• Journal of Multimedia Information System
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• 제8권1호
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• pp.31-34
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• 2021

The classical HMM is defined by a parameter triple �� = (��, A, B), where each parameter represents a collection of probability distributions: initial state, state transition and output distributions in order. This paper proposes a new stationary parameter e = (e1, e2, …, eN) where N is the number of states and et = P(|xt = i, y) for describing how an input pattern y ends in state xt = i at time t followed by nothing. It is often said that all is well that ends well. We argue here that all should end well. The paper sets the framework for the theory and presents an efficient inference and training algorithms based on dynamic programming and expectation-maximization. The proposed model is applicable to analyzing any sequential data with two or more finite segmental patterns are concatenated, each forming a context to its neighbors. Experiments on online Hangul handwriting characters have proven the effect of the proposed augmentation in terms of highly intuitive segmentation as well as recognition performance and 13.2% error rate reduction.

• 인터넷정보학회논문지
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• 제22권6호
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• pp.1-8
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• 2021

With the rapid growth of intelligent devices and communication technologies, 5G network environment has become more heterogeneous and complex in terms of service management and orchestration. 5G architecture requires supportive technologies to handle the existing challenges for improving the Quality of Service (QoS) and the Quality of Experience (QoE) performances. Among many challenges, traffic steering is one of the key elements which requires critically developing an optimal solution for smart guidance, control, and reliable system. Mobile edge computing (MEC), software-defined networking (SDN), network functions virtualization (NFV), and deep learning (DL) play essential roles to complementary develop a flexible computation and extensible flow rules management in this potential aspect. In this proposed system, an accurate flow recommendation, a centralized control, and a reliable distributed connectivity based on the inspection of packet condition are provided. With the system deployment, the packet is classified separately and recommended to request from the optimal destination with matched preferences and conditions. To evaluate the proposed scheme outperformance, a network simulator software was used to conduct and capture the end-to-end QoS performance metrics. SDN flow rules installation was experimented to illustrate the post control function corresponding to DL-based output. The intelligent steering for network communication traffic is cooperatively configured in SDN controller and NFV-orchestrator to lead a variety of beneficial factors for improving massive real-time Internet of Things (IoT) performance.

• 태양에너지
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• 제6권2호
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• pp.3-14
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• 1986

It is desirable to collect the solar thermal energy at relatively high temperature in order to minimize the size of thermal storage system and to enlarge the scope of solar thermal energy utilization. In this study, to develop a solar collector that has both advantages of collecting solar thermal energy at high temperature and fixing conveniently the collector system for long term period, a cylindrical parabolique concentrating solar collector (M.C.P.C.S.C) was designed, which has several rows of parabolique reflectors and thin thickness such as the flat-plate solar collector, maintaining the optical form of concentrating solar collector. The thermal performance of the M.C.P.C.S.C. newly designed in this study was analysed theoretically and experimentally. The results are summarized as follows: 1) prediction equation for outlet temperature, $T_o$, of heat transfer fluid and for the thermal efficiency, ${\eta}$, of the collector were derived as; o $$T_o=[C+B1_n(\frac{I_c(t)}{pv^3})]T_i$$ o $${\eta}=\frac{A}{A_c}\dot{m}[(C-1)+B1_n(E{\cdot}di^6\frac{I_c(t)}{\dot{m}^3})]\frac{T_i}{I_c(t)}$$ 2) When the insolation on the tilted solar collector surface, $I_c$, was $900-950W/m^2$ and the heat transfer fluid was not circulated in tubular absorber, the maximum temperature on the absorber surface was $100-118^{\circ}C$, this result suggested that the heat transfer fluid could be heated up to $98-116^{\circ}C$. The maximum temperature on the absorber surface was decreased with the increase of the collector shape factor, $L_p/L_w$ 3) There was a good agreement between the experimental and theoretical value of solar collector efficiency, ${\eta}$, which was proportional to the collector shape factor, $L_p/L_w$ 4) It is desirable to continue the study on the relationship between the collector shape factor, $L_p/L_w$, and the thermal efficiency of solar collector.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
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• pp.807-811
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• 2003

In this paper, the speed control system of induction motor was proposed using vector control algorithm and space voltage vector PWM method to improve the dynamic performance of Induction motor. The control system is composed of the PI controller for speed control and the current controller using space voltage vector PWM technique. The high-speed calculation and processing for vector control is carried out by TMS320C31 digital signal processor and IGBT module. The proposed scheme is verified through digital simulations and experiments for 3.7[kw] induction motor and shows good dynamic performance.

• 동력기계공학회지
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• 제18권6호
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• pp.70-76
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• 2014

Surely fuel economy(F.E.) label is needed to meet consumer's right to know. Korea has developed and adopted F.E. correction equation similar to the feeling, because consumer complain about F.E. label higher than they feel. Recently, through continuous research and development high-efficiency & performance green car like HEV, PHEV and EV are being sold. In this situation, it is needed to know whether the current equation can reflect a part of their improved technic or not. In this paper, to review current equation through test using hybrid vehicles on 5-cycle SOC, correction equation and F.E were discussed. The result show HEV didn't meet the SOC error standard on US06. Also, HEV has bigger F.E. difference between FTP-75 and 5-cycle than conventional vehicles. However, the correction equation that include HEV almost same with current one.

