• Title/Summary/Keyword: Case Adaptation

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Power and Rate Adaptations in Multi-carrier DS/CDMA Communications over Rayleigh Fading Channel (레일레이 패이딩 채널에서 다중 반송자 DS/CDMA 통신 시스템의 전력-전송율 적응 방식)

  • Ah Heejune;Lee Ye Hoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.6C
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    • pp.423-433
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    • 2005
  • We present power(in frequency domain) and rate adaptation(in time domain) schemes in multicarrier (MC) direct-sequence code-division multiple-access(DS/CDMA) communications. Utilizing channel state information from the receiver, the adaptation schemes allocate power the user's sub-band with the largest channel gain. In the time domain, the transmission data rate is adapted for a desired transmission quality. In the case of single-user channels, a closed-form expression is derived for an optimal time domain power adaptation that minimizes the average bit error rate(BER). Channel inversion power adaptation is found to provide nearly optimal performance in this case, as the number of sub-bands or available average transmission power increase. Analysis and simulation results show the BER performance of the proposed power and rate adaptations with fixed average transmission power significantly improves the performance over the power allocation in the frequency domain only. Also, we compare the performance of the proposed power and rate adaptation schemes in MC-DS/CDMA systems with that of power and rate adapted single carrier DS/CDMA systems with RAKE receiver.

On Codebook Design to Improve Speaker Adaptation (음성 인식 시스템의 화자 적응 성능 향상을 위한 코드북 설계)

  • Yang, Tae-Young;Shin, Won-Ho;Kim, Weon-Goo;Youn, Dae-Hee
    • The Journal of the Acoustical Society of Korea
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    • v.15 no.2
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    • pp.5-11
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    • 1996
  • The purpose of this paper is to propose a method improving the performance of a semi-continuous hidden Markov model(SCHMM) speaker adaptation system which uses Bayesian Parameter reestimation approach. The performance of Bayesian speaker adaptation could be degraded in case that the features of a new speaker are severely different from those of a reference codebook. The excessive codewords of the reference codebook still remain after adaptation proess. which cause confusion in recognition process. To solve such problems, the proposed method uses formant information which is extracted from the cepstral coefficients of the reference codebook and adaptation data. The reference codebook is adapted to represent the formant distribution of a new speaker and it is used for Bayesian speaker adaptation as an initial codebook. The proposed method provides accurate correspondence between reference codebook and adaptation data. It was observed that the excessive codewords were not selected during recognition process. The experimental results showed that the proposed method improved the recognition performance.

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Numerical Simulation of Shock Wave Reflecting Patterns for Different Flow Conditions

  • Choi, Sung-Yoon;Oh, Se-Jong
    • International Journal of Aeronautical and Space Sciences
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    • v.3 no.1
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    • pp.74-85
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    • 2002
  • The numerical experiment has been conducted to investigate the unsteady shock wave reflecting phenomena. The cell-vertex finite-volume, Roe's upwind flux difference splitting method with unstructured grid is implemented to solve unsteady Euler equations. The $4^{th}$-order Runge-Kutta method is applied for time integration. A linear reconstruction of the flux vector using the least-square method is applied to obtain the $2^{nd}$-order accuracy for the spatial derivatives. For a better resolution of the shock wave and slipline, the dynamic grid adaptation technique is adopted. The new concept of grid adaptation technique, which is much simpler than that of conventional techniques, is introduced for the current study. Three error indicators (divergence and curl of velocity, and gradient of density) are used for the grid adaptation procedure. Considering the quality of the solution and the numerical efficiency, the grid adaptation procedure was updated up to $2^{nd}$ level at every 20 time steps. For the convenience of comparison with other experimental and analytical results, the case of interaction between the straight incoming shock wave and a sharp wedge is simulated for various flow conditions. The numerical results show good agreement with other experimental and analytical results, in the shock wave reflecting structure, slipline, and the trajectory of the triple points. Some critical cases show disagreement with the analytical results, but these cases also have been proven to show hysteresis phenomena.

