• Title/Summary/Keyword: Busy period

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TWO-CLASS M/PH,G/1 QUEUE WITH IMPATIENCE OF HIGH-PRIORITY CUSTOMERS

  • Kim, Jeongsim
    • Journal of applied mathematics & informatics
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    • v.30 no.5_6
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    • pp.749-757
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    • 2012
  • We consider the M/PH,G/1 queue with two classes of customers in which class-1 customers have deterministic impatience time and have preemptive priority over class-2 customers who are assumed to be infinitely patient. The service times of class-1 and class-2 customers have a phase-type distribution and a general distribution, respectively. We obtain performance measures of class-2 customers such as the queue length distribution, the waiting time distribution and the sojourn time distribution, by analyzing the busy period of class-1 customers. We also compute the moments of the queue length and the waiting and sojourn times.

Analysis of $M^{X}/G/1$ and $GEO^{X}/G/1$ Queues with Random Number of Vacations (임의의 횟수의 휴가를 갖는 $M^{X}/G/1$$GEO^{X}/G/1$ 대기행렬의 분석)

  • 채경철;김남기;이호우
    • Journal of the Korean Operations Research and Management Science Society
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    • v.27 no.2
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    • pp.51-61
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    • 2002
  • By using the arrival time approach of Chae et at. [6], we derive various performance measures including the queue length distributions (in PGFs) and the waiting time distributions (in LST and PGF) for both M$^{x}$ /G/1 and Geo$^{x}$ /G/1 queueing systems, both under the assumption that the server, when it becomes idle, takes multiple vacations up to a random maximum number. This is an extension of both Choudhury[7] and Zhang and Tian [11]. A few mistakes in Zhang and Tian are corrected and meaningful interpretations are supplemented.

Performance Analysis of a Parallel System Having a Cold Standby Unit

  • Sharma, S.C.;Bae, S.;Baek, J.B.;Singh, K.P.
    • International Journal of Reliability and Applications
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    • v.8 no.1
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    • pp.67-82
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    • 2007
  • This paper deals with the effectiveness analysis of an engineering system, which has two units of different strengths in parallel and one unit as a cold standby unit. Failure times for all the units have negative exponential distribution whereas their repair times have general distribution. Single server caters the need for the system. The effectiveness analysis of the system is done by using regenerative point technique. The different measures of effectiveness such as mean sojourn time, mean time to system failure, availability, busy period, etc, are derived. Cost factors also taken into consideration.

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Paradigm Shift in GNSS Education for Asia Pacific Nations

  • Hassan, Azmi;Subari, Mustafa Din
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.2
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    • pp.377-381
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    • 2006
  • This paper identifies GNSS education and training program under Geomatic field of study. GNSS education programs is evaluated $vis-{\grave{a}}-vis$ new-products. Data on Geomatic knowledge generation in the era of the GNSS derivatives over the 1975 - 2003 period are examined. The emerging trends and patterns; in particular for selected Asian nations will be dissected in detail. The knowledge indicator used in this study is the patent ownership against the background of emergence of new core technologies and innovations in the field of GNSS. Looking at the dismal performance of Geomatic professionals in terms of innovative activities in most part of Asian and Malaysia in particular, is it there is something that holding up these professionals from doing so? With our universities and numerous polytechnics offering Geomatic program, more is expected from them. Is it a problem of lack or inadequacy of skills? Or is it these professionals are too busy and being narrowly focused on doing something else?

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A Case Analysis on the Time Management of the HwaSung Construction Project in Choseon Dynasty (조선시대 화성성역의 공정관리 사례분석)

