Distribution of the Tax Burden across Companies in Vietnam: The Issue of Corporate Tax Avoidance

Kien Trung TRAN(Kien Trung TRAN ) 한국유통과학회 2023 유통과학연구 Vol.21 No.6

Fabrication of a standalone MEA shell using silver nanowire

Nguyen Trung Hai(Hai Trung Nguyen),Ki Ju Kang(강기주) 대한기계학회 2019 대한기계학회 춘추학술대회 Vol.2019 No.4

무선 Ad-Hoc 네트워크를 위한 흐름 기반의 Media Access Control (F-MAC)

Tran Minh Trung(Tran Minh Trung),모정훈(Jeonghoon Mo),김성륜(Seong-Lyun Kim),곽재욱(Jaewook Kwak) 한국정보과학회 2004 한국정보과학회 학술발표논문집 Vol.31 No.2Ⅲ

본 논문에서 우리는 무선 ad-hoc 네트워크에서의 효율성과 공명성 문제[2]를 해결하기 위해 기존의 802.11 MAC에서 단순한 개선으로 효율적인 결과를 얻을 수 있는 새로운 방식을 제안한다. 우리의 제안된 방식은 흐름 개념을 기반으로 하고 있다. 릴레이를 해야 하는 프레임을 가지고 있는 노드들에게 다른 노드들 보다 높은 우선순위를 할당하여 빠른 중단간의 전달함으로써 높은 성능향상을 기대할 수 있다. 또한 패킷을 전달한 후 노드는 낮은 우선순위를 갖게 되고 다른 노드에게 양보를 하여 노드들이 서로간에 공평하게 대역폭을 받을 수 있게 한다. 기존의 방식에 비해 두 배 가량 향상된 전송량과 비교적 공평하게 할당된 대역폭을 보여주는 시뮬레이션의 결과는 우리의 주장을 뒷받침해준다.

Compliance of education journals in Vietnam with the minimum criteria to be indexed in the ASEAN Citation Index and Scopus

Trung Tran,Loc Thi My Nguyen,Thanh Thi Nghiem,Hien Thi Thu Le,Cuong Huu Nguyen,Thuy Phuong La,Trung Tien Nguyen,Hang Thi-Thu Nguyen 한국과학학술지편집인협의회 2019 Science Editing Vol.6 No.2

This study aimed at elucidating the present situation of scholarly journals published in Vietnam according to the minimum criteria to be indexed in the ASEAN Citation Index (ACI) and Scopus, with the goal of suggesting development strategies for scholarly journals in Vietnam. From the 387 journals accredited by the Vietnamese State Council for Professorship, 13 education journals were arbitrarily selected, and their compliance with the five minimum criteria for the ACI (peer review, timeliness, abstracts in English, references in Roman script, and a website in English) and the six minimum criteria for Scopus (peer review, timeline, abstracts in English, references in Roman characters, Electronic International Standard Serial Number [ISSN], and publication ethics) were assessed. Two of the 13 journals were eligible to be indexed in the ACI, while none fulfilled the minimum criteria to be indexed in Scopus. An urgent task for the editors of those journals is to establish an informative journal homepage in English that provides basic information on the journal. Then, an Electronic ISSN can be obtained from the ISSN International Center. Furthermore, the following steps are suggested for journal promotion: establishment of appropriate editorial policies and publication ethics procedures, improvement of research integrity, enhancement of the journals’ reputation in the international scientific community, and improvement of the online publishing system by adopting a journal manuscript management system. To achieve those goals, financial support from the Vietnamese government will be invaluable.

Identification of In-Home Appliance Types Based on Analysis of Current Consumption Using Energy Metering Circuit

Tin Trung Tran,Trung Xuan Pham,김종욱 대한임베디드공학회 2017 대한임베디드공학회논문지 Vol.12 No.2

One of the important applications of activity sensing in the home is energy monitoring. Many previous methodologies for detecting and recognizing household appliances have been proposed. This paper presents an approach that uses an energy metering circuit (EMC) to classify and identify the various electrical devices in home based on root-mean-square (RMS) consumed current value. EMC gathers the RMS current values created by appliance state transition (e.g., on to off) and apparatus operating process. In this paper, an identification algorithm is proposed to detect a change in current levels using the standard deviation of current signals and their average values. In addition, characteristic of the appliance is extracted concerning four feature parameters concerning the number of current levels, the minimum level, the maximum level, and signal-to-noise ratio (SNR) of them. Experiment results validate the reliable performance of the proposed identification method for 11 representative appliances.

