• 제목/요약/키워드: rate

검색결과 108,641건 처리시간 0.091초

Improved H.263+ Rate Control via Variable Frame Rate Adjustment and Hybrid I-frame Coding

  • 송환준
    • 한국통신학회논문지
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    • 제25권5A호
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    • pp.726-742
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    • 2000
  • A novel rte control algorithm consisting of two major components, i.e. a variable encoding frame rate method and a hybrid DCT/wavelet I-frame coding scheme, is proposed in this work for low bit rate video coding. Most existing rate control algorithms for low bit rate video focus on bit allocation at the macroblock level under a constant frame rate assumption. The proposed rate control algorithm is able to adjust the encoding frame rate at the expense of tolerable time-delay. Furthermore, an R-D optimized hybrid DCT/wavelet scheme is used for effective I-frame coding. The new rate-control algorithm attempts to achieve a good balance between spatial quality and temporal quality to enhance the overall human perceptual quality at low bit rates. It is demonstrated that the rate control algorithm achieves higher coding efficiency at low bit rates with a low additional computational cost. The variable frame rate method and hybrid I-frame coding scheme are compatible with the bi stream structure of H.263+.

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한국 원/달러환율과 금리의 관계분석 (Analysis about relation of Won/Dollar Foreign Exchange Rate and Interest Rate of Korea)

  • 김종권
    • 산업경영시스템학회지
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    • 제21권48호
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    • pp.133-144
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    • 1998
  • International capital movement has made progress at global liberalization of finance and foreign exchange, international monetary norm changing into floating exchange rate system, easiness of collection of information and trade at improvement of information communication technology from early of 1970's. Results of empirical test for relation between foreign exchange rate or various determination factors of foreign exchange rate and interest rate are followed by next sentences. First, according to relation between foreign exchange rate and interest rate, correlation for each of variables after OECD entrance is increased. But, long-term & short-term interest rate is affected by Hanbo & Kia's bankruptcy, continuous large scale corporates bankruptcy and crisis of foreign exchange. Therefore, financial instability is occured. If portfolio investment fund has been inflow as it is mollified by continuous shortage of foreign exchange and fall of country's credit rating, it is expected to have positive effect for long-term & short-term interest rate from appreciation of won against dollar. Second, results from relation between determination factor of foreign exchange rate and interest rate are followed by next sentences. If surplus of current account and goods account is continued, yield of corporate bond is to be stable. But, margin of surplus is expected to diminish after second quarter 98, and difference between external and domestic interest (after adjusting foreign exchange rate) is to be diminished. And if net inflows of foreign investor's fund (stock and bond) is diminished, it is to have negative effect for yield of corporate bond. According to foreign investor's investment movement of previous years, hedge fund were stayed at least during two years in Mexico. It means that sudden capital outflow is not to be happened at Korea. But if external factors from depreciation of yen and China's renminbi are instable, interest rate is expected to increase from capital's outflows. Third, if it is to decrease instability of foreign exchange rate from increase in surplus of future current account, credit rating's upwardness, stability of yen and renminbi, foreign exchange rate is expected to be stable. It is expected to have continuous stability from short-term interest rate to long-term interest rate in this empirical test.

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타액선 신티그라피 검사에서 타액선 영상과 타액 제거율의 비교 연구 (The Comparison with Salivary Image and Saliva Clearance Rate in Salivary Scintigraphy)

  • 김영빈;신규설;박연경;김건재
    • 핵의학기술
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    • 제13권1호
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    • pp.15-19
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    • 2009
  • Purpose: The aim of study is to find a correlation between Salivary clearance rate using saliva and blood and Secretion rate and Excretion rate using Salivary gland Scan images. Materials and Methods: Salivary Scan and Stimulate clearance of $^{99m}Tc$-pertechnate was performed in 20 patients with moderate function(group 1), 9 patients with severe function glands (group 2), 3 patients with non function (group 3) and normal 6 controls. Salivay clearance rate was compare with Secretion rate and Excretion rate of Salivary glands' ROI. Result: Stimulate salivary clearance of normal controls was 18.4 ml/min, salivary clearance of group 1 was 10.1 ml/min, salivary clearance of group 2 was 10.4 ml/min and salivary clearance of group 3 was 2.3 ml/min. Significant difference was found between normal controls and group 2,3 (p<0.05, p<0.05). Secretion rate and Excretion rate of normal controls was 21.6%, 24.6%, Secretion rate and Excretion rate of group 1 was 17.6%, 24.0%, Secretion rate and Excretion rate of group 2 was 8.8%, 13.9% and Secretion rate and Excretion rate of group 3 was 5.6%, 2.9%. Significant difference was found between normal controls and group 2,3 (p<0.05, p<0.05). Conclusions: Stimulate salivary clearance using saliva and blood and Secretion rate and Excretion rate using Salivary gland Scan images accord well together.

