• 제목/요약/키워드: Cycle pattern

검색결과 752건 처리시간 0.03초

Reduction of the Refrigerant-Induced Noise from the Transition of Flow Pattern by Decreasing Tube Diameter

  • Takushima, Akira;Han, Hyung-Suk;Jung, Wei-Bong
    • International Journal of Air-Conditioning and Refrigeration
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    • 제17권2호
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    • pp.37-44
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    • 2009
  • It is well known that a refrigerant-induced noise is caused by two-phase flow in the indoor unit of a heat pump air-conditioner. Especially when the flow pattern in a pipe is intermittent flow, the irregular noise occurs frequently. But it is very difficult to avoid this kind of the noise for the application of air-conditioner. Therefore, in this research, the flow patterns at two-phase flow state in a pipe of the indoor unit for the air-conditioner are researched using cycle simulator at typical cycle conditions. In order to find the relationship between refrigerant-induced noise and flow pattern, the noise patterns are investigated with respect to the estimated flow pattern from the various flow pattern maps. Base on the estimations of the flow patterns by those maps, the refrigerant-induced noise is evaluated as decreasing tube diameter, which can transit the flow pattern from slug to annular flow.

군 운용 지역에서 차량의 주행 패턴에 따른 주행모드 개발 (Development of a Vehicle Driving Cycle in a Military Operational Area Based on the Driving Pattern)

  • 최낙원;한동식;조승완;조성래;양진생;김광석;장영준;전충환
    • 한국자동차공학회논문집
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    • 제20권4호
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    • pp.60-67
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    • 2012
  • Most of a driving cycle is used to measure fuel consumption (FC) and emissions for a specified vehicle. A driving cycle was reflected geography and traffic characteristics for each country, also, driving pattern is affected these parameters such as vehicle dynamics, FC and emissions. Therefore, this study is an attempt to develop a driving cycle for military operational area. The proposed methodology the driving cycle using micro-trips extracted from real-world data. The methodology is that the driving cycle is constructed considering important parameters to be affected FC. Therefore, this approach is expected to be a better representation of heterogeneous traffic behavior. The driving cycle for the military operational area is constructed using the proposed methodology and is compared with real-world driving data. The running time and total distance of the final cycle is 1461 s, 13.10 km. The average velocity is 32.25 km/h and average grade is 0.43%. The Fuel economy in the final cycle is 5.93 km/l, as opposed to 6.10 km/l for real-world driving. There were about 3% differences in driving pattern between the final driving cycle and real-world driving.

지역 교통망 관리를 위한 최적 신호순서에 관한 연구 (A Study on the Optimal Signal Timing for Area Traffic Control)

    • 한국경영과학회지
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    • 제24권2호
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    • pp.69-80
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    • 1999
  • A genetic algorithm to determine the optimal signal sequence and double cycle pattern is described. The signal sequence and double cycle pattern are used as the input for TRANSYT to find optimal signal timing at each junction in the area traffic networks, In the genetic process, the partially matched crossover and simple crossover operators are used for evolution of signal sequence and double cycle pattern respectively. A special conversion algorithm is devised to convert the signal sequence into the link-stage assignment for TRANSYT. Results from tests using data from an area traffic network in Leicester region R are given.

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주가지수 파생상품 Life Cycle과 투자자 유형별 거래행태 (Life Cycle of Index Derivatives and Trading Behavior by Investor Types)

