• Journal of Korean Society of Forest Science
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• v.100 no.3
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• pp.455-465
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• 2011

In order to assess and mitigate climate change, the role of forest biomass as carbon sink has to be understood spatially and quantitatively. Since existing forest statistics can not provide spatial information about forest resources, it is needed to predict spatial distribution of forest biomass under an alternative scheme. This study focuses on developing an upscaling method that expands forest variables from plot to landscape scale to estimate spatially explicit aboveground biomass(AGB). For this, forest stand variables were extracted from National Forest Inventory(NFI) data and used to develop AGB regression models by tree species. Dominant/codominant height and crown density were used as explanatory variables of AGB regression models. Spatial distribution of AGB could be estimated using AGB models, forest type map and the stand height map that was developed by forest type map and height regression models. Finally, it was estimated that total amount of forest AGB in Danyang was 6,606,324 ton. This estimate was within standard error of AGB statistics calculated by sample-based estimator, which was 6,518,178 ton. This AGB upscaling method can provide the means that can easily estimate biomass in large area. But because forest type map used as base map was produced using categorical data, this method has limits to improve a precision of AGB map.

• The Journal of Korean Philosophical History
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• no.39
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• pp.115-142
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• 2013

The purpose of this study was to explore the changes of values in Korea focused on the period from liberation in 1945 to industrialization in the late 1970s. Those periods classified into 'Transitional Era' and 'Industrial Era' based on historical events significantly influenced the changes of value system of Korean people or Korean society. In this study, not only main values and right people for society but also the way of changing value system in those periods were suggested by investigating factors of politics, economy and society. The results are as follows : First, main values and right people for society on each period were as follows : In Transitional Era, main values were manners and social norms, and right people for this period were practical intellectuals pursuing the principle of action-oriented truth-and- knowledge-seeking. In Industrial Era, on the other hand, main values were sincerity, diligence, self-help and collaboration, and right people for this period were skilled man having occupational ability which was essential for economic development. Second, lasting value in Transitional Era and Industrial Era was patriotism. The patriotism in early Transitional Era was appealed to nation and people because of the collapse of ruling system and the absence of leaders, however, the patriotism changed to loyalty towards a national leader or seniors after the formation of new ruling system by building nation and electing a leader. On the other hand, the patriotism of Industrial Era was distinctly defined purpose for carrying out national economic policy and overwhelming Democratic People's Republic of Korea with anti-communist spirit and unification will.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.477-483
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• 2021

In a military maintenance system, the standard maintenance man-hour of weapon systems is a tool to estimate the maintenance capabilities of maintenance units, provide standards for determining the maintenance needs and workload, and provide basic data for establishing a maintenance plan. The standard maintenance man-hours of major weapon systems have already been derived and used, but the standard maintenance man-hour in a wartime maintenance environment has not been computed. Therefore, the standard wartime maintenance man-hours need to be derived and This study proposes a process and method of computing the maintenance man-hours. In addition, this work suggests the criteria of collecting and screening data that is necessary for estimating the standard maintenance man-hours and introduces a methodology for analyzing the characteristics of maintenance man-hour distribution in the process. The proposed process first designs a model that reflects the wartime maintenance environment, selects statistical techniques, collects maintenance data, analyzes the descriptive statistics, estimates the distribution, and finally presents representative values of maintenance man-hour. Based on the proposed method, the standard wartime maintenance man-hours of the four weapon systems were calculated, and the distribution of the maintenance man-hours was analyzed to follow a lognormal distribution, and the method presented reliable results.