A Study on the Method of Urban Planning for Adaptation to Climate Change (기후변화 적응을 위한 도시계획 방안 연구)

  • Lee, Sung Hee;Kim, Jong Kon
    • Journal of Climate Change Research
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    • v.5 no.3
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    • pp.257-266
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    • 2014
  • This study aims to understand abnormal climate caused by impacts of climate change and to suggest the direction of urban planning focusing on adaptation to climate change. The study consists of theory consideration and case study(Chicago, Philadelphia, Seattle). As a result, the main impacts of climate change faced by urban areas are heat wave, precipitation, and drought. To prevent these impacts, it is important to prepare methods of urban planning as followings: planning for land use, park and green considering the climate patterns, establishing and managing water resources systems similar to the nature, securing renewable energy resources, and transportation facilities and exterior space with proof against climate. It is especially necessary to introduce infrastructures related to storm water, green roof, shading tree planting, green space, and permeable pavement. Finally, in order to realize urban planning for adaptation to climate change, it is needed to make the detailed and specific goal and strategy for the climate change adaptation plan and to extend the scope from the goals to an action plan, a detailed plan, and a design guideline.

The Rules of law for the Hardship in the UNIDROIT Principles of International Commercial Contracts (국제상사계약에 관한 UNIDROIT원칙에 있어서 이행곤란(Hardship)의 법리)

  • Hong, Sung Kyu;Kim, Yong Il
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.57
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    • pp.3-34
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    • 2013
  • In the international sales contract, long-term contracts often face hardship in fulfilling the original contract terms by relevant parties due to rapid change and uncertainty of political and economic circumstance. In this case, party who faces hardship of fulfillment terminates contract or demands adaptation to contract condition but if opponent doesn't accept this, it proceeds to commercial dispute needing legal interpretation. Generally it is wise to set forth governing law in contract between parties in the case of international contract, for legal stability. One of universal governing law which relevant parties select by agreement to solve economical hardship of fulfillment is PICC. PICC defines the hardship in detail for renegotiation on following hardship of fulfillment unexpected. In the case of failing renegotiation, Court(arbitral tribunal) conducts termination to contract or adaptation to contract condition through arbitration or mediation. In conclusion, when signing international long-term contract, it is desirous to handle dispute effectively by inserting provisions which can deal with economical hardship in contract or defining PICC as governing law in the case of hardship incurred. It is because it is realistic to handle dispute smoothly to the extent that both parties can be satisfied in the case of hardship incurred, though international contract should be fulfilled.

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A Case Study on the Experience of Adaptation Process of Life of Children Whose Parents are Imprisoned (부모 수감 후 남겨진 자녀의 삶의 적응과정 경험에 관한 사례연구)

  • Choi, Kyoung Ok;Lee, Kyung Rim
    • Korean Journal of Family Social Work
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    • no.62
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    • pp.171-206
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    • 2018
  • The purpose of this study is to understand the experience how children are receptive to their parents' imprisonment, adaptation from their painful experience and crisis. In order to achieve the purpose of the study, six youth participants were selected. We carried out in-depth individual interviews and the collected data from the interviews and the case study were analyzed. The commons subjects are like 'Sudden separation and shock', 'Glad to be unhappy', 'Wretched my life', 'The way of the far-away meeting', 'The one who gave me hope', 'Live my life'and so on. Based on the result of this study, policy and practical guideline were discussed and suggested to help children of the incarcerated in addition to the limitations of the study and the recommendations for further study.

The Effect of Prism Adaptation Following Traumatic Brain Injury: A case report

  • Jeong, Eun-Hwa;Min, Yoo-Seon
    • Therapeutic Science for Rehabilitation
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    • v.6 no.2
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    • pp.37-45
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    • 2017
  • Background: The presence of visuospatial impairment can make patients slow functional recovery and impede the rehabilitation process in TBI patients. Objective: The aim of this study is to investigate effects of prism adaptation treatment for functional outcomes in patients following traumatic brain injury. Methods: The subject received prism adaptation treatment for 2 weeks additionally during traditional rehabilitation for 4 weeks. The Patient has prism adaptation treatment while wearing wedge prisms that shift the external environment about $12^{\circ}$ leftward. The patient received 10 sessions, 15-20min each session. Outcome measures were visuospatial deficit(line bisection, latter cancellation), Visual and spatial perception(LOTCA-visual perception and spatial perception), motor function of upper extremity(FMA U/E; Fugl-Meyer motor assessment upper extremity, ARAT; Action research arm test), balance(BBS; Berg Balance Scale), mobility(FAC; Functional ambulation classification) and functional level(FIM; Functional independent measure). All Assessments took place on study entry and post-treatment assessments were performed at discharge from the hospital. Results: After prism adaptation, the visuospatial impairment scores improved as indicated in the line bisection(-15.2 to -6.02), latter cancellation(2 to 0) and LOTCA- spatial perception scores(7 to 9). The upper motor function improved as indicated in the scores of affected FMA U/E(21 to 40) and ARAT(4 to 22). Ambulation and balance improved as indicated in the BBS scores(25 to 38) and FAC scores(0 to 4). ADL function improved as indicated in the FIM total scores 54 to 70(motor 34 to 61, cognition 20 to 29). Conclusion: Prism adaptation did improve functional level such as motor functions and ADL abilities in TBI patient. Further research is recommended.

