• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.40 no.11
• /
• pp.73-82
• /
• 2003

In this paper, a simultaneous buffer insertion and routing method is proposed under the constraints of wire and buffer locations by macro or IP blocks. A new grid graph is proposed to describe the regions in which buffers(or both wires and buffers) are not available. Under this grid we describe a method of constructing a buffeted tree that minimize the maximum source to sink delay. The method is based on the dynamic programming with pruning unnecessary partial solutions. The proposed method improved the slack time of the delay by 19% on the average while using less buffers and similar wire length.

• Korean Management Science Review
• /
• v.28 no.3
• /
• pp.15-29
• /
• 2011

In this paper, we consider a system working at both primary service and secondary service. A server can switch between the primary service and the secondary service or it can be assigned to secondary service as a dedicated server. A service policy is characterized by the number of servers dedicated to the secondary service and a rule for switching the remaining servers between two services. The primary service system is modelled as a Markovian queueing system and the throughput is a function of the number of servers, buffer capacity, and service policy. And the secondary service system has a service level requirement strategically determined to perform the service assigned. There is a revenue obtained from throughput and costs due to servers and buffers. We study the problem of simultaneously determining the optimal total number of servers, buffers, and service policy to maximize profit of the system subject to both an expected customer waiting time constraint of the primary service and a service level constraint of the secondary service and develop an algorithm which can be successfully applied with the small number of computations.

• Journal of the Semiconductor & Display Technology
• /
• v.22 no.4
• /
• pp.59-65
• /
• 2023

Edge detection in image processing and computer vision is one of the most fundamental operations. Canny edge detection algorithm has excellent performance and is currently widely used. However, it is difficult to process the algorithm in real-time because the algorithm is complex. In this study, the equations required in the algorithm were simplified to facilitate hardware implementation, and the calculation speed was increased by using a parallel structure. In particular, the size and management of local buffers were selected in consideration of parallel processing and filter size so that data could be processed without bottlenecks. It was designed in verilog and implemented in FPGA to verify operation and performance.

• Korean Journal of Veterinary Research
• /
• v.30 no.1
• /
• pp.41-49
• /
• 1990

These experiments were carried out to develop a novel, simple, and rapid method to determine urinary sulfonamides using fluorescamine by spectrofluorometry. To get optimal conditions for the sulfonamide-fluorescamine reaction, sulfonamides such as sulfamethazine, sulfamerazine, sulfadimethoxine and sulfamonomethoxine, dissolved in buffers with various pH ranges were reacted with various concentrations of fluorescamine. and then, the fluorescence intensity and stability of the fluorophore were measured. To eliminate the interfering substances in urine, the fluorophore in buffers and urine with a definite pH range was extracted with some organic solvents. After then the fluorescence intensity was measured in organic and aquous phases. The results obtained were summarized as follows: 1. The maximal fluorescence of sulfonamides was presented in acidic state, pH 4.5~5.0, at 30 minutes after reaction. 2. The optimal concentration ratio of sulfamethazine and ffuorescamine was more than 1 : 40 in mole. 3. In pH 4.0, the intensity was maximal but was time-dependent, whereas in pH 8.0, the intensity was time-independent. 4. Sulfamethazine-fluorescamine conjugate could be dissolved in some of organic solvents in acidic state such as chloroform, n-butanol, and ethylacetate. 5. Sulfamethazine-flnorescamine conjugate in swine urine coule be extracted with ethylacetate in acidic state, pH 4.0~5.0.

• Journal of Korea Society of Industrial Information Systems
• /
• v.9 no.2
• /
• pp.23-31
• /
• 2004

This paper focuses on a boundary surface based ray casting. In general the boundary surface based ray casting is processed in two stages. The first stage finds boundary surfaces and stores them into buffers. The second stage calculates a distance from a viewpoint to the voxels of the interested area by projecting boundary surfaces on the view plane, and then starts to traverse a volume data space with the distance. Our approach differs from the general boundary surface based ray casting in processing the first stage of it. Contrast to the typical boundary surface based ray casting where all boundary surfaces of volume data are stored into buffers, they are projected on the planes aligned to the axis of volume data coordinates and these projected data are stored into 6 buffers. Such maneuver shortens time for ray casting, and reduces memory usage because it can be carried out independently from the amount of the volume data.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.33A no.6
• /
• pp.23-32
• /
• 1996