• 융합보안논문지
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• 제11권1호
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• pp.39-48
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• 2011

QoS(Quality of Service)는 ITU-T Rec. E.800에 의해 서비스를 사용하는 형태, 특성 그리고 요구 수준에 따라 사용자의 요구에 부응하여 제공할 수 있는 네트워크 서비스의 성능지표로 표현된다. 네트워크를 활용하는 정보시스템에서 최종적인 목표는 요구되는 시간내에 목적하는 성능을 확보하는 것이다. 본 연구에서 제안하는 보안 QoS 프레임워크는 측정 메트릭스, 측정스케쥴, 측정도구, 측정의순서, 측정 결과분석에 관련된 사항으로 구성된다. 보안 QoS에서 네트워크보안의 정보보호기능과 시스템기능을 분리하여 관리하지 않고 연계하여 종합 메커니즘으로 구성 및 적용할 경우 종합적인 정보보호 효율은 시너지효과로 나타난다. 본 연구는 정보보호기능과 제반 시스템기능을 연계하여 정보보호기능을 적용했을 경우의 연동메커니즘 구현방법 개발과 그 성과를 측정하기 위한 것이다. 본 연구에서 제안한 네트워크 보안 효율성 제고를 위한 보안 QoS측정방안 연구 방법론을 통해 체계적인 측정환경을 설계할 경우 운용시스템상에서 보안 효율성 측정이 가능함이 입증되었고 측정 메커니즘을 통해서 개선된 네트워킹기능과 정보시스템 기능을 위한 효율성제고 방법론 개발이 가능함을 보여주고 있다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권8호
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• pp.4092-4104
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• 2017

In this paper, an efficient 4K and 8K UHD(Ultra High Definition) transmission scheme is proposed on the convergence networks with broadcasting and LTE(Long Term Evolution) by using CoMP(Coordinated Multi-Point). A video data is compressed and divided into BL(Base Layer), E(Enhanced layer)1, E2 and E3 by scalable HEVC(High Efficiency Video Coding). The divided layers can be combined by the scalable HEVC such as mobile HD, full HD, 4K and 8K UHD(Ultra High Definition). The divided layers are transmitted through the convergence networks with DVB-T2(Digital Video Broadcasting-$2^{nd}$ Generation Terrestrial) broadcasting system and LTE CoMP. This scheme transmits mobile HD and full HD layers through DVB-T2 broadcasting system by using M-PLP(Multiple-physical Layer Pipes), and adaptively transmits 4K or 8K UHD layer through LTE CoMP with MMT(MPEG Media Transport) server. An adaptive transmitting and receiving scheme in the LTE CoMP system provides 4K or 8K UHD layer to a user according to the user status. The proposed scheme is verified by showing the system-level simulation results which is better BER(bit-error-rate) performance than the conventional scheme. The results show that the proposed scheme provides the stable video contents to the user especially at the cell edge.

• 한국축산식품학회지
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• 제23권1호
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• pp.9-15
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• 2003

비육후기 돼지(LY $\times$ D, 90 kg 전후) 사료에 C는 대조구로 우지 5%, T1은 우지 3%에 들깨유를 2%우지 대체하였으며, T2는 T1에 비타민 E($\alpha$-tocopheryl acetate)를 250 ppm 첨가하였다. T3는 우지 3%에 오징어유를 2% 우지 대체하였으며, T4는 T3에 비타민 E를 250 ppm 첨가하였다. T5는 우지 3%에 CLA 2% 우지 대체 첨가 급여한 돼지의 생산 및 도체형 질을 조사한 결과는 다음과 같다. 일당 증체량은 T2와 T3가 다른 구들보다 높았으며(P<0.05) 사료요구율은 처리간에 유의적인 차이는 없으나 T2와 T3가 각각 3.71, 3.80으로 다소 양호하였다. 생체에서 등지방두께는 개시 체중시에는 처리간에 유의적인 차이를 보이지 않았으나 출하체중 시에는 C가 다른 처리구들보다 유의적으로 두꺼워 개시체중 대비 출하체중 시의 등지방두께 증가폭 역시 C가 넓었다. 배최장근 단면적은 개시체중 시나 출하체중 시에는 유의적인 차이는 없었으나 증가면에서는 T5가 T2에 비해서 약 2배 정도인 13.35 $\textrm{cm}^2$로 가장 높게 나타났다. 혈액 중 Triglyceride함량은 C가 다른 처리구들보다 높았으며, T3, T4, T5가 유의적으로 낮았다(P<0.05). 총 콜레스테롤 함량은 처리구들간에 유의적인 차이를 보이지 않았으며, 총 콜레스테롤 대비 HDL-콜레스테롤 비율은 비타민 E를 첨가하지 않은 구보다 첨가한 구들이 높게 나타났다. 동맥경화지수(AI: Atherogenic index)는 T3가 가장 높고 T2가 가장 낮았으며, 들깨유와 오징어유에 비타민 E 첨가로 낮아졌다. 도체형질에서 지육율과 등지방두께 및 등급은 처리간에 유의적인 차이를 보이지 않았으나(p>0.05) 등급에 있어 T2는 4.67, C와 T3는 4.29, T1과 T5는 4.00 수준이었다.operational requirements and typical plasma parameters have been determined. Large arrays of individual tiny sources can be used to form large-area, atmospheric-pressure plasma sources. The simplicity of the method and the capability of operation without the need for the usual vacuum system and its associated limitations, provide a highly attractive option for new approaches to many different kinds of plasma applications, including plasma surface modification technologies. Here we review the background work that has been carried out in this new research field.row$물엿으로 제조한 정과의 순으로 red에 가까웠다. b값(Yellowness)은 전처리한 동아 300g에 물 1$\ell$, 물엿 475$m\ell$을 넣고 5시간 동안 제조한 군이 가장 높아 yellow에 가까웠고 전체적으로 물엿$\longrightarrow$설탕과 꿀$\longrightarrow$물엿과 설탕으로 제조한 정과의 순으로 yellow에 가까웠다. 5. 관능검사에서 단단하다고 평가된 정과가 색도에서 적색도가 높았다. 관능검사에서 색이 좋다고 평가된 정과가 색도에서 붉은 빛과 황색을 나타냈다. 관능검사의 단단한 정도(Hardness)와 씹힘성(Chewinwss)은 기계검사의 Texture인 최대절단력(Maximum

