• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11a
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• pp.155-160
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• 2001

Actual engineering structure is frequently very complex, and parts of structure are designed independently by different engineers. Also each structure contains so many degree of freedom. For these reason, methods have been developed which permits the structure to be divided into components or substructures, with analysis being done on a small substructure in order to obtain a full structural system. In such case, because of different mesh size among finite element model (FEM) or different matching points among FEM models and experimentally obtained models, their interfacing points may be non-matching. Solving this non-matching problem is useful to other application such as structural dynamic modification or model updating. In this work, virtual node concept is introduced. Lagrange multipliers are used to enforce the interface compatibility constraint, and interface displacement is approximated by polynomial presentation. The governing equation of whole structure is derived using hybrid variational principle. The eigenvalue of whole structure are calculated using the determinant search method. The number of degree of freedom in the eigenvalue problem can be drastically reduced to just the number of interface degree of freedom. Some numerical simulation is performed to show usefulness of synthesis method.

• Korean Journal of Social Welfare
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• v.46
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• pp.178-209
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• 2001

This paper aims to provide a critical assesment of Conservatives's and new Labour's social assistance reforms in the U.K. and their differential impacts on low income groups. During the period of 18 years in power, the Conservative governments enforced benefit recipients being capable of work to be out of benefits and to get into work. They employed not only 'carrots' to encourage beneficiaries being capable of work to have full-time work, but also 'sticks' to discourage them to depend on benefits. The reforms under the Conservative governments were closer to the workfare model. The new Labour government has continued to emphasize work regarding social security reform. It has raised 'from welfare to work' as the main reform objective. However, it has not necessarily focused on 'carrots and sticks' in order to get beneficiaries into work. Instead, the new Labour government has put its priority regarding social assistance reform on human capital development in order to develop the capability of beneficiaries for work. Britain under the new Labour government seems to be moving from workfare to activation model. These differentials between the Conservative governments and the new Labour government regarding social assistance reforms bring about the different policy outcomes. Under the Conservative government, social assistance programmes were prone to strengthen the state's control over benefit recipients and to increase stigma to them. Punitive, demeaning, stigmatising programmes of work and unending job search activities harm the bases of self-respect. On the contrary, the activation programmes under the new Labour government has contributed positively to both socially significant participation and autonomy of beneficiaries.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.1
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• pp.130-140
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• 1998

This paper presents a method to estimate subpixel accuracy motion vectors using a mathermatical model withoug interpolation. the proposed method decides the coefficients of mathematical model, which represents the motion vector which is achieved by full search. And then the proposed method estimates subpixel accuracy motion vector from achieved mathematical model. Step by step mathematical models such as type 1, type 2, type 3, modified bype 2, modified type 3, and Partial Interpolation type 3 are presented. In type 1, quadratic polynomial, which has 9 unknown coefficients and models the 3by 3 pixel plane, is used to get the subpixel accuracy motion vectors by inverse matrix solution. In type 2 and 3, each quadratic polynomial which is simplified from type 1 has 5 and 6 unknown coefficients and is used by least square solution. Modified type 2 and modified type 3 are enhanced models by weighting only 5 pixels out of 9. P.I. type 3 is more accurate method by partial interpolation around subpixel which isachieved by type 3. LThese simulation results show that the more delicate model has the better performance and modified models which are simplified have excellent performance with reduced computational complexity.

• Journal of Electrical Engineering and Technology
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• v.11 no.3
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• pp.715-723
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• 2016

This paper proposes a design of optimal PI(D) controller for brushless DC (BLDC) motor speed control by the particle swarm optimization (PSO), one of the powerful metaheuristic optimization search techniques. The proposed control system is implemented on the TMS320F28335 DSP board interfacing to MATLAB/SIMULINK. With Back EMF detection, the proposed system is considered as a class of sensorless control. This scheme leads to the speed adjustment of the BLDC motor by PWM. In this work, the BLDC motor of 100 watt is conducted to investigate the control performance. As results, it was found that the speed response of BLDC motor can be regulated at the operating speed of 800 and 1200 rpm in both no load and full load conditions. Very satisfactory responses of the BLDC system can be successfully achieved by the proposed control structure and PSO-based design approach.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2013.11a
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• pp.223-226
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• 2013

정확한 움직임 추정 기술은 원본과 가장 유사한 영상의 복원에 효과적이고 압축률에도 중요한 영향을 미친다. 하지만 기존의 전역 탐색 (Full Search) 알고리듬과 Sum of Absolute Difference (SAD)라는 정합 오차 기준은 연산량이 높고 하드웨어 구현시 비효율적이다. 이를 보완하기 위한 1비트 변환 알고리듬은 움직임 벡터의 변화량을 0과 1의 연산으로 나타내는데, 이 알고리듬은 움직임이 많아 픽셀 값의 변화가 심한 블록의 변화량도 0과 1로만 표현한다. 그렇기 때문에 정확한 움직임이 반영되지 않고 그로 인해 낮은 Peak Siganl to Noise Ratio (PSNR)을 가져온다. 이 점을 개선하고자 본 논문에서는 참조블록들의 움직임 벡터를 파악하고 분류하여 선택적으로 움직임의 변화량이 큰 영역은 전역 탐색 알고리듬을, 움직임이 작거나 없는 영역은 1비트 연산을 수행하도록 하여 기존의 알고리듬과 비교하여 Peak Siganl to Noise Ratio (PSNR)측면에서 우수한 성능을 확인할 수 있었다.