• Journal of the korean academy of Pediatric Dentistry
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• v.49 no.3
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• pp.264-273
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• 2022

Due to the development of properties of adhesive materials currently used in dentistry, the bonding ability between the brackets and the tooth enamel has been greatly improved. In general, in situations where cooperation can be obtained, adhesion of the orthodontic bracket through the conventional three-step process can show excellent bonding strength. However, if it is difficult to expect patient cooperation, as in the pediatric dentistry area, or if moisture isolation is not properly performed, the binding strength that does not reach the expected effect. As a result, various products that simplify the process for adhesion are being developed. The aim of this study was to evaluate and compare the shear bonding strength between the conventional 3-step adhesion system, self-etching primer system and one-step adhesion system that reduces the priming process. A total of 60 human maxillary, mandibular premolars were prepared. Group I (control group) were followed conventional 3-step bonding process. Group II were conditioned with self-etching primer. Group III were etched with 37% phosphoric acid and brackets were bonded with self-priming adhesive. The resultant shear bond strength of each group was measured and an adhesive remnant index (ARI) was recorded. The mean shear bond strength of group I, II, III were 14.69 MPa, 11.21 MPa and 12.21 MPa respectively. Significant differences could only be found between group I, II and group I, III (p < 0.05). The ARI indicated no significant difference among all groups.

• East European & Balkan Studies
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• v.43 no.1
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• pp.3-30
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• 2019

In order to understand the various cultural interactions caused by the wave of globalization, we need a proper lens that can observe and transmit correctly these phenomena. The result of understanding very differs depending on which lens is used. Translation can be regarded as a lens to communicate with each other in the world where language barriers exist. Literature is a kind of universal cultural heritage combined with the intellectual, artistic and social lifestyle of each society. Introducing this cultural complex, namely literature and impregnating people from other languages with the value of our Korean literature, begin with the correct translation. Translator should act as a literary missionary, not merely a simple communicator. The process of literary translation cannot be achieved by simple linguistic ability because it is a highly human scientific work that requires diverse talents from translators. The right translator for Korean literature in Romania is a person with diverse abilities and social experiences within the cultural framework of Korea and Romania. As the requirements of the translation environment from each country are different, the paradigm of foreign translation literature that Romania wants to accept may be very clear distinctively. With recognizing this characteristic environment of Romania, the value of Korean literature can be effectively spread in Romania. Translators are the creators of another original work. With this in mind, the education of Korean studies in Romania should pay more attention to the nurture of right and capable translators.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.6D
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• pp.623-629
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• 2010

Recently, the Shield TBM (Tunnel Boring Machine) construction method is used gradually to increase at the Tunnel Constructin site. However the design and application of the Shield TBM were carried out without sufficient investigation of the ground conditions in the construction site. Due to insufficient understanding to the corresponding equipment is frequently occurring unexpected construction cost and extension of a construction period. The most suitable alternative construction method was determined by analyzing tunneling rate, duration, construction cost of shield machine and tunneling data of alternative method. The result of the case study is suggested as follows. First, the accurate soil exploration on the construction site should be preceded to prevent from tunneling stoppage and schedule delay. Second, the most suitable selection of the shield machine to the ground conditions of the construction site should be executed based on the investigation. Third, the best alternative method for boring of hard rock section is 'hard rock blasting after open cut and cover method'.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5D
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• pp.655-664
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• 2008

Lean Construction recommends implementing site production management by measuring the reliability of daily production tasks, collecting the causes for failure of incomplete tasks, and identifying problems in the existing process based on the collected data. Although many research projects have been performed to introduce Lean Construction in Korea, there are not many cases in which day-to-day site production operations has been stringently evaluated based on such methods. This paper introduces three cases in which such techniques were implemented on a residential, civil infrastructure and plant project. On each project, process maps were created with the superintendents and daily production meetings were held for two weeks. Consequently, the average PPC for the three projects was 79% for PPC and 16% for PAT. In addition, the majority of the failures were due to 'Directive/Plan' and 'Prerequisites.' The results show that project stakeholders (owners, contractors, etc.) lack the ability to plan ahead and keep to their plans, and also lack the capability to synchronize workflow between themselves. The results also reveal that project participants need to be more proactive in solving process problems on site and also need to be better educated in Lean concepts and methodologies.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3B
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• pp.279-289
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• 2006