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한국 원/달러환율과 금리의 관계분석 (Analysis about relation of Won/Dollar Foreign Exchange Rate and Interest Rate of Korea)

  • 김종권
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2002년도 추계학술대회
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    • pp.305-319
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    • 2002
  • International capital movement has made progress at global liberalization of finance and foreign exchange, international monetary norm changing into floating exchange rate system, easiness of collection of information and trade at improvement of information communication technology from early of 1970's. Results of empirical test for relation between foreign exchange rate or various determination factors of foreign exchange rate and interest rate are followed by next sentences. First, according to relation between foreign exchange rate and interest rate, correlation for each of variables after OECD entrance is increased. But, long-term &short-term interest rate is affected by Hanbo & Kia's bankruptcy, continuous large scale coporates bankruptcy and crisis of foreign exchange. Therefore, financial instability is occured. If portfolio investment fund has been inflow as it is mollified by continuous shortage of foreign exchange and fall of country's credit rating, it is expected to have positive effect for long-term & short-term interest rate from appreciation of won against dollar. Second, results from relation between determination factor of foreign exchange rate and interest rate are followed by next sentences. If surplus of current account and goods account is continued, yield of corporate bond is to be stable. But, margin of surplus is expected to diminish after second quarter 98, and difference between external and domestic interest (after adjusting foreign exchange rate) is to be diminished. And if net inflows of foreign investor's fund (stock and bond) is diminished, it is to have negative effect for yield of corporate bond. According to foreign investor's investment movement of previous years, hedge md were stayed at least during two years in Mexico. It means that sudden capital outflow is not to be happened at Korea. But if external factors from depreciation of yen and China's renminbi are instable, interest rate is expected to increase from capital's outflows. Third, if it is to decrease instability of foreign exchange rate from increase in surplus of future current account, credit rating's upwardness, stability of yen and renminbi, foreign exchange rate is expected to be stable. It is expected to have continuous stability from short-term interest rate to long-term interest rate in this empirical test.

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A Survey of Rate-Adaptation Schemes for IEEE 802.11 Compliant WLANs

  • Khan, Shahbaz;Ullah, Sadiq;Ahmed, Aziz;Mahmud, Sahibzada Ali
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제7권3호
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    • pp.425-445
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    • 2013
  • The IEEE 802.11 compliant stations can transmit at multiple transmission rates. Selection of an appropriate transmission rate plays a significant role in determining the overall efficiency of a communication system. The technique which determines the channel state information and accordingly selects an appropriate transmission rate is called rate-adaptation protocol. The IEEE 802.11 standard does not provide standard specification for implementing a rate-adaptation protocol for its multi-rate capable wireless stations. Due to the lack of standard specification, there is a myriad of rate-adaptation protocols, proposed by industry and various research institutes. This paper surveys the existing rate-adaptation schemes, discusses various features which contribute significantly in the process of rate-adaptation, the timing constraints on such schemes, and the performance gains in terms of throughput, delay and energy efficiency; which can be gained by the use of rate-adaptation. The paper also discusses the implication of rate-adaptation schemes on the performance of overall communication and identifies existing research challenges in the design of rate-adaptation schemes.

우리나라 치과기공소의 연도별 증가율 및 분포현황 조사 연구 - 1990년부터 2002년까지 - (A Study on the yearly Increase ratio and The Distribution ratio of Dental Laboratories in Korea - From 1990 to 2002 -)

