• 제목/요약/키워드: Mixed low

검색결과 2,712건 처리시간 0.031초

Improved Excitation Modeling for Low-Rate CELP Speech Coding

  • Kwon, Chul-Hong
    • The Journal of the Acoustical Society of Korea
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    • 제18권2E호
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    • pp.24-30
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    • 1999
  • In this paper, we propose a weighting dependent mixed source model (WD-MSM) coder that is an improved version of a CELP-based mixed source model (C-MSM) coder. The coder classifies speech segments into three types : voiced, unvoiced and mixed. The excitation for a voiced frame is an adaptive source, and the excitation for an unvoiced frame is a stochastic source. The coder has a modified mixed source for a mixed frame. We apply different weighting functions for three classes. Simulation results show that the proposed coder at 4 kbits/s yields very good performance both subjectively and objectively.

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신제품개발전략의 유형과 성과에 관한 연구 (A Study on the Relationship between New Product Development Strategies and New Product Outcomes)

  • 김지대;김기영
    • 한국경영과학회지
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    • 제21권3호
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    • pp.11-46
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    • 1996
  • The objectives of this research paper are to identify the types of the firm's new product development strategy and their characteristics about business strategy, to examine the effect of each type on new product outcomes, and to explore the contingency variable influencing the relationship between these types and new product outcomes. The result of the research are summarized as follows : First, in terms of both the resource allocation for product innovativeness and technology acquisition method, this study suggests 9 types of the firm's new product development strategies- Type 1 (pursuing low innovative products/relying on external technology), Type 2 (pursuing low innovative products oriented/relying on internal technology), Type 3 (pursuing low innovative products/relying on mixed technology), Type 4 (pursuing high innovative products/relying on internal technology), Type 6(pursuing high innovative products /relying on mixed technology), Type 7 (balancing low and high innovative products/relying on external technology), Type 8 (balancing low and high innovative products/relying on internal technology), Type 9 (balancing low and high innovative products/relying on mixed technology). Second, these 9 types are deeply associated with the firm's business strategic variables such as product differentiation and market differentiation, and exhibit different level of both technical and commercial performance of new products. Finally, the effects of these types on new product outcomes are different according to industrial environment and firms' characteristics with respect to size and technological capability.

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대체연료로서 가솔린-메타놀 혼합연료에 의한 가솔린 기관성능과 배출오염물에 관한 연구 (A study on engine performances and exhaust emissions using gasoline-methanol as an alternative fuel)

  • 김희철;용기중
    • 오토저널
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    • 제3권2호
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    • pp.18-26
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    • 1981
  • The purpose of this paper is to study the possibility of practical use of gasoline-methanol mixed fuel as an alternative fuel of gasoline engines in the light of engine performances and harmful exhaust emissions as well as mixings and separations of the mixed fuels. When the methanol of 99.8% purity is mixed with super or regular gasoline available on the market today, the experimental results obtained without modifying carburetor in this study are as follows; 1.The separation ratio depends upon the gasoline-methanol mixing ratio only, regardless of fuel temperature and fuel additives for preventing separation of phase. 2.The critical absorption ratio is affected by the gasoline-methanol mixing ratio, its temperature and the quantity of fuel additives. 3.Concerning the distillation temperature, the initial point of all sorts of fuels is almost same,but 10% point and 35-60% point of mixed fuels are lower than those of gasoline only. 4.In case of throttle valve opening set, engine output using the mixed fuels is decreased compared to gasoline, but thermal efficiency is increased as a consequence of decreasing specific energy consumption. 5.In case of fixed load test, thermal efficiency is increased at low engine speed even under low part-load as well as under comparatively high part-load including full load. 6.CO and NOx emissions are reduced remarkably with the mixed fuels.

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$CO_2$ 용접의 스패터 발생에 미치는 용적이행 모드의 영향 (Effect of Metal Transfer Mode on Spatter Generation of $CO_2$ Welding)

  • 강봉용;김희진
    • Journal of Welding and Joining
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    • 제15권2호
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    • pp.72-80
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    • 1997
  • The spatter generation rate of GMA welding with $CO_2$ gas shielding was measured with the change of welding conditions such as wire feeding rate and welding voltage and then the results were analized with the accompanying changes in metal transfer mode and in bead geometry. The spatter generation rate (SGR) was relatively low not only wit the short circuit transfer but with the truely globular transfer mode. However, the SGR resulted with the mixed mode were consistantly high. The resultant wave pattern of mixed mode was due to the coexistance of short-circuit and globular transfer and characterized by the frequent appearance of instantaneous short circuit. Considering the result of SGR and that of bead geometry, it could be concluded that when the wire feeding rate (or welding current) was either low or high, the optimum bead shape could be obtained along with the low spatter generation. However, in the middle range of wire feeding rate, the optimum bead shape was only obtained in the mixed mode condition resulting in the high spatter generation.

