• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1D
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• pp.29-34
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• 2008

The Korean society has been changed to the aging one. The number of elderly people has been in creasing rapidly. For their social and economic activity, more convenient transport services have to be offered. Specifically, increasing mobility is one of the most urgent policies for them. One action of the policy in Seoul has introduced low floor buses since 2003. This paper shows how low floor buses affect on passengers' boarding and alighting time through the field survey. In the analysis of the survey results it has been found that the low floor buses can reduce average boarding time by 0.8 sec, especially, by 1.1 sec (about 36%) for elderly passengers. These outcomes expect total bus operating hours as well as headways could be reduced, and operating cost and passengers' waiting time could be saved.

• Korea Trade Review
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• v.45 no.5
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• pp.141-159
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• 2020

Container terminals at Gwangyang Port are operated by three container operators: A, B and C. Ultimately, there is consensus that a single operator should operate all terminals so that economies of scale can be achieved even in the operation of the container terminal. Integration between operators has a positive effect on both operators and shipping companies. From the operator's point of view, overlapping fixed costs between operators can be unified, reducing overall costs and utilizing spare facilities. On the other hand, from the viewpoint of the shipping company, it is possible to ensure stable use of the port facilities and always allow berthing, reduce days on demurrage and ship waiting, and provide one-stop service for work. However, existing cases of operators' integration or relocation of terminals remained to estimate the expected effects of alternatives, emphasizing only the financial point of view. The port terminal is a large system, and it is important to consider that it is an aggregate of major logistics facilities and equipment. Moreover, if the estimation can be made by quantifying the expected effect, the justification of the terminals' relocation can be further emphasized. Therefore, it is very important to estimate the expected effect from the viewpoint of systemic operation. Moreover, the need for operators' integration can be further emphasized if it can be estimated through quantification of expected effects. Currently, three alternatives are considered as alternatives to the terminals' relocation, and in this study, the optimal plan was derived for the 3 alternatives by the linear planning model of the minimum shuttle transportation cost in the terminal. The optimal plan is alternative 2, which shows the most advantageous integration effect in terms of expected effects. Alternative 2 integrates the B terminal into the C terminal, and the A terminal operates independently as it is.

• The korean journal of orthodontics
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• v.30 no.6 s.83
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• pp.677-685
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• 2000

Anchorage plays an important role in orthodontic treatment. Because of limited anchorage Potential and acceptance problems of intra- or extraoral anchorage aids, endosseous implants have been suggested and used. However, clinicians have hesitated to use endosseous implants as orthodontic anchorage because of limited implantation space, high cost, and long waiting period for osseointegration. Titanium miniscrews and microscrews were introduced as orthodontic anchorage due to their many advantages such as ease of insertion and removal, low cost, immediate loading, and their ability to be placed in any area of the alveolar bone. In this study, a skeletal Class II Patient was treated with sliding mechanics using M.I.A.(micro-implant anchorage). The maxillary micro-implants provide anchorage for retraction of the upper anterior teeth. The mandibular micro-implants induced uprighting and intrusion of the lower molars. The upward and forward movement of the chin followed. This resulted in an increase of the SNB angle, and a decrease of the ANB angle. The micro-implants remained firm and stable throughout treatment. This new approach to the treatment of skeletal Class II malocclusion has the following characteristics . Independent of Patient cooperation. . Shorter treatment time due to the simultaneous retraction of the six anterior teeth . Early change of facial Profile motivating greater cooperation from patients These results indicate that the M.I.A. can be used as anchorage for orthodontic treatment. The use of M.I.A. with sliding mechanics in the treatment of skeletal Class II malocclusion increases the treatment simplicity and efficiency.

• Journal of Korean Society of Transportation
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• v.30 no.1
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• pp.149-159
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• 2012

The evaluation of public transit service quality is more complicated than evaluating other aspects of transportation service. Although various measures of effectiveness [MOEs] for transit service have been studied and applied, a more comprehensive and accurate MOE is still required. In the past, either data from user surveys or the experience of bus agency administrators and/or engineers used to measure the quality of service. However, recently, with reliable and accurate real time data from BMS(Bus Management System) and BIS(Bus Information System), more reliable and accurate MOEs are available. This study develops a service evaluation model from users' perspectives, which is based on user' cost models that consider passenger access time, riding time, waiting time, and discomfort due to in-vehicle overcrowding, violation of traffic laws, and accident rate. For validating proposed model, data from the BMS and transit-fare cards (T-Money Card) for Seoul's No. 472 main bus line were used. Models developed in this study provided reliable results.

