• 한국통신학회논문지
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• 제27권1C호
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• pp.84-89
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• 2002

제출된 논문에서는 고음질의 오디오 신호를 전송하는 무선 모뎀의 수신부에서 TCM 복호와에 사용되는 Viterbi 디코더를 VHDL을 이용하여 설계하고 FPGA를 이용하여 구현하였다. 이 논문에서는 TCM 부호화와 복호화와 복호화 과정을 간단히 설명한 후 부호화기와 복호화기를 FPGA로 구현한 다음 PC 상에서 채널의 영향을 재현하여 신호 대잡음비($E_b/N_0$) 변화에 따른 시스템의 비트에러율 성능을 제시하고 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1549-1551
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• 2002

현재 게이트 길이가 100nm 이하의 MOSFET 소자를 구현할 때 가장 대두되는 문제인 short channel effect를 억제하는 방법으로 제안된 소자 중 하나가 double gate (DG) silicon-on-insulator (SOI) MOSFET이다. 그러나 DG SOI MOSFET는 두 게이트간의 align과 threshold voltage control 문제가 있다. 본 논문에서는 DG SOI MOSFET에서 이상적으로 게이트가 align된 구조와 back 게이트가 front 게이트보다 긴 non-align된 구조가 subthreshold 동작 영역에서 impact ionization에 미치는 영향에 대해 시뮬레이션을 통하여 비교 분석하였다. 그 결과 게이트가 이상적으로 align된 구조보다 back 게이트가 front 게이트보다 긴 non-align된 구조가 게이트와 드레인이 overlap된 영역에서 impact ionization이 증가하였으며 게이트가 각각 n+ 폴리실리콘과 p+ 폴리실리콘을 가진 소자에서 두 게이트가 같은 work function을 가진 소자보다 높은 impact generation rate을 가짐을 알 수 있었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1819-1824
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• 2004

The common method to improve heat transfer in Nuclear fuel rod bundle is install a mixing vane in space grid. The previous split mixing vane is guides cooling water to swirl flow in sub-channel of fuel assembly. But, this swirl flow decade rapidly after mixing vane and the effect of enhancing the heat transfer vanish behind this short region. The large scale secondary vortex flow was generated by rearranging the inclined angle direction of mixing vanes to the coordinated directions. This LSVF mixing vanes generate the most strong secondary flow vortices which maintain about 35 $D_H$ after the spacer grid and the streamwise vorticity in subchannel with LSVF mixing vane sustain two times more than that in subchannel with split mixing vane. The turbulent kinetic energy and the Reynolds stresses generated by the mixing vanes have nearly same scales but maintain twice more than previous type.

• JSTS:Journal of Semiconductor Technology and Science
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• 제10권1호
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• pp.20-27
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• 2010

Modeling is essential to simulate the operation of integrated circuit (IC) before its fabrication. Seeing a large number of Metal-Oxide-Silicon Field-Effect-Transistor (MOSFET) models available, it has become important to understand them and compare them for their pros and cons. The task becomes equally difficult when the complexity of these models becomes very high. The paper reviews the mainstream models with their physical relevance and their comparisons. Major short-channel and quantum effects in the models are outlined. Emphasis is set upon the latest compact models like BSIM, MOS Models 9/11, EKV, SP etc.

• Journal of Electrical Engineering and Technology
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• 제9권2호
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• pp.655-661
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• 2014

In this paper, a new two dimensional (2D) analytical modeling and simulation for a surrounding gate tunnel field effect transistor (TFET) is proposed. The Parabolic approximation technique is used to solve the 2-D Poisson equation with suitable boundary conditions and analytical expressions for surface potential and electric field are derived. This electric field distribution is further used to calculate the tunneling generation rate and thus we numerically extract the tunneling current. The results show a significant improvement in on-current characteristics while short channel effects are greatly reduced. Effectiveness of the proposed model has been confirmed by comparing the analytical results with the TCAD simulation results.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.167-168
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• 2007

Design Rule이 작아짐에 따라 Transistor performance 향상을 위한 여러 방안중 SEG 공정이 적용되고 있으며 이에 따른 Transistor 특성 연구 결과이다. SEG공정 적용시 SEG Profile에 따라 Transistor의 Short Channel Effect 열화가 발생하였고 그 원인은 Sidewall Facet발생으로 추정되며 이를 개선시 Tr 특성이 개선됨을 확인하였다.