• Journal of Advanced Navigation Technology
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• v.10 no.4
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• pp.400-405
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• 2006

In this paper, we propose a moving object tracking algorithm by using motion estimation in UAV(Unmanned Aerial Vehicle) video. Proposed algorithm is based on generation of initial image from detected reference image, and tracking of moving object under the time-varying image. With a series of this procedure, tracking process is stable even when the UAV camera sways by correcting position of moving object, and tracking time is relatively reduced. A block matching algorithm is also utilized to determine the similarity between reference image and moving object. An experimental result shows that our proposed algorithm is better than the existing full search algorithm.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.286-289
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• 2009

This paper presents an effective approach to minimize recursive computations for balancing stereo pairs by using disparity vector errors and its directional histogram. A stereo balancing function is computed from the correspondent pixels between two images, and a simple approach is to find the matching blocks of two images. However, this procedure requires recursive operation, and its computation cost is very high. Therefore, in this paper, we propose an efficient balance method using structural similarity index and a partial re-searching scheme to reduce the computation cost considerably. For this purpose, we determine if re-searching for each block is necessary or not by using the errors and the directional histogram of disparity vectors. Experiment results show that the performance of the proposed approach can save the computations significantly with ignorable image quality degradation compared with full re-search approach.

• The Korean Journal of Pain
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• v.19 no.2
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• pp.164-167
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• 2006

Background: There have been an increasing number of reports about infection-related complications after epidural block, and the analysis of these previous reports may offer valuable information for the prevention and treatment of such complications. Methods: We searched for complications about infection that was related to epidural blockade procedures by using the Medline Search program. We analyzed the types of infection-related complications as well as the potential risk factors, the time course from symptom development to treatment, the causative organisms and the treatment outcomes. Results: Seventeen cases were identified. The types of complications were epidural abscess, subdural abscess, spinal arachnoiditis, bacterial meningitis and aseptic meningitis. Five patients received a single block and twelve patients received a continuous block with catheterization. The most common site of epidural catheterization was the lumbar area and eight patients had indwelling catheters for less than fifteen days. Eight patients had a diabetes mellitus as a risk factor and fourteen patients showed less than seven days from the development of symptoms to treatment. Eleven patients received laminectomy and intravenous antibiotics as a treatment and eight patients had full recovery without neurological deficit. Conclusions: Early diagnosis and treatment is essential for the favorable outcome of infection-related complication after epidural block. In addition, absolute sterile technique should always be performed and patient education concerning these potential complications must be accompanied.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.7
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• pp.369-378
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• 2020

The paper aims to identify the determinants that influence entrepreneurial intention among National Economics University graduates. For the sample size, we conducted a questionnaire survey of 250 full-time third-year undergraduates at the National Economics University, with convenience sampling technique. Of those 250 undergraduates, 150 were Business Administration students and 100 Economy Management students. After eliminating invalid responses due to lack of information or low quality information, 215 responses were used (93.07% of respondents) for data analysis. The results show that the factor "Perceived desirability" has the strongest impact on the intention to start a business. It is followed by the factor "Perceived feasibility" in which the "ability to search and plan for start-up" has a stronger influence on undergraduates' entrepreneurial intention than the "leadership and ability to overcome adversity". The hypothesis of a positive relationship between undergraduates' propensity to act and their intention to start a business is also supported in this study. Based on the results, we suggest some recommendations for the university and State management agencies to nurture and develop entrepreneurial intention of undergraduates, forming the young generation of potential entrepreneurs to contribute to the development of emerging countries such as Vietnam, the case study.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.4
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• pp.1611-1629
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• 2016

Recently, deploying WiFi access points (APs) for facilitating indoor localization has attracted increasing attention. However, most existing mechanisms in this aspect are typically simulation based and further they did not consider how to jointly utilize pre-existing APs in target environment and newly deployed APs for achieving high localization performance. In this paper, we propose a measurement-based AP deployment mechanism (MAPD) for placing APs in target indoor environment for assisting fingerprint based indoor localization. In the mechanism design, MAPD takes full consideration of pre-existing APs to assist the selection of good candidate positions for deploying new APs. For this purpose, we first choose a number of candidate positions with low location accuracy on a radio map calibrated using the pre-existing APs and then use over-deployment and on-site measurement to determine the actual positions for AP deployment. MAPD uses minimal mean location error and progressive greedy search for actual AP position selection. Experimental results demonstrate that MAPD can largely reduce the localization error as compared with existing work.