• Title/Summary/Keyword: optimization scheme

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A Comparative Study of Classification Systems for Organizing a KOS Registry (KOS 레지스트리 구조화를 위한 분류체계 비교 연구)

  • Ziyoung Park
    • Journal of the Korean Society for Library and Information Science
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    • v.58 no.2
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    • pp.269-288
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    • 2024
  • To structure the KOS registry, it is necessary to select a classification system that suits the characteristics of the collected KOS. This study aimed to classify domestic KOS collected through various classification schems, and based on these results, provide insights for selecting a classification system when structuring the KOS registry. A total of 313 KOS data collected via web searches were categorized using five types of classification systems and a thesaurus, and the results were analyzed. The analysis indicated that for international linkage of the KOS registry, foreign classification systems should be applied, and for optimization with domestic knowledge resources or to cater to domestic researchers, domestic classification systems need to be applied. Additionally, depending on the field-specific characteristics of the KOS, research area KOS should apply classification systems based on academic disciplines, while public sector KOS should consider classification systems based on government functions. Lastly, it is necessary to strengthen the linkage between domestic and international KOS, which also requires the application of multiple classification systems.

Transformation of Dynamic Loads into Equivalent Static Load based on the Stress Constraint Conditions (응력 구속조건을 고려한 동하중의 등가정하중으로의 변환)

  • Kim, Hyun-Gi;Kim, Euiyoung;Cho, Maenghyo
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.26 no.2
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    • pp.165-171
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    • 2013
  • Due to the difficulty in considering dynamic load in the view point of a computer resource and computing time, it is common that external load is assumed as ideal static loads. However, structural analysis under static load cannot guarantee the safety of design of the structures under dynamic loadings. Recently, the systematic method to construct equivalent static load from the given dynamic load has been proposed. Previous study has calculated equivalent static load through the optimization procedure under displacement constraints. However, previously reported works to distribute equivalent static load were based on ad-hoc methods. Improper selection of equivalent static loading positions may results in unreliable prediction of structural design. The present study proposes the selection method of the proper locations of equivalent static loads to dynamically applied loads when we consider transient dynamic structural problems. Moreover, it is appropriate to take into account the stress constraint as well as displacement constraint condition for the safety design. But the previously reported studies of equivalent static load design methods considered only displacement constraint conditions but not stress constraint conditions. In the present study we consider not only displacement constraint but also stress constraint conditions. Through a few numerical examples, the efficiency and reliability of proposed scheme is verified by comparison of the equivalent stress between equivalent static loading and dynamic loading.

A PAPR Reduction Technique by the Partial Transmit Reduction Sequences (부분 전송 감소열에 의한 첨두대 평균 전력비 저감 기법)

  • Han Tae-Young;Yoo Young-Dae;Choi Jung-Hun;Kwon Young-Soo;Kim Nam
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.17 no.6 s.109
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    • pp.562-573
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    • 2006
  • It is required to reduce the peak-to-average power ratio(PAPR) in an orthogonal frequency division multiplexing system or a multicarrier system. And it is needed to eliminate the transmission of the side information in the Partial Transmit Sequences. So, in this paper, a new technique is proposed, where the subcarriers used for the multiple signal representation are only utilized for the reduction of PAPR to eliminate the burden of transmitting the side information. That is, it is proposed by taking the modified minimization criteria of partial transmit sequences scheme instead of using the convex optimization or the fast algorithm of tone reservation(TR) technique As the result of simulation, the PAPR reduction capability of the proposed method is improved by 3.2 dB dB, 3.4 dB, 3.6 dB with M=2, 4, 8(M is the number of partition in the so-called partial transmit reduction sequences(PTRS)), when the iteration number of fast algorithm of TR is 10 and the data rate loss is 5 %. But it is degraded in the capability of PAPR reduction by 3.4 dB, 3.1 dB, 2.2 dB, comparing to the TR when the data rate loss is 20 %. Therefore, the proposed method is outperformed the TR technique with respect to the complexity and PAPR reduction capability when M=2.

Depth Upsampling Method Using Total Generalized Variation (일반적 총변이를 이용한 깊이맵 업샘플링 방법)

  • Hong, Su-Min;Ho, Yo-Sung
    • Journal of Broadcast Engineering
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    • v.21 no.6
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    • pp.957-964
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    • 2016
  • Acquisition of reliable depth maps is a critical requirement in many applications such as 3D videos and free-viewpoint TV. Depth information can be obtained from the object directly using physical sensors, such as infrared ray (IR) sensors. Recently, Time-of-Flight (ToF) range camera including KINECT depth camera became popular alternatives for dense depth sensing. Although ToF cameras can capture depth information for object in real time, but are noisy and subject to low resolutions. Recently, filter-based depth up-sampling algorithms such as joint bilateral upsampling (JBU) and noise-aware filter for depth up-sampling (NAFDU) have been proposed to get high quality depth information. However, these methods often lead to texture copying in the upsampled depth map. To overcome this limitation, we formulate a convex optimization problem using higher order regularization for depth map upsampling. We decrease the texture copying problem of the upsampled depth map by using edge weighting term that chosen by the edge information. Experimental results have shown that our scheme produced more reliable depth maps compared with previous methods.

