• 제목, 요약, 키워드: TRA

검색결과 216건 처리시간 0.039초

바이폴라 트랜스레지스턴스 증폭기 설계 (A Design of Bipolar Transresistance Amplifiers)

  • 차형우;임동빈;송창훈
    • 대한전자공학회논문지SD
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    • v.38 no.11
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    • pp.828-835
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    • 2001
  • 고정도 전류-모드 신호 처리를 위한 새로운 바이폴라 트랜스레지스턴스 증폭기(TRA)와 이것의 오프셋 보상된 TRA를 제안하였다. 두 TRA는 전류 입력을 위한 두 개의 전류 폴로워, 전류차를 얻기 위한 전류 가산기, 전류를 전압으로 변환시키기 위한 저항, 그리고 전압 출력을 위한 전압 폴로워로 구성되었다. 오프셋 보상된 TRA는 TRA의 오프셋 전압을 감소시키기 위한 다이오드 결선된 npn과 pnp 트랜지스터를 채용하였다. 시뮬레이션 결과, TRA근 입-출력 단자에서 0.5 Ω의 임피던스와 40 mV의 오프셋 전압을 갖고 있다는 것이 확인되었다. 오프셋 보상된 TRA는 1.1 mV의 오프셋 전압과 0.25 Ω의 임피던스를 갖고 있다. 두 개의 TRA를 단위-이득의 트랜스레지스턴스를 갖는 전류-전압 변환기로 이용할 때 3-dB 차단 주파수는 40 MHz이다. 제안한 두 TRA의 전력 소비는 11.25 mW이다.

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Factors Influencing Family Business Decision for Borrowing Credit from Commercial Banks: Evidence in Tra Vinh Province, Viet Nam

  • NGUYEN, Ha Hong;LIEN, Trinh To
    • The Journal of Asian Finance, Economics, and Business
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    • v.6 no.2
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    • pp.119-122
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    • 2019
  • The study aims to investigate factors influencing business households' decision for borrowing credit: the case of commercial banks in Tra Vinh Province, VietNam. The study was conducted by collecting data from 300 business households traded at four commercial banks in Tra Vinh province (Viet Nam bank for agriculture and rural development, Tra Vinh Branch; Viet Nam jointstock commercial bank industry and trade, Tra Vinh Branch; Asia joinstock commercial bank, Tra Vinh Branch; Viet Nam jointstock commercial bank for foreign trade, Tra Vinh Branch). By the use of the Binary Logistic regression method, the research found out that the factors influencing to borrow c redit of household business's decision including: banks brand names, loan interest rates, service attitude, and loan procedures. Of those, the banks brand names and lending interest rates have the strongest impacts on borrow credit decision of business households at commerc ials banks in Tra Vinh province. Since then, the study has proposed solutions to improve access to credit of business households in commercial banks in Tra Vinh province in the coming time, such as: developing a bank brand; the development of flexible lending interest rate policies; improve service style of bank staff; at the same time, simplifying lending procedures.

Factors Affecting Employee Loyalty: A Case of Small and Medium Enterprises in Tra Vinh Province, Viet Nam

  • NGUYEN, Ha Hong;NGUYEN, Trung Thanh;NGUYEN, Phong Thanh
    • The Journal of Asian Finance, Economics, and Business
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    • v.7 no.1
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    • pp.153-158
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    • 2020
  • The study aims to identify the factors affecting employee loyalty in the case of small and medium enterprises (SMEs) in Tra Vinh province, Viet Nam and to find out critical factors affecting the loyalty of employees in SMEs. This is implemented with the method of collecting primary data of 320 employees working at SMEs in 5 districts including: Cau Ngang, Tra Cu, Chau Thanh, Cang Long, Tieu Can) and Tra Vinh City, Viet Nam. Using the multivariate regression method, the researchers have found 6 factors affecting employee loyalty: colleagues, leaders, job characteristics, remuneration policies, organizational culture, and working environment. Particularly, learning opportunities may not be not statistically significant for employees' loyalty towards small and medium-sized enterprises in Tra Vinh province. From the above research results, the authors have proposed implicational piolicies such as: focusing on colleague relationships, improving leadership of business owners, attaching importance to appropriate work arrangement, having appropriate remuneration policies for laborers, building effective organizational culture and working environment to improve employee loyalty at SMEs. From the above policy implications, helping business owners realize the aspirations of workers in small and medium-sized enterprises more closely in the future, in order to sustainably develop the business system in Vietnam.

