• Title/Summary/Keyword: run-time

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The Impact of Globalization on CO2 Emissions in Malaysia

  • CHUAH, Soo Cheng;CHEAM, Chai Li;SULAIMAN, Saliza
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.5
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    • pp.295-303
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    • 2022
  • This study investigates the impact of globalization, coal consumption, and economic growth on CO2 emissions in Malaysia by applying the Kuznets Environmental Curve model. The study employed the Autoregressive Distributed Lag modeling technique on time series data over the period of 1970-2018 to determine the short and long-run relationship between CO2 emissions and a number of variables, including globalization, coal consumption, and economic growth. The results show that globalization increase CO2 emissions in both the short and long run in Malaysia. Furthermore, the results reveal that economic growth and coal consumption degrade the environmental quality by accelerating the CO2 emissions in the short-run and long run. As a result, the findings validate the Kuznets Environmental Curve hypothesis of an inverted U-shaped relationship between economic growth and CO2 emissions in the long run for Malaysia. The findings of this study suggest that higher globalization levels and usage of coal consumption degrade the environmental quality in Malaysia. The findings also indicate the effect of economic growth on environmental degradation is positive at the initial stage but improves after the economy achieves a threshold level of income per capita in the economic development process with an inverted U-shaped pattern in the long run.

CFD Study for Wave Run-up Characteristics Around a Truncated Cylinder with Damper

  • Zhenhao Song;Bo Woo Nam
    • Journal of Ocean Engineering and Technology
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    • v.37 no.6
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    • pp.225-237
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    • 2023
  • In this study, numerical simulations for a single fixed truncated circular cylinder in regular waves were conducted to investigate the nonlinear wave run-up under various dampers and wave period conditions. The present study used the volume of fluid (VOF) technique to capture the air-water interface. The unsteady Reynolds-averaged Navier-Stokes (URANS) equation with the k- 𝜖 turbulence model was solved using the commercial computational fluid dynamics (CFD) software STAR-CCM+. First, a systematic spatial convergence study was conducted to assess the performance and precision of the present numerical wave tank. The numerical scheme was validated by comparing the numerical results of wave run-up on a bare truncated cylinder with the experimental results, and a good agreement was achieved. Then, a series of parametric studies were carried out to examine the wave run-up time series around the truncated cylinder with single and dual dampers in terms of the first- and second-order harmonic and mean set-up components. Additionally, the local wave field and the flow velocity vectors adjacent to the cylinder were evaluated. It was confirmed that under short wave conditions, the high position of the damper led to a noticeable increase in the wave run-ups with significant changes in the first- and second-order harmonic components.

A Prediction Method of Temperature Distribution on the Wafer for Real-Time Control in a Rapid Thermal Process System (실시간 제어를 위한 고속 열처리 공정에서 웨어퍼 온도 분포 추정 기법)

  • Sim, Yeong-Tae;Yi, Seok-Joo;Kim, Hagbae
    • Journal of Institute of Control, Robotics and Systems
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    • v.6 no.9
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    • pp.831-835
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    • 2000
  • The uniformity of themperature on a wafer is a wafer is one the most important parameters to conterol the RTF(Rapid Thermal Process) with proper input signals. It is impossible to achieve the uniformity of temperature without the exact estimation of temperature ar all points on the wafer. There fore, it is difficult to understand the internal dynamics as well as the structural complexities of the RTP, which is aprimary obstacle to measure the distributed temperatures on the wafer accurately. Furthermore, it is also hard to accomplish desirable estimation because only a few pyrometers are available in the general equipments. In the paper, a thermal model based on the chamber grometry of the AST SHS200 RTP system is developed to effectively control the thermal uniformity on the wafer. First of all, the estimation method of one-point measurement is developed, which is properly extended to the case of multi-point measurements. This thermal model is validated through simulation and experiments. The proposed work can be utilized to building a run-by -run or a real-time control of the RTP.