• The Journal of Fisheries Business Administration
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• v.14 no.2
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• pp.15-68
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• 1983

From the economic point of view the fishing port is the complex of installations on land, organized to serve the fishing fleet and its cargo, and is the main link in the production chain of all components of the fishing industry, with the aim of achieving the planned targets with the minimum cost. Fishing port investment decisions have had significant impact on the development aims of Korean fisheries. Fishing port investments in Korea are made mostly by public or semipublic port authorities. Such investments should be judged not purely on the basis of financial profitability but rather on the extent to which they serve the development aims of the fishing industry. This makes the economic appraisal process more complex and presents certain problems in correctly quantifying the economic costs and benefits of the fishing port projects. This study concentrates more on the theoretical economic appraisal models than on the purely financial aspects of fishing port investments and points out the difference between the two approaches. In the result, there is clearly an element of judgment as to whether or not a shadow price needs to be used in estimating economic benefits and costs. From this viewpoint, some attempts are made to provide definitions of the possible economic benefits and costs, and methods for estimating and evaluating them in Part III and IV. Especially queueing theory is applied in the calculation of economic benefits. When a project is contemplated and analysis shows it to Lave a positive NPV, one question that arises is whether it should be implemented now or delayed. In this paper, the first year rate of return method is regarded as a more concise way of solving the timing of investment, At the end of Part IV, risk analysis of fishing port investments is considered. It can be handled in a number of ways, ranging from informal judgment to complex statistical analyses involving large-scale computer models, This paper recommends that evaluators of fishing port investments use the sensitivity analysis indicating exactly how much NPV will change in response to a given change in an input variable, other things held constant. Decisions regarding the amount of capacity to provide must be made in fishing port investments. Providing too much service would involve excessive capital costs. On the other hand, not providing enough service capacity would cause the waiting line of fishing vessels to become excessively long at times. Therefore, in Part V, the optimal number of berths and berth productivity in fishing port are defined as follows: Minimize E(TC) ＝ E(WC)＋E(SC) The minimum of this function is the solution and that is the optimal number of berth and berth productivity in fishing port.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.4
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• pp.585-592
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• 2016

This study was conducted to analyze the gap between importance and satisfaction of university foodservice attributes as well as to assess customer satisfaction with university foodservice establishments. All statistical analyses were conducted using the SPSS package program (ver. 20.0) for t-test, ANOVA, and Importance-Performance Analysis (IPA). A total of 619 valid responses were used for the data analysis. The results of this study are as follows: the composition of respondents was 53.5% males and 46.5% females. Exactly 85.5% of respondents ate lunch at least five times a week at the on-campus foodservice. The favorite lunch menus of Chinese university students were Chinese food (91.8%), followed by Western food (3.5%), Korean food (2.2%), and Japanese food (1.5%). According to the results of IPA, foodservice selection attributes that were priorities for improvement were food taste, food freshness, menu variety, waiting time for meal, and toilet cleanliness. In addition, five satisfaction factors were extracted by exploratory factor analysis. According to the results of one-way ANOVA, 'physical environment' and 'service quality' factors showed significant differences according to the students' grades and the frequency of eating lunch at on-campus foodservice. On the other hand, 'food quality and menu' and 'convenience and price' factors showed significant differences according to meal cost. In conclusion, in order to enhance customer satisfaction of on-campus foodservice, foodservice managers should offer a varied menu at reasonable prices and improve food quality.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.6
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• pp.2225-2233
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• 2010

Current puretone audiometer takes an operation model, so called face-to-face model, in which model an audiometrist assesses only one subject at a time. Such model results in high cost and long waiting time when there exist many patients. In order to solve such a disadvantage of face-to-face model, we have developed PC-based audiometer supporting client/server model, in which model one audiometrist is able to measure several subjects concurrently. This model has an architecture like that several PCs for subjects are connected to an audiometrist's PC through LAN and each assessment process of subjects are displayed onto audiometrist's monitor in real time. And if necessary, it makes possible for audometrist to adjust the assessment progress of particular subject like as a face to face model.

