• Journal of The Korean Association of Information Education
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• v.11 no.1
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• pp.21-28
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• 2007

Along with the development of telecommunication technology, educational role has been considerably changed and NEIS is introduced and operated for the digital educational administration. However, the function of NEIS is so limited when operated in each school. As a result, Korean government prepares the plan to install and operate a new School Affairs System by separating 3 areas from 27 areas of NEIS. School Affairs System has been used in schools since March, 2006. In this regard, this study attempts to analyze the current status and tasks of using the system in elementary schools. The result of the study shows that about 67% teachers use the system once or twice a day. Most of teachers answer that they get help from other teachers if they have any problem in operating the system. Many teachers affirmatively answer to the design and function of the system, and they are satisfied with the convenience and efficiency of the system. However, they feel difficulty to be familiar with the system sue to the frequent change. The importance of electronic certificate and personal information is well recognized and managed in terms of the security of the system. Facilities need to be well equipped, and information exchange system need to be developed to accept each school's request to improve the function of the system. In addition, applicable laws need to be arranged, clear guideline of educational administration agency and principal's strong intention are required to relieve teachers' work load.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.5 s.347
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• pp.84-93
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• 2006

Ethernet-PON is an emerging access network technology that provides a low-cost method of deploying optical access lines between OLT and ONUs. It has a point-to-multipoint and multipoint-to-point architecture in downstream and upstream direction, respectively. Therefore, downstream packets are broadcast from an OLT toward all ONUs sithout collision. On the other hand, since alt ONUs share a common channel, the collision may be occurred for the upstream transmission. Therefore, earlier efforts on Ethernet-PON have been concentrated on an upstream MAC protocol to avoid collision. But it is needed to control downstream traffic in practical access network, where the network provider limits available bandwidth according to the number of users. In this paper, we propose a traffic control scheme for supporting the fairness of the downstream bandwidth. The objective of this algorithm is to guarantee the fairness of ONUs while maintaining good performance. In order to do this, we define the service probability that considers the past traffic information for downstream, the number of tokens and the relative size of negotiated bandwidth. We develop the simulation model for Ethernet-PON to evaluate the rate-limiting algorithm by using AWESIM. Some results are evaluated and analyzed in terms of defined fairness factor, delay and dropping rate under various scenario.

• The Journal of Society for e-Business Studies
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• v.20 no.1
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• pp.183-199
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• 2015

Due to the Four Major Rivers Restoration Project, Nakdong River Estuary Barrage's designed flood quantity has been largely increased, and this has caused to construct several drainage gates at the right side of Eulsukdo island to secure the safety of downstream river area. For successful functioning of Nakdong River Estuary Barrage, such as flood control, disaster prevention, and the securing of sufficient water capacity, drainage gates at the both sides of island have to operate systematically and reliably. To manage this under restricted personnel and resources, we have implemented the IOS (Integrated Operation System) by integrating previous facilities and resources via information and communication technologies. The IOS has been designed to have higher availability and fault tolerance to function continuously even with the partial system's failure under the emergency situation like flood. Operators can use the system easily and acknowledge alarms of facilities through its IWS (Integrated Warning System) earlier. Preparing for Integrated Water Resources Management and Smart Water Grid, the architecture of IOS conformed to open system standards which will be helpful to link with the other systems easily.

• Journal of Nutrition and Health
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• v.53 no.3
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• pp.255-270
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• 2020

