• Korean Journal of Construction Engineering and Management
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• v.9 no.6
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• pp.204-215
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• 2008

Demolition work is a precedence activity that is performed earlier than other remodeling activities. And demolition work is one of the critical path activities. So, demolition work is needed for systematic plan and management. However, contractors of the remodeling project established a rough plan and did not consider recycling wastes, safety of workers and structural stable of building. To improve this problem, a eco-friend process model of remodeling project is needed to be established. The process model is composed of five phases; 1) survey and analysis of general condition of demolition work, 2) prepare documents of demolition work 3) establishing demolition work plan, 4) demolition and inspection, 5) post-demolition management. Especially, demolition documents are based on establishing WBS, selecting the equipment and method, waste management and structure reinforcement. A process model of eco-friend demolition work is developed by using IDEF0 method.

• Journal of Educational Research in Mathematics
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• v.22 no.4
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• pp.557-580
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• 2012

Common Core State Standards for Mathematics(CCSSM) is a blueprint for school mathematics in 2010s of the United States. CCSSM can be divided into two major parts, the standards for mathematical content and the standards for mathematical practice. This study focused on the latter. Mathematical practice comes from the mathematical process in 'Principles and standards for school mathematics(NCTM, 2000)' as well as the mathematical proficiency in 'Adding it up(NRC, 2001)'. It is composed of eight standards which mathematically proficient students are expected to do. From Korean perspective, it can also be comparable with the mathematical process which contains mathematical problem solving, mathematical reasoning, and mathematical communication and was provided by the 2009 revised national curriculum for mathematics in Korea. However, few focused the standards for mathematical practice among the studies related to CCSSM in Korea. Moreover, there is a study that even ignores the existence of the standards for mathematical practice itself. This study aims to understand the standards for mathematical practice through analysing the document of CCSSM and its successive materials for implementing the CCSSM. This understanding will help effective implementation of the mathematical process in Korea.

• Journal of the Korea Concrete Institute
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• v.15 no.2
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• pp.246-253
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• 2003

Although concrete members are not normally designed to resist direct tension, the knowledge of tensile strength is of value in estimating the cracking load. In general, there are three types of test method for tensile strength ; direct tension test, flexural tension test, and splitting tension test. Though direct tensile strength represents the real tensile strength of concrete, direct tension tests are seldom carried out, mainly because it is very difficult to applicate a pure tension force. The purpose of this paper is to investigate the test methods, effect of aspect ratio, and the size effect on the direct tensile strength. Direct tension test, using bonded end plates, follows RILEM and U.S.Bureau of Reclamation. And other test methods follow ASTM provisions. Four kinds of aspect ratio and two kinds of size effect are tested. Same variables are tested by direct tension test and splitting tension test for comparison between the two test methods. Test results show that direct tensile strength of concrete is more affected by aspect ratio and size than other kinds of strength.

• The Journal of the Korean dental association
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• v.45 no.12 s.463
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• pp.753-760
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• 2007

Recently orthodontics in elderly people is continually increasing due to aging of the society arising from decrease of birth rate as well as death rate. As the elderly population grows, needs for oral health care increases, and elderly patients with poor teeth alignment need more attention with orthodontic treatment. Our study analyzes various treatment protocols for different cases of aged orthodontic patients, and following are considerations in orthodontic treatment of elderly patients. 1. Periodontal treatment should be preceded before orthodontic treatment. 2. Periodontal condition should be considered when selecting teeth for extraction 3. In dealing with the residual prosthesis, condition of prosthesis, anchorage availability, and need for size reduction, patient seconomic status should be taken into consideration. 4. Fixed retainers are recommended for retention.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.85-92
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• 2008

Demolition work is a precedence activity that is performed earlier than other remodeling activities. And demolition work is one of the critical path activities. So, demolition work is needed for systematic plan and management. However, contractors of the remodeling project established a rough plan and did not consider recycling wastes, safety of workers and structural stable of building. To improve this problem, a eco-friend process model of remodeling project is needed to be established. The process model is composed of five phases; 1) survey and analysis of general condition of demolition work, 2) prepare documents of demolition work 3) establishing demolition work plan, 4) demolition and inspection, 5) post-demolition management. Especially, demolition documents are based on establishing WBS, selecting the equipment and method, waste management and structure reinforcement. A process model of eco-friend demolition work is developed by using IDEF0 method.