Enrollment Elevation to the Chinese International Students in Local Universities in Korea (한국 지방대학의 중국유학생 유치·관리방안)

  • Chung, Kyoun-Sup;Lei, Song-Lin;Sim, Moon-Bo
    • The Journal of the Korea Contents Association
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    • v.10 no.8
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    • pp.327-340
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    • 2010
  • Since South Korea has problems existing in the respects of educational resources, environment, policies, etc., local universities of South Korea have been in an inferior position in the competition of overseas student enrollment. With increasingly deepening of cultural exchange between China and South Korea, due to geographic close relationship between the two countries, a great number of South Korean students go to China for study; also, Chinese students have increasingly become the important target of recruitment by all local universities in South Korea. In recent years, with rapid increase in the number of Chinese students in South Korea, the overseas student education system of South Korea has been progressed continuously. Compared with educational advantages of universities in European, American developed countries, and the capital region of South Korea, however there still exists a lot of problems in Chinese student recruitment by local universities. The major findings of the study can be summarized as follows. There exist not only some advantages but also some problems to be addressed urgently in Chinese student enrollment by South Korean local universities. How to build a distinctive recruitment environment suitable for Chinese students; and, how to develop a complete "one-stop" educational system suitable for study; and, how to make a strategy of development for Chinese students; and, how to perfect set up the overseas students' education management system; which are the remaining tasks to be solved for. To achieve a win-win for both overseas students and South Korean local universities, it is very important and urgent works to do for administrators of Chinese students in all local universities of South Korea.

An Improved Algorithm for Building Multi-dimensional Histograms with Overlapped Buckets (중첩된 버킷을 사용하는 다차원 히스토그램에 대한 개선된 알고리즘)

  • 문진영;심규석
    • Journal of KIISE:Databases
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    • v.30 no.3
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    • pp.336-349
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    • 2003
  • Histograms have been getting a lot of attention recently. Histograms are commonly utilized in commercial database systems to capture attribute value distributions for query optimization Recently, in the advent of researches on approximate query answering and stream data, the interests in histograms are widely being spread. The simplest approach assumes that the attributes in relational tables are independent by AVI(Attribute Value Independence) assumption. However, this assumption is not generally valid for real-life datasets. To alleviate the problem of approximation on multi-dimensional data with multiple one-dimensional histograms, several techniques such as wavelet, random sampling and multi-dimensional histograms are proposed. Among them, GENHIST is a multi-dimensional histogram that is designed to approximate the data distribution with real attributes. It uses overlapping buckets that allow more efficient approximation on the data distribution. In this paper, we propose a scheme, OPT that can determine the optimal frequencies of overlapped buckets that minimize the SSE(Sum Squared Error). A histogram with overlapping buckets is first generated by GENHIST and OPT can improve the histogram by calculating the optimal frequency for each bucket. Our experimental result confirms that our technique can improve the accuracy of histograms generated by GENHIST significantly.

Process Alignment between MND-AF and ADDMe for Products Reusability (산출물 재사용성을 위한 MND-AF와 ADDMe 프로세스 정렬)

  • Bu, Yong-Hee;Lee, Tae-Gong
    • Journal of the military operations research society of Korea
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    • v.32 no.2
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    • pp.131-142
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    • 2006
  • Nowadays, most enterprises have introduced both EA methodology to optimize an entire enterprise and CBD methodology to improve a software reusability. The Korea Government not only have developed many EA guiding products such as EA framework, Reference Model, Guideline, etc. but also have instituted a law to optimize a government-wide enterprise. The Minister of National Defense(MND) have developed the MND-AF as a standard methodology for EA and the ADDMe as a standard methodology for CBD. But it is possible to develop products of WD-AF and ADDMe redundantly because the process of MND-AF and ADDMe is not quitely aligned. The purpose of this paper is to present a scheme that ADDMe can reuse the artifacts of MND-AF by analyzing the relationships between two processes. In order to identify the relationships between two processes, we first identify the relation of a 'definition' part of two processes and then identify the relation of an 'attribute' part based on the relation of a 'detailed definition' part. As a result we found that 113 attributes of MND-AF are related to 49 attributes of ADDMe. Therefore the proposed study will decrease the development cost and time and will be a good example for aligning the process of EA and CBD methodology.

