• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.10
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• pp.79-85
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• 2009

The design of a 3.2 Gb/s serial link receiver in $0.18{\mu}m$ CMOS process is presented. The major factors limiting the performance of high-speed links are transmission channel bandwidth, timing uncertainty. The design uses a multi-level signaling(4-PAM) to overcome these problems. Moreover, to increase data bit-rate and lower BER, we designed this circuit by using a current mode amplifier, Current-mode Logic(CML) sampling latches. The 4-PAM receiver achieves 3.2 Gb/s and BER is less than $1.0\;{\times}\;10^{-12}$. The $0.5\;{\times}\;0.6\;mm^2$ chip consumes 49 mA at 3.2 Gb/s from a 1.8-V supply.

• Journal of Korea Trade
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• v.25 no.6
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• pp.78-104
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• 2021

Purpose - Semiconductors are a significant export item for Korea that is expected to continue to contribute significantly to the Korean economy in the future. Thus, the semiconductor industry is a critical component in the 4th Industrial Revolution and is expected to continue growing as the non-face-to-face economy expands as a result of the COVID-19 pandemic. In this context, this paper aims to empirically investigate how semiconductors are imported and exported in Korea from a global supply chain perspective by analysing import and export data at the micro-level. Design/methodology - This study conducts a multifaceted analysis of the global supply chain for semiconductors and related equipment in Korea by examining semiconductor imports and exports by semiconductor type, year, target country, mode of transportation, airport/port, and domestic region, using import/export micro-data. The visualisation, flow analysis, and Bayesian Network methodologies were used to compensate for the limitations of each method. Findings - Korea is a major exporter of semiconductor memory and has the world's highest competitiveness but is relatively weak in the field of system semiconductors. The trade deficit in 'semiconductor equipment and parts' is clearly growing. As a result, continued investment in 'system semiconductors' and 'semiconductor equipment and parts' technology development is necessary to boost exports and ensure a stable supply chain. Originality/value - Few papers on semiconductor trade in Korea have been published from the perspective of the global supply chain or value chain. This study contributes to the literature in this area by focusing on import and export data for the global supply chain of the Korean semiconductor industry using a variety of approaches. It is our hope that the insights gained from this study will aid in the advancement of SCM research.

• Food Science and Preservation
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• v.3 no.1
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• pp.61-75
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• 1996

Apple is most favorable fruit in Korea, and apple farmland has been increased before and after the agreements of Uruguay Round and apple is considered as one of strategic agricultural products. Especially expansion of apple farmland is concentrated in Kyungpook region because of the suitable climate and its market share is about 70 percents in 1992. The marketing channels of apples of Kyungpook region are widely classified by merchant, agricultural or horticultural co-op and large scale farmer's. Among them market share of merchant's occupy over 65 percent. In marketing margins, commercial profit is higher than cost in total marketing margins and, assembler and retailer's margin is not less than wholesaler's. The fluctuation of the price of apple is high in year. The marketing problems of apples are several, first, complex marketing channels, secondly, the high percentage of market share by growing district assembler, thirdly, low rate of package and quality standardization, finally, concentration of shipment of apple because of the shortage of apple processing, storage and marketing facilities, of newly produced apples. In conclusion, to increase apple grower's income with the stabilization of supply and quality upgrade, the improvement measures of marketing system are as follows, first, government level's support in marketing facilities and mechanism, secondly, the increment of supply by grower's cooperatives, thirdly, the establishment of a serious of marketing system to increase the efficiency, fourthly, the establishment of cold-chain system and quality standardization of apple, finally, production of various kinds of apple processing goods.

• Research in Community and Public Health Nursing
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• v.10 no.2
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• pp.422-434
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• 1999

The purpose of this study was to describe the degree of satisfaction at day care center's services and the degree of relationship between each service and overall satisfaction. The data collection was performed from July 1, 1999 to July 15, 1999. And total 199 elderly clients were interviewed in Koksung-kun. The results of the study is as follows: 1. The percentage of satisfactory response at transport service was 95.2%, food supply 94.3%, bath 93.2%, hair cutting 90.8%, physical therapy 90.2%, medical treatment 89.3%. And oriental medical treatment 82.0%. 2. For question of the degree of satifaction at day care service, the distribution of answer was 75.1% in exellent. 15.5% in good, 3.6% in moderate, 3.6% in poor, 2.1% in most poor. 3. The subjective satisfaction was not significantly different by sex, age, the presence or absence of religious, educational level, the presence or absence of family and economic level. 4. A significant association between the program satisfaction and the subjective satisfaction was observed: odds ratios were 26.9 in food supply, 26.4 in luncheon supply, 17.4 in bath, and 14.5 in hair cutting. The following is suggestion based on results of this study: A service program should be developed to fit conditions of rural elderies by specifically analyzing needs of the elderly.

• Journal of Korean Society on Water Environment
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• v.38 no.6
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• pp.275-281
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• 2022

To maintain water quality after water treatment, monitoring whether the quality of treated tap water quality changes is essential. However, current investigations are insufficient to prevent secondary contamination in drinking water supply systems. This study investigated Gyeonggi's e apartment where a red water problem occurred and monitored the water quality and corrosiveness of the overall water supply system to the apartment from June 2021 to April 2022. In a comparison of drinking water quality after water treatment and the influent of the reservoir, turbidity and heavy metal concentrations were increased and residual chlorine was decreased due to increases in temperature. Correlation analysis and principal component analysis (PCA) indicated that a low level of residual chlorine may cause the abscission of Mn²⁺ and Fe²⁺ through microorganism activation, which also causes a high level of turbidity. The corrosion index (LI) in the influent of the reservoir tank was increased due to Ca²⁺ and temperature. These results indicate that the corrosiveness of drinking water and the deterioration of drinking water quality were mainly increased between the drinking water treatment plant and the reservoir tank's influent. The findings provide clear evidence that it is essential to manage water supply systems and reservoir tanks to prevent the secondary contamination of drinking water.