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Design and Evaluation of INS Initial Alignment under Vibration Environment of Aircraft Run-up (항공기 Run-Up 진동 환경에서의 관성항법장치 초기 정렬 방법 설계 및 평가)

  • Yu, Haesung;Lee, Inseop;Oh, JuHyun;Kim, CheonJoong;Park, Heung-won
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.7
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    • pp.691-698
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    • 2015
  • Inertial Navigation Systems (INS) are widely used as the main navigation device for aircraft. To get the initial attitude, the INS requires the initial alignment before navigation starts. An aircraft also needs an engine test procedure that causes some vibrations before flight. An INS can't be aligned in a vibration environment so the initial alignment is performed before the aircraft engine test. Therefore, the initial alignment time of an INS has been a major factor in limiting an aircraft's takeoff response time. In this paper, we designed an initial alignment algorithm that can be executed even in disturbances such as aircraft run-up. We demonstrated verification of the algorithm that is embedded on the real INS and testing methods to evaluate the alignment of the INS. We also analyzed the test results of the proposed initial alignment algorithm that is performed during a real aircraft run-up.

Proposition and Evaluation of Parallelism-Independent Scheduling Algorithms for DAGs of Tasks with Non-Uniform Execution Time

  • Kirilka Nikolova;Atusi Maeda;Sowa, Masa-Hiro
    • Proceedings of the IEEK Conference
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    • 2000.07a
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    • pp.289-293
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    • 2000
  • We propose two new algorithms for parallelism-independent scheduling. The machine code generated from the compiler using these algorithms in its scheduling phase is parallelism-independent code, executable in minimum time regardless of the number of the processors in the parallel computer. Our new algorithms have the following phases: finding the minimum number of processors on which the program can be executed in minimal time, scheduling by an heuristic algorithm for this predefined number of processors, and serialization of the parallel schedule according to the earliest start time of the tasks. At run time tasks are taken from the serialized schedule and assigned to the processor which allows the earliest start time of the task. The order of the tasks decided at compile time is not changed at run time regardless of the number of the available processors which means there is no out-of-order issue and execution. The scheduling is done predominantly at compile time and dynamic scheduling is minimized and diminished to allocation of the tasks to the processors. We evaluate the proposed algorithms by comparing them in terms of schedule length to the CP/MISF algorithm. For performance evaluation we use both randomly generated DAGs (directed acyclic graphs) and DACs representing real applications. From practical point of view, the algorithms we propose can be successfully used for scheduling programs for in-order superscalar processors and shared memory multiprocessor systems. Superscalar processors with any number of functional units can execute the parallelism-independent code in minimum time without necessity for dynamic scheduling and out-of-order issue hardware. This means that the use of our algorithms will lead to reducing the complexity of the hardware of the processors and the run-time overhead related to the dynamic scheduling.

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Design and Implementation of SR Run-Time Support System Using POSIX ZThreads (POSIX 쓰레드를 이용한 SR 실행지원시스템의 설계 및 구현)

  • Kim, Yeong-Gon;Jeong, Yeong-Pil;Park, Yang-Su;Lee, Myeong-Jun
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.4
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    • pp.1106-1120
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    • 1997
  • In this paper,we prosent a new run-time support system for SR usitn POSIX threads (Pthreads),called SR/RTS +.SR supports a rich set of concurent programming techniques with multiple cincurrency control primit-ives Since the original RTS for SR uses its own thread management facility,it should be modifide to work on different computer systems.Furthermore,the run-time efficiency of the RTS should be considered in association with those different sytems.Thus,to portability and to guarantee the predictable run-time ef-ficiency,SR/RTS + is designed on the pthreads(POSIX Threads )which supports multiple threads of con-trol within a single POSIX process.Also, the SR compiler is modified to generate the codes appropriate for pthreads interface.SR/RTS + has been develped on Spare Workstation using pthreads library announced by Florida State University and tested with the SR verification suite distribute by the University of Arizona.

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An optimal management policy for the surplus process with investments (재투자가 있는 잉여금 과정의 최적 운용정책)

  • Lim, Se-Jin;Choi, Seungkyoung;Lee, Eui-Yong
    • The Korean Journal of Applied Statistics
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    • v.29 no.7
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    • pp.1165-1172
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    • 2016
  • In this paper, a surplus process with investments is introduced. Whenever the level of the surplus reaches a target value V > 0, amount S($0{\leq}S{\leq}V$) is invested into other business. After assigning three costs to the surplus process, a reward per unit amount of the investment, a penalty of the surplus being empty and the keeping (opportunity) cost per unit amount of the surplus per unit time, we obtain the long-run average cost per unit time to manage the surplus. We prove that there exists a unique value of S minimizing the long-run average cost per unit time for a given value of V, and also that there exists a unique value of V minimizing the long-run average cost per unit time for a given value of S. These two facts show that an optimal investment policy of the surplus exists when we manage the surplus in the long-run.

