• Title/Summary/Keyword: LOB

Search Result 44, Processing Time 0.036 seconds

Extending SQL CLI for Large Object Caching (LOB 캐쉬를 위한 SQL CLI의 확장)

  • 이종민;강현철
    • The KIPS Transactions:PartD
    • /
    • v.8D no.1
    • /
    • pp.1-9
    • /
    • 2001
  • The SQL CLl (Call Level Interface) is a database application programming interface (API) that fits the client-server environment, and its de facto standards such as ODBC and JDBC are widely employed in various applications. The current SQL CLl standards, however, do not specify enough features for efficient retrieval of large objects (LOBs) that constitute the multimedia data. In this paper, we propose the LOB caching through the SQL CLl and describe the extension of the SQL eLl to achieve such a goal. We implement our proposal by extending the SQL CLl library for BADA - II DBMS developed at ETRI, and evaluate the performance of LOB retrieval through the cache compared to that of LOB retrieval conducted solely with the functions specified in the current SQL CLl standards.

  • PDF

Performance of LOB-based Emitter Localization Using Linear LSE Algorithms (선형 LSE 알고리즘을 이용한 신호원 위치 추정 성능)

  • Lee, Joon-Ho;Kim, Min-Cheol;Cho, Seong-Woo;Kim, Sang-Won
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.13 no.1
    • /
    • pp.36-40
    • /
    • 2010
  • In this paper, the well-known LOB-based emitter localization using linear LSE algorithm is numerically implemented and the heuristic guidelines for the parameter values to achieve 1% RMS error are presented. In the simulation, we changed the total observation durations for LOB measurements, time interval between successive LOB measurements and sensor trajectories. The effects of the time interval of LOB measurements, the time duration of the LOB measurements and the angle of flight path arc on the performance are illustrated. The dependence of the performance on the various parameters is investigated and rule-of-thumbs for the parameter values corresponding to 1% RMS error are presented for each simulation condition.

Vector Analysis of LOB (LOB의 벡터 해석)

  • 이재관
    • Journal of the Korean Operations Research and Management Science Society
    • /
    • v.4 no.2
    • /
    • pp.45-50
    • /
    • 1979
  • This paper tries to show that LOB, a graphic device, can be equipped with the vector concept. The notations, calculations, and relationships of useful vectors are introduced and the general procedure for Vector Analysis of LOB is applied in this paper. Comparing vector analysis with graphical method, the author concludes that the former is more powerful than the latter in production control.

  • PDF

Crashing Method for Repetitive Project hybridizing concurrent engineering and LOB (동시공학 및 LOB를 사용한 반복 프로젝트 공기단축 방법론)

  • Min, Gyu-Tae;Lee, Hong-Chu;Li, Xian-Jun;Lee, Dong-Eun
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2018.05a
    • /
    • pp.41-42
    • /
    • 2018
  • Various methods that crash the project completion time have been studied. Line-of-Balance (LOB) is well accepted as a useful method that enables steady resource utilization without frequent hire-and-fire of resources for a project having repetitive units. Existing studies involved in LOB-CPM focuses on thesis such as resource leveling and optimization in construction scheduling community. However, crashing methods are not arrived at a full maturity in LOB scheduling, because no one handles steady resource utilization while keeping activity-relationships. This paper proposes a method that crashes project completion time by hybridizing concurrent engineering and LOB scheduling without using additional resources.

  • PDF

Extending SQL CLI To Support LOB Caching in a Personal Computing Environment (개인 컴퓨팅 환경에서 LOB 캐쉬를 지원하기 위한 SQL CLI의 확장)

  • 이종민;강현철
    • Proceedings of the Korean Information Science Society Conference
    • /
    • 1999.10a
    • /
    • pp.234-236
    • /
    • 1999
  • 망 환경에서 PC 사용자들의 멀티미디어 데이타 검색이 점차 증가하고 있다. SQL CLI(Call Level Interface)는 클라이언트-서버 환경에 적합한 데이터베이스 응용 프로그래밍 인터페이스(API)로서, 현재의 표준안에서는 멀티미디어 데이터와 같은 대용량 데이터의 효율적 검색을 위한 기능을 다양하게 제공해 주지 못하고 있다. 본 논문에서는 멀티미디어 데이터를 구성하는 LOB(Large OBject)의 빠른 검색을 위하여 SQL CLI 상에서 LOㅠ의 캐쉬를 제안하고, 이를 위한 SQL CLI 함수의 확장을 제안한다. 그리고 제안한 함수 중 일부를 SQL CLI를 지원하는 실제 DBMS 상에서 구현하여 LOB 캐쉬의 성능을 평가한다.

  • PDF

Stochastic Scheduling for Repetitive Construction Projects

  • Lee, Hong-Chul;Lee, Dong-Eun
    • International conference on construction engineering and project management
    • /
    • 2015.10a
    • /
    • pp.166-168
    • /
    • 2015
  • Line of Balance (LOB) method is suitable to schedule construction projects composed of repetitive activities. Since existing LOB based repetitive project scheduling methods are deterministic, they do not lend themselves to handle uncertainties involved in repetitive construction process. Indeed, existing LOB scheduling dose not handle variability of project performance indicators. In order to bridge the gap between reality and estimation, this study provides a stochastic LOB based scheduling method that allows schedulers for effectively dealing with the uncertainties of a construction project performance. The proposed method retrieves an appropriate probability distribution function (PDF) concerning project completion times, and determines favorable start times of activities. A case study is demonstrated to verify and validate the capability of the proposed method in a repetitive construction project planning.