  • 권순석
    • 대한치과기공학회지
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    • 제25권1호
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    • pp.143-159
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    • 2003
  • In this study, the data and the Statistical Annual Report of the Korean Dental Technology Association and the yearbook of Health-Welfare Ministry from 1990 to 2002 were surveyed to study and analyze the yearly increase rate and regional distribution rate of the national dental laboratories and dental clinics, the rate of dental laboratories to dental clinics. The purpose of the thesis is to help dental technicians to open the rational and effective dental laboratory which considers the regional condition and the distribution of dental clinics. The result of the study is as follows; 1) The yearly increase rate of overall dental laboratories is 2.01 times to 2002 by the criteria of 1990. The most laboratories was increased in 1995(+94) but the least laboratories was increased in 2000(+13). According to the regional increase rate, Kyounggi Association showed the highest increase rate (7.00 times) but Woolsan Association showed the least increase rate (1.45 times) for the past 5 years. Busan Association had increased by 1.47 times by the criteria of 1990. 2) According to the regional distribution rate of dental laboratories, Seoul area showed the highest distribution rate from the minimum 26.72%(in 2002) to the maximum 35.23%(in 1990) every year, and before 1993, Busan area showed the high distribution rate of 12.49% and Daegu area 12.38%. 3) In the case of the national increase rate, dental clinics had increased by 2.01 times to 2001 by the criteria of 1990 and dental laboratories, whose number was 1,482 in 2002, had increased by 2.01 times to that year. The rate of the national dental laboratories to dental clinics went up an average of 1: 7.57 for 12 years. In 1994, the rate showed the highest 1:7.91 and in 1990, the rate showed the least 1:7.17. 4) The metropolitan rate of dental laboratories to dental clinics showed the average of 1:6.70 for 12 years, and the rate was highest in 1992(1:7.15) and the rate lowest in 1999(1:6.33). 5) The rate of dental laboratories to dental clinics in other areas was 1:9.53, the average of 12 years and was highest in 1991(1:9.97) and was lowest in 1990(1:8.79). (6) The rate of the Korean dental laboratories to dental clinics was 1:7.37 in 2001, the metropolitan rate was 1:6.53 and the rate in other areas was 1:9.10. According to the regional distribution rate, the rate of Kyounggi was highest (1:15.58) and the rate of Daegu was lowest(1:3.03).

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한국 표준어 화자의 유창성과 말속도에 관한 연구 (Fluency and Speech Rate for the Standard Korean Speakers)

  • 심홍임
    • 음성과학
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    • 제11권3호
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    • pp.193-200
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    • 2004
  • This was a preliminary study for standardizing speech rate and fluency of normal adult Korean speakers and comparing speech rate and fluency of normal speakers with those of professional speakers. The purposes of this study were to investigate (a) the speech rates (the overall speech rate and the articulation rate) and the disfluency characteristics of normnal adult speakers and (b) the speech rates (the overall speech rate and the articulation rate) and the disfluency characteristics between normal adult speakers and professional speakers. The results were as follows: The most frequent disfluency type was 'interjection' in story-telling, 'revision' in text reading and announcing of professional speakers. The professional speakers had the fastest speech rates (overall speech rate and articulation rate) among the 3 groups.

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AN ECONOMIC PRODUCTION QUANTITY INVENTORY MODEL INVOLVING FUZZY DEMAND RATE AND FUZZY DETERIORATION RATE

  • De, Sujit-Kumar;A. Goswami;P.K. Kundu
    • Journal of applied mathematics & informatics
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    • 제12권1_2호
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    • pp.251-260
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    • 2003
  • Generally, in deriving the solution of economic production quantity (EPQ) inventory model, we consider the demand rate and deterioration rate as constant quantity. But in case of real life problems, the demand rate and deterioration rate are not actually constant but slightly disturbed from their original crisp value. The motivation of this paper is to consider a more realistic EPQ inventory model with finite production rate, fuzzy demand rate and fuzzy deterioration rate. The effect of the loss in production quantity due to faulty/old machine have also been taken into consideration. The methodology to obtain the optimum value of the fuzzy total cost is derived and a numerical example is used to illustrate the computation procedure. A sensitivity analysis is also carried out to get the sensitiveness of the tolarance of different input parameters.

저주기 피로 파괴 하중하에서 AE수 변화율과 균열성장율에 관한 연구 (AE Count Rate and Crack Growth Rate under Low Cycle Fatigue Fracture Loading)

  • 이강용
    • 대한기계학회논문집
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    • 제13권2호
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    • pp.252-256
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    • 1989
  • 본 연구에서는 탄성-소성 피로파괴 시험을 하여 dN/dn과 .DELTA.J의 관계와 dN/과 da/dn의 관계에 대한 실험식을 얻고 이론적인 해석결과와 비교 검토하고자 한다.

말소리장애 아동과 일반 아동의 발화 속도와 쉼 비교 (Comparison of overall speaking rate and pause between children with speech sound disorders and typically developing children)

  • 이흥임;김수진
    • 말소리와 음성과학
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    • 제9권2호
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    • pp.111-118
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    • 2017
  • This study compares speech rate, articulatory rate, and pause between the children with mild and moderate Speech Sound Disorder (SSD) who performed Sentence Repetition Tasks and the Typically Developing children (TD) of the same chronological age. The results showed that three groups are categorized in terms of speaking rate and articulatory rate. There is no difference between the two groups with SSD children, namely between the mild and moderate groups. However, there is a significant difference in their rate of speech and the articulatory rate between the two groups, such that the two groups with SSD are significantly slower than the TD group. The results also showed that there are no significant difference in the length and frequency of pause between the moderate group and the mild group. However, there is a substantial difference between them and the TD group. This study, provided the basic data for evaluating the speech rate of the children and implies that there are limitations in speech rate among the children with SSD.