This paper proposes a new buffer management scheme to service delay-sensitive traffic and loss-sensitive traffic fairly in ATM networks. The proposed scheme uses tow buffers for delay-sensitive traffic and loss-sensitive traffic. To satisfy the average delay time of delay-sensitive traffic, cells in real-time buffer are served first. When congestion occurs in nonreal-time buffer, low loss priority cell in real-time buffer can be pushed out by high loss priority cell in nonreal-time buffer can be transferred to real-time buffer considering threshold value in real-time buffer. Using computer simulation, the existing methods and proposed scheme are compared and analyzed with respect to cell loss rate and average delay time. Simulation results show that the proposed scheme have superior performance to conventional schemes.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.67 no.2
• /
• pp.270-276
• /
• 2018

Apache Spark is one of the high performance in-memory computing frameworks for big-data processing. Recently, to improve the performance, general-purpose computing on graphics processing unit(GPGPU) is adapted to Apache Spark framework. Previous Spark-GPGPU frameworks focus on overcoming the difficulty of an implementation resulting from the difference between the computation environment of GPGPU and Spark framework. In this paper, we propose a Spark framework based on a heterogenous pipeline computing with OpenCL to further improve the performance. The proposed framework overlaps the Java-to-Native memory copies of CPU with CPU-GPU communications(DMA) and GPU kernel computations to hide the CPU idle time. Also, CPU-GPU communication buffers are implemented with switching dual buffers, which reduce the mapped memory region resulting in decreasing memory mapping overhead. Experimental results showed that the proposed Spark framework based on a heterogenous pipeline computing with OpenCL had up to 2.13 times faster than the previous Spark framework using OpenCL.

• The Transactions of the Korea Information Processing Society
• /
• v.4 no.12
• /
• pp.3175-3184
• /
• 1997

To support large storage capacity and real-time characteristics of continuous media storage systems, we need to improve the performance of disk I/O subsystems. To improve the performance, we exploited buffer sharing scheme that reduces the number of disk I/Os. We utilized the advance knowledge of continuous media streams that is used to anticipate data demands, and so Promoting the sharing of blocks in buffers. In this paper, we proposed a buffer replacement algorithm that enables subsequent users requesting the same data to share buffer efficiently. The proposed algorithm manages buffers by utilizing reference interval information of blocks. In order to verify validity of the proposed algorithm, we accomplished simulation experiments and showed the results of performance improvements compared to traditional buffer replacement algorithms.

• Korean Journal of Social Welfare
• /
• v.46
• /
• pp.319-348
• /
• 2001

The primary purpose of this study is to examine the buffering effect of social welfare services on the relationship between the level of older persons' impairment and burden experienced by the family caregivers. It also assessed the level of caregiving burden as well as the effect of both older person's impairment and the characteristics of the caregivers on burden. The survey data collected from 150 community residing family caregivers was used for analyses. Findings are as follows. First, the caregivers are more burdened in the deterioration of mental health, scarce time for oneself, and the suffering of social life than in other areas of burden. Second, the more severe the physical and the mental impairment of the elder, the more burden the caregivers experience. The caregivers' characteristics such as the worse mental health, the lower level of attachment to the elder, the longer caregiving hours are also related to the higher level of caregiving burden. Third, the caregivers' use of adult day care and respite care services buffer the relationship between the level of impairment of older persons and the caregiving burden. However, social work counselling, visiting nurse, homemaker services do not have such buffering effects. Among informal support, instrumental support buffers the relationship between the elder's physical impairment and burden, while emotional support buffers the relationship between the elder's mental impairment and burden. According to the results, implication for social welfare services and practice methods for the family caregivers was discussed.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.44 no.3
• /
• pp.22-32
• /
• 2021

To meet rapidly changing market demands, manufacturers strive to increase both of productivity and diversity at the same time. As a part of those effort, they are applying flexible manufacturing systems that produce multiple types and/or options of products at a single production line. This paper studies such flexible manufacturing system with multiple types of products, multiple Bernoulli reliability machines and dedicated buffers between them for each of product types. As one of the prevalent control policies, priority based policy is applied at each machines to select the product to be processed. To analyze such system and its performance measures exactly, Markov chain models are applied. Because it is too complex to define all relative transient and its probabilities for each state, an algorithm to update transient state probability are introduced. Based on the steady state probability, some performance measures such as production rate, WIP-based measures, blocking probability and starvation probability are derived. Some system properties are also addressed. There is a property of non-conservation of flow, which means the product ratio at the input flow is not conserved at the succeeding flows. In addition, it is also found that increased buffer capacity does not guarantee improved production rate in this system.