• The Transactions of the Korea Information Processing Society
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• v.6 no.11S
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• pp.3269-3277
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• 1999

To promote the inclusion of end-to-end congestion control in the design of future protocols using best-effort traffic, we propose a router mechanism, Extended FRED(ex-FRED). In this paper, we catagorize the TCP controlled traffics into robust and fragile traffic and discuss several unfairness conditions between them caused by the diverse applications. For example, fragile traffic from bursty application cannot use its fair share due to their slow adaptation. Ex-FRED modifies the FRED(Fair Random Early Drop), which can show wrong information due to the narrow view of actual buffer. Therefore, Ex-FRED uses per-flow accounting in larger virtual buffer to impose an each flow a loss rate that depends on the virtual buffer use of a flow. The simulation results show that Ex-FRED uses fair share and has good throughput.

• Proceedings of the IEEK Conference
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• 2002.06a
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• pp.81-84
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• 2002

The WRR scheduling algorithm is widely used in ATM networks due to its simplicity and the low cost of hardware implementation. It guarantees minimum cell rate according to the weight of each queue. The fairness is a important factor for ABR service. That is, Scheduling algorithm allocates network resources fairly to each VC. In this paper, we propose a scheduling algorithm for satisfying the two fairness criteria, MCR plus equal share and Maximum of MCR or Max-Min share, among the six criteria defined by ATM Forum TM 4.1 specification. The WRR, Nabeshima et al, and the proposed scheduling algorithms are compared with respect to fairness and convergence time throughout experimental simulation.

• Journal of Information Science Theory and Practice
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• v.2 no.1
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• pp.22-34
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• 2014

This paper analyzes India's contribution to world tribology research during the period 2001-2012 based on SCOPUS records. India's global publication share, annual output, and its citation impact of Indian contribution, partner countries, leading contributors, leading institutes, and highly cited papers were analyzed. Additionally, a cloud technique is used to map frequently used single words in titles. It is observed that India ranks in the $7^{th}$ position with a global publication share of 3.83% and an annual average growth rate of 25.58% during the period 2001-2012. The citation impact of India's contribution is 6.05 which decreased from 12.74 during 2001-2006 to 4.62 during 2007-2012. 17.4% of India's total research output was published with international collaboration.

• Journal of the Korea Society of Computer and Information
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• v.7 no.1
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• pp.154-160
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• 2002

Global cosmetic corporations take about 40% of Korean cosmetic market in a short period, and will expand their share rate. Furthermore, Korean main cosmetic market channel has been changed from cosmetic shop to diverse channels in accordance with Korean consumer's trends. Therefore, Korean cosmetic corporations must response to the global competitors and the changed market factors simultaneously with an effective business strategy. This paper suggests the effective business strategy to keep and raise the market share against the global cosmetic corporations, and response to the changed market situation.

• 한국정보통신설비학회:학술대회논문집
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• 2005.08a
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• pp.85-91
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• 2005

Coexistence of different wireless systems that share the 2.4 GHz ISM frequency band is becoming one of the most important issue. This paper presents a model of the interference that IEEE 802.11b may experience because of IEEE 802.15.4. The packet error rate (PER) of IEEE 802.11b under the interference of IEEE 802.15.4 is analyzed. The PER is obtained by using the bit error rate (BER) and the collision time. The analytical results are validated using simulation.

• Journal of the Korean Regional Science Association
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• v.38 no.3
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• pp.19-39
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• 2022

The aim of this study is to compare and analyze structural characteristics of smart city industry focused on Korea and Spain. Structural characteristics of industries were compared focusing on share, penetration, impact path and network clustering of smart industries. Research data used input-output tables established by Korea and Spain in 1995 and 2015, and industries were reclassified into 8 and 25 industries. The analysis model is the Smart SPIN Model. The key finding as follows: It was analyzed that there are differences in the structure and characteristics of the smart city industry between Korea and Spain. Firstly, It is analyzed that Korea has a larger share and penetration rate of IT manufacturing than Spain. On the other hands, Spain has a higher share and penetration rate in the IT service and knowledge service sectors than Korea. Secondly, Korea had many production paths for the IT service and the knowledge service. On the other hands, Spain included more production paths in the IT manufacturing sector. Thirdly, as a result of network analysis, Korea's smart industry has a characteristic that it is difficult to develop independently because it is dependent on traditional industries. In Spain, most of the smart industries were included in one industrial cluster, and it was analyzed to have an independent form. In conclusion, It was found that Korea has the industrial characteristics of a smart city based on IT manufacturing. Spain has the characteristics of smart city industry based on IT service and knowledge service. The results of this study are expected to provide basic data on the direction of smart city promotion and the establishment of smart city policies in Korea.