A High-Speed Korean Morphological Analysis Method based on Pre-Analyzed Partial Words (부분 어절의 기분석에 기반한 고속 한국어 형태소 분석 방법)

  • Yang, Seung-Hyun;Kim, Young-Sum
    • Journal of KIISE:Software and Applications
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    • v.27 no.3
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    • pp.290-301
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    • 2000
  • Most morphological analysis methods require repetitive procedures of input character code conversion, segmentation and lemmatization of constituent morphemes, filtering of candidate results through looking up lexicons, which causes run-time inefficiency. To alleviate such problem of run-time inefficiency, many systems have introduced the notion of 'pre-analysis' of words. However, this method based on pre-analysis dictionary of surface also has a critical drawback in its practical application because the size of the dictionaries increases indefinite to cover all words. This paper hybridizes both extreme approaches methodologically to overcome the problems of the two, and presents a method of morphological analysis based on pre-analysis of partial words. Under such hybridized scheme, most computational overheads, such as segmentation and lemmatization of morphemes, are shifted to building-up processes of the pre-analysis dictionaries and the run-time dictionary look-ups are greatly reduced, so as to enhance the run-time performance of the system. Moreover, additional computing overheads such as input character code conversion can also be avoided because this method relies upon no graphemic processing.

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Removal Characteristics of Nitrogen and Phosphorus in swine wastewater by Using Acetic acid on the SBR Process (SBR에서 아세트산을 이용한 양돈폐수의 질소·인 제거 특성)

  • Huh, Mock;Kang, Jin-Young
    • Journal of the Korea Organic Resources Recycling Association
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    • v.12 no.1
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    • pp.84-93
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    • 2004
  • This study was performed : 1) to find the suitable HRT(hydralic retention time), 2) to evaluate the effects of the ratio of mixing/aeration time and injection time of external carbon source, for the removal of organics, nitrogen and phosphorus in swine wastewater by SBR(sequencing batch reactor process), which is one of the biological treatment process. The result of this study were summarized as follows : (1) As the ratio of mixing/aeration time was higher, $NH_4{^+}-N$ removal efficiency was increased and it was increased with increasing injection time of external carbon source because nitrification was affected by denitrification microbes propagation when injection time of external carbon soruce was shorted. T-N removal efficiency was increased with increasing the ratio of mixing/aeration time and injection time of external carbon source. (2) The T-P removal efficiency showed a great difference in each operating condition, and it was increased with increasing the ratio of mixing/aeration time increased and when the injection time of external carbon source was shorted because denitrification was done with effect by denitrification microbes propagation. (3) The highest removal efficiency of organic and nitrogen were obtained by the operating condition of Run 4-1(the ratio of mixing/aeration time : 16.5/5.5, injection time of external carbon source : 15hours) and T-P were obtained by the operation condition of Run 4-2(the ratio of mixing/aeration time : 16.5/5.5, injection time of external carbon source : 3hours), and efficiency(effluent concentration)of $BOD_5$, $COD_{Mn}$, $COD_{Cr}$, T-N and T-P in the treated water was 96.1%, 87.7%, 90.6%, 86.6% and 84.5%, respectively.

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AFTERMARKET PERFORMANCE OF THE U.K. IPOs

  • Lee, Ki-Hwan
    • The Korean Journal of Financial Studies
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    • v.2 no.1
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    • pp.215-244
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    • 1995
  • The purpose of this paper is to examine the three anomalies phenomena that appear in the initial public offerings(IPOs) market. Of them, the first anomaly is that the new issues are underpriced in the short-run. Secondly, the hot issue market phenomenon appears. Thirdly, in the long-run, the initial public offerings of equities are overpriced. These phenomena have been documented by Inany studies using the us stock market data. In particular, we will investigate whether these three anomalies also appear in the UK new issues market. Firstly, the underpricing phenomenon of initial public offerings in the short-run will be examined. Then the long-run performance of new issues will be examined using cross-sectional and time-series analysis. Finally, we will briefly examine the existence of the hot issue market in the uk IPOs market.

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