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저소득층 아동을 위한 혼합연령 방과후 프로그램 개발 연구: 정서지능 발달을 중심으로 (Development of the Mixed-Age After School Program for Low SES Children: Focused on Facilitation of Emotional Intelligence)

  • 이영자;이종숙;이옥;신은수;이정욱
    • 아동학회지
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    • 제20권4호
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    • pp.3-24
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    • 1999
  • The present study researched the development of a mixed-age after school program with a focus on the facilitation of emotional intelligence for low SES children. The model program was based on the Mayer and Salovey (1997) theory of emotional intelligence. Activities for 17 sessions were constructed on the basis of 43 objectives. The program was implemented with 53 children in the after school program classes of one elementary school in Kyuggi Province for 6 months. Participants were from low SES families, grouped into 3 mixed-age (K-3rd grade level) classes. Evaluation of the program showed positive effects on the development of children's emotional intelligence. Validity and appropriateness were discussed.

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High-throughput Low-complexity Mixed-radix FFT Processor using a Dual-path Shared Complex Constant Multiplier

  • Nguyen, Tram Thi Bao;Lee, Hanho
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제17권1호
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    • pp.101-109
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    • 2017
  • This paper presents a high-throughput low-complexity 512-point eight-parallel mixed-radix multipath delay feedback (MDF) fast Fourier transform (FFT) processor architecture for orthogonal frequency division multiplexing (OFDM) applications. To decrease the number of twiddle factor (TF) multiplications, a mixed-radix $2^4/2^3$ FFT algorithm is adopted. Moreover, a dual-path shared canonical signed digit (CSD) complex constant multiplier using a multi-layer scheme is proposed for reducing the hardware complexity of the TF multiplication. The proposed FFT processor is implemented using TSMC 90-nm CMOS technology. The synthesis results demonstrate that the proposed FFT processor can lead to a 16% reduction in hardware complexity and higher throughput compared to conventional architectures.

수평 사각채널 내 저 레놀즈수 혼합대류 유동의 3차원 수치해석 (3-D Numerical Analysis on a low Reynolds Number Mixed Convection in a Horizontal Rectangular Channel)

  • 박일용;배대석
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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    • pp.210-215
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    • 2005
  • A three-dimensional numerical simulation is performed to investigate on a low Reynolds number mixed convection in a horizontal rectangular channel with the upper part cooled and the lower part heated uniformly. The three-dimensional governing equations are solved using a finite volume method. For convective term, the central differencing scheme is used and for the pressure correction, the PISO algorithm is used. Solutions are obtained for A=4, Pr=0.72, 10, 909, the Reynolds number ranging from $2.1{\times}10^{-2}$ to $1.2{\times}10^{-1}$, the Rayleigh number is $3.5{\times}10^4$. It is found that vortex roll structures of mixed convection in horizontal rectangular channel can be classified into three roll structures which affected by Prandtl number and Reynolds number.

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섬유를 혼입한 초고성능콘크리트용 프리믹스결합재의 유동성 및 강도 특성 (Flowability and Strength Properties on Ultra High Performance Concrete Pre-mixed Binders with Fiber)

  • 구경모;황인성;권오봉
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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    • pp.204-205
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    • 2017
  • In this study, flowability and strength on ultra high performance concrete(UHPC) pre-mixed binders with fiber was investigated. The flow of UHPC with pre-mixed binders was higher than that of seperate mixing conditions. The UHPC using PVA fiber with high specific surface area showed a low flow compared to steel fiber. An pre-mixing method led to improved strength of UHPC and low deviation of specimens due to dispersion effect of each materials.