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.2
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• pp.45-53
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• 2013

In this study, steel-pier's structural behavior by design variables of ribs were analyzed in order to improve structural details of ribs supporting double base plates. A numerical analysis was conducted using commercial FE analysis program. Anchor bolts and reinforced bars were made of BEAM element, and coefficient of friction was applied to contact surfaces. After that, the analytical result was compared with experiment of previous study to verify analysis methods. Steel-pier's load-displacement relation was analyzed according to various rib's design variables (rib's central angle, height, thickness) by using proven analysis methods, and proper rib's design ranges were proposed.

• Journal of the Society of Naval Architects of Korea
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• v.35 no.1
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• pp.88-97
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• 1998

Large aluminium extrusions can be used in rolling stocks and high speed vessels to reduce weight and labor cost. As sandwich plates with corrugated core have enough strength in transverse and longitudinal direction, welding lines to connect members are reduced and transverse members to strength longitudinal members are not required. However, for proper design of aluminium extrusion plates, understanding of structural behaviors of the exclusions are necessary. In this paper, at first, detailed finite element analysis is carried out to understand structural behavior. And then, simple theoretical formulas for design purpose are proposed using the orthotropic plate theory. Shear stresses resulting from end twisting which is characteristics of deep aluminium extrusion plates can also be calculated by the simple theoretical formula. Comparison with the results by detailed finite element analysis shows good accuracy of the proposed simple formulas. The simple formulas can be useful in repetitive analysis in the initial design stage.

• Culinary science and hospitality research
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• v.19 no.5
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• pp.170-183
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• 2013

The purpose of this study is to classify the attributes of culinary educational quality by using the Kano model. This study carried out literary research and empirical analysis. Data were collected among 486 students whose major is culinary arts and analyzed with SPSS 19.0 and EXCEL 2007. It classified culinary educational quality by employing the Kano model and modified the Better and Worse quotients suggested by Timko. The results of the study are as follows. First, it was found that total 25 attributes could be classified into 17 Attractive quality attributes, 2 Must-be quality attributes and 6 Indifferent quality attributes, while One-dimensional quality, Reverse quality and Questionable quality attributes were not found. Second, according to the Better and Worse quotient by Timko, "Objective instructor's evaluation" item was the highest score in the Better quotient. On the other hand, the "Having foreign professors" item is the lowest in the Worse quotient. Third, marketing implications and limitations were discussed.

• Journal of the Korean Geotechnical Society
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• v.19 no.2
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• pp.279-289
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• 2003

Geosynthetic reinforced earth wall was introduced about 20 years ago and many structures have been constructed. Especially, segmental concrete panel facing and friction tie system are the most popular system in Korea, and this friction tie was composed of high tenacity PET filament and LDPE(Low Density Polyethylene) sheath. Due to the lack of direct-test results, design coefficients of friction tie (creep reduction factor) had been determined by quoting the previous and the foreign reference data. This is an unreasonable fact for the use of friction ties. In this study, the creep tests were performed to evaluate the creep behavior of friction tie, and the reduction factor of creep was calculated for the correct design of geosynthetic reinforced earth retaining walls. From the test results, finally it was found that the allowable creep strength of friction tie is 60% of Tult during service life, and creep reduction factor is 1.67 for each grade of friction ties.

• Tunnel and Underground Space
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• v.8 no.4
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• pp.321-331
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• 1998

A reliable analysis of tunnelling is needed to accomplish technically sound design and safe and economical construction. For the reliable analysis, a series of procedures of construction which include excavation and support stages must be considered. In this study, rock-support response behavior is studied and simulated in 2-D and 3-D finite element methods. Through the analysis of rock-support response behavior, the effects of the properties of shotcrete on the load distribution ratio can be quantified. The load distribution ratios for different rock types, different unsupported spans and various lateral earth pressure coefficients can be determined from the results of the 3-D finite element analysis. This load distribution ratios can be applied to a practical tunnel design through understanding of the trend of those various factors affecting the rock-support interaction.