  • PDF

Efficient Incorporation of Tertiary Storage in a Multimedia DBMS (멀티미디어 DBMS에서 3차 저장장치의 효율적 활용 기법)

  • Mun, Chan-Ho;Gang, Hyeon-Cheol
    • The Transactions of the Korea Information Processing Society
    • /
    • v.6 no.7
    • /
    • pp.1724-1737
    • /
    • 1999
  • Multimedia data service applications have to store and manipulate LOBs(unstructured large objects) composing multimedia data. As such, the tertiary storage devices such as an optical disk jukebox and a tape library that consist of a number of platters (the disks in case of an optical disk jukebox and the cartridge tapes in case of a tape library) have been considered essential for the storage system of a DBMS in order to efficiently support storage and management of vary large volume of data. Since the latency with tertiary storage is too long, the schemes for efficient retrieval of LOBs out of tertiary storage need to be investigated. In this paper, we investigated the tertiary I/O Considering the performance characteristics of the LOBs, we proposed various I/O scheduling heuristic algorithms that reduce latency in query processing with LOB retrieval from tertiary storage, and evaluated their performance through a detailed simulation.

  • PDF

Performance Analysis of Emitter Localization Using Kalman Filter (Kalman filter를 이용한 위치추정 알고리즘의 성능 분석)

  • Lee, Joon-Ho;Cho, Seong-Woo;Lee, Dong-Keun
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.12 no.6
    • /
    • pp.727-732
    • /
    • 2009
  • In this paper, the dependence of the Kalman filter-based emitter location algorithm on the initial estimate is investigated. Given all the LOB data, the initial estimate of the emitter location is obtained from the linear LSE algorithm with the former LOB data. Using the initial estimate, the Kalman filter algorithm is applied with the remaining LOB data to update the initial estimate. It is shown that as the number of data used in the calculation of the initial estimate increases, the accuracy of the final estimate is improved and the total computational complexity of obtaining the initial estimate and the final estimate increases. In addition, the dependence of the performance of the Kalman filter algorithm on the predefined constant is illustrated.

Dependence of LOB-based Emitter Localization Performance on Bias of Emitter Location and Sensor Trajectory (신호원 위치의 편향성 및 센서 이동경로에 따른 선형 LSE 알고리즘 기반 신호원 위치 추정 성능)

  • Lee, Joon-Ho;Cho, Seong-Woo;Kim, Min-Cheol;Jin, Yong-Ki;Lee, Chang-Hoon
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.12 no.5
    • /
    • pp.585-589
    • /
    • 2009
  • In this paper, passive direction-finding localization of the emitter using noisy line-of-bearing (LOB) measurements is considered. The performance of the LOB-based emitter localization using linear LSE algorithm is given. The Dependence of the performance on bias of emitter location and sensor trajectory is illustrated using the numerical results.

Sensitivity Analysis and Optimization of Design Variables Related to an Algorithm for Loss of Balance Detection (균형상살 검출 알고리즘에서 검출과 관련된 설계변수의 민감도 해석 몇 최적화)

  • Ko, B.K.;Kim, K.H.;Son, K.
    • Journal of Biomedical Engineering Research
    • /
    • v.32 no.1
    • /
    • pp.7-14
    • /
    • 2011
  • This study suggested an optimized algorithm for detecting the loss of balance(LOB) in the seated position. And the sensitivity analysis was performed in order to identify the role of each design variable in the algorithm. The LOB algorithm consisted of data processing of measured signals, an internal model of the central nervous system and a control error anomaly(CEA) detector. This study optimized design variables of a CEA detector to obtain improved values of the success rate(SR) of detecting the LOB and the margin time(MT) provided for preventing the falling. Nine healthy adult volunteers were involved in the experiments. All the subjects were asked to balance their body in a predescribed seated posture with the rear legs of a four-legged wooden chair. The ground reaction force from the right leg was measured from the force plate while the accelerations of the chair and the head were measured from a couple of piezoelectric accelerometers. The measured data were processed to predict the LOB using a detection algorithm. Variables S2, h2 and hd are related to the detector: S2 represents a data selecting window, h2 a time shift and hd an operating period of the LOB detection algorithm. S2 was varied from 0.1 to 10 sec with an increment of 0.1 sec, and both h2 and hd were varied from 0.01 to 1.0 sec with an increment of 0.01 sec. It was found that the SR and MT were increased by up to 9.7% and 0.497 sec comparing with the previously published case when the values of S2, h2 and hd were set to 4.5, 0.3 and 0.2 sec, respectively. Also the results of sensitivity analysis showed that S2 and h2 had considerable influence on the SR while these variables were not so sensitive to the MT.