The reconstruction of low dimension nonlinear behavior from the hydrologic time series has been an active area of research in the last decade. In this study, we present the applications of a powerful state space reconstruction methodology using the method of Support Vector Machines (SVM) to the Great Salt Lake (GSL) volume. SVMs are machine learning systems that use a hypothesis space of linear functions in a Kernel induced higher dimensional feature space. SVMs are optimized by minimizing a bound on a generalized error (risk) measure, rather than just the mean square error over a training set. The utility of this SVM regression approach is demonstrated through applications to the short term forecasts of the biweekly GSL volume. The SVM based reconstruction is used to develop time series forecasts for multiple lead times ranging from the period of two weeks to several months. The reliability of the algorithm in learning and forecasting the dynamics is tested using split sample sensitivity analyses, with a particular interest in forecasting extreme states. Unlike previously reported methodologies, SVMs are able to extract the dynamics using only a few past observed data points (Support Vectors, SV) out of the training examples. Considering statistical measures, the prediction model based on SVM demonstrated encouraging and promising results in a short-term prediction. Thus, the SVM method presented in this study suggests a competitive methodology for the forecast of hydrologic time series.

• Journal of The Korean Association For Science Education
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• v.36 no.1
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• pp.177-190
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• 2016

The purpose of this study is to validate learning progressions for Earth's motion and solar system from two different perspectives of validity. One is construct validity, that is whether a hypothetical pathway derived from our study of LPs is supported by empirical evidence of children's substantive development. The other is consequential validity, which refers to the impact of LP-based adaptive instruction on children's improved learning outcomes. For this purpose, 373 fifth-grade students and 17 teachers from six elementary schools in Seoul, Kangwon province, and Gwangju participated. We designed LP-based adaptive instruction modules delving into the unit of 'Solar system and stars.' We also employed 13 ordered multiple-choice items and analyzed the transitions of children's achievement levels based on the results of pre-test and post-test. For testing construct validity, 64 % of children in the experimental group showed improvement according to the hypothetical pathways. Rasch analysis also supports this results. For testing consequential validity, the analysis of covariance between experimental and control groups revealed that the improvement of experimental group is significantly higher than the control group (F=30.819, p=0.000), and positive transitions of children's achievement level in the experimental group are more dominant than in the control group. In addition, the findings of applying Rasch model reveal that the improvement of students' ability in the experimental group is significantly higher than that of the control group (F=11.632, p=0.001).

• Journal of Oral Medicine and Pain
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• v.30 no.4
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• pp.391-400
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• 2005

Special Practitioner exists based on the need for special fields that are required to manage difficult patients with specialized skills distinguished from General practitioner. The purpose of dental specialist system is to manage patients who are not treatable by general practitioner by training doctors specializing in one specific field, thereby, enhancing health of the public. Oral Medicine deals with orofacial pain, oral soft tissue disease, forensic dentistry, oral diagnosis. In these days, living environments of city life bring about increase in stress which ultimately lead to increase in prevalence of temporomandibular disorder, oral soft tissue disease, neuropathies such as trigeminal neuralgia, and hence, the number of patients seeking help of those symptoms tend to increase. The purpose of this study was to analyze the rate of referrals and the routes of patients seeking help by investigating 3,707 patients who visited Department of Oral Medicine, College of Dentistry, Yonsei University, from August, 2004 to April, 2005. The results were as follows: 1. The types of disease referred to the Department of Oral Medicine were orofacial pain, oral soft tissue disease, forensic dentistry, oral diagnosis. 2. The rate of referrals was 58.51% which implies that more than half of the patients visiting the Department of Oral Medicine were referred. 3. The types of institution which made referrals were analyzed, and as a result, dental clinics made most of the referrals with the rate of 83.23%, while that from medical or oriental medical institutions was 16.78%. 4. Among the patients who visited the Department of Oral Medicine on their own, 30.52% gained the information about the Department of Oral Medicine from internet and mass media, and from neighbors. From the above results, most of the patients visiting the Department of Oral Medicine were found to be referred not only from the field of dentistry but also from the field of medicine. These suggest that Oral Medicine manages patients who are not treatable by general dental practitioners, and medical specialists tend to cooperate with the Department of Oral Medicine to manage diseases associated with Oral Medicine. Therefore, the role of Oral Medicine can be considered to be important as a special field, and the results of this study should be considered when working out a policy of Dental specialist system on demand and supply of residents in the future.