A Study on the PAPR Reduction Using Phase Rotation Method Applying Metaheuristic Algorithm (Metaheuristic 알고리즘을 적용한 위상회전 기법에 의한 PAPR 감소에 관한 연구)

  • Yoo, Sun-Yong;Park, Bee-Ho;Kim, Wan-Tae;Cho, Sung-Joon
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.46 no.5
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    • pp.26-35
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    • 2009
  • OFDM (Orthogonal Frequency Division Multiplexing) system is robust to frequency selective fading and narrowband interference in high-speed data communications. However, an OFDM signal consists of a number of independently modulated subcarriers and the superposition of these subcarriers causes a problem that can give a large PAPR(Peak-to-Average Power Ratio). Phase rotation method can reduce the PAPR without nonlinear distortion by multiplying phase weighting factors. But computational complexity of searching phase weighting factors is increased exponentially with the number of subblocks and considered phase factor. Therefore, a new method, which can reduce computational complexity and detect phase weighting factors efficiently, should be developed. In this paper, a modeling process is introduced, which apply metaheuristic algerian in phase rotation method and optimize in PTS (Particle Swarm Optimization) scheme. Proposed algorithm can solve the computational complexity and guarantee to reduce PAPR We analyzed the efficiency of the PAPR reduction through a simulation when we applied the proposed method to telecommunication systems.

Application of Au-Sn Eutectic Bonding in Hermetic Rf MEMS Wafer Level Packaging (Au-Sn 공정 접합을 이용한 RF MEMS 소자의 Hermetic 웨이퍼 레벨 패키징)

  • Wang Qian;Kim Woonbae;Choa Sung-Hoon;Jung Kyudong;Hwang Junsik;Lee Moonchul;Moon Changyoul;Song Insang
    • Journal of the Microelectronics and Packaging Society
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    • v.12 no.3 s.36
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    • pp.197-205
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    • 2005
  • Development of the packaging is one of the critical issues for commercialization of the RF-MEMS devices. RF MEMS package should be designed to have small size, hermetic protection, good RF performance and high reliability. In addition, packaging should be conducted at sufficiently low temperature. In this paper, a low temperature hermetic wafer level packaging scheme for the RF-MEMS devices is presented. For hermetic sealing, Au-Sn eutectic bonding technology at the temperature below $300{\times}C$ is used. Au-Sn multilayer metallization with a square loop of $70{\mu}m$ in width is performed. The electrical feed-through is achieved by the vertical through-hole via filled with electroplated Cu. The size of the MEMS Package is $1mm\times1mm\times700{\mu}m$. By applying $O_2$ plasma ashing and fabrication process optimization, we can achieve the void-free structure within the bonding interface as well as via hole. The shear strength and hermeticity of the package satisfy the requirements of MIL-STD-883F. Any organic gases or contamination are not observed inside the package. The total insertion loss for the packaging is 0.075 dB at 2 GHz. Furthermore, the robustness of the package is demonstrated by observing no performance degradation and physical damage of the package after several reliability tests.

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An Optimal Design of Neuro-Fuzzy Logic Controller Using Lamarckian Co-adaptation of Learning and Evolution (학습과 진화의 Lamarckian 상호 적응에 의한 뉴로-퍼지 제어기의 최적 설계)

  • 김대진;이한별;강대성
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.35C no.12
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    • pp.85-98
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    • 1998
  • This paper proposes a new design method of neuro-FLC by the Lamarckian co-adaptation scheme that incorporates the backpropagation learning into the GA evolution in an attempt to find optimal design parameters (fuzzy rule base and membership functions) of application-specific FLC. The design parameters are determined by evolution and learning in a way that the evolution performs the global search and makes inter-FLC parameter adjustments in order to obtain both the optimal rule base having high covering value and small number of useful fuzzy rules and the optimal membership functions having small approximation error and good control performance while the learning performs the local search and makes intra-FLC parameter adjustments by interacting each FLC with its environment. The proposed co-adaptive design method produces better approximation ability because it includes the backpropagation learning in every generation of GA evolution, shows better control performance because the used COG defuzzifier computes the crisp value accurately, and requires small workspace because the optimization procedure of fuzzy rule base and membership functions is performed concurrently by an integrated fitness function on the same fuzzy partition. Simulation results show that the Lamarckian co-adapted FLC produces the most superior one among the differently generated FLCs in all aspects such as the number of fuzzy rules, the approximation ability, and the control performance.

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