• Title/Summary/Keyword: Local Minimum

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Design of Dynamic Time Warp Element for Speech Recognition (음성인식을 위한 Dynamic Time Warp 소자의 설계)

  • 최규훈;김종민
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.3
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    • pp.543-552
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    • 1994
  • Dynamic Time Warp(DTW) needs for iterative calculations and the design of PE cell suitable for the operations is very important. Accordingly, this paper aims at real time recognition design enables large dictionary hardware realization using DTW algorithm. The DTW PE cell separated into three large blocks. "MIN" is the one block for counting accumulated minimum distance. "ADD" block calculates these minimum distances, and "ABS" seeks for the absolute values to the total sum of local distances. Circuit design and verification about the three block have been accomplished, and performed layout '||'&'||' DRC(design rule check) using 1.2 m CMOS N-Well rule base.CMOS N-Well rule base.

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The Changes of Meteorological Environment by Urban Development (대규모 도시 재개발에 따른 기상환경변화)

  • Kim, Geun-Hoi;Kim, Yeon-Hee;Koo, Hae-Jung;Kim, Kyu-Rang;Jung, Hyun-Sook
    • Atmosphere
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    • v.24 no.1
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    • pp.69-76
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    • 2014
  • Urbanization affects the local thermal environment due to the large scale land use changes. To investigate the weather environment change of large scale urban redevelopment, 9 surface temperature and humidity observations were accomplished at Eunpyeong new town area. The observation period is from March 2007 to February 2010. In the center of development area, the air temperature has increased and relative humidity has decreased, by the changes of the land cover and building construction. In the area where the green zone is maintained, air temperature and relative humidity were not changed significantly. The air temperature and relative humidity for the other development observation stations is decreased and increased, respectively. The relative temperature difference between study area and a neighboring rural location was increased during observation periods. The difference is the highest during winter. The urban-rural minimum temperature difference was increased at development area, which means that urbanization affects increasing of minimum temperature in study area.

Minimum cost design of overhead crane beam with box section strengthened by CFRP laminates

  • Kovacs, Gyorgy;Farkas, Jozsef
    • Structural Engineering and Mechanics
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    • v.61 no.4
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    • pp.475-481
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    • 2017
  • An overhead travelling crane structure of two doubly symmetric welded box beams is designed for minimum cost. The rails are placed over the inner webs of box beams. The following design constraints are considered: local buckling of web and flange plates, fatigue of the butt K weld under rail and fatigue of fillet welds joining the transverse diaphragms to the box beams, fatigue of CFRP (carbon fibre reinforced plastic) laminate, deflection constraint. For the formulation of constraints the relatively new standard for cranes EN 13001-3-1 (2010) is used. To fulfill the deflection constraint CFRP strengthening should be used. The application of CFRP materials in strengthening of steel and concrete structures are widely used in civil engineering applications due to their unique advantages. In our study, we wanted to show how the mechanical properties of traditional materials can be improved by the application of composite materials and how advanced materials and new production technologies can be applied. In the optimization the following cost parts are considered: material, assembly and welding of the steel structure, material and fabrication cost of CFRP strengthening. The optimization is performed by systematic search using a MathCAD program.

Characteristics of Seasonal Mean Diurnal Temperature Range and Their Causes over South Korea (우리나라에서 계절별 일교차의 분포 특성과 그 원인)

  • Suh, Myoung-Seok;Hong, Seong-Kun;Kang, Jeon-Ho
    • Atmosphere
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    • v.19 no.2
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    • pp.155-168
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    • 2009
  • Characteristics of seasonal mean diurnal temperature range (DTR) and their causes over South Korea are investigated using the 60 stations data of Korea Meteorological Administration from 1976 to 2005. In general, the seasonal mean DTR is greatest during spring (in inland area) and least during summer (urban and coastal area). The spatial and seasonal variations of DTR are closely linked with the land surface conditions (especially vegetation activity and soil moisture) and atmospheric conditions (cloud amount, precipitation, local circulation). The seasonal mean DTR shows a decreasing trend at the major urban areas and at the north-eastern part of South Korea. Whereas, it shows an increasing trend at the central area of the southern part. Decreasing and increasing trends of DTR are more significant during summer and fall, and during spring and winter. The decrease (increase) of DTR is mainly caused by the stronger increase of daily minimum (maximum) temperature than daily maximum (minimum) temperature. The negative effects of precipitation and cloud amount on the DTR are greater during spring and at the inland area than during winter and at the coastal area. And the effect of daytime precipitation on the DTR is greater than that of nighttime precipitation.

음성인식용 DTW PE의 IC화를 위한 ADD 및 ABS 회로의 설계

  • 정광재;문홍진;최규훈;김종교
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.15 no.8
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    • pp.648-658
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    • 1990
  • There are many methods for speed up counting in speech recongition. A multiple processing method is the one way to achieve the aim using systolic array. This arithmetic operation by the array is achieved pipelining skill. And the operation is multiprocessing by processing element(PE) that is incresing counting efficiencies. The DTW PE cell is seperated into three large blocks. "MIN" is the one block for counting accumulated minimum distance, "ADD" block calculated these minimum distances, and "ABS" seeks for the absolut values to the total sum of local distances. We have accomplished circuit design and verification about the "ADD" and "ABS" blocks, and performed total layout '||'&'||' DRC(design rule check) using 3um CMOS N-Well rule base.le check) using 3$\mu$m CMOS N-Well rule base.