• Advances in nano research
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• 제12권5호
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• pp.529-547
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• 2022

Graphene is one of the strongest, stiffest, and lightest nanoscale materials known to date, making it a potentially viable and attractive candidate for developing lightweight structural composites to prevent high-velocity ballistic impact, as commonly encountered in defense and space sectors. In-plane twist in bilayer graphene has recently revealed unprecedented electronic properties like superconductivity, which has now started attracting the attention for other multi-physical properties of such twisted structures. For example, the latest studies show that twisting can enhance the strength and stiffness of graphene by many folds, which in turn creates a strong rationale for their prospective exploitation in high-velocity impact. The present article investigates the ballistic performance of twisted bilayer graphene (tBLG) nanostructures. We have employed molecular dynamics (MD) simulations, augmented further by coupling gaussian process-based machine learning, for the nanoscale characterization of various tBLG structures with varying relative rotation angle (RRA). Spherical diamond impactors (with a diameter of 25Å) are enforced with high initial velocity (V_i) in the range of 1 km/s to 6.5 km/s to observe the ballistic performance of tBLG nanostructures. The specific penetration energy (E_p^*) of the impacted nanostructures and residual velocity (V_r) of the impactor are considered as the quantities of interest, wherein the effect of stochastic system parameters is computationally captured based on an efficient Gaussian process regression (GPR) based Monte Carlo simulation approach. A data-driven sensitivity analysis is carried out to quantify the relative importance of different critical system parameters. As an integral part of this study, we have deterministically investigated the resonant behaviour of graphene nanostructures, wherein the high-velocity impact is used as the initial actuation mechanism. The comprehensive dynamic investigation of bilayer graphene under the ballistic impact, as presented in this paper including the effect of twisting and random disorder for their prospective exploitation, would lead to the development of improved impact-resistant lightweight materials.

• 한국산학기술학회논문지
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• 제21권5호
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• pp.664-671
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• 2020

스마트 빌딩 (Smart Building)은 사물 인터넷 (IoT; Internet of Things) 장치와 클라우드 서비스에서 모두 사용될 수 있는 응응 프로그램을 의미한다. 최근 Amazon, Google 및 Microsoft와 같은 클라우드 서비스 제공 업체는 IoT 장치에서 클라우드 애플리케이션 서비스를 제공할 수 있는 IoT 클라우드 플랫폼을 제공하고 있다. Postscapes에 따르면 최근에 152 개의 IoT 클라우드 플랫폼이 존재하고 있으며 스마트 빌딩 구현을 위해 하나를 선택하는 것은 어려운 문제이다. 본 논문에서는 실험을 위해서 마이크로소프트 Azure IoT 허브와 아마존의 AWS(Amazon Web Services) IoT를 선택하였다. 두 개의 IoT 클라우드 플랫폼을 선택하고 스마트 빌딩 관점에서 평가하였다. IoT 클라우드 플랫폼을 평가하기 위해 두 가지 다른 IoT 클라우드 플랫폼을 활용하였고, 일반적인 스마트 빌딩 시나리오를 가정하여 프로토타입을 구현하였다. 실험은 IoT 클라우드 플랫폼을 사용하여 시스템을 개발하는 과정에서 얻은 정보와 경험을 기반으로 수행하였다. 이 평가 결과는 스마트 빌딩을 위해 IoT 클라우드 플랫폼을 선택할 때 활용될 수 있다.