• Title, Summary, Keyword: set priority

Search Result 415, Processing Time 0.046 seconds

Delay analysis for a discretionary-priority packet-switching system

  • Hong, Sung-Jo;Takagi, Hideaki
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • /
    • pp.729-738
    • /
    • 1995
  • We consider a priority-based packet-switching system with three phases of the packet transmission time. Each packet belongs to one of several priority classes, and the packets of each class arrive at a switch in a Poison process. The switch transmits queued packets on a priority basis with three phases of preemption mechanism. Namely, the transmission time of each packet consists of a preemptive-repeat part for the header, a preemptive-resume part for the information field, and a nonpreemptive part for the trailer. By an exact analysis of the associated queueing model, we obtain the Laplace-Stieltjes transform of the distribution function for the delay, i.e., the time from arrival to transmission completion, of a packet for each class. We derive a set of equations that calculates the mean response time for each class recursively. Based on this result, we plot the numerical values of the mean response times for several parameter settings. The probability generating function and the mean for the number of packets of each class present in the system at an arbitrary time are also given.

  • PDF

Priority Determination in Nutrient Solution Management in Perlite Culture (펄라이트재배에서의 급액관리의 priority 설정)

  • 김영식
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.5 no.1
    • /
    • pp.7-12
    • /
    • 2004
  • The steps related to the nutrient solution management were divided into 4 categories. The resistance for water movement in every steps was proposed. The priorities among the steps were set according to the cultural situation, which were used as the basis for the management in perlite bag culture. The enhancement of historical root development is especially critical, as well as how to supply essential water efficiently by minimizing the water movement distance to the root, which is the narrowest neck of a bottle in solution management.

  • PDF

Determining Attribute Importance Weights Using Priority for Improvement Model

  • Song, HaeGeun;Kong, MyungDal
    • 대한설비관리학회지
    • /
    • v.23 no.4
    • /
    • pp.65-75
    • /
    • 2018
  • Importance-Performance Analysis(IPA) holds the assumption that the degree of physical fulfilment of quality attributes and the satisfaction of that attribute is linear. Therefore, IPA can be applied to the traditional one-dimensional attributes, not to other quality elements such as attractive or must-be attributes. To overcome this problem, several articles introduced methods that integrate IPA into the concept of two-dimensional quality. However, these articles are rather conceptual focusing on the differentiation of quality attributes depend on quality elements in IPA. To provide empirical evidence of the dependent relationship between attribute importance and satisfaction in IPA, this study introduces a weighted importance approach and provides validation method using Bacon's priority model, a regression model. For this, the current research investigates 23 quality attributes of TV set for the results of Kano's model, which are adopted from Kim et al., and conducted a survey of 118 university students for the results of the importance/satisfaction and improvement priority. The result of the proposed approach shows better result than those using the conventional way, based on R-square of the regression model.

Identifying Priority Area for Nonpoint Source Pollution Management and Setting up Load Reduction Goals using the Load Duration Curve (부하지속곡선을 이용한 비점오염원 우선관리 지역 선정 및 관리목표 설정 연구)

  • Jang, Sun Sook;Ji, Hyun Seo;Kim, Hak Kwan
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.60 no.5
    • /
    • pp.17-27
    • /
    • 2018
  • The objective of this study is to identify the priority area where the nonpoint source pollution (NPS) management is required and to set up the load reduction goals for the identified priority area. In this study, the load duration curve (LDC) was first developed using the flow and water quality data observed at 286 monitoring stations. Based on the developed LDC, the priority area for the NPS pollution management was determined using a three-step method. The 24 watersheds were finally identified as the priority areas for the NPS pollution management. The water quality parameters of concern in the priority areas were the total phosphorus or chemical oxygen demand. The load reduction goals, which were calculated as the percent reduction from current loading levels needed to meet target water quality, ranged from 67.9% to 97.2% during high flows and from 40.3% to 69.5% during moist conditions, respectively. The results from this study will help to identify critical watersheds for NPS program planning purposes. In addition, the process used in this study can be effectively applied to identify the pollutant of concern as well as the load reduction target.

An Improvement of the Schedulability Condition in Dynamic Priority Ceiling Protocol (동적 우선순위 상한 프로토콜의 스케줄링 가능성 조건 개선)

  • O, Seong-Heun;Yang, Seung-Min
    • Journal of KIISE:Computer Systems and Theory
    • /
    • v.28 no.11
    • /
    • pp.573-580
    • /
    • 2001
  • When tasks access shared resources in real-time systems, the unbounded priority inversion may occur. In such cases it is impossible to guarantee the schedulability of real-time tasks. Several resource access protocols have been proposed to bound the duration of priority inversion and sufficient conditions are given to guarantee the schedulability of periodic task set. In this paper, we show an improved sufficient condition for schedulability when the dynamic priority ceiling protocol is used. Our approach exploits the fact that a lower priority task can continue to execute as far as the higher priority tasks do not miss their deadlines. This permitting execution time of the higher priority tasks for a lower priority task can be excluded from the worst-case blocking time of the higher priority tasks. Since the worst-case blocking time of tasks can be reduced, the sufficient condition for schedulability of dynamic priority ceiling protocol becomes further tight.

