• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.10 s.352
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• pp.1-7
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• 2006

Lattice decoding concept has been proposed for the implementation of the Maximum-Likelihood detection which is the optimal receiver from the viewpoint of the BER (Bit Error Rate) performance for MIMO (Multiple Input Multiple Output) systems. Sphere decoding algorithm and K-best decoding algorithm are based on the lattice decoding concept. A K-best decoding algorithm shows a good BER performance with relatively low complexity. However, with small K value, the error propagation effect severely degrades the performance. In this paper, we propose an adaptive K-best decoding algorithm which has lower average complexity and better BER performance than conventional K-best decoding algorithm.

• Proceedings of the KIEE Conference
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• 2002.11c
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• pp.35-38
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• 2002

In this paper, the design of explicit rate-based congestion control in high speed communication networks is considered. The goal of congestion control is to achieve high link utilization, low packet loss, low delay, and fairness among the best-effort sources. To deal with the propagation delays associated with the best effort sources, An MPC technique is employed to solve the congestion problem[1] here. However, the problem with this method is that the closed loop performance relies highly on the knowledge of average service rate. This paper focuses on coping with the problem described above by using a CARIMA model for service rate(available rate).

• Journal of electromagnetic engineering and science
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• v.12 no.1
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• pp.8-12
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• 2012

In this paper, we evaluate performances of dual-hop decode-and-forward relaying systems with the $N^{th}$ best-relay selection scheme. In some schemes, such as scheduling or load balancing schemes, the best relay is unavailable and hence the system must resort the second best, third best, or generally the $N^{th}$ best relay. We derive the expressions of the outage probability and symbol error rate (SER) for this scenario over Rayleigh fading channels. Monte-Carlo simulations are presented to verify the analytical results.

• IE interfaces
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• v.10 no.2
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• pp.57-67
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• 1997

This paper is a report of a simulation study that investigates a dynamic approach to scheduling jobs in a conventional shop floor, especially in an assemoly-type welding process. We consider both JIT arrival and JIT delivery. Various dispatching rules are tested for the following performance measures; mean flow time, rate of tardy jobs, mean tardiness, sum of mean tardiness and mean earliness. The results indicate that SPT rule is the best for the mean flow time. MSLACK that we suggest in this paper, is the best for the mean tardiness and the sum of mean tardiness and mean earliness. However, it is not clear that which rule is the best for the rate of tardy jobs.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.6
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• pp.140-146
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• 2013

This experiment was conducted in order to study the physiological characteristics of Sedum takevimense in different moisture conditions. The photosynthetic rate, water use efficiency and the respiratory rate were determined by using a photable photosynthesis system. According to the results, the best illumination range and moisture range were explicitly selected. The highest photosynthetic rate was at $600{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, and after this value, the trend showed a reduction. When the moisture was 11.31%, the photosynthetic capacity and water use efficiency reached maximum value, but the respiratory rate reached maximum value at 7.91%. According to the measured values, the best illumination range was $600{\sim}1,200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and the best moisture range was 7.09~11.31%.

• Journal of Korean Society for Quality Management
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• v.41 no.4
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• pp.555-566
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• 2013

Purpose: The purpose of this study is to develop innovation index of hospital service integrating 6 sigma and SERVQUAL. Methods: This study used DMA(Define, Measure and Analysis) from 6 sigma and 5 Factors from SEVQUAL. To test data, chi-squire text, association analysis and behavior analysis was conducted. Results: This study indicated the management index through CTQ (Critical to Quality) and Chosen few X using 6 sigma process. Finally, And this study developed 5 Factors; Equipment Utilization in Tangibility, Ratio of Patients/Disease/Behavior/Treatment in Reliability, Survival RAte, Canselation Rate of Reservation, Churn Rate, Interval of Treatment and Confidence in Responsiveness, Frequency of Patients/Disease/Behavior/Treatment in Assurance and Contrast to Best Department/Best Doctor/Best Doctor in Faculty/Average of Mine in Empathy. Conclusion: This study developed innovation index of hospital service. Managing this index, hospital is able to achieve the decline of total treatment cycle, adjustment of patients behavior and increase of equipment utilization. Ultimately, hospital is able to accomplish innovation of healthcare service.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.4
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• pp.16-26
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• 1999

