• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.3
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• pp.363-368
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• 2001

It is well known that numerous factors influence the light output of curing units, but many dentists are un aware that the output of their curing lights are inadequate. This study was conducted to evaluate the light in tensity of visible-light curing units in some private dental clinics and hospital dental clinics. In order to determine the maximum light intensity of the curing units, lamps, filters and fiber optic bundles, they were replaced with new ones and light intensity was remeasured. Light intensity was measured by employing a digital radiometer (EFOS model #8000, USA). Light intensity ranged in $29\sim866mW/cm^2$ (below $150mW/cm^2$ ; 17.8%, $150\sim300mW/cm^2$ : 46.6%, above $300mW/cm^2$ ; 35.6%). The replacement of the components increased the light intensity, with maximum increases of 94.8% for lamps, 82.3% for filters, 200.8% for fiber optics and 361.5% for all three parts. According to the manufacturer of radiometer, curing light is considered as unsuitable for use with a reading of above $300mW/cm^2$ by the radiometer. Applying these criteria to the present study, 64.4% of the curing units required repair or replacement. The results of this study indicated that the light intensities of the curing units used in dental practice were lower than optimum level.

• Journal of Korean Society of Forest Science
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• v.96 no.3
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• pp.235-244
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• 2007

Potentials of AR CDM project in North Korea are assessed and feasible land area for AR CDM project is estimated. According to our estimation, There could be 515,000 hectares of forest lands deforested before 1990 in North Korea and 8,854 hectares at the regional level of Gae-sung City, which are eligible for AR CDM project, based on researches of satellite image analyses conducted from 1980's to 1990's. A baseline scenario assumed 44.73 tones of carbon stored in soil per hectare with no vegetation above ground remained during the project period following the default value of IPCC's Good Practice Guidance for LULUCF considering soil structure, climate and land use of the project area. The scenario also assumes that black rocust (Robinia pseudoacacia) is planted and the CDM project is implemented for 20 years. The costs for producing greenhouse gases CER (certified emission reduction) credits include costs of tree planting and forest management, and costs of project negotiation and transactions for issuing the credits. It is estimated that 376 tones of carbon dioxide per hectare can be accumulated and 503 temporary CER credits per hectare and 265 long-term CER credits per hectare could be produced during the project period. It is estimated to cost US$ 4.04 and US$ 7.67 to provide one unit of temporary credit and long-term credit, respectively. These values can be regarded as the cost of conferring emission commitment of a country or a private entity. However, it is not clear which option is better economically because the replacement periods are different in these two cases.

• Journal of Korean Society of Rural Planning
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• v.13 no.1 s.34
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• pp.85-95
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• 2007

Hot springs development will be more activated with the five-day work week system than before. Nevertheless, investment and development achievement of hot springs has not resulted in a successful performance to foster townships, and this calls upon locals to build a guideline to develop hot springs. This study intends to analyze laws on hot springs, which influence mostly on the hot spring development, to gather up the information on the present state of the development, and to suggest considerations for further development plans. Features of the hot spring development are as follows: One is that metropolitan cities will discover hot spring resources more than small cities. Therefore the development will be twofold : one for resort tour and the other for one-day rest and recreation. In addition, Korean laws on hot springs are more site development-oriented to support tourism and recreation than to protect environment and discover unused resources. This makes hot spring development easier and efficient being supported by hot spring law, law on territory development and use, and tourism promotion law. On the other side, planned landscape trimming can be uniformized and unharmonized in terms of local identity and environment-friendliness. This is why careful considerations such as goods and bads of the local resources, local history and culture are needed in hot spring development. A long-term development project should include remodeling based on local identity and development trends. The third point indicates that Korean hot springs development has recorded relatively low performance due to difficult private capital attraction, and a high fence on land purchase and development approval. It is essential to release restrictions on the hot spring development-especially on those whose development performance has not been successful so that best practice can be supported by the government in remodeling and marketing. New plans on hot spring development should be also examined based on developer's capacity and local authorities' volition on the plan. Last point shows that most hot springs development plans have been designed only based on territory utilizing plan and facilities arrangement, not considering much on fund-raising, operational plan or feasibility analysis. Therefore the tourism promotion law should reinforce guidelines on tourist site approval system by supplementing criteria. At the same time, an education on tourism development planning is necessary to deepen developers' understanding, since most developers are experts more on city development, landscape architecture, designing, constructing and engineering than tourism development.