Determinant Factors of Rice Farmers' Selection of Adaptation Methods to Climate Change in Eastern Rwanda (동부 르완다 쌀 농업인의 기후변화에 대한 적응 방법 결정 요인)

  • Butera, Tonny;Kim, Tae-Kyun;Choi, Se-Hyun
    • Korean Journal of Organic Agriculture
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    • v.30 no.2
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    • pp.241-253
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    • 2022
  • The negative impact of climate change on the agricultural sector is rapidly increasing, and it is urgent to prepare policies at the government level to mitigate it. In the case of Rwanda's agricultural sector, which lacks the government's budget and farmers' capital, efficient and effective policy implementation is of paramount importance. To this end, rather than establishing related policies in the public sector from the top down, it is necessary to establish a bottom-up customized policy that is reflected in policy establishment by identifying the characteristics and behaviors of farmers who actually participate in adaptation activities. In this study, the effects of farmers' characteristics and farmers' perception status/adaptation status to climate change on the selection of adaptation methods for climate change were analyzed. 357 rice farmers randomly selected from Eastern Rwanda were surveyed to explore the information related to farmers' perception to climate change and adaptation methods as well as basic information of the farm. Research shows that the probability of selecting a variety of adaptation methods rather than not responding to climate change increases the younger the age, the higher the education level, and the easier access to climate information and credit. As a policy proposals, it is judged that public support such as strengthening agricultural technology support services, including more detailed guidance for elderly and low-educated farmers, and improving access to farm loan services by agricultural financial institutions is needed. In addition, it is necessary to adjust the planting time and cultivation method, provide timely information related to climate change, and provide crop variety improvement services to farmers.

A nonlinear adaptive equalizer with fast on-line adaptation (고속 온라인 적응기능을 갖는 비선형 적응등화기)

  • 오덕길;최진영;이충웅
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.32A no.8
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    • pp.11-18
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    • 1995
  • This paper proposes a nonlinear adaptive equalizer which is based on fuzzy rules and fuzzy inference of several affine mapping for the received channel data. The proposed nolonlinear adaptive equalizers with the significantly lower computational complexity. Also it can be applied to the on-line adaptation environments owing to its fast convergence characteristics and the lower computational load. When using the decision feedback vectors, this equaalizer can be easily realized in the form of the DFE structure with out the requirement for the perfect channel knowledge as in the case of the fuzzy adaptive filter.

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JCBP : A Case-Based Planning System (JCBP : 사례 기반 계획 시스템)

  • Kim, In-Cheol;Kim, Man-Soo
    • Journal of Intelligence and Information Systems
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    • v.14 no.4
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    • pp.1-18
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    • 2008
  • By using previous similar case plans, the case-based planning (CBP) systems can generate efficiently plans for new problems. However, most existing CBP systems show limited functionalities for case retrieval and case generalization. Moreover, they do not allow their users to participate in the process of plan generation. To support efficient memory use and case retrieval, the proposed case-based planning system, JCBP, groups the set of cases sharing the same goal in each domain into individual case bases and maintains indexes to these individual case bases. The system applies the heuristic knowledge automatically extracted from the problem model to the case adaptation phase. It provides a sort of case generalization through goal regression. Also JCBP can operate in an interactive mode to support a mixed-initiative planning. Since it considers and utilizes user's preference and knowledge for solving the given planning problems, it can generate solution plans satisfying more user's needs and reduce the complexity of plan generation.

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