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In vitro antibiotic susceptibility of field isolates of Mycoplasma hyopneumoniae and Mycoplasma hyorhinis from Korea

  • Jang, Jisung;Kim, Kiju;Park, Soyeon;Park, Bokyoung;Um, Hyungmin;Coulier, Marc;Hahn, Tae-Wook
    • Korean Journal of Veterinary Research
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    • v.56 no.2
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    • pp.109-111
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    • 2016
  • The present study was conducted to determine the antibiotic susceptibilities of local Mycoplasma hyopneumoniae (Mhp) and Mycoplasma hyorhinis (Mhr) filed isolates. Minimum inhibitory concentrations (MICs) of Mhp and Mhr field isolates (twelve each) obtained from enzootic pneumonia-like lung lesions during 2009-2011 from Korea were determined using the broth microdilution method. Tylvalosin showed the highest activity against Mhp and Mhr field isolates, with $MIC_{90}$ values of $0.06{\mu}g/mL$ and $0.12{\mu}g/mL$, respectively. Therefore, Korean Mhp and Mhr isolates are highly susceptible to tylvalosin.

Successive Backward Sweep Method for Orbit Transfer Augmented with Homotopy Algorithm (호모토피 알고리즘을 이용한 Successive Backward Sweep 최적제어 알고리즘 설계 및 궤도전이 문제에의 적용)

  • Cho, Donghyurn;Kim, Seung Pil
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.44 no.7
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    • pp.620-628
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    • 2016
  • The homotopy algorithm provides a robust method for determining optimal control, in some cases the global minimum solution, as a continuation parameter is varied gradually to regulate the contributions of the nonlinear terms. In this paper, the Successive Backward Sweep (SBS) method, which is insensitive to initial guess, augmented with a homotopy algorithm is suggested. This approach is effective for highly nonlinear problems such as low-thrust trajectory optimization. Often, these highly nonlinear problems have multiple local minima. In this case, the SBS-homotopy method enables one to steadily seek a global minimum.

ELIMINATION OF BIAS IN THE IIR LMS ALGORITHM (IIR LMS 알고리즘에서의 바이어스 제거)

  • Nam, Seung-Hyon;Kim, Yong-Hoh
    • The Journal of Natural Sciences
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    • v.8 no.1
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    • pp.5-15
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    • 1995
  • The equation error formulation in the adaptive IIR filtering provides convergence to a global minimum regardless a local minimum with a large stability margin. However, the equation error formulation suffers from the bias in the coefficient estimates. In this paper, a new algorithm, which does not require a prespecification of the noise variance, is proposed for the equation error formulation. This algorithm is based on the equation error smoothing and provides an unbiased parameter estimate in the presence of white noise. Through simulations, it is demonstrated that the algorithm eliminates the bias in the parameter estimate while retaining good properties of the equation error formulation such as fast convergence speed and the large stability margin.

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Optimum Design of the Power Yacht Based on Micro-Genetic Algorithm

  • Park, Joo-Shin;Kim, Yun-Young
    • Journal of Navigation and Port Research
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    • v.33 no.9
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    • pp.635-644
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    • 2009
  • The optimum design of power yacht belongs to the nonlinear constrained optimization problems. The determination of scantlings for the bow structure is a very important issue with in the whole structural design process. The derived design results are obtained by the use of real-coded micro-genetic algorithm including evaluation from Lloyd's Register small craft guideline, so that the nominal limiting stress requirement can be satisfied. In this study, the minimum volume design of bow structure on the power yacht was carried out based on the finite element analysis. The target model for optimum design and local structural analysis is the bow structure of a power yacht. The volume of bow structure and the main dimensions of structural members are chosen as an objective function and design variable, respectively. During optimization procedure, finite element analysis was performed to determine the constraint parameters at each iteration step of the optimization loop. optimization results were compared with a pre-existing design and it was possible to reduce approximately 19 percents of the total steel volume of bow structure from the previous design for the power yacht.

On-line Vector Quantizer Design Using Simulated Annealing Method (Simulated Annealing 방법을 이용한 온라인 벡터 양자화기 설계)

  • Song, Geun-Bae;Lee, Haeng-Se
    • The KIPS Transactions:PartB
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    • v.8B no.4
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    • pp.343-350
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    • 2001
  • 백터 양자화기 설계는 다차원의 목적함수를 최소화하는 학습 알고리즘을 필요로 한다. 일반화된 Lloyd 방법(GLA)은 벡터 양자화기 설계를 위해 오늘날 가장 널리 사용되는 알고리즘이다. GLA 는 일괄처리(batch) 방식으로 코드북을 생성하며 목적함수를 단조 감소시키는 강하법(descent algorithm)의 일종이다. 한편 Kohonen 학습법(KLA)은 학습벡터가 입력되는 동안 코드북이 갱신되는 온라인 벡터 양자화기 설계 알고리즘 이다. KLA는 원래 신경망 학습을 위해 Kohonen에 의해 제안되었다. KLA 역시 GLA와 마찬가지로 강하법의 일종이라 할 수 있다. 따라서 이들 두 알고리즘은, 비록 사용하기 편리하고 안정적으로 동작을 하지만, 극소(local minimum) 점으로 수렴하는 문제를 안고 있다. 우리는 이 문제와 관련하여 simulated annealing(SA) 방법의 응용을 논하고자 한다. SA는 현재까지 극소에 빠지지 않고 최소(global minimum)로 수렴하면서, 해의 수렴이 (통계적으로) 보장되는 유일한 방법이라 할 수 있다. 우리는 먼저 GLA에 SA를 응용한 그 동안의 연구를 개괄한다. 다음으로 온라인 방식의 벡터 양자화가 설계에 SA 방법을 응용함으로써 SA 방법에 기초한 새로운 온라인 학습 알고리즘을 제안한다. 우리는 이 알고리즘을 OLVQ-SA 알고리즘이라 부르기로 한다. 가우스-마코프 소스와 음성데이터에 대한 벡터양자화 실험 결과 제안된 방법이 KLA 보다 일관되게 우수한 코드북을 생성함을 보인다.

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