• Journal of Korean Port Research
• /
• v.14 no.1
• /
• pp.1-11
• /
• 2000

Recently, the role of container ports is radically changing, These changes are largely driven by the innovation process of Logistics such as Supply Chain Logistics and Global Logistics due to the international expansional of industry. Under this environment, It is required that the container port should act as a integral part of a Supply Logistics Chain especially to provide the customer-oriented logistics service. This paper deals with the development strategy of container ports coping with these changes in the view point of container ports as a Logistics infrastructure to provide customer-response services and necessary to the economic promotion of hinterlands. Strategy is suggested in the phases of the customers desire, the pattern of container cargo, the economic promotion of hinterlands, and interrelation of container ports in north-east Asia and also domestics through the analysis of competiveness of container ports.

• Journal of Korean Society for Quality Management
• /
• v.30 no.3
• /
• pp.66-78
• /
• 2002

Process capability indices are being used as indicators for measurements of process capability for SPC of quality assurance system in industries. In view of the enhancement of customer satisfaction, process capability indices in which loss functions are used to deal with the economic loss In the processes deviated from the target, are in an adequate representation of the customer's perception of quality In this connection, the loss function has become increasingly important in quality assurance. Taguchi uses a modified form of the quadratic loss function to demonstrate the need to consider the proximity to the target while assessing its quality. But this traditional quadratic loss function is inadequate to assessing the quality and quality improvement since different processes have different sets of economic consequences on the manufacturing, Thereby, a flexible approach to the development of the loss function needs to be desired. In this paper, we introduce an easily understood loss function, based on reflection of probability density function of the normal distribution. That is, the Reflected Normal Loss function can be adapted to an asymmetric loss as well as to a symmetric loss around the target. We propose that, instead of the process variation, a new capability index, CpI using the Reflected Normal Loss Function that can accurately reflect the losses associated with the process and a new capability index CpI Is compared with the classical indices as $C_{p}$ , $C_{pk}$, $C_{pm}$ and $C_{pm}$ $^{+}$.>.+/./.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.21 no.5
• /
• pp.889-902
• /
• 1997

During the past three decades, there have been drastic changes in many fields in Korea. Social and economic changes which occurred meantime have influenced clothing expenditures of Korean consumers. The purpose of this study was to investigate the change of clothing expenditures and its determinants in Korea during the period of 1965 to 1993. In particular, the impacts of income and price on clothing expenditures were examined using data from the National Acccounts published by the Bank of Korea as well as Urban Household Economy Survey published by the Bureau of National Statistics. Per-person consumption expenditures for clothing and shoes (CSX) in permanent price generally increased in accordance with the increase of income since 1965. From 1978 to 1984, however, there was a slight decrease in clothing expenditures in spite of the continuous increase in income, due to the depression of national economy. The proportion of CSX in total consumer spendings has decreased continuously since 1978. In recent years, CSX take only 5% of national aggregate consumption expenditures, while consumption expenditures of urban consumers is 8%. The expenditures for traditional clothing and fabrics for home- sewing decreased most. The results of this study should provide a broader view of the pattern of clothing consumption by Korean consumers. Moreover, the findings can suggest how social and economic changes of a society affect consumers' clothing expenditures.

• Economic and Environmental Geology
• /
• v.30 no.5
• /
• pp.469-476
• /
• 1997

In the conventional velocity analysis, the peaks of a semblance panel are picked and the stacking velocities of the peaks are assumed as RMS velocities from which interval velocities are determined. This velocity analysis technique is correct only for horizontal homogeneous layes and incurs error in a layer whose velocity varies laterally. Tediousness of peak picking and error in velocity analysis can be reduced by automatic velocity analysis techniques. An automatic velocity analysis algorithm has been presented in order to improve these problems by considering the stacking velocity from the view point of interval velocity model and by relating the stacking velocity and the interval velocity with the traveltimes. In this paper, we apply the automatic velocity analysis method to simple models having lateral velocity anomaly to verify the effectivenesses and limits of this method. From the results of numerical experiments, we can determine the interval velocites without pickings of the stacking velocities in the one-dimensional velocity analysis and the general patterns of the laterally varying interval velocities appear in the two-dimensional case. However, the interval velocity and the depth of velocity anomaly determined by two-dimensional automatic velocity analysis are somewaht discrepant in those of the theoretical model.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.12 no.1
• /
• pp.157-157
• /
• 1987

Hydro-electric power generation from multi-purpose dams has been playing important roles in the electric power supply network in Korea. Although the total share of hydro power in national electricity supply now becomes very small, the peak-shaving and frequency control capability of hydro power helps the power company enormously in maintaining the quality of power. But since the company that builds and operates the multi-purpose dams in Korea has to sell all the electricity produced to the monopolistic utility, there have been various problems in justifying the investment, designing pricing mechanism, and controlling operations of the power plants. In addition, economic evaluation of the hydro power has been distorted by a variety of reasons and hence it has been very difficult to encourage effective development and utilization of national water resources. To make the problem worse, both parties are public companies with X-inefficiency problems. Thus, changing environment requires to reengineer the system that governs hydro power generation. We address the problems of Korean hydro-electric power generation system in four areas: the investment justification process, the operations decison right of the hydro power plants, the pricing of the purchased-power, and the negotiation of contract revision. Then we propose improvement directions of new hydro-electric power system in view of static and dynamic efficiency, X-inefficiency and equity.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.67 no.11
• /
• pp.1415-1422
• /
• 2018