• Journal of the Korea Computer Industry Society
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• v.2 no.4
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• pp.547-564
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• 2001

In this paper a simulation has been performed to compare and evaluate the performance between the EPRCA(Enhanced Proportional Rate Control Algorithm) and EMRCA(Explicit Max_min Rate Control Algorithm) switches. The variation of the ACR at the source end system, the queue length, the utilization rate of the link bandwidth and the share fairness at the transient and steady states are used as the evaluation criteria for the simulation. The EMRCA switch is more stable than the EPRCA switch and reduces its buffer size. Also, it achieves a higher utilization rate of the link bandwidth than the EPRCA switch. The hardware complexity of the EMRCA switch is significantly lower than the EPRCA and other rate-based switches. Since it eliminates the necessity of the floating-point operation for calculation of the MACR(Mean Allowed Cell Rate) at the switch.

• The Journal of Industrial Distribution & Business
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• v.15 no.5
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• pp.17-27
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• 2024

Purpose: The renminbi (RMB) has appreciated alongside the elevation of China's economic status, leading to increased exchange rate volatility. Moreover, China's medical industry saw a surge in import and export trade volume, with trade related to epidemic prevention and control in the medical sector significantly increasing its share. The medical device trade, in particular, occupies a substantial portion of this trade. Research design, data and methodology: This paper focuses on the import and export value of medical devices in the medical industry as a case study to explore the impact of RMB exchange rate fluctuations on the import and export trade of the medical industry during the pandemic. Additionally, it investigates whether the import and export trade of the medical industry can be a contributing factor to the fluctuations in the RMB exchange rate. Results: Through an empirical study on the import and export values of medical devices in the medical industry over the past three years, as well as the RMB exchange rate, this paper establishes a VAR model and conducts a series of tests including stationarity tests and cointegration tests. Conclusions: The conclusion is that fluctuations in the RMB exchange rate have a long-term impact on China's medical industry's import and export trade.

• Korean Journal of Agricultural Science
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• v.31 no.2
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• pp.135-148
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• 2004

Rice is not only main food but also key farm income source of Korean farmers. In spite of the above facts, rice productivity was decreased on account of drought in every 2 or 3 years interval owing to the vulnerability of irrigation facilities throughout Korea in the past decades. As an context of the first five year economic development plan, all weather farming programme including 4 big river basin comprehensive development projects and large and medium sized irrigation water development projects were carried out successfully. Therefore the area of irrigated paddy were increased from 58% in 1970 to 76.2% in 1999. In the past decades, the Government had invested heavy financial funds to develop irrigation water but as an factor share analysis, the contribution rates of irrigation water and investment for farmland base development project have not been identified yet in national agricultural economic level. It is very scarce to find out the papers concerned to macro-economic factor share analysis or contribution rates of water and investment cost to rice production value in Korea considering the production function of the quantity of irrigation water and investment cost as independent variables. Accordingly this paper covered and aimed at identifying (1) derivation of rice production function with the time serial data from 1965 to 1999 and the contribution rates of irrigation water and total investment cost for farmland base development project. The analytical model of the contribution rates was adapted the famous Cobb-Douglass production function. According to the model analysis, the contribution rate of irrigation water to rice production in Korea was shown 37.8% which was equivalent to 0.28 of the production elasticity of water. The contribution rate of farmland base development project cost was revealed 22% and direct production cost of rice was contributed 60% in the growth of rice production and farm mechanization costs contributed to 18% of it respectively. The two contribution rates comparing with the direct production cost were small but without irrigation water and farmland base development, application of high-pay off inputs and farm mechanization might be impossible. Considering the food security and to cope with the frequent drought, rice farming and investment for the irrigation water development should be continued even in WTO system.

• Journal of Digital Convergence
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• v.14 no.12
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• pp.405-411
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• 2016

Seoul city is publishing new plans to increase modal share rate of bicycle every year, such as, maintaining bicycle related facilities. But bicycle's modal share rate in Seoul stayed same for the last decade and people are still facing difficulties using bicycle related facilities. These problems are causing bicycle usage as connecting transportation of public transit to decrease. This study looked at the high bicycle modal countries, such as, Netherlands, Germany and Japan to find applicable solutions by analyzing cases and comparing them with cases of highly populated subway station of Sindorim in Seoul. For example, in Germany and Netherlands there is bicycle-parking system to help bikers to access subway easier, in Japan there is underground bicycle parking tower to safely keep high volume of bicycles with in small space. For Seoul city to increase its modal share rate, they should look at problems from users' prospective and solve it by fixing it and improving the services, not by making more facilities.