Evaluation of the Genetic Diversities and the Nutritional Values of the Tra (Pangasius hypophthalmus) and the Basa (Pangasius bocourti) Catfish Cultivated in the Mekong River Delta of Vietnam

  • Men, L.T.;Thanh, V.C.;Hirata, Y.;Yamasaki, S.
    • 아세아태평양축산학회지
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    • v.18 no.5
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    • pp.671-676
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    • 2005
  • A total of 50 individual catfish, the Tra (Pangasius hypophthalmus) cultivated in either floating cages (Tra-c) or in ponds (Tra-p) and the Basa (Pangasius bocourti) raised in three floating cages, were collected in two of the Mekong Delta provinces. The caudal fin of each individual fish was used for protein electrophoresis employing the SDS-PAGE method. The one fillet sides were used as a representative sample to determine the dry matter (DM), crude protein (CP), ether extract (EE) and amino acids (AAs). The catfish oil was extracted from the belly fats, and the fatty acid (FA) composition was analyzed. There were 21 bands of the Tra and the Basa. Protein bands of the two varieties were 28.6-33.3% polymorphic, while polymorphic individuals of the Tra ranged from 80.0 to 100.0%, and the Basa was 90.0% polymorphic. The phenotypic diversity (Ho) of the Tra ranged from 1.71 to 1.80, while the Basa ranged as high as 2.14%. Diversity values (H$_{EP}$) for genetic diversity markers were equal in the Tra and the Basa. The sum of the effective number of alleles (SENA) of both varieties ranged from 3.40 to 3.83 for the Basa and the Tra, respectively. The lower values of Ho and SENA, as compared with those of the fresh water prawn (Macrobrachium equidens) in the area, would suggest that the species with the low values will become extinct due to inbreeding; the gene pools of each observed population were below a suitable threshold. Many of the differences in the nutritional values of the Tra-c, the Tra-p and the Basa were measured; their nutrient values were comparable to fishmeal or fish oil. Most of the DM, CP, and EE were higher in the Tra, especially in the Tra-c. The essential AA content, especially that of lysine, was highest in the Tra-c, next highest in the Tra-p, and lowest in the Basa. Therefore, the amino acid patterns were closer to the ideal patterns in the same sequences. In contrast, the essential FAs were concentrated in the Basa fish oil. It was found that suitable selection of parents for seed production is required to avoid inbreeding. Catfish may be valuable sources of nutrition for both humans and animals, and the differences in their nutritional values by variety and/or management must be taken into account.

차등 서비스 네트워크의 확신 서비스에서 공평성 향상을 위한 3색 마킹 메커니즘 (A Three-Color Marking Mechanism for Fairness Improvement in the Assured Service of the Diffserv Network)

  • 모상덕;정광수
    • 한국정보과학회논문지:정보통신
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    • v.30 no.6
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    • pp.764-775
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    • 2003
  • 차등 서비스 네트워크(Diffserv network)의 확신 서비스(Assured Service)에 대한 기존 연구는 TCP 플로우의 RTT(Round Trip Time) 및 계약한 목표 전송률(CTR: Committed Target Rate)에 따른 전송률 분배의 공평성에 대한 고려가 부족하다. 본 논문에서는 기존 연구에서의 문제점들을 개선한 TRA3CM(Target rate and RTT Aware 3 Color Marker) 메커니즘을 제안한다. TRA3CM에서는 평균 전송률을 예측하기 위한 시간 창 길이로 RTT를 이용하며, 3색 마킹을 제공하고, RTT와 목표 전송률을 동시 고려하여 집합 플로우들 사이에 공평하게 전송률을 분배할 수 있다. 또한 under-provisioned 네트워크에서도 RTT의 영향을 완화시켜 집합 플로우들 사이에 공평성을 보장하고 있다. 기존 방식들과 비교한 결과 제안한 TRA3CM은 RTT의 영향을 완화시키는 데 있어 좋은 성능을 보이며, 목표 전송률에 비례하는 전송률 제공에서도 우수한 성능을 확인할 수 있었다.

