• 산업공학
• /
• 제10권1호
• /
• pp.37-45
• /
• 1997

본 연구에서는 웨이퍼 팹공정에서 웨이퍼 로트들이 뱃치공정을 위해 확률적으로 도착되는 상황에서 최적 뱃치크기를 결정하는 뱃칭문제를 다루고 있다. 뱃치공정이란 여러 개의 웨이퍼 로트들을 기계의 용량을 넘지 않는 한도 내에서 하나의 뱃치로 구성하여 한꺼번에 가공하는 공정을 말한다. 목적함수는 생산율을 높이고 재공재고 및 사이클타임을 줄이기 위해 웨이퍼 로트들의 평균 대기시간의 최소화를 채택하였다. 문제의 해결을 위해서, 확률적인 상황변동 하에서 실시간 제어를 위해 많이 활용되고 있는 신경회로망 중 다층 퍼셉트론을 이용한 뱃치크기 결정 모델을 제시하였다. 제시한 모델의 효율성을 확인하기 위해 기존에 잘 알려져 있는 최저뱃치크기(MBS) 규칙과 실험, 비교하였다.

• 한국경영과학회지
• /
• 제28권4호
• /
• pp.105-114
• /
• 2003

This paper considers a single facility scheduling problem for the fabrication of components supporting the subsequent assembly into products. Each product consists of two types of components, one is common to all products and the other is unique to itself. The unique components are processed individually and the common components are processed in batches, and a distinct setup is incurred for the production of a batch of common components. Under the so-called “batch availability” environment, we propose an efficient dynamic programming(DP) procedure for the optimal sequencing and batching schedule with minimum total completion times of products in the situation that each product is said to be complete if both common and unique components of the product are finished. Computational results show that the proposed DB procedure is more efficient than the previous work which has considered the same problem as this paper.

• 한국정보처리학회논문지
• /
• 제7권2S호
• /
• pp.656-665
• /
• 2000

A critical issue in the performance of a video-on-demand system is the I/O bandwidth required in order to satisfy client requests. Several approaches: batching, bridging, piggybacking are used ot reduce the I/O demand on the video server through sharing. Piggybacking is the policy for altering display rates of requests in progress fro the same object, for the purpose of merging their corresponding I/O streams into a single stream, which can serve the entire group of merged requests. In this paper, we propose a new policy called an adaptive reservation-based piggybacking that dynamically reserves the I/O stream capacity of video server for popular videos according to video server loads to immediately schedule the requests for popular videos. The performance of the proposed policy is evaluated through simulations, and is compared with that of simple piggybacking. As the result, we know that the adaptive reservation-based piggybacking provides better service probability, average waiting time and percentages saving in frames than simple piggybacking.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제13권12호
• /
• pp.6260-6276
• /
• 2019

With the rapid development of cloud computing, it raises real questions on privacy protection, which greatly limits the use of cloud computing. However, fully homomorphic encryption (FHE) can make cloud computing consistent with privacy. In this paper, we propose a simpler FHE scheme based on ring LWE problem, with a smaller size of ciphertext and a lower noise-expansion factor for homomorphic multiplication. Then based on our optimized RLWE-based FHE scheme, we propose a fast single-database private information retrieval protocol, combining with batching and number theoretic transform technology.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
• /
• pp.492-496
• /
• 1988

As computer systems get complex more and more, the powerful but easy-to-use man machine interfaces are required. This paper describes the man machine interface in the TDX-10 switching system currently being developed at ETRI. The man machine interface in TDX-10 provides a reliable and user-friendly system interface through which system operators can manage the system in a convenient way. It incorporates the window, menu, form, on-line help, history recording, command file batching and color graphics capabilities.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2000년도 ITC-CSCC -1
• /
• pp.322-325
• /
• 2000

In a batch scheduling policy being different from real video system, the requests are not served immediately due to grouping user's requests upon every scheduling points. Such waiting delays by inefficient managements makes an unfair service to users and increases the possibility of higher reneging rates. This paper proposes an adaptive batch scheduling scheme which reduces the average waiting time of user’s requests and reduces the starvation problem for requesters of less popular movies. The proposed scheme selects dynamically multiple videos in given intervals based on the service patterns which reflect the popularity distribution and resource utilizations. Experimental simulation shows that proposed scheme improves about 20-30 percent of average waiting time and reduces significantly the starving requesters comparing with those of conventional methods such as FCFS and MQL.