Measurement of Current Magnitude for Home Appliances using Smart E-Meter

Tran Trung-Tin(트란 트렁 틴),Pham Xuan-Trung(팜 수안 트렁),Ngo Minh-Tri(능오 밍 트리),Jong-Wook Kim(김종욱) 한국정보기술학회 2015 Proceedings of KIIT Conference Vol.2015 No.6

본 논문은 Smart E-Meter를 이용해서 방안에 있는 가전제품의 전류 값을 관찰하고 측정하는 것이 가능한 데이터측정(DAQ) 시스템을 제안한다. 제안된 DAQ 시스템은 Smart E-Meter 장치를 사용하고 소프트웨어는 LabVIEW의 VISA 함수를 사용해서 설계되었다. 그리고 제안된 시스템으로 각 전자제품의 전류 변화를 데이터 파일로 만들 수 있으며, 최신 전류 데이터에 창을 씌워 전류의 이동평균과 이동표준편차를 계산함으로써 현재 연결되어 있는 가전제품이 가동 시작, 정상 운용, 모드 변화 중 어느 단계인지를 판단하게 할 수 있다. 제안된 시스템은 Smart E-Meter 시제품을 이용해서 실현 가능성을 검증받는다. This paper proposes a data acquisition (DAQ) system to observe and monitor the magnitude value of current signal for in-home appliances in a room based on Smart E-Meter. The DAQ system included DAQ device with Smart E-Meter and DAQ software designed by LabVIEW with the VISA function. In addition, this analysis tool produces the current profile of each electric appliances. Based on the profile, the moving average and moving standard deviation values are utilized to evaluate the current magnitude by sliding a window for most recent data. Specifically, consideration of the difference in current magnitude allows to determine the status of the connected appliances which are starting-up, working or adjusting operation mode. The proposed approach is validated through operating experiment with the prototype of Smart E-Meter.

Identification of In-Home Appliance Types Based on Analysis of Current Consumption Using Energy Metering Circuit

Tran, Tin Trung,Pham, Trung Xuan,Kim, Jong-Wook Institute of Embedded Engineering of Korea 2017 대한임베디드공학회논문지 Vol.12 No.2

One of the important applications of activity sensing in the home is energy monitoring. Many previous methodologies for detecting and recognizing household appliances have been proposed. This paper presents an approach that uses an energy metering circuit (EMC) to classify and identify the various electrical devices in home based on root-mean-square (RMS) consumed current value. EMC gathers the RMS current values created by appliance state transition (e.g., on to off) and apparatus operating process. In this paper, an identification algorithm is proposed to detect a change in current levels using the standard deviation of current signals and their average values. In addition, characteristic of the appliance is extracted concerning four feature parameters concerning the number of current levels, the minimum level, the maximum level, and signal-to-noise ratio (SNR) of them. Experiment results validate the reliable performance of the proposed identification method for 11 representative appliances.

Evaluating the Cryoprotective Encapsulation of the Lactic Acid Bacteria in Simulated Gastrointestinal Conditions

Trung Hau Nguyen,YongGyeong Kim,Jin-Sung Kim,Yulah Jeong,Hye Min Park,Jin Woo Kim,Ji-Eun Kim,Hyemin Kim,Nam-Soo Paek,강창호 한국생물공학회 2020 Biotechnology and Bioprocess Engineering Vol.25 No.2

To expect the positive physiological functions from probiotic consumption, the lactic acid bacteria should survive, partially, in the gastrointestinal (GI) tract. This study aimed to evaluate the viable stability of probiotic bacterial cells (Lactobacillus plantarum MG989, L. fermentum MG901, Streptococcus thermophilus MG5140, Lactococcus lactis MG5125, and Enterococcus faecium MG89-2) that were coated with sodium alginate and pumpkin powder (SP) by comparing their resistance in simulated intestinal fluid (with pancreatin) and simulated gastric fluid (with pepsin) in vitro with that of the non-coated free cells. The viable stability was determined by counting cells with colony forming unit (CFU) from agar plate culture of SP coated and non-coated free cells in simulated GI conditions. Survival rate enhanced up to 28.7% and 14.0% in the condition of simulated gastric fluid and simulated intestinal fluid, respectively. The results showed that the SP coated cells exhibited considerably greater resistance to the simulated gastric fluid than the activated cells (p < 0.001), showing that the SP coating may enhance the survival of probiotic bacteria after consumption during their transit through the GI tract after freeze-drying process.