  • 오승현;한상범
    • 재무관리연구
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    • 제25권2호
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    • pp.165-190
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    • 2008
  • 선물 및 옵션의 만기결제와 관련된 정보비대칭 상황은 각 투자자 집단의 거래활동에 가시적인 영향을 줄 수 있다. 이러한 가능성을 조사하기 위해서 본 연구는 만기일을 제외한 파생상품의 life cycle을 시간의 경과에 따라 3개의 구간으로 설정한 후, 각 투자자 유형의 거래활동이 각 구간별로 보이는 변화 패턴을 조사하였다. 조사된 KOSPI200 지수 파생상품시장의 투자자 유형별 거래행태는 Foster and Viswanathan(1990)의 전략적 유동성 거래자 모형을 통해서 해석되었다. 한편, 투자자 유형별로 KOSPI200 지수 파생상품의 만기결제와 관련된 정보우위성을 측정 및 비교함으로써 정보비대칭 정도 및 정보거래자의 확인(identification) 문제에 조금 더 접근할 수 있었다. 본 연구의 주요 결과는 다음과 같이 요약된다. 첫째, 투자자 집단의 거래활동은 KOSPI200 지수 파생상품의 life cycle에 따라 3가지 유형(ㄱ자형, L자형, U자형)의 패턴으로 요약된다. ㄱ자형은 만기일 이전 1주일 동안 거래활동을 축소하는 패턴이고, L자형은 만기일 이후 1주일 동안 거래활동을 확대하는 패턴이고, U자형은 만기일 이전 1주일과 만기일 이후 1주일 동안 거래활동을 확대하는 패턴이다. 둘째, 개인투자자는 파생상품 life cycle과 관련하여 대형주 종목군을 대상으로 ㄱ자형 거래패턴(선물만기 기준)과 U자형 거래패턴(옵션 단독만기 기준)을 보인다. 이러한 거래패턴은 Foster and Viswanathan(1990)의 전략적 유동성 거래자 모형의 예상과 일치하였다. 셋째, 파생상품 life cycle과 관련하여 외국인투자자의 거래행태는 부분적으로 전략적 유동성 거래자 모형의 예상과 일치하였으나, 기관투자자의 거래행태는 전략적 유동성 거래자 모형의 예상과 무관하였다. 우리나라 주식시장의 전체 거래규모에서 가장 큰 비중을 차지하는 개인투자자가 파생상품의 만기와 관련하여 전략적으로 유동성 거래를 수행한다는 점은 파생상품의 life cycle이 주식시장에 주기적으로 영향을 주는 중요한 경로임을 의미한다. 본 연구는 이러한 경로를 새로이 규명하였다는 점에서 의미를 가진다.

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Electromagnetism Mechanism for Enhancing the Refueling Cycle Length of a WWER-1000

  • Poursalehi, Navid;Nejati-Zadeh, Mostafa;Minuchehr, Abdolhamid
    • Nuclear Engineering and Technology
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    • 제49권1호
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    • pp.43-53
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    • 2017
  • Increasing the operation cycle length can be an important goal in the fuel reload design of a nuclear reactor core. In this research paper, a new optimization approach, electromagnetism mechanism (EM), is applied to the fuel arrangement design of the Bushehr WWER-1000 core. For this purpose, a neutronic solver has been developed for calculating the required parameters during the reload cycle of the reactor. In this package, two modules have been linked, including PARCS v2.7 and WIMS-5B codes, integrated in a solver for using in the fuel arrangement optimization operation. The first results of the prepared package, along with the cycle for the original pattern of Bushehr WWER-1000, are compared and verified according to the Final Safety Analysis Report and then the results of exploited EM linked with Purdue Advanced Reactor Core Simulator (PARCS) and Winfrith Improved Multigroup Scheme (WIMS) codes are reported for the loading pattern optimization. Totally, the numerical results of our loading pattern optimization indicate the power of the EM for this problem and also show the effective improvement of desired parameters for the gained semi-optimized core pattern in comparison to the designer scheme.

택트타임, 피치타임, 사이클타임의 이해와 적용방안 (Understanding and Implementation Strategy of Tact Time, Pitch Time and Cycle Time)

  • 최성운
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2011년도 추계학술대회
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    • pp.557-561
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    • 2011
  • The study proposes three types of production lead time according to the production or demand pattern. First of all, it discusses the difference of three lead times. While pitch time and cycle time are used in push system with process stock and mass conveyor production, the tact time is used in pull system like as JIT based lean production system.

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Cell Cycle-dependent Expression of Chitin Synthase Genes in Aspergillus nidulans

  • Park, Bum-Chan;Maeng, Pil-Jae;Park, Hee-Moon
    • Journal of Microbiology
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    • 제39권1호
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    • pp.74-78
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    • 2001
  • The transcription of the chitin synthase genes (chss) was cell cycle-regulated in Aspergillus nidulans and the expression pattern was classified into two groups. Group one, containing chsA and chsC, showed decreasing transcription level upon entry into the S-phase and no further variation during the remainder of the cell cycle. However, group two, containing chsB, chsD, and csmA showed a sharp decrease of mRNA level upon entry into the G2-phase and an increase during the M-phase. Our results suggested that the chss, belonging to same group with the similar expression pattern during the cell cycle are functionally linked and that chsD may play a role in hyphal growth and development in A. nidulans.