Purpose: The purpose of this study was to identify the factors that influence the consumption of convenience foods among Korean adolescents. Methods: This study had a descriptive cross-sectional study. Data were obtained from the 15th (2019) Korea Youth Risk Behavior Web-based Survey, which involved a nationwide representative sample of 57,303 middle- and high-school students. Convenience-food consumption was defined by frequency of adolescents consuming convenience foods obtained from convenience stores, supermarkets, and cafeterias over the previous 7 days. The analyzed variables were related to sociodemographic, mental health, and health behavior. The Rao-Scott χ² test was applied to examine the difference in the rate of consuming convenience foods obtained from convenience stores according to each factor. Hierarchical logistic regression was conducted to examine the factors that influence convenience-food consumption among Korean adolescents. Results: It was found that 29.1% of Korean adolescents consumed convenience foods obtained from convenience store more than three times per week. The significant influencing factors were female sex; low subjective academic achievement, and subjective household economic status; high perceived stress; low subjective sleep sufficiency; experience of depression; suicidal ideation; lower physical activity; skipping breakfast; lower consumptions of fruit, milk, and vegetables; higher consumptions of soda drinks, sweet drinks, caffeine, and fast food; lower water intake; current smoking and drinking; drug use; and experience of violence. Conclusion: These findings provide a better understanding of the sociodemographic, mental-health, and health-behavior factors that influence the consumption of convenience foods among Korean adolescents. We suggest that differentiated policies, strategies, and nutrition education need to be developed and implemented, in order to address the above-mentioned factors and thereby reduce such behaviors among Korean adolescents.

• Journal of the Korea Institute of Building Construction
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• v.18 no.2
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• pp.151-159
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• 2018

Accident rate in the construction industry of South Korea is increasing every year, and it represents the highest percentage among industries. This shows that activities performed to prevent safety accidents in the country are not efficient when it comes to reduce the accident rate. In order to resolve this issue, a model for the prediction of human accidents should be established. In addition, it is required a quantification study based on pattern of human accidents. Therefore, the objective of this study is to quantify uncertainty of human accidents risk and predict how to change in various circumstances by using Monte Carlo Simulation. To achieve the objective, first, pattern of human accidents was defined. Second, insurance claim payout and information of human accidents during 14 years in construction site were collected. Third, descriptive analysis is conducted to determine the characteristics of the accident pattern. Fourth, to quantitatively analyze the pattern of the human accidents, the population of each accident occurrence and payout were estimated. Finally, estimated populations was analyzed according to characteristics of distribution by using Monte carlo simulation. In the future, this study can be used as a reference for developing the safety management checklist in construction site and development of prediction models of human accident.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.820-828
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• 2015

This study was carried out to determine the effects of vernalization, temperature, and soil water deficit (SD) on mesophyll cells, growth, and yield of Chinese cabbage (Brassica campestris L). The palisade parenchyma and spongy tissues of Chinese cabbage were observed under full irrigation and two weeks of SD treatment. These cells were severely collapsed by four weeks SD treatment. The SD treatment had the greatest influence on the growth of Chinese cabbage among the tested treatment factors (vernalization, temperature, and SD), growth significantly decreased by severe drought treatment (four weeks SD treatment). In addition, the relative growth rate, unit leaf rate, leaf area ratio, specific leaf area, and leaf weight ratio were significantly affected by SD treatment; however, other individual factors and their combined treatments did not influence the analyzed growth parameters. The yield under vernalization after high temperature and full irrigation treatments was 3,056 kg/10 a, which was the greatest among all the tested treatments, while four-week SD treatment significantly reduced the yield. Head formation of Chinese cabbage was not altered under SD treatment, and vernalization treatments did not induce bolting. Our results indicated that collapsing mesophyll cells and reduced growth and yield were induced by SD treatment. Thus we suggest that optimal irrigation system should be install to avoid or overcome crippling drought conditions in the open field.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.12
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• pp.2511-2519
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• 2015

In maritime logistics, the technology for transmitting status information has been greatly developed, but it has not been available in general logistics environment or it is impossible to support two-way communication as it simply receives and transfers a container's information. In particular, to support two-way communication in all sections of the global maritime logistics, the address value, which can identify the tag, should be managed. In this context, to improve the 433 MHz-based RFID, the project called "DASH 7" has been conducted in recent years. However, it has stopped proceeding because of its slow progress, including the standardization and development of references. In this paper, we introduced an active IP-RFID system configuration for real-time communication in global maritime logistics using a two-way communication-which is characteristic of an IP-applying virtual address values in the RFID tag, and proposing its process and function. When you apply the IP-RFID system proposed in this paper, not only real-time status tracking in the maritime logistics area is possible, but it is also applicable for controlling the tag.