  • Kim, Kyoon-Tai
    • Journal of the Korea Institute of Building Construction
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    • v.8 no.6
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    • pp.139-145
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    • 2008
  • The objective of this paper is to analyze the construction management capacity of Choseon Dynasty and suggest a new interpretation on the construction capacity of the time management by reviewing the time management case during a representative construction project, HwaSungk construction project implemented in the latter period of Choseon Dynasty around 200 years ago. which was described in HwaSungSungYoukEuGye. The analysis results of the time management capacity during the latter period of Choseon Dynasty depicted in the HwaSungSungYoukEuGye is summarized as follows: (1) It took 2 years and 6 months to complete the Hwasung construction project. However, all of the single buildings were constructed within 6 months, a relatively short period of time. Judging from the fact, it can be assumed that the construction techniques using wood of the time were very sophisticated. (2) When the HwaSung was constructed, it took a relatively short period of time to complete works from placing the foundation to erecting columns and to placing a crossbeam on the columns. Based on the fact, it can be also inferred that assembly processing techniques of the time were also sophisticated and the level of member processing and assembling techniques of the time was considerably good as well. (3) The HwaSung construction was continued throughout the year without any influence by weather conditions, which tells us that division of labor by work was performed, and it was possible to mobilize labor force for the construction project even during the busy farming seasons.

The Energy Performance Analysis Between Synchronous and Asynchronous Duty Cycle based MAC Protocols in Wireless Sensor Networks (무선 센서네트워크 환경에서 Duty Cycle 기반 동기식 및 비동기식 MAC 프로토콜의 에너지 성능과 지연시간에 대한 상호 분석)

  • Lee, Jae-Ho;Eom, Doo-Seop
    • Journal of Information Technology Services
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    • v.10 no.3
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    • pp.237-250
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    • 2011
  • Recently, Wireless Sensor Networks (WSN) require energy performance and guaranteed delivery delay time, contrarily with previous MAC protocols that aim to high throughput mostly. In order to satisfy the new significant requirements, many MAC protocols of WSN employ and try to enhance the duty cycle mechanism which is energy efficient technique in MAC layer. This duty cycle mechanism is oriented by toggling the transceiver conditions composed of wakeup and sleep states. The synchronous MAC protocols perform the period synchronization process. Hence, these are energy efficient in periodic monitoring environment, but are inefficient in where an event is incurred rarely and infrequently. Otherwise, the performance of asynchronous MAC protocols are contrarily with synchronous protocols. In this paper, we design two models consisting Always-busy and Always-idle ti simplify the general network congestion conditions. Through these models, moreover, we analyze two types MAC protocols in terms of energy efficiency and delay performance by analytical results. Additionally, we also evaluate two MAC protocols with two gongestion models that we designed. By the analytical and simulated results, we provide the general and efficient decision method in which protocols are more appropriate in a certain WSN environment.

Differences of Sensory Processing Abilities of Adults by Gender (성별에 따른 성인의 감각 처리 능력 차이)

  • Nam, Taek-Gil;Lee, Ji-Hyun
    • Journal of Korean Physical Therapy Science
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    • v.17 no.1_2
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    • pp.11-21
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    • 2010
  • Background: This study was undertaken to evaluate how gender differences affect the sensory processing by the Adolescent/Adult Sensory Profile(ASP) which evaluates the behavioral responses of adults to everyday sensory experiences. Methods: The study period lasted one month which was June 2009, and the study subjects were 325(three hundred twenty five) people who were healthy and reside in Chungcheong province including Daejeon. Detailed information about the study was explained to the study group and the ASP questionnaires were drawn up by them personally. Results: On average, the study group scores similarly in low registration, sensation seeking, sensory sensitivity, and sensation avoiding. According to the sensory processing abilities by gender, the group obtained scores indicating performance similar to most people in low registration, sensation seeking, and sensory sensitivity, except for sensation avoiding. Furthermore, in the taste/smell processing of "I only eat familiar foods", sensation avoiding score was higher in females than males, and in the activity level of "I find time to get away from my busy life and spend time by myself", males' sensation avoiding scored higher than females. Conclusion: In the study of differences of sensory processing abilities of adults by gender using the ASP, gender differences were revealed in the category of sensation avoiding.