지구성 운동시 옻나무 추출액의 지질과산화 및 염증성사이토카인 억제효과 (Inhibitory Effect of Rhus Verniciflua Extract on Lipid Peroxidation and Inflammatory Cytokines during Endurance Exercise Training)

  • 이윤경;권오선;송영주;김세현;김판기;류승필
    • 한국산림과학회지
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    • v.99 no.1
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    • pp.102-110
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    • 2010
  • 옻나무 추출액을 섭취하며 운동훈련을 부하하였을 때 항산화기능 및 염증성사이토카인의 차이에 대하여 연구하고자 하였다. 이를 위하여 Sprague-Dawley(SD)계 수컷 쥐를 대상으로 SED(안정군), TRA(운동훈련군), RVE(옻나무 추출액 섭취군), 그리고 RVE-TRA(옻나무 추출액 섭취와 운동 병행군)으로 구분하였다. TRA와 RVE-TRA는 점증적부하법을 이용한 트레드밀 훈련을 실시하였으며, RVE와 RVE-TRA에게는 10 mL/kg의 옻나무 추출액을 경구투여 하였다. 항산화기능을 분석하기 위하여 혈중 superoxide dismutase(SOD), glutathione peroxidase(GSH-Px), malondialdehyde(MDA)를 분석하였으며, 염증성사이토카인의 변화분석을 위하여 interleukin-6(IL-6), tumor necrosis factor-alpha(TNF-${\alpha}$), C-reactive protein(CRP), nitric oxide(NO)를 분석하였다. SOD는 RVE-TRA가 다른 집단에 비하여 가장 높았으며, TRA가 SED와 RVE에 비하여 유의하게 높았다. GSH-Px는 SED가 다른 집단에 비하여 유의하게 낮았다. MDA는 SED에 비하여 다른 집단에서 모두 유의하게 낮았다. IL-6와 TNF-${\alpha}$는 RVE와 RVE-TRA가 다른 두 집단에 비하여 낮았다. 또한 CRP는 SED가 다른 집단에 비하여 가장 낮았다. NO는 SED와 TRA가 다른 두 집단에 비하여 높았다. 이러한 결과를 볼 때, 운동시옻나무 추출액의 섭취는 지질과산화를 억제시키고 항염증성 반응을 유발하여 운동시 발생가능한 부작용을 억제할 수 있는 결과를 보였다. 이점을 고려하여 옻추출물이 가지고 있는 특성을 최대한 활용하여 다양한 방법으로 접근한다면 우리나라 전역에 걸쳐 자생하고 있는 옻나무의 활용도를 증대시킬 수 있으리라 생각된다.

공정 범주에 따른 ECETOC TRA 모델 평가로부터 도출한 한국 작업장 노출 평가 개선 방안 (Enhancement of Occupational Exposure Assessment in Korea through the Evaluation of ECETOC TRA according to PROCs)

  • 김기은;김종운;전현표;김상헌;정연승
    • 한국환경보건학회지
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    • v.45 no.2
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    • pp.173-185
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    • 2019
  • Objectives: The objectives of this study are to evaluate the accuracy and precision of exposure model ECETOC TRA v.3.1 by comparing model predictions with repeated exposure measurements in Korean workplaces and to investigate the applicability of ECETOC TRA to Korean workplace exposure assessment in K-REACH. Methods: Measured values and work conditions for 14 kinds of chemicals collected from exposure field surveys conducted at 10 companies in Korea were utilized for this study. All possible process categories (PROCs) considered to be relevant to each work process classification were selected and applied to ECETOC TRA as major determining parameters. In order to quantify the accuracy of the model, the lack of agreement (bias, relative bias, precision) was calculated and the risk ratios for each exposure situation between estimated and measured were also compared. Results: The estimated values varied between five and 25 times according to the PROCs for all exposure situations (ESs) based on tasks/chemicals. The results showed that most of the estimated values were below the measured values, and just 13 of 53 tasks were above the measured values. The overall bias and precision were $-2.91{\pm}1.62$ with ECETOC TRA, and we found that ECETOC TRA showed a low level of conservatism when applied to Korean workplaces, similar to previous studies. Conclusions: This study demonstrates that the existed PROC codes have limitations in fully covering various ESs in Korea. In order to improve the applicability of ECETOC TRA in K-REACH, the addition of new PROCs for Korean industries are necessary.