• Journal of the Korea Concrete Institute
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• v.18 no.1 s.91
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• pp.57-64
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• 2006

The crack presented in concrete structures causes a structural defect, the durability decrease, and external damages etc. Therefore, it is necessary to improve durability through the effort to control the crack. Fluosilicic acid($H_2SiF_6$) is recovered as aqueous solution which absorbs $SiF_4$ produced from the manufacturing of industrial-graded $H_3PO_4$ or HF. Generally, fluosilicates prepared by the reaction between $H_2SiF_6$ and metal salts. Addition of fluosilicates to cement endows odd properties through unique chemical reaction with the fresh and hardened cement. Mix proportions for experiment were modulated at 0.45 of water to cement ratio and $0.0{\sim}2.0%$ of adding ratio of fluosilicate salt based inorganic compound. To evaluate correlation of concrete strength and adding ratio of fluosilicate salt based inorganic compound, the tests were performed about design strength(21, 24, 27 MPa) with 0.5% of adding ratio of fluosilicate salt based inorganic compound. Applications of fluosilicate salt based inorganic compound to reduce cracks resulted from plastic and drying shrinkage, to improve durability are presented in this paper. Durability was evaluated as neutralization, chloride ion penetration depth, freezing thawing resistant tests and weight loss according reinforcement corrosion. It is ascertained that the concrete added fluosilicate salt based inorganic compound showed m ability to reduce the total area and maximum crack width significantly as compared non-added concrete. In addition, the durability of concrete improved because of resistance to crack and watertightness by packing role of fluosilicate salt based inorganic compound obtained and pozzolanic reaction of soluble $SiO_2$ than non-added concrete.

• The KIPS Transactions:PartD
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• v.17D no.4
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• pp.259-270
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• 2010

Information systems nowadays are heterogeneous and distributed which integrate the enterprise information by processes. They are also very complex, because they are linked together by processes. It aims to integrate the systems so that these systems work as one system. A process is a framework which contains all of the business activities in an enterprise, and has a lot of information which is needed for measuring performance. A process consists of activities, and an activity contains events which can be considered information sources. In most cases, it is very valuable to determine if a process is meaningful, but it is difficult because of the complexity in measuring performance, and also because finding relationships between business factors and events is not a simple problem. So it would reduce operation cost and allow efficient process execution if I could evaluate the process before it ends. In this paper we propose an event based process measurement model. First, we propose the concept of process performance measurement, and a model for selecting process and activity indexes from the events which are collected from information systems. Second, we propose at methodologies and data schema that can store and manage the selected process indexes, the mapping methods between indexes and events. Finally, we propose a process Performance measurement model using the collected events which gives users a valuable managerial information.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.24 no.2
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• pp.269-288
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• 2013

The development of IT (information technology) has brought about many types of new services, and the traditional sectors such as libraries and information management fields have actively applied new technology to improve the quality of their services. Many of these newly developed services are described under the term 'Web 2.0', in the sense they are next-generation forms of services, and this coinage is duplicated in the term 'Library 2.0', specifically referring to the library services equipped with Web 2.0 technology. Active acceptance of advanced IT to library services is very important to enhance the value and role of library in this rapidly changing information environment. So far, libraries in Korea and abroad have already been putting a lot of efforts and resources to develop and provide technically advanced services. Despite these efforts, it is found that some of these new services have failed to attract users' attention and interest, resulting in the low rates of usage. This study, therefore, reviews current state of the "Folksonomy" based services provided in Korean college libraries as a type of Library 2.0 services, and assess their usage rates. The result of this evaluation is then used to develop a guideline to improve and mobilize the use of such services.