• Korean Journal of Community Nutrition
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• v.23 no.4
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• pp.352-365
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• 2018

Objectives: The Korean Food Composition Table (KFCT) was first published in 1970, and has since been updated every five years by the Rural Development Administration (RDA). This study was conducted to introduce the development strategies, features, and challenges of the $9^{th}$ revision of the KFCT. Methods: Due to the increasing demands of nutrient database users and generators, the RDA started a new research project in 2013 to improve the quantity and quality of data for the $9^{th}$ revision of the KFCT. Over 1,000 food items frequently consumed in Korea were selected as key foods using the results of the Korean National Health and Nutrition Examination Survey. About 200 raw materials and processed food items were collected and analyzed every year. Target nutrients that were analyzed by collaborative labs, such as, sugars, selenium, iodine, and biotin, were increased from 22 to 43. Analytical sample handling procedures and data quality evaluation systems were also established in collaboration with 10 contracted labs. Data were evaluated for data quality according to the FAO/INFOODS, CODEX, and AOAC guidelines. Results: The $9^{th}$ revision contains data on 3,000 food items and up to 43 and 140 food nutrients for the printed table and the excel database file, respectively. Overall, 1,485 data items were newly added, 973 of which were provided by the RDA and 512 were cited from foreign nutrient databases. The remaining 1,515 food items were maintained as in the $8^{th}$ revision. Conclusions: The KFCT provides the basic infrastructure for food and nutrition policy, research, and dietary practice in South Korea. The use of the KFCT has increased exponentially in the past few years in both public and private sectors; accordingly, increased efforts should be paid to the preparation, improvement, and maintenance of KFCT.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.2
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• pp.122-126
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• 2011

Introduction: In the lateral window approach for a maxillary sinus bone graft, there has been considerable controversy regarding the placement of a barrier membrane over the osteotomy site. In particular, when there is no damage to the Schneiderian membrane, clinicians should decide whether to use a barrier membrane or not, considering the benefits and costs. This study presents the clinical cases to demonstrate that only repositioning the detached window can lead to satisfactory bony healing of the grafted material without using a barrier membrane in the lateral approach for a maxillary sinus bone graft. Materials and Methods: Five consecutive patients were treated with the same surgical procedures. After performing the antrostomy on the lateral maxillary wall using a round carbide bur and diamond bur, the bony window was detached by a gentle levering action. After confirming no perforation of the Schneiderian membrane, the grafting procedure was carried out the detached window of the lateral maxillary wall was repositioned over the grafted material without using a barrier membrane. A gross examination was carried out at the postoperative 6 month re-entry, and the the preoperative and postoperative dental computed tomography (CT) at re-entry were compared. Results: All the procedures in the 5 patients went on to uneventful healing with no complications associated with the bone graft. Satisfactory bone regeneration without the interference of fibrous tissue on the gap between the repositioned window and lateral wall of the maxillary sinus was observed in the postoperative 6 month re-entry. The CT findings at re-entry revealed the, reconstruction of the external cortical plate including repositioned bony window. In addition, the loss of the discontinuity of the lateral maxillary wall was confirmed. Conclusion: This preliminary report showed that the detached window, which was just repositioned on the grafted material, could function as a barrier membrane in the lateral approach for a maxillary sinus bone graft. Therefore additional morphometric and histologic studies will be needed.

• Communications of Mathematical Education
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• v.34 no.3
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• pp.299-324
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• 2020

The purpose of this study was to identify high school students' mathematics learning style and its characteristics according to their personality disposition types and to propose mathematics learning strategies fit into each personality disposition type. For this purpose, MBTI personality test and survey to find mathematics learning style for 375 high school students were executed. The results were as follows. First, many students highly evaluated the effects of private education and prefer reference book to textbook. Second, there were significant differences on following variable domains of mathematics learning style such as learning attitude, learning habit(concentrativeness to concept understanding), problem solving strategies(effort for problem comprehension, use of various strategies), self management(metacognition) by MBTI personality disposition types(SJ, SP, NT, NF groups). Third, based on the results, the following mathematics learning strategies fit into each personality disposition type were recommended. SJ type students are needed to effort creative approach for open problem and to use mindmap as mathematics learning strategy. SP type students are needed to fulfill stepwise problem solving process and to effort constantly practice long/short term learning objectives. NT type students are needed to expand opportunity to study with friends and to use SRN(self reflection note) or mathematics journal writings as mathematics learning strategy. NF type students are needed to use mathematics learning note writing activity which include logical basis for each step of problem solving and to invest more time on learning algebra which need meticulous calculation.

