• 가족자원경영과 정책
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• 제4권1호
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• pp.113-128
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• 2000

The purpose of this study is to investigate the actual condition of Coming-of-Age Ceremonies and to suggest the building blocks of a modern program for Coming-of-Age Ceremonies. This will be done through the study of the consciousness of students who participated in such ceremonies. This study was compiled from 262 data sources. The major findings as follows: 1. On evaluation of the opinions of student that have participated in Coming-of-Age ceremonies, a conclusion was drawn that such ceremonies were suitable held at age twenty. Also, drawn from the study was that most students preferred a event interweaving traditional ceremonies with blessing ceremonies and viewed that the current vogue of presenting expensive gifts was not suitable. Pertaining to the type of gifts preferred, school supplies and inexpensive accessories were on top of the list. In addition, a great majority agreed that traditional Coming-of-Age Ceremonies were difficult to perform but interesting and instructive. 2. It was discovered that a substantial majority perceived the need of Coming-of-Age Ceremonies and drew satisfaction from such events. The study also showed that satisfaction in school life and activeness in extracurricular functions was directly proportional to the student’s recognition of the need for the student’satisfaction drawn from Coming-of-Age Ceremonies. 3. It was shown that positive correlations existed between the need for and satisfaction drawn from Coming-of-Age Ceremonies and recognized the need for the comparison of modern and traditional Coming-of-Age Ceremonies and the establishment a desirable concourse of such ceremonies.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2007년도 추계 학술논문 발표대회
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• pp.67-70
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• 2007

In this study, the characteristic of strength development of high volume fly ash concrete(HVFAC) was experimentally investigated. The production of one ton of portland cement releases about 0.87ton of CO2 into the atmosphere. HVFAC is an emerging material technology and is environmentally friendly because of its reduced use of portland cement, reduced CO2 emissions. For this purpose, two levels of W/B were selected. Seven levels of fly ash replacement ratios and two levels of silica fume replacement ratios were adopted. In the concrete mix, the water content of 125kg/m3 was used, which is less than that of usual water content. As a result, it was observed that the slump of concrete was increased with the increasing fly ash replacement ratio and when the silica fume was incorporated into the concrete, the slump was significantly decreased at the same condition. It appeared that the compressive strength gradually decreased with increasing fly ash replacement ratio at the early age, but the difference of strength up to replacement ratio of 50% was little at the age of 91 days because of the pozzolanic reaction of fly ash.

• 한국건축시공학회지
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• 제12권2호
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• pp.133-141
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• 2012

As we move from the industrial age to the information age, domestic industries are changing rapidly, and rural society is also laying the foundation to make use of information technologies. Through this kind of modernization, the size of agricultural facilities has been increasing on a significant scale. But, in reality, there are many difficulties in the maintenance of agricultural facilities in proportion to their growing number. Accordingly, this research aims to solve the fundamental problems that occur with agricultural facilities in the maintenance stage. In addition, it aims to provide information on how to maintain and manage facilities for farmers. The presentation of the maintenance information was conducted using a case-based reasoning method that solves current problems based on past cases. The tool of case-based reasoning was applied to define the establishment of the base for cases, characteristic variables and maintenance measures. The effectiveness of a CBR model was examined through the case study. The use of the case-based reasoning method is judged to be effective as a tool to support the decisions of farmers regarding maintenance. When the maintenance measures derived through the CBR model are offered to farmers, the fundamental problems of maintaining agricultural facilities will be solved, and the damage to such facilities minimized.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.151-152
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• 2023

This study investigates the effect of nano-silica and nano-calcite on the hydration properties and mechanical performance of limestone calcined clay cement (LC³) paste. The pastes were synthesized by replacing limestone with nano-silica and nano-calcite in order to enhance the mechanical properties in both early and late stages of hydration. The nano-calcite enhanced the strength of LC³ pastes at 1