• 설비공학논문집
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• 제18권10호
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• pp.811-818
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• 2006

Mixing vanes have been installed in the space grid of nuclear fuel rod bundle to improve turbulent heat transfer. Split mixing vanes induce the vortex flow in the cooling water to swirl in sub-channel of fuel assembly. But, The swirling flow decays rapidly so that the heat transfer enhancing effect limited to short length after the mixing vane. In the present study, the large scale vortex flow (LSVF) is generated by rearranging the mixing vanes to the coordinated directions. This LSVF mixing vanes generate the most strong secondary flow vortices which maintain about $35D_h$ after the spacer grid. The streamwise vorticity generated by LSVF sustain two times more than that split mixing vane.

• ETRI Journal
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• 제44권3호
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• pp.491-503
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• 2022

Metal-oxide-semiconductor field-effect transistors (MOSFETs) are continuously scaling down in the nanoscale region to improve the functionality of integrated circuits. The scaling down of MOSFET devices causes short-channel effects in the nanoscale region. In nanoscale region, leakage current components are increasing, resulting in substantial power dissipation. Very large-scale integration designers are constantly exploring different effective methods of mitigating the power dissipation. In this study, a transistor-level input-controlled stacking (ICS) approach is proposed for minimizing significant power dissipation. A low-power ICS approach is extensively discussed to verify its importance in low-power applications. Circuit reliability is monitored for process and voltage and temperature variations. The ICS approach is designed and simulated using Cadence's tools and compared with existing low-power and high-speed techniques at a 22-nm technology node. The ICS approach decreases power dissipation by 84.95% at a cost of 5.89 times increase in propagation delay, and improves energy dissipation reliability by 82.54% compared with conventional circuit for a ring oscillator comprising 5-inverters.

• 유통과학연구
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• 제15권1호
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• pp.105-114
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• 2017

Purpose - Recently, domestic pharmaceutical market is growing steadily, but top-tier companies are concentrating on sales growth. In this market, SMEs, which account for more than 80% of the entire market, suffer from the problem of lower margins and increasing inventory costs. According to the government's policy changes related to pharmaceuticals, it is pointed out that the management of existing customers and the control of salespeople are important issues for pharmaceutical companies. This study investigates the effect of the control system on the salesperson in domestic pharmaceutical distribution channel on customer-oriented selling behaviors and sales performance. Research design, data, and methodology - To verify the proposed research model and test hypotheses, the authors selected 244 MR(medical representatives)'s responses which have currently relationship with doctors or pharmacists. This study carefully investigated the reliability, content validity, convergent validity, and discriminant validity of the proposed model. Results - The authors find out the following results: capacity control, activity control, and self control have positive effects on customer-oriented selling behaviors and customer-oriented selling behaviors have a positive effect on sales performance. In addition, we present alternative model to check the direct effect between the control systems and the sales performance, but control system factors except self control have no direct influence. Conclusions - First of all, competency control and activity control increases the customer-oriented selling behavior of the salesperson. This means that the salesperson's sales skill, negotiation skill, customer access skill, presentation ability, monitoring, direction and evaluation are important and it is also important to control activities to check the number of visits to customers, report preparation, and customer service etiquette. Second, the fact that self-control of salesperson affects the customer-oriented selling behavior suggests that self-control is not controlled by external factors but rather establishes short/long-term goals. Therefore, it is important for sales organization to create an environment in which members can induce persistent incentives for self-control. Finally, output control did not affect customer-oriented sales behavior, which is less likely to form confidence or motivation to MRs when output control is perceived as a means of monitoring, supervising, or controlling rather than providing information to salespeople.

• JSTS:Journal of Semiconductor Technology and Science
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• 제14권5호
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• pp.615-624
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• 2014

In this paper, we explore the electrical properties and high-frequency performance of carbon nanotube field-effect transistors (CNTFETs), based on the non-equilibrium Green's functions (NEGF) solved self - consistently with Poisson's equations. The calculated results show that CNTFETs exhibit superior performance compared with graphene nanoribbon field-effect transistors (GNRFETs), such as better control ability of the gate on the channel, higher drive current with lower subthreshold leakage current, and lower subthreshold-swing (SS). Due to larger band-structure-limited velocity in CNTFETs, ballistic CNTFETs present better high-frequency performance limit than that of Si MOSFETs. The parameter effects of CNTFETs are also investigated. In addition, to enhance the immunity against short - channel effects (SCE), hetero - material - gate CNTFETs (HMG-CNTFETs) have been proposed, and we present a detailed numerical simulation to analyze the performances of scaling down, and conclude that HMG-CNTFETs can meet the ITRS'10 requirements better than CNTs.