Biodiesel Production From Fat of Tra Catfish and Basa Catfish (Viet Nam) Using Alkaline Catalysts

  • Huong, Le Thi Thanh;Tan, Phan Minh;Hoa, Tran Thi Viet;Lee, Soo
    • 한국응용과학기술학회지
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    • v.25 no.3
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    • pp.299-312
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    • 2008
  • The fat of Tra and Basa catfish (Mekong Delta, Viet Nam) was evaluated for the first time as the potential feedstock for biodiesel production, due to its abundance, availability and cheap cost. The unsaturated fatty acid contents of Tra and Basa fat were 57.97% and 64.17%, respectively. Biodiesel was prepared from Tra and Basa fat by methanolysis reaction using alkali catalysts like sodium hydroxide and potassium hydroxide. Effects of various process parameters on biodiesel production, such as molar ratio of methanol to fat, catalyst concentration, temperature and time were investigated. As those results, the transesterification can be performed under moderate conditions, and the biodiesel yields were shown more than 90%. KOH catalyst was the best catalyst for biodiesel production from both Basa and Tra fat. As the feedstock aspect, Basa fat was indicated more efficiency than that of Tra fat. The maximum yield could be achieved by the transesterification from Basa fat with 5:1 molar ratio of methanol to fat, 0.8% KOH catalyst, $50^{\circ}C$, and 50 min. For Tra fat, the optimal condition were at 6:1 molar ratio of methanol to fat, 0.8% KOH catalyst, $50^{\circ}C$, and 45 min. Nowadays, due to cheaper cost and abundance, Tra fat is a promised resource for cheap biodiesel production in Viet Nam.

차등 서비스 네트워크에서 AF 서비스의 공평성 향상 기법 (A Mechanism to Improve the Fairness of the AF Service in Diffserv Network)

  • 모상덕;정광수
    • 한국정보과학회논문지:정보통신
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    • v.31 no.5
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    • pp.469-481
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    • 2004
  • 차등 서비스 네트워크(Diffserv network)의 AF 서비스(Assured Forwarding Service)에 대한 기존 연구는 RTT(Round Trip Time), 목표 전송률(CTR: Committed Target Rate), TCP에 대한 UDP의 영향에 따른 전송률 분배의 공평성에 대한 고려가 부족하다. 본 논문에서는 기존 연구에서의 문제점들을 개선한 TRA3CM(Target rate and RTT Aware 3 Color Marker) 기법 및 TRBD(Target Rate Based Dropping) 기법을 이용하는 FDSA(Fair Differentiated Service Architecture) 구조를 제안한다. TRA3CM 및 TRBD 기법은 RTT, 목표 전송률, UDP 플로우 등을 고려한 마킹 및 패킷 폐기 기능을 제공하여 집합 플로우들 사이에 공평하게 전송률을 분배할 수 있다. ns 시뮬레이터를 이용하여 기존 방식들과 비교한 결과 제안한 TRA3CM 및 TRBD 기법은 RTT, 목표 전송률 및 UDP를 고려한 공평한 대역분배 기능이 기존 방식에 비해 우수함을 확인할 수 있었다.

Purification and Characterization of a New Galactoside Specific Lectin from Trichosanthes kirilowii Root

  • Yun, Doo-Hee;Park, Eun-Ju;Park, Jong-Ok;Lee, Young-Han;Seo, Jeong-Kon;Ryu, Sung-Ho;Suh, Pann-Ghill;Kim, Hee-Sook
    • BMB Reports
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    • v.28 no.1
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    • pp.6-11
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    • 1995
  • A new lectin, named TRA, was purified from Trichosanthes kirilowii root by acid-treated Sepharose 6B, Mono-Q, and TSK-gel 3000SW column sequential chromatography. The lectin appeared homogeneous by native gel electrophoresis at pH 4.3 and gave two protein bands of Mr=31 and 28 kDa by SDS-PAGE. The N-terminal amino acid sequences of the polypeptides of TRA have not been reported in amino acid sequences of the lectins. TRA lectin formed a precipitate with asialofetuin, neuraminidase-treated fetuin. A sugar inhibition assay indicated that N-acetyl-D-galactosamine, among the monosaccharides tested, was the most potent inhibitor of TRA-induced hemagglutination. Asialofetuin showed a 260-times stronger inhibitory activity than N-acetyl-D-galactosamine. TRA lectin also showed agglutination with normal leukocytes and lymphoma cells, but not with premature hemopoietic cells. These results suggest that TRA is a novel plant lectin.

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