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Expression of Replication-Independent Chicken H3.3 Histone Gene without Introns

  • Son, Seung-Yeol;Hong, Bum-Shik
    • BMB Reports
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    • 제30권3호
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    • pp.200-204
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    • 1997
  • We eliminated introns from replication independent chicken H3.3 histone gene using a H3.3 cDNA clone and a genomic H3.3 clone. After introduction into Rat 3 cells, we observed its pattern of expression by analyzing mRNA from different phases of the cell cycle. Even without introns, the H3.3 gene was expressed constitutively at a low level throughout the cell cycle. This indicates that the introns in the H3.3 gene are not responsible for the cell cycle-independent expression of the gene. This result contradicts previous reports that suggested their importance in cell cycle regulated expression. We believe that other regions of the gene, promoter, coding region, and/or 3'-end of the gene, are involved in its expression pattern.

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Role of the Promoter Region of a Chicken H3 Histone Gene in Its Cell Cycle Dependent Expression

  • Son, Seung-Yeol
    • BMB Reports
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    • 제32권4호
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    • pp.345-349
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    • 1999
  • We fused the promoter region of an H3.2 chicken histone gene, whose expression is dependent on the cell cycle, to the 5' coding region of an H3.3 chicken histone gene, which is expressed constitutively at a low level throughout the cell cycle. This fusion gene showed a cell cycle-regulated pattern of expression, but in a different manner. The mRNA level of the fusion gene increase during the S phase of the cell cycle by about 3.7-fold at 6 h and 2.7-fold at 12 h after the serum stimulation. The mRNA level of the intact H3.2 gene, however, increased by an average of 3.6-fold at 6 h and 8.7-fold at 12 h. This different expression pattern might be due to the differences in their 3' end region that is responsible for mRNA stability. The 3' end of the H3.2 mRNA contains a stem-loop structure, instead of a poly(A) tail present in the H3.3 mRNA. We also constructed a similar fusion gene using a H3.3 histone gene whose introns had been eliminated to rule out the possibility of involvement of the introns in cell cycle-regulated expression. The expression of this fusion gene was almost identical to the fusion gene made previously. These results indicate that the promoter region of the H3.2 gene is only partially responsible for its expression during the S phase of the cell cycle.

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『상한론(傷寒論)』 변병진단체계(辨病診斷體系)에 근거하여 마황행인감초석고탕(麻黃杏仁甘草石膏湯) 투여 후 호전된 증례 2례 고찰 (Two Case Reports treated by Mahwang-Haeangin-Gamcho-Seokgo-tang based on Shanghanlun Provisions)

  • 하현이;윤효중;이성준
    • 대한상한금궤의학회지
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    • 제8권1호
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    • pp.67-85
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    • 2016
  • Objectives: In this paper, two cases which showed the meaningful results on the patients' chief complaints were analyzed. The patients were treated with the Mahwang-Haengin-Gamcho-seokgo-tang herbal medication based on Shanghanlun disease pattern identification diagnostic system. Methods: The patients were diagnosed based on Shanghanlun, disease pattern identification diagnostic system. In case 1, the change of menstruation cycle was noted and pre-menstrual discomforts were measured with Menstrual Distress Questionnaire(MDQ). In case 2, Quality of life questionnaire for adult Korean asthmatics (QLQAKA) was used to estimate the quality of the patient's life. Results: All the symptoms were improved after the Mahwang-Haengin-Gamcho-seokgotang treatment. In case 1, the menstruation cycle decreased to 30 days average. MDQ score decreased 143 to 103. In case 2, the change of the QLQAKA score as 1.647 average point is considered as a meaningful improvement. Conclusion: With great difference to a 'Symptom-Medicine' diagnostic system, the disease pattern identification diagnostic system seeks the pathologic pattern through the patient's whole life. More studies and multiple cases based on the diagnostic system are needed to prove this possibility later.