• Journal of Korean Society of Transportation
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• v.35 no.3
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• pp.220-233
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• 2017

Traffic volumes are fundamental data widely used in various traffic analysis, such as origin-and-destination establishment, total traveled kilometer distance calculation, congestion evaluation, and so on. The low number of links collecting the traffic-volume data in a large urban highway network has weakened the quality of the analyses in practice. This study proposes a method to estimate the traffic volume data on a highway link where no collection device is available by introducing a spatial statistic technique with (1) the traffic-volume data from TOPIS, and National Transport Information Center in the Ministry of Land, Infrastructure, and (2) the navigation data from private navigation. Two different component models were prepared for the interrupted and the uninterrupted flows respectively, due to their different traffic-flow characteristics: the piecewise constant function and the regression kriging. The comparison of the traffic volumes estimated by the proposed method against the ones counted in the field showed that the level of error includes 6.26% in MAPE and 5,410 in RMSE, and thus the prediction error is 20.3% in MAPE.

• Journal of the Korean Society for Library and Information Science
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• v.52 no.2
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• pp.27-47
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• 2018

The purpose of this study is to find a better way for placement of teacher librarians. So, the literature research is applied for the study. It is unreasonable to arrange one school librarian staff per 1,500 students, based on the criteria of the total number of personnel including that of teacher librarians and practice teachers and librarian, in accordance with the existing enforcement decree of Article 7. In fact, this clause, linked to other related regulations, makes it difficult to place teacher librarians. And the quota of teacher librarians is noticeably low as compared with that of other teachers who are not-teaching the subject matter. This operates disadvantageously to teacher librarians when it comes to assigning quota in secondary teacher selection test and the accumulation of this phenomenon gradually worsens the current situation. The roles of teacher librarians and librarians should be defined separately when amending the Enforcement Decree of School Libraries Promotion. And we should also take into consideration that the number of students per school is around 500. Therefore, Enforcement Decree of School Libraries Promotion Act should be revised toward placing teacher librarians depending on the size and number of schools. Predictability should be secured in teacher librarians selection test. In addition, flexibility should be granted to the training institute so that many people can prepare the teacher librarians qualification. Finally, it is necessary to increase the teacher librarian capacity for private schools. This study will be the basis of the theoretical foundation for stable teacher librarian placement.

• Journal of Science and Technology Studies
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• v.4 no.2 s.8
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• pp.103-127
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• 2004

This paper analyzes the strategic planning process of NASA (National Aeronautics and Space Administration) including its center, GSFC (Goddard Space Flight Center) in the framework of strategic planning in publicly funded R&D organizations. To construct this framework, theories have been considered mainly focused on strategic management and planning, its application on public sector, and characteristics of R&D activities. As a result, the framework could be set up in accordance with the process of strategic planning. Also, as a case study, we explored the practice of strategic planning process and organizational implementation of NASA and GSFC. During the analysis on the strategic process of NASA and GSFC, we could draw some lessons out as follows: First, we should consider the differences between private and public sectors when we establish strategic planning in public sector. Second, the stakeholder analysis should be involved in setting the mission, goals, and strategies of an organization. Third, it is necessary to identify and assess the socio-economic effects or public benefits by R&D programs of the organization and use the feedback on its goal. Fourth, to implement strategic planning effectively, planning process should be closely integrated with the management process such as setting goals, securing budgets, and evaluating the organization. Conclusively, the analysis on NASA and GSFC contribute to implementing strategic planning in publicly funded R&D organizations by providing the appropriately modified framework. As an extension of this study, more deliberate analysis on various practices of strategic planning and performance indicators should be followed.

• Journal of Korean Philosophical Society
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• v.126
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• pp.213-233
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• 2013

The aim of this paper is to reveal the ethical problem of insider trading. 'Insider trading' refer to obtaining information from non-public sources such as private acquaintances about trade secret, using it purposes of enhancing insider's financial advantages. And sometimes such a practice can be conducted fraudulently. Therefore, the focus of this paper will be on fairness or justice arguments against insider trading. And all kinds of discussion this paper are to focus the underlying consideration behind these arguments, that is, the underlying consideration about violation of ethical standards of fairness. First, one of these arguments argues that insider trading does necessarily involve defrauding general investors such as general employees, general stockholders. And economic power and unjust advantage of insider can be exercised to the detriment of this non-insider's interests. Second, another argument argues that insider trading undermines competition which is the principle of any free market. And insider trading is not only a complication in the free market mechanism, but also thwarts free competition which free markets depend. Third, the final argument argues that insider trading will be made something unfair about the concept of equal access to information. This argument argues, therefore, that to permit insider trading would be to set up stock market trading rules that are unfair to non-insiders.