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A Study of the Burden of Preceptors (프리셉터의 업무부담에 관한 연구)

  • Park Soo-Youn;Kim Ju-Sung;Kim Myung-Hee
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.10 no.1
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    • pp.37-46
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    • 2003
  • Purpose: This study investigated the burden of preceptors in order to improve preceptorship in nursing practice. Method: The participants were 170 preceptors at three hospitals in Pusan. The data were collected using questionnaires completed between July and September 2002, which included items to measure burden and opinions to reflect the demands of preceptors. They were analyzed using mean score, frequencies, and content analysis. Result: 1) The preceptors had an average of 6.3 years of clinical experience, while the practical career of a preceptor averaged 1.9 years. The average period of new nurse education was 5.5 weeks. Each year, 1.9 new nurses were trained per preceptor. 2) Of the preceptors 54.7% had received compensation without formal rules. but 54.1% did not want to serve further as preceptors because of overwork, lack of educational preparation, and lack of compensation. They were looking for solutions for existing problems. 3) Preceptors indicated that the major burden was having to repeat explanations to each preceptee, they were too busy to serve as preceptors, and their colleagues' had excessive expectations. Conclusion: We recommend practical management, including supplementary manpower, an education program, and compensation provided by the hospital administration with cooperation from colleges.

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Neither External nor Multilateral: States' Digital Diplomacy During Covid-19

  • Wu, Di;Sevin, Efe
    • Journal of Public Diplomacy
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    • v.2 no.1
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    • pp.69-96
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    • 2022
  • How does a public health crisis play into the digital rhetoric of states? As Covid-19 is presenting a situation in which countries need to manage the international environment in a relatively short period, their practices could signal how digitization is going to influence public diplomacy in the longer run. This paper explores state public diplomacy in the context of a public health crisis. It develops a theoretical framework of public diplomacy on social media through how and what states communicated during the first year of the Covid-19 pandemic. Through keyword and hashtag analyses, we identify two patterns. First, states usually regard social media as an instrument for domestic communication rather than public diplomacy. The international impact of messaging has not been prioritized or well-recognized. Social media platforms such as Twitter have global outreach and messaging can be seen by audiences all over the world. Messages intended for the domestic audience could have an international impact. Thus, any communication on digital platforms should consider their public diplomacy outcomes. Second, while social media platforms are claimed to be for networking at different levels, states tend to connect with other states rather than with international organizations during the pandemic. States do not like to mention international organizations like the WHO and the UN on Twitter. Instead, they were either busy dealing with internal problems or cooperating with another state to combat the virus.

A Study of Dorothy Wordsworth's Later Conversation Poetry (도로시 워즈워드의 후기 대화시 연구)

  • Cho, Heejeong
    • Journal of English Language & Literature
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    • v.57 no.2
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    • pp.191-215
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    • 2011
  • This paper aims at investigating Dorothy Wordsworth's later conversation poetry, which has not been the focus of critical discussions on her literary works. While many critics have been emphasizing Dorothy Wordsworth's journals and the tendency of self-effacement in her prose, this paper argues that her later poetry often reveals acute self-consciousness about the circumstances that condition this self-annihilation and searches for a creative way to endorse her own identity. In "Lines Intended for My Niece's Album," she expresses anxiety and uncertainty about the inclusion of her poetic piece in Dora Wordsworth's album, which contains poems by prominent male writers of the contemporary period. "Irregular Verses" presents Dorothy Wordsworth's self-conscious narrative of her girlhood and shows how her own ambition to become a "Poet" has been stifled by external circumstances, including the ideology that instills the idea of proper womanhood into aspiring girls. While these poems examine contemporary gender discourse and the frustrated poethood resulting from it, other poems activate conversations with William Wordsworth's poems and thereby provide a revisionary re-writing of her brother's texts. For example, in "Lines Addressed to Joanna H." Dorothy Wordsworth becomes "a woman addressed who herself addresses others." Her scrupulous approach to her own addressee refuses to subordinate the other to the self's will, and through this revision of "Tintern Abbey," Dorothy Wordsworth vicariously liberates her own self confined in her brother's poems. "Thoughts on My Sick-Bed," which echoes "Tintern Abbey" through borrowed phrases and direct address to William Wordsworth, foregrounds her own poetic identity in the form of the first-person pronoun "I." Dorothy Wordsworth's continual illness during this period of her life paradoxically allows her the time for personal reflection formerly denied to her in her busy life constantly occupied by physical and spiritual labor for others. Instead of earning satisfaction from the subsumption of her creative energy under William Wordsworth's poetical endeavor, Dorothy Wordsworth finally starts to affirm her own poetic identity that can properly express her inner vision and artistic talent. Although this final affirmation remains largely incomplete due to her later mental collapse bordering on madness, it powerfully conveys the hidden literary aspiration of the formerly frustrated female poet.