• Journal of Korean Society of Transportation
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• v.22 no.7 s.78
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• pp.107-117
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• 2004

The growing demand for customer-response, made-to-order manufacturing and satisfactory delivery are stimulating the importance of commercial fleet management problem. Moreover, the rapid transformation to the customer-oriented multi-frequency, relatively small fleet, such as home delivery and Perishable goods, requiring prompt delivery and advanced real-time operation of vehicle fleets. In this paper we consider the vehicle routing problem(VRP) to minimize delivery completion time which is equal to the time that last customer wait for the vehicle in fleet operation. The mathematical formulation is different from those for the classical VRP which is minimizing cost/distance/time by running vehicles in manager's point of view. The key aspect of this model is not considering the return time from the last customer to depot in every vehicle path. Thereby, the vehicle dispatcher can afford to dynamically respond to customer demand and vehicle availability. The customer's position concerned with minimizing waiting time that may be applied for the delivery of product required freshness or delivery time. Extensive experiments are carried out to compare the performance of minimizing delivery completion time by using the ILOG Solver which has the advantage of solving quickly an interim solution very near an optimal solution. The experimental results show that the suggested model can easily find near optimal solution in a reasonable computational time under the various combination of customers and vehicles.

• Journal of Distribution Science
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• v.13 no.5
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• pp.83-90
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• 2015

Purpose - This research aims to understand the different behaviors of consumers according to cognitive age. Specifically, this research is focused on pro-social behavior. Pro-social behavior is defined as behavior benefiting others, rather than behavior benefiting one's self. It often entails individual risk or cost, such as when giving resources to others, waiting in line, asking for or paying a fair price, or risking one's life in battle. Therefore, we sought to understand consumer psychology and cognitive age as a reflection of inner psychology. People frequently perceive themselves as younger or older than their chronological ages. This self-perceived or cognitive age is a subjective age perception independent of actual chronological age. The discrepancy degree between chronological and cognitive age represents how much individuals perceive themselves as younger than they are. This study examines the gap in donation intention based on cognitive age. In order to investigate cognitive age, composed of four sub-categories (feel-age, look-age, do-age, and interest-age), this study explores the differential donation intention based on cognitive age, which determines the relationship between the young age and old age. Research design, data, and methodology - Data research was conducted by gathering 216 survey samples, excluding those with unreliable answers. Data coding and cleaning were used and SPSS 19.0 software for the data analysis. The respondents were categorized into two types, younger cognitive ages and older cognitive ages. Additionally, we analyzed the moderating variables. In particular, we used cognitive age degree and congruency level (cognitive age low vs. cognitive age high) × (congruency close vs. congruency distant) between - subjects design. First, regression was done to verify the difference between chronological age and cognitive age. Second, a t-test was done to verify the difference of cognitive age level in donations. Third, ANOVA (analysis of variance) was done to verify the difference between cognitive age and congruency in donations. Last, ANOVA was done to verify the difference between cognitive age and moral judgments in donations. Result - The results show most respondents perceive themselves as younger than their chronological ages. In particular, older respondents feel they are younger than their actual age. Moreover, the result of the comparison between low degree and high degree groups of cognitive age, show high donations at the higher degree of cognitive age groups. In addition, the closer the distance to the beneficiaries, the higher the donation in high degree cognitive age groups. The higher moral judgment groups also show relatively high contributions in lower degree cognitive age groups. Conclusions - Donations belong to the category of pro-social behavior reflecting an individual's psychological state. Therefore, it is important in understanding cognitive age. This study implies that it is necessary to take into account both cognitive age and chronological age when segmenting donors. Moreover, this study confirmed that there are different factors affecting the motives behind donations. Thus, it may be utilized to create differential donation strategies.

• Journal of KIISE:Databases
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• v.29 no.1
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• pp.34-43
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• 2002

Since traditional static metadata set like Dublin Core has static metadata attributes about bibliography information, integration of metadata for various metadata, problems about standard and extension of metadata must be considered for applying it to new environment. Specially, as event-driven metadata write method included the notion of e-commerce come out for interoperability in digital libraries, traditional metadata management which cannot distinguish between different kinds of update operations to new extension of metadata set occurs unsuitable waiting of update operation. So, improvement is needed about it. In this paper, we show whether alleviative transaction consistency can be applied to digital library or not. Also it would divide newer metadata into static metadata attribute connected in read operation within user read-only transaction and dynamic metadata attribute in update operation within dynamic(e-commerce) update transactions. We propose newer metadata management algorithm considered in classfication of metadata attributes and dynamic update transaction. Using two version for minimal maintenance cost and ARU(Appended Refresh Unit) for dynamic update transaction, to minimize conflict between read and write operations shows fast response time and high recency ratio. As a result of the performance evaluation, we show our algorithm is proved to be better than other algorithms in newer metadata environments.