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단련한 흰쥐의 속근 및 지근에 Glycogen 과저장이 운동 지구력에 미치는 영향 (Effects of Glycogen Supercompensation in Fast and Slow Muscles on Maximal Running Time of Endurance-trained Rats)

  • 연동수;황수관;김인숙;고성경;남택상;강두희
    • The Korean Journal of Physiology
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    • 제22권1호
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    • pp.63-77
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    • 1988
  • This study was carried out to investigate relationships between maximal running time (MRT) and glycogen supercompensation in fast twitch white fibers (white vastus, WV), fast twitch red fibers (red vastus, RV) and slow twitch red fibers (soleus muscle, SM) of endurance-trained rats. Male rats of a Sprague-Dawley strain were divided into the trained groups and untrained groups. Untrained groups were acquired to run on the treadmill 10 minutes for 3 days and remained rest and maintained with mixed diet for 4 weeks. For last 10 days of resting period, the untrained rats were divided into 3 groups i.e. mixed diet (untrained control), high and low carbohydrate (CHO) diet groups. And each group was subdivided into 2 groups, one group was tested for the MRT and the other was sacrificed to measure the blood glucose, blood lactate, glycogen contents of liver and muscles. The experimental groups were trained on treadmill by a modified method of Constable et al. (1984) maintained with mixed diet for 4 weeks. After measurement of MRT of this group, they were also divided into high and low CHO groups and fed with these diet for 2 days and MRT of each group was measured again to see the effect of high or low CHO feeding on the MRT. Each group was maintained with the same diet for next 2 days during which some of the rats were sacrificed at given time intervals for the measurements of blood glucose and lactate, liver and the muscles glycogen. The results were summarized as follows; 1) In the untrained group, there were no significant differences between subgroups in MRT, glycogen conent of SM, RV and WV. But blood glucose concentration and glycogen content of liver of low CHO group were significantly lower than those of mixed diet group. 2) The MRT and glycogen content of SM, RV and WV of trained mixed diet group were significantly increased compared to those of untrained mixed diet group, but there was no significant difference in glycogen content of liver. 3) MRT of trained mixed, high CHO and low CHO groups were $137{\pm}9.8,\;176{\pm}9.8\;and\;129{\pm}7.3\;min$ respectively with the significant difference between them. 4) There were no differences in blood lactate concentrations between the trained high and low CHO groups immediately after maximal running and during recovery period. 5) Glycogen contents in RV and SM of trained high CHO group were significantly increased, and glycogen contents in RV, WV and liver of trained low CHO group were significantly decreased compared to those of trained mixed diet group. 6) Immediately after maximal running, the blood glucose concentrations of trained high CHO and low CHO groups were $73{\pm}4.0\;and\;67{\pm}6.9mg%$ respecitively. The blood glucose of the trained high CHO group was fully recovered within one hour by feeding. But blood glucose concentration of low CHO group was slowly recovered up to $114{\pm}4.1mg%$ after two hours of feeding and maintained. Those values were still significantly lower than that of trained mixed diet group. The synthetic rates of glycogen in liver and muscles during the recovery period followed the similar time course of the blood glucose recoveries in each group. These results suggest that an increase in MRT of trained high CHO group was attributed to the glycogen supercompensation in slow twitch muscle fibers. And a decrease in MRT of trained low CHO may be due to decreased glycogen contents of liver and muscles. The results also suggest that glycogen supercompensation was more evident in slow twitch red fibers of endurance-trained rats and blood glucose is one of the limiting factors of glycogen synthesis.

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복합금속비누와 안정화조제를 이용한 PVC의 열안정화에 대한 연구 (Study of thermal stability on PVC using mixed metal soap and stabilizer)

  • 전인기;안성환;정광보
    • 한국응용과학기술학회지
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    • 제27권4호
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    • pp.552-558
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    • 2010
  • Zinc soap and Zn/Ba mixed metal soap were synthesized and PVC plastisol with mixed metal soap and various costabilizers were also synthesized with good structures and characterized by IR and $^1H$-NMR. The IR spectrums and $^1H$-NMR spectrums of the synthesized soaps were in very good accordance with the structures proposed by earlier workers. In using phosphite as a costabilizer, TIDP phosphite was shown to be the excellent thermal stabilization effect at the low temperature and TNPP phosphite was shown to be the excellent thermal stabilization effect at the high temperature. In case of antioxidant, it was revealed that antioxidant was not effective in the low temperature thermal stabilization effect while highly effective in the high temperature thermal stability. $NaClO_4$ solution with sorbitol solvent had the best thermal stabilization effect among $NaClO_4$ solution series at low and high temperature.