• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.257-260
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• 2001

Buffers, on which much research is being done, are being used as a means to alleviate impacts in processes. Impacts occur from variation which is caused by uncertainty. Current buffers just accept variation as it comes and have just been used as a means to reduce impact. The purpose of this research try to understand the assorted variations which arise from limited resources and information and then we present a division of buffers as the way to overcome these variations. Through the process of dividing buffers into screening buffers, pulling buffers, shielding buffers, and working buffers, we try to make the process more compact, eliminate unnecessary reduction, speed up the decision making process by excluding excessive information, and improve the reliability of work.

• Journal of information and communication convergence engineering
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• v.8 no.6
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• pp.721-724
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• 2010

In a network router, packet loss may occur when it overflows due to sudden burst traffic. This paper studies how much large buffers are required to eliminate the packet losses. There are buffers on which packet arrive and one output port to which a packet is transmitted at a time. The buffer management algorithm should determine one of the buffers whose packet is transmitted to the output port at each time. The front packet belonging to the buffer determined by the algorithm is transmitted. The goal is to minimize the sum of the lengths of buffers to transmit all the packets. We provide an optimal off-line algorithm and also we show the lower bounds of on-line algorithms. The on-line algorithm has no prior information of the packets having arrived in the future. Its performance is compared to that of the optimal off-line algorithm.

• Korean Journal of Remote Sensing
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• v.22 no.5
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• pp.445-449
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• 2006

Diffuse pollution has been considering as a major source of the quality deterioration of water resources. The establishment of riparian vegetation strips or buffers along those areas of water bodies is used to reduce the threat of diffuse pollution. Remote sensing offers a means by which critical areas could be identified, so that subsequent action toward the establishment of riparian zones can be taken. On the behalf of KOMPSAT-2 satellite imagery as a high resolution spatial data, Landsat TM satellite data are used to aquire the land cover for the riparian buffers studied. This investigation aims to assess the riparian buffers established on the upper Geum river as a pollution mitigation. Through comparing the delineation of riparian buffer zones developed with the existing zones established by the government, we can find the critical distortion points of the existing riparian buffer zone.

• The Korean Journal of Pharmacology
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• v.8 no.2
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• pp.63-69
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• 1972

The effects of omission of buffers from Krebs-Ringer medium on contractile activity, membrane potentials and ATP content of electrically stimulated isolated rat atria were investigated. 1) Contractile status: A rapid and marked depression of the contractile activity of atria occurred when buffer-free medium was substituted for the normal Krebs-Ringer medium. 2) Electrical status: The omission of buffers from medium did not alter the resting or action potential magnitudes of atria. However, the action potential duration was on initial increase followed by a decrease in the buffer-free medium. 3) ATP concentration: The omission of buffers from medium resulted in a marked decrease in the ATP levels of atria. It has been also found in the present study that bicarbonate buffer plays an important role for the maintenance of the contractility and ATP levels of the heart. The contractile depression by the omission of buffers was not directly associated with electrical alterations in resting or action potentials of the heart. In the absence of bicarbonate-buffer, glucose no longer plays to maintain the contractile activity and the ATP levels of rat atria.

• Journal of applied mathematics & informatics
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• v.26 no.1_2
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• pp.299-306
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• 2008

Finite difference schemes are considered for a $Ca^{2+}$ diffusion equations, which discribe $Ca^{2+}$ buffering by using stationary and mobile buffers. Stability and $L^\infty$ error estimates of approximate solutions for the corresponding schemes are obtained using the extended Lax-Richtmyer equivalence theorem.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.15 no.26
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• pp.151-157
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• 1992

This paper presents a method for analyzing the transfer lines with finite storage buffers. Each machine spends a random amount of time processing each material. This transfer line can be modeled by the tandem queueing system with finite buffers. The great dimensionality of the state space renders the analysis of such system a formidable task. We propose an efficient algorithm to obtain the marginal state probabilities based on the exact algorithm for the two-machine system. Other performance measures, such as the utilization, the blocking probability, the average sojourn time, and the average queue length, can be easily calculated.

• Journal of the Korean Operations Research and Management Science Society
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• v.30 no.2
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• pp.73-80
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• 2005

In this paper, we consider characteristics of waiting times in s1n91e-server 3-node tandem queues with finite buffers, a Poisson arrival process and deterministic service times at all nodes. There are three buffers : one at the first node is infinite and the others are finite. We obtain the fact that sojourn time or departure process is independent of the capacities of the finite buffers and does not depend on the order of service times, which are the same results in the literature. Moreover, the explicit expressions of stationary waiting times in all areas of the systems can be derived as functions of the finite buffer capacities. We also disclose a relationship of waiting times in subareas of the systems between two blocking policies communication and manufacturing. Some numerical examples are also provided.

• Journal of applied mathematics & informatics
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• v.22 no.1_2
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• pp.523-533
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• 2006

We analyze two finite buffers queueing system with priority scheduling dependent upon queue length. Customers are classified into two types ( type-l and type-2 ) according to their characteristics. Here, the customers can be considered as traffics such as voice and data in telecommunication networks. In order to support customers with characteristics of burstiness and time-correlation between interarrival, the arrival of the type-2 customer is assumed to be an Markov- modulated Poisson process(MMPP). The service order of customers in each buffer is determined by the queue length of two buffers. Methods of embedded Markov chain and supplementary variable give us information for queue length of two buffers. Finally, performance measures such as loss and mean delay are derived.

• Journal of the Korea Computer Graphics Society
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• v.2 no.2
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• pp.1-9
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• 1996

It is important issue to increase the efficiency of visibility operations in rendering since the most of rendering time is spent for performing visibility operations. In this paper, we present light buffers of area light sources, which provide efficient visibility operations from the sources. The light buffers are extended to support visibility operations not originated from the sources. We also explore their applications such as shadow generation, ray tracing and radiosity. Our experimental results show that the light buffers support more efficient visibility operations than the previously developed data structures including BSP trees, linear grids, and octrees.

• Journal of the Korean Operations Research and Management Science Society
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• v.22 no.1
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• pp.123-140
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• 1997

In this paper we consider closed flow line systems with samploing inspections. The total number of parts in the system is assumed to be N. The processings carried out of each station do not always meet the requirement of quality. Therefore, upon completion of its processing at each station, a part is inspected to determine whether the processings meet the requirement of quality or not. We assume that inspection are done on a random basis. If a part is found to be defective by an inspection, it is fed back to the apropriate station. Two different cases will be considered in this study : a three-station flow line system with infinite buffers and a two-station flow line system with finite buffers. For each case, we will develop an exact method to obtain the performance measures such as throughput, machinen utilization, average outgoing quality and manufacturing lead time. For the case of the two-station flow line system ith finite buffers, we will also develop an approximation method using a stage-aggregation technique. Then using buffers, we will also develop an approximation method using a stage-aggregation technique. Then using these results, we will try to find an optimal inspection policy which maximizes the expected net profit under a certain cost structure. Although we present the results only for the two or three station flow line system in this paper, the results obtained in this paper can be extended easily to the system which consists of more than two or three stations.