남수학학술지
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    • 제42권4호
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    • pp.645-651
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    • 2020
  • The distinguishing number (index) D(G) (D'(G)) of a graph G is the least integer d such that G has an vertex labeling (edge labeling) with d labels that is preserved only by a trivial automorphism. The strong product G ☒ H of two graphs G and H is the graph with vertex set V (G) × V (H) and edge set {{(x1, x2),(y1, y2)}|xiyi ∈ E(Gi) or xi = yi for each 1 ≤ i ≤ 2.}. In this paper we study the distinguishing number and the distinguishing index of strong product of two graphs. We prove that for every k ≥ 2, the k-th strong power of a connected S-thin graph G has distinguishing index equal two.

SiON 박막의 광학적 특성에 대한 연구 (The study of SiON thin film for optical properties.)

  • 김도형;임기주;김기현;김현석;성만영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.247-250
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    • 2001
  • We studied optical properties of SiON thin-film in the applications of optical waveguide. SiON thin-film was grown in $300^{\circ}C$ by PECVD(plasma enhanced chemical vapor deposition) system. The change of SiON thin-film composition and refractive Index was studied as a function of varying $NH_3$ gas flow rate. As $NH_3$ gas flow rate was increased, Quantity of N and refractive index were increased at the same time. By the results, we could form the SiON thin-film to use of a waveguide with refractive index of 1.6. We analyzed the conditions of the thin-film with FTIR(fourier transform infrared) and OES (optical emission spectroscopy). N-H bonding($3390cm^{-1}$ ) can be removed by thermal annealing. And we could observe the SiH bonding state and quantity by OES analysis in $SiH_4$

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오존처리시 Bromate생성에 미치는 온도 및 pH의 영향 (The Effect of Temperature and pH on Bromate Formation by Ozonation)

  • 이무강;김영철;최종원
    • 한국환경과학회지
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    • 제13권7호
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    • pp.667-674
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    • 2004
  • The objective of this study was to investigate the effects of pH and temperature on the formation of bromate, which is ozonation by-products, during ozonation. In this experiment, the operating parameters including pH 3 ~ 10 and temperature 15 ~ $30^{\circ}C$ were studied. Through the study for the bromate formation, reaction rate constant, and ozonation effect index on pH and temperature, the results obtained are as follows. At the same initial pH condition, the increase of pH shown similar trends even if the reaction variables such as temperature and reaction time of ozonation were exchanged. As pH and temperature were increasing, the bromate concentration was increased but bromine(HOBr+OBr) was decreased with increasing pH from 3 to 10. The activation energy(J/mol) for bromate formation decreased with increasing pH. The rate constants of bromate formation for the reaction of ozone and bromide, and ozone dosage coefficient$(K_{0})$ increased with temperature and pH. Ozonation effect index(OI) decreased with increasing temperature and pH.

저자 순위를 이용한 개인별 연구 성과 지수 산출에 관한 연구 (A Study on Evaluation of Ideces an Individual's Scientific Productivity Using Author Rank)

  • 김완종;노경란;서진이;이혜진
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2007년도 추계 종합학술대회 논문집
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    • pp.468-472
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    • 2007
  • 연구자 개인의 연구 성과를 측정하기 위한 연구는 2005년 Hirsch가 h-지수(index)를 제안하면서 이와 관련된 후속 논의가 매우 활발하게 진행되고 있다. h-지수를 변형시킨 g-지수도 각광을 받고 있다. 하지만 이들 지수의 경우 연구에 기여한 비율에 상관없이 해당 논문의 인용빈도만을 고려하여 지수가 정해진다는데 그 한계가 있다. 본 연구에서는 이 두 가지 지수의 단점을 보완하기 위해 각 지수에 저자의 기여도를 접목시킨 K-지수를 제안하고자 한다.

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Helicobacter pylori 감염과 사회경제적 요인에 대한 연구 (Relation between Helicobacter pylori Infection and Socioeconomic Status in Korean Adolescents)