• Journal of Korean Society of Water and Wastewater
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• v.37 no.6
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• pp.363-373
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• 2023

Numerous studies have established a correlation between sociodemographic characteristics and water usage, identifying population as a primary independent variable in mid- to long-term demand forecasting. Recent dramatic sociodemographic changes, including urban concentration-rural depopulation, low birth rates-aging population, and the rise in single-person households, are expected to impact water demand and supply patterns. This underscores the necessity for operational and managerial changes in existing water supply systems. While sociodemographic characteristics are regularly surveyed, the conducted surveys use aggregate units that do not align with the actual system. Consequently, many water demand forecasts have been conducted at the administrative district level without adequately considering the water supply system. This study presents an upward water demand forecasting model that accurately reflects real water facilities and consumers. The model comprises three key steps. Firstly, Statistics Korea's SGIS (Statistical Geological Information System) data was reorganized at the DMA level. Secondly, DMAs were classified using the SOM (Self-Organizing Map) algorithm to consider differences in water facilities and consumer characteristics. Lastly, water demand forecasting employed the PCR (Principal Component Regression) method to address multicollinearity and overfitting issues. The performance evaluation of this model was conducted for DMAs classified as rural areas due to the insufficient number of DMAs. The estimation results indicate that the correlation coefficients exceeded 0.9, and the MAPE remained within approximately 10% for the test dataset. This method is expected to be useful for reorganization plans, such as the expansion and contraction of existing facilities.

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.5
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• pp.423-429
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• 2013

A 6-Gb/s differential voltage mode driver is presented whose output impedance and pre-emphasis level can be controlled independently. The voltage mode driver consists of five binary-weighted slices each of which has four sub-drivers. The output impedance is controlled by the number of enabled slices while the pre-emphasis level is determined by how many sub-drivers in the enabled slices are driven by post-cursor input. A prototype transmitter with a voltage-mode driver implemented in a 65-nm CMOS logic process consumes 34.8-mW from a 1.2-V power supply and its pre-emphasized output signal shows 165-mVpp,diff and 0.56-UI eye opening at the end of a cable with 10-dB loss at 3-GHz.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.8
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• pp.54-61
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• 2001

A fully on-chip open-drain CMOS output driver was designed for high bandwidth DRAMs, such that its output voltage swing was insensitive to the variations of temperature and supply voltage. An auto refresh signal was used to update the contents of the current control register, which determined the transistors to be turned-on among the six binary-weighted transistors of an output driver. Because the auto refresh signal is available in DRAM chips, the output driver of this work does not require any external signals to update the current control register. During the time interval while the update is in progress, a negative feedback loop is formed to maintain the low level output voltage ($V_OL$) to be equal to the reference voltage ($V_{OL.ref}$) which is generated by a low-voltage bandgap reference circuit. Test results showed the successful operation at the data rate up to 1Gb/s. The worst-case variations of $V_{OL.ref}$ and $V_OL$ of the proposed output driver were measured to be 2.5% and 7.5% respectively within a temperature range of $20^{\circ}C$ to $90^{\circ}C$ and a supply voltage range of 2.25V to 2.75V, while the worst-case variation of $V_OL$ of the conventional output driver was measured to be 24% at the same temperature and supply voltage ranges.

• Journal of Internet Computing and Services
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• v.15 no.2
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• pp.95-107
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• 2014

This study was conducted to empirically examine the impact of fit between project radicalness and innovativeness of the supply chain on the degree of supply chain integration. In order to test the research hypotheses, a survey was employed. The results show that the degree of supply chain integration varies on the fit between project radicalness and innovativeness of the supply chain. Specifically, when a supply chain consists of two morphogenetic organizations and the supply chain integration project is radical, we see very highly integrated supply chain. We also find high-level integration of supply chain when project is radical even though both a morphogenetic and a homeostatic organization compose a supply chain. However, we find opposite result, which is low integration, if a project is incremental rather than radical and a supply chain is composed of same types of the organizations mentioned above. Interestingly, degree of integration seems to be always low when a supply chain is composed of two homeostatic organizations, regardless of project radicalness. With these findings, this study concludes that a project whose radicalness is match with the supply chain's innovativeness should be chosen for successful supply chain integration.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.77-82
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• 2006

Integrity plays a fundamental role in the feasibility of 'liability critical' applications. Road charging, e.g. road tolling in urban zones or on highways, represents a series of liability critical applications where a guarantee in integrity could be a true enabler: being the mechanism that prevents the incorrect charging of users and enabling the advancement of these applications using GNSS such as Galileo and EGNOS that provide integrity mechanisms. However, the integrity of the end user position is not guaranteed by the EGNOS and Galileo integrity services alone as provided. Algorithms have been developed to supply a guarantee on the performance attainable at the user level through the provision of a horizontal protection level that responds to local user conditions such as multipath or interference. In addition, an application has been developed that implements road charging mechanisms based on the availability of user-level integrity. Results obtained show that the user-level integrity algorithms provided the required level of integrity guarantee and granularity of the horizontal protection levels necessary for executing urban and rural (highway) road charging. In addition, the road charging application developed shows that the current application domain requirements can be met through the provision of guaranteed integrity and that further reductions in the horizontal protection levels along with increased signal availability will enable future road charging modalities.