Five soil mixture with seven turfgrass species when placed over a plastic sheet were evaluated for influence on covering rate, visual rating, visual color and sad development. The result were as follows. 1. The last covering rate was high on sand+bark and on Kentucky bluegrass, respectively while the early covering rate was high on sand+peat and on perennial ryegrass and tall fescue. respectively. 2. Both sand and sand+sandy loam caused poor effects on the covering rate and the visual rating. 3. The early growth was good on perennial ryegrass but the covering rate and the visual rating gradually turned poor because of summer drought. 4. Visual color was high on sand+bark and on Kentucky bluegrass, respectively. 5. Covering rate, visual rating and visual color was best evaluated on Kentucky bluegrass during winter. 6. Sad was highly developed on sand+bark and sand+peat as compared with on the other soil mixture. 7. The carpet-type sad was best developed on Kentucky bluegrass.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.829-844
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• 2020

A vacuum metering device for garlic seeds was developed, and its metering performance was tested according to the design factors. Three design factors were as follows: suction surface diameter (Edge), suction surface curvature (Type), and guide height (Guide). The suction surface curvature represents the distance between the center of the grooved suction plate and the bottom of suction plate. The metering rate and multiple metering rate were analyzed as the metering performance of the developed device with two varieties of garlic seeds: Namhae (warm region-adapted garlic) and Uiseong (cold region-adapted garlic). The best metering performance for the Namhae seeds were found with the following conditions: An Edge, Guide and Type of 40, 4, and 35 mm, respectively. In the case of the Uiseong seeds, the best conditions were as follows: An Edge, Guide and Type of 35, 4, and 30 mm, respectively. The guide height was found to be the most influential design factor on the metering performance of the metering rate and multiple rate for both Namhae seeds and Uiseong seeds. Additionally, the interaction between the area of the suction surface and the curvature of the suction surface had some effects on the multiple rate for the Uiseong seeds. It was concluded that the guide height should be 4 mm or higher so that more than 90% of the metering rate could be achieved for the tested garlic seeds with the developed metering device.

• The Transactions of the Korea Information Processing Society
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• v.7 no.5S
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• pp.1599-1608
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• 2000

Automated collaborative filtering is on the verge of becoming a popular technique to reduce overloaded information as well as to solve the problems that content-based information filtering systems cannot handle. In this paper, we describe three different algorithms that perform collaborative filtering: GroupLens that is th traditional technique; Best N, the modified one; and an algorithm that uses clustering. Based on the exeprimental results using real data, the algorithm using clustering is compared with the existing representative collaborative filtering agent algorithms such as GroupLens and Best N. The experimental results indicate that the algorithms using clustering is similar to Best N and better than GroupLens for prediction accuracy. The results also demonstrate that the algorithm using clustering produces the best performance according to the standard deviation of error rate. This means that the algorithm using clustering gives the most stable and the best uniform recommendation. In addition, the algorithm using clustering reduces the time of recommendation.

• Advances in aircraft and spacecraft science
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• v.2 no.4
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• pp.469-482
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• 2015

This study has the aim to develop a numerical design regarding the position and the inner performances of a heat exchanger in a light helicopter. the problem was to find first of all the best position of the heat exchanger inside the engine vane in order to maximize the air flow rate capable to pass through the heat exchanger section. It is to be said that the only air contribution in the vane comes from the opening present in the roof under the main rotor. The design has been performed by means of the commercial code Fluent and using the well known grid generator ICEM CFD. Different positions are first investigated so to establish the best one. Subsequently, different areas of the opening on the roof have been considered in order to maximize even more the flow rate in the heat exchanger that was not sufficient based on the first guess of velocity, as aforementioned. At the end interesting design results are presented and discussed by contours of fields and values.