  • 정민경;권영세;최현;최연호;홍윤철
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제3권1호
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    • pp.17-22
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    • 2000
  • 목 적: 우리 나라 청소년기 소아의 H. pylori 감염 유병율을 조사하고, 사회경제적 요인이 청소년의 H. pylori 감염에 어떠한 영향을 미치는지 알아보고자 하였다. 대상 및 방법: 1996년 10월 부천시에 살고 있는 10~15세의 532명(남아 285명, 여아 247명)의 소아를 대상으로 채혈을 시행하여 혈청학적인 방법(serum IgG antibody)으로 H. pylori 감염을 진단하였다. 설문지를 통하여 성별, 연령, Hollingshead index에 따라 분류한 사회경제적 수준, 주거형태(전세 또는 자가), 혼잡지수(crowding index)를 조사하였는데, 532명 중 375명(70.5%, 남:여=205:170)의 설문이 회수되었다. Hollingshead index는 부모의 교육정도와 직업을 고려하여 구분하였고 crowding index는 식구수/방수로 구하였다. 각각 단변수 회귀분석 후 의미있는 결과를 모아 다중회귀분석을 시행하였다. 결 과: H. pylori 유병률은 남아에서 17.1% (32/205), 여아에서 16.5% (28/170)로 통계적으로 유의한 차이는 없었다(P=0.88). 10~11세, 12~13세, 14~15세의 세 연령군으로 나누어 비교한 결과, 연령이 증가할수록 H. pylori 유병률은 각각 10.3% (7/68), 15.9% (25/157), 20.7% (31/150)로 유의한 증가를 보였다(P=0.05). 사회경제적 수준을 Hollingshead index로 구하여 세 군으로 나누어 비교한 결과, 사회경제적 수준이 높을수록 H. pylori 양성은 각각 20.0% (23/115), 16.0% (39/244), 6.3% (1/16)로 감소하는 역비례 관계를 보였으나 통계적으로 유의한 차이는 아니었다(P=0.16). 전세와 자가를 비교했을 때 H. pylori 양성은 각각 15.7% (22/140), 17.5% (41/235)로 유의한 차이가 없었다(P=0.66). 혼잡지수(crowding index: 식구수/방수)가 1.5 미만일 때 H. pylori 양성은 16.0% (26/163), 1.5 이상일 때 17.5% (37/212)로 유의한 차이가 없었다(P=0.70). 다중회귀분석 결과 H. pylori 감염에 대해 연령은 odds ratio 2.2 (95% confidence interval 0.9~5.4), Hollingshead index에 의한 사회경제적 수준은 odds ratio 3.6 (95% confidence interval 0.5~28.9)이었다. 결 론: 부천시 청소년기 소아의 H. pylori 감염유병률은 16.8%이며, 부모의 교육정도와 직업에 따른 사회경제적 수준이 가족내 혼잡도, 주거형태보다 감염에 더욱 영향을 미치는 것으로 보인다.

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The Effect of Bifidobacteria and Various Oligosaccharides Consumption on the Risk of Colon Cancer in Rats

  • Khil, Jin-Mo
    • Nutritional Sciences
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    • 제8권4호
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    • pp.219-225
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    • 2005
  • This study examined the effect of viable bifidobacteria and non-digestible carbohydrates on the cecal pH, colonic neoplastic lesion (aberrant crypt) and proliferating cell nuclear antigen (PCNA) labeling index in carcinogen-treated mts. Animals received s.c. injection of dimethylhydrazine (DMH) (15 mg/kg body weight) twice 3 days apart. Three days after the second carcinogen administration, the treatments were begun. 1he treatments were basal diet (AIN-76) with skim milk (Basal/skim), or the following diets with daily gavage of $10^8$ bifidobacteria: basal (Basal/bifido), $2\%$ fructo-oligosaccharide (FOS/bifido), $2\%$ soybean oligosaccharide (SBO/bifido), $2\%$ wheat bran oligosaccharide (WBO/bifido) and $8.4\%$ wheat bran (WB/bifido). After 4 weeks of treatment, cecal pH was measured using a pH probe. The number of aberrant crypt (AC), aberrant crypt foci (ACF) and crypt multiplicity were enumerated and colonic PCNA labeling index was determined using immunohistochemistry. Cecal pH was significantly reduced in SBO/bifido and FOS/bifido groups compared to control group. However, there were no significant differences in either number of AC or rates of cell proliferation as shown by PCNA labeling index among the groups, although mts fed FOS/bifido reduced the numbers of ACF compared to Basal/skim group. The SBO/bifido group did not reduce the number of ACF or PCNA labeling index. Also, other oligosaccharides did not reduce the risk of colon cancer compared to control group. The concomitant reduction of cecal pH and number of ACF suggest that the combination of bifidobacteria and FOS may reduce the risk of colon cancer.

An Index to Assess Overwork-Related Adverse Effects on Employees Under the Occupational Safety and Health Act in Taiwan

  • Yu-Cheng Lin;Yu-Wen Lin
    • Safety and Health at Work
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    • 제13권4호
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    • pp.401-407
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    • 2022
  • Background: The present study aimed to digitally evaluate the risk of overwork-related adverse effects (OrAEs) among employees from various occupational categories in Taiwan. Methods: Anonymous data of employees from seven companies/factories providing occupational health services were analyzed. The studied population comprised 5505 employees, and the data analyzed included employment duration, working hours, shift work schedules, and health checkup results. The risk for OrAEs was assessed by an index, Karo index (0-4, the larger the value, the higher the risk for OrAEs) obtained using a risk matrix made up of cardiocerebral and occupational risk factors. Karo index values of 3 and 4 were categorized as at high risk for OrAEs (h-OrAEs). Results: The 5505 employees had an average employment duration of 8.5 years and a mean age of 39.4 years. The prevalence rates for h-OrAEs of the seven companies/factories ranged from 3.9% to 34.2%. There were significant differences in prevalence rates for h-OrAEs between employees of retail stores and high-tech manufacturing factories. Multivariate analysis results indicated that workers of high-tech manufacturing factories had significantly higher risk for h-OrAEs compared with retail store workers. Conclusion: In terms of satisfying health risk management and legal requirements in Taiwan, the newly issued Karo index, which covers a wide range of occupational risk factors, can serve as an assessment and a warning tool for managing the risk of OrAEs in workplaces. To reduce risks for h-OrAEs, active and prudent control of cerebrocardiovascular risks and working hours is recommended.