A Study about Output Filter of Paralleled Three-Phase Grid-Connected PV Inverters

Trung-Kien Vu 전력전자학회 2011 전력전자학술대회 논문집 Vol.2011 No.7

The rising popularity of renewable energy sources resulted in development of the units of higher rated powers. As a result of the limited power handling capacity of individual devices, paralleling is the choice to increase the equipment rating, while keeping the THD of the current at the PCC within the agency specified standards. And their typical power circuit configuration limits the stress on individual devices to an appreciable extent. The main scope of this paper is the analysis of filter structure in paralleling inverter system’s operation. Simulation results are shown to verify the theoretical analysis.

PR Controller Based Current Control Scheme for Single-Phase Inter-Connected PV Inverter

Trung-Kien Vu(부우충기엔),Se-Jin Seong(성세진) 한국산학기술학회 2009 한국산학기술학회논문지 Vol.10 No.12

최근 태양광 시스템에서는 기존의 태양광 시스템을 계통과 전원으로 상호 접속하는 것에 대한 연구에 관심 이 모아지고 있다. 단상, 삼상 시스템에 관계없이 태양광 시스템에서 태양광 인버터는 계통연계 동작에 중요한 역할 을 하기 때문에 전체 시스템에서 핵심요소로 고려된다. 태양광 인버터를 제어하기 위해서는 부하 전류 조절이 핵심요 소 중 하나이다. 일반적으로 태양광 인버터에서 이용되는 PI 제어기는 정상상태 오차와 왜란에 취약하다는 단점을 가 지고 있기 때문에 실제 시스템에 완벽하게 적용하기에는 무리가 있다. 특히, 이는 고주파영역에서의 PI와 PR 제어기 의 성능을 비교해보면 알 수 있다. 이 논문에서 제시된 PR 제어기는 무한 이득을 교류 기본파 성분에 넣을 수 있기 때문에 PR 제어기는 회전좌표계의 PI 제어기에서 사용되는 디커플링 기법과 복잡한 변환 없이 제로 정상상태오차에 도달할 수 있다. 그렇기 때문에 이 논문에서는 PI 제어기를 대체하는 이론적 분석을 통해 PR 제어기를 설계하였다. 논문에 제시되어 있는 이론을 바탕으로 한 PR 제어기를 고정 소수점 연산방식의 32비트 마이크로컨트롤러 DSP320F2812를 기반으로 한 3kW 프로토타입 태양광 인버터에 적용, 평가하였다. 또한 태양광 인버터의 제어 성능을 시뮬레이션과 실험결과를 통하여 보여주고 검증하였다. Nowadays, the PV systems have been focused on the interconnection between the power source and the grid. The PV inverter, either single-phase or three-phase, can be considered as the core of the whole system because of an important role in the grid-interconnecting operation. An important issue in the inverter control is the load current regulation. In the literature, the Proportional+Integral (PI) controller, normally used in the current-controlled Voltage Source Inverter (VSI), cannot be a satisfactory controller for an ac system because of the steady-sate error and the poor disturbance rejection, especially in high-frequency range. By comparison with the PI controller, the Proportional+Resonant (PR) controller can introduce an infinite gain at the fundamental ac frequency; hence can achieve the zero steady-state error without requiring the complex transformation and the dq-coupling technique. In this paper, a PR controller is designed and adopted for replacing the PI controller. Based on the theoretical analyses, the PR controller based control strategy is implemented in a 32-bit fixed-point TMS320F2812 DSP and evaluated in a 3kW experimental prototype Photovoltaic (PV) power conditioning system (PCS). Simulation and experimental results are shown to verify the performance of implemented control scheme in PV PCS.