In Korea, prior to 2011, the electric reserve margin followed the probabilistic reliability view and the planning reserve margin had been operated at about 15% based on the assumption that power outage was permitted within 0.5 days a year. However, after experiencing the shortage of the electric generation capacity in Sept. 15, 2011, the planning reserve margin was selected as 22% to improve the reliability of the electric supply. In this paper, using panel data of 28 OECD countries over the period 2000-2014 we attempted to empirically examine the linkage between reserve margin, electricity tariffs, renewable energy share, GDP per capita, and summer / winter peak-to-peak ratios. As a result, all four independent variables have been significant for the electric reserve margin, and in particular, we found that countries with similar peaks in winter and summer have operated 4.3% higher reserve margin than countries experiencing only summer peak.

• Korean Management Science Review
• /
• v.12 no.1
• /
• pp.157-173
• /
• 1995

Hydro-electric power generation from multi-purpose dams has been playing important roles in the electric power supply network in Korea. Although the total share of hydro power in national electricity supply now becomes very small, the peak-shaving and frequency control capability of hydro power helps the power company enormously in maintaining the quality of power. But since the company that builds and operates the multi-purpose dams in Korea has to sell all the electricity produced to the monopolistic utility, there have been various problems in justifying the investment, designing pricing mechanism, and controlling operations of the power plants. In addition, economic evaluation of the hydro power has been distorted by a variety of reasons and hence it has been very difficult to encourage effective development and utilization of national water resources. To make the problem worse, both parties are public companies with X-inefficiency problems. Thus, changing environment requires to reengineer the system that governs hydro power generation. We address the problems of Korean hydro-electric power generation system in four areas: the investment justification process, the operations decison right of the hydro power plants, the pricing of the purchased-power, and the negotiation of contract revision. Then we propose improvement directions of new hydro-electric power system in view of static and dynamic efficiency, X-inefficiency and equity.

• Computers and Concrete
• /
• v.18 no.1
• /
• pp.53-68
• /
• 2016

In this study, an investigation is made from the statics and economic aspects of the possibility of using the composite material ferrocement on the surfaces of squat cylindrical grain silos. For this purpose, the geometry of two model silos, each of height 5 m and diameter 5 m and 12.5 m, was designed. Five different reinforced plates of 10 and 20 mm thickness were produced to research the most suitable ferrocement plates to be used on the surface of these silos. Most durable reinforcement type for covering the silo surface was determined by pressure and bending tests. Grade 30 and Grade 55 steel plates were also considered for use in covering steel-coated silos. In the statics analysis performed with SAP2000, the least plate thicknesses needed for silos surfaced with Grade 30 and Grade 55 steel were found to be 6.20 mm and 4.70 mm respectively for silos of diameter 5 m, and 6.70 mm and 5.00 mm for silos of diameter 12.5 m. In the economic analysis, it was found that 20 mm thick Type 4 (with a wire diameter of 0.30 mm and a mesh aperture of $2mm{\times}2mm$ square type) reinforced ferrocement surfacing material was 5.6-6.1 times more economical than Grade 30 steel surfacing material and 4.4-4.7 times more economical than using Grade 55 steel. These results show that ferrocement can be used in place of steel from the point of view both of statics and economy.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2004.04a
• /
• pp.413-419
• /
• 2004

In these days, 8,000TEU container ship service launches in shipping service at latest based on the economy of scale, unit cost related with ship operation on ocean decreases in proportion to increase of ship scale and mega ship over 10,000TEU is on planning. Most of the exiting researches have performed from the perspective of total operation cost from mega port to mega port. However, the purpose of this paper is to estimate economic efficiency by ports selected Hub port from total cost point of view, operation cost, port charge, feeder cost, etc.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.40 no.3
• /
• pp.111-116
• /
• 2014

Objectives: Dislocation of the temporomandibular joint may occur for various reasons. Although different invasive methods have been advocated for its treatment, this study highlights the value of non-invasive treatment options even in chronic cases in a resource-poor environment. Materials and Methods: A seven-year retrospective analysis of all patients managed for temporomandibular joint dislocation in our department was undertaken. Patient demographics, risk factors associated with temporomandibular joint dislocation and treatment modalities were retrieved from patient records. Results: In all, 26 patients were managed over a seven-year period. Males accounted for 62% of the patients, and yawning was the most frequent etiological factor. Conservative treatment methods were used successfully in 86.4% of the patients managed. Two (66.7%) of the three patients who needed surgical treatment developed complications, while only one (5.3%) patient who was managed conservatively developed complications. Conclusion: Temporomandibular joint dislocation appears to be associated with male sex, middle age, yawning, and low socio-economic status, although these observed relationships were not statistically significant. Non-invasive methods remain an effective treatment option in this environment in view of the low socio-economic status of the patients affected.