깍두기의 이화학적 품질 지표와 관능적 지표간의 상관관계 (The Correlation of Physicochemical Quality Index and Sensory Index of Kakdugi)

  • 박소희;임호수
    • 한국조리학회지
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    • 제14권3호
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    • pp.136-142
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    • 2008
  • This study was conducted to investigate the correlation of the physicochemical quality index(pH, acidity, reducing sugar content and lactic acid bacterial count) and sensory index(sourness) of Kakdugi during the fermentation at 5$^{\circ}C$, 10$^{\circ}C$ and 20$^{\circ}C$ respectively. Also, the relations between physicochemical quality index and overall acceptability were carried out. The pH range, based on the middle sour intensity point of 4.5, was 5.75 at 5$^{\circ}C$ fermentation, whereas that was 4.2 at 10$^{\circ}C$ and 20$^{\circ}C$ fermentation. The pH showing the highest overall acceptability decreased along with increased fermentation temperature. The reduced sugar content decreased rapidly up to 0.9% acidity, but after that, decreased slowly from more than 0.9% acidity at all fermentation temperatures. With increased fermentation temperature, the reduced sugar content showing the highest overall acceptability also showed the decreasing tendency. Change patterns of lactic acid bacterial count and sourness didn't coincided at 5$^{\circ}C$ fermentation, whereas those did at 10$^{\circ}C$ and 20$^{\circ}C$ fermentation. The indexes showing high significant correlations with sourness of Kakdugi fermented at 5$^{\circ}C$ were not pH and lactic acid bacterial count but acidity and reducing sugar content(p<0.05). The sourness of Kakdugi fermented at 10$^{\circ}C$ and 20$^{\circ}C$ showed high significant correlations with all of the physicochemical index(p<0.05).

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3-h CPM 차동 검파기의 오율 성능 개선 (On the Improvement of Error Performance in the Differential Detector for 3-h CPM)

  • 홍의식;한영열
    • 한국통신학회논문지
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    • 제17권3호
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    • pp.240-246
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    • 1992
  • In the paper, the differential detection techniques of 3-h CPM signals whose modulation index is varied periodically are proposed and their error performances are analyzed. We select the modulation index sets which are proper to the differential detection and propose the differential detectors which detect symbol with 3 bits per smapling period of 3T and detect a bit per sampling period of T. Applying the nonredundant error correction circuit and viterbi algorithm to differential detection of 3-h CPM. We ascertain the error performances are improved.

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낙엽송과 잣나무림(林)의 수고성장곡선(樹高成長曲線) 및 지위지수(地位指數)에 관(關)한 연구(研究) (Site Index and Height Growth Curve of Larix leptolepis and Pinus koraiensis)

  • 조현서;정영관
    • 한국산림과학회지
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    • 제68권1호
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    • pp.11-17
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    • 1985
  • 지위지수(地位指數)의 사정(査定)의 기초(基礎)가 되는 수고생장곡선(樹高生長曲線)을 작성(作成)하기 위하여 수고(樹高)(H)를 수령(樹令)(A)의 함수(凾數)로 표시(表示)한 10개(個)의 모형(模型)을 수용(授用)한 결과(結果) $H=K-ab^A$식(式)이 가장 적합(適合)한 것으로 나타났다. 이 모형(模型)에 따라 낙엽송림(林)의 수고추정식(樹高推定式) $H=28.364-26.125(0.818)^A$ ($R^2=0.999$)와 잣나무림(林)의 수고추정식(樹高推定式) $H=26.331-25.125(0.886)^A$ ($R^2=0.999$)를 각각 도출(導出)하였다 그 다음, 추정(推定)된 수고생장곡선(樹高生長曲線)에 의하여 Bryant 법(法)의 계산과정(計算過程)을 거쳐 두 수종(樹種)의 지위지수표(地位指數表) 및 지위지수곡선(地位指數曲線)을 작성(作成)하고, 이를 비교(比較)하여 보면 지위지수급(地位指數級) 6-18에서는 낙엽송이 잣나무보다 높게 추정(推定)되고, 지위지수급(地位指數級) 20에서는 잣나무가 낙엽송보다 다소 높게 추정(推定)되었다.

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