• 산업공학
• /
• 제16권1호
• /
• pp.44-53
• /
• 2003

Ready-Mixed Concrete transportation business has been managed by the manual operation and intuitive decision making. This study is on the process improvement on ordering process, and allocation/transportation of trucks commuting between the batching plant and construction sites. Processes of order collection, job dispatch and allocation, and on-time-delivery are analysed and improved. The logistics control system, with GPS system, was developed and implemented based on the reconstructed processes. Performances are evaluated after improved business process and logistics system was applied, and it is shown that waiting time loss is decreased by 55%, and that efficiency is increased by 15%.

• 대한산업공학회지
• /
• 제40권2호
• /
• pp.215-222
• /
• 2014

This paper provides a real-time loading strategy for batch processing machines in which a number of jobs are simultaneously processed as a batch. The batch processing machines can be seen in both manufacturing industries (e.g., semiconductor, automobile and metal working) and service industries (transportation vehicles, mail shipment and theme park). This paper focuses on batch processing machines in semiconductor manufacturing. We present a look-ahead loading strategy for tardiness minimization where future arrivals and due dates are taken into consideration. Simulation tests are performed on the presented strategy and some existing loading heuristics under various production settings with different traffic intensities and forecasting errors. Experimental results show that our strategy provides the performance of good quality.

• 한국컴퓨터정보학회논문지
• /
• 제23권11호
• /
• pp.59-66
• /
• 2018

Data Distribution Service(DDS) provides the communications service programmers need to distribute time-critical data between embedded and/or enterprise devices or nodes. In this paper, I propose efficient methods for transmitting and receiving messages of various characteristics in real-time using DDS middleware. For high-frequency characteristic data, I describe several DDS packet types and various default and extended DDS QoS policies. In particular, the batching method is probably the best solution when considering several performance aspects. For large-capacity characteristic data. I will show a method using extended DDS QoS policies, a segmentation and reassembly method, and transmitting and receiving a large-capacity data with low priority method considering network conditions. Finally, I simulate and compare the result of performance for each methods. This results will help determine efficient methods for transmitting and receiving messages of various characteristics using DDS middleware.

• 정보처리학회논문지B
• /
• 제9B권6호
• /
• pp.835-844
• /
• 2002

비디오 서버가 제공할 수 있는 채널의 개수는 서버의 통신 대역폭에 의해 결정되므로 비디오 서버의 가용 채널 수는 제한되어 있다. 멀티캐스트 데이터를 공유함으로써 비디오 서버에 대한 I/O 요구를 절감시키기 위하여 일괄처리, 피기백킹 그리고 패칭과 같은 여러 방법들이 제안되었다. 특히 패칭은 VOD 시스템을 위한 비용에 있어서 효율적인 것으로 보여지고 있다. 패칭은 일반적인 멀티캐스트 기법과 달리 새로운 요청을 진행중인 멀디캐스트에 합병할 수 있게 하는 동적 멀티캐스트 방법이다. 더욱이, 새로운 요청은 다음 멀티캐스트를 기다리지 않고 즉시 서비스될 수 있으므로 true VOD를 이룰 수 있다. 본 논문에서, 우리는 고정 채널 예약 패칭과 가변 채널 예약 피칭이라는 두 가지 채널 예약 패칭 알고리즘을 제안한다. 인기 비디오에 대한 용청들을 즉시 스케줄하기 위하여, 제안하는 알고리즘들은 고정된 개수의 인기 비디오 또는 서버의 부하에 따라 동적으로 결정되는 가변 개수의 인기 비디오를 위하여 비디오 서버의 채널들을 예약한다. 제안하는 알고리즘들의 성능은 시뮬레이션을 통하여 평가되었고, 단순 패칭의 성능과 비교하였다. 사용된 성능 척도는 비디오 서버 부하에 다른 평균 이탈율, 평균 대기 시간, 서비스 공평성 그리고 버퍼량이다. 시뮬레이션 결과는 우리가 제안하는 채널 예약 패칭 알고리즘들이 단순 패칭보다 성능이 더 나음을 보였다.