  • PDF

A Design for Efficient Similar Subsequence Search with a Priority Queue and Suffix Tree in Image Sequence Databases (이미지 시퀀스 데이터베이스에서 우선순위 큐와 접미어 트리를 이용한 효율적인 유사 서브시퀀스 검색의 설계)

  • 김인범
    • Journal of the Korea Computer Industry Society
    • /
    • v.4 no.4
    • /
    • pp.613-624
    • /
    • 2003
  • This paper proposes a design for efficient and accurate retrieval of similar image subsequences using the multi-dimensional time warping distance as similarity evaluation tool in image sequence database after building of two indexing structures implemented with priority queue and suffix tree respectively. Receiving query image sequence, at first step, the proposed method searches the candidate set of similar image subsequences in priory queue index structure. If it can not get satisfied results, it retrieves another candidate set in suffix tree index structure at second step. The using of the low-bound distance function can remove the dissimilar subsequence without false dismissals during similarity evaluating process between query image sequence and stored sequences in two index structures.

  • PDF

A Comparitive Study of MAUT and AHP in Priority Setting of R&B Projects (연구개발사업 우선순위 설정에 있어서 다속성효용이론(MAUT)과 계층분석과정(AHP)의 비교)

  • 박주형;김정흠
    • Journal of Korea Technology Innovation Society
    • /
    • v.2 no.2
    • /
    • pp.201-218
    • /
    • 1999
  • The article contains an introduction of possibility of applying Multi-Attribute Utility Theory(MAUT) for priority setting of R&D projects. MAUT is compared with AHP, which is widely used recently. These two techuiques are applied to set priorities of R&D projects In a Government-funded Research Institute. Six criteria are chosen from consultation with decision makers. They are composed of 1) validity as representative projects, 2) possibility of resource mobilization, 3) spillover effect of developed technologies, 4) possibility of success, 5) scope of participation and 6) clarity of research goal. To set priorities of R&D projects, SMART(Simple MultiAttribute Rating Technique) and DVM(Difference Value Measurement) out of many MAUT methods are used to design the utility function and to determine the weights among criteria. The aggregation model is additive on the assumption the criteria are independent. AHP executes pairwise comparisons for criteria and alternatives. From the results of the case study, the results and theoretical characteristics are compared.

  • PDF

Priority Areas for National Health Care Quality Evaluation in Korea (의료의 질 평가 우선순위 설정)

  • Shin, Suk-Youn;Park, Choon-Seon;Kim, Sun-Min;Kim, Nam-Soon;Lee, Sang-Il
    • Health Policy and Management
    • /
    • v.19 no.3
    • /
    • pp.1-26
    • /
    • 2009
  • Objectives : To identify target areas and set priorities among those areas identified for national quality evaluation. Methods : Target areas were identified from: i) analysis of the national health insurance claims data, mortality and prevalence data ii) various group surveys, including representatives from 22 medical specialty associations, 19 physician associations, QI staffs in hospital, civil organizations, and commissioners of Health Insurance Review and Assessment Service(HIRA) ⅲ) literature reviews and RAM(RAND/UCLA appropriateness method). The priority areas for national quality evaluation represented the full spectrum of health care and the entire life span. The criteria for selecting the priority areas were impact, improvability, and measurability. The priority areas were divided into three categories : short-term, mid-term, long-term. Results: Based on the group surveys and the data analysis, 46 candidates were selected as quality evaluation priority areas. 13 areas were selected as having a short-term priority areas: tuberculosis, community acquired pneumonia, stroke, ischaemic heart disease, diabetes, hypertension, chronic lower respiratory disease(asthma, chronic obstructive pulmonary disease), intensive care unit, emergency room, nosocomial infection, use of antibiotics, multiple medication and renal failure. This results suggested that we need to enlarge the target priority areas to the chronic diseases in short-term. Conclusions: The priority areas identified from the study will assist healthcare quality associated institutions as well as HIRA in selecting quality evaluation areas. It is required to develope and implement strategies for improving the quality of care within the next 5 years.

A start-up class model in multiple-class queues with N-policy and general set-up time (N-정책과 준비기간을 갖는 시동계층모형의 분석)

  • Yoon, Seung-Hyun;Lee, Ho-Woo;Seo, Won-Ju
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.25 no.1
    • /
    • pp.141-149
    • /
    • 1999
  • In this paper, we consider multiple-class queueing systems in which the server starts a set-up as soon as the number of customers in the "start-up class" reaches threshold N. After the set-up the server starts his service. We obtain the Laplace-Stieltjes transform and the mean of the waiting times of each class of customers for FCFS and non-preemptive priority disciplines.

  • PDF

A Performance Improvement Study On Hierarchical Clustering (Centroid Linkage) Using A Priority Queue (Priority Queue 를 이용한 Hierarchical Clustering (Centroid Linkage) 성능 개선)

  • Jeon, Yongkweon;Yoon, Sungroh
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • /
    • pp.1837-1838
    • /
    • 2010
  • 기존 hierarchical clustering 은 Time complexity 와 space complexity 가 Large data set 을 clustering 하기에는 적당하지 못하며 이것을 일반 PC 의 메모리 내에서 해결하는데 어려움이 있다. 따라서 본 연구에서는 이러한 어려움을 극복하기 위해 기존 Hierarchical clustering 중 Centroid Linkage 에 새로운 Algorithm 을 제안하여 보다 적은 메모리를 사용하고 빠르게 처리하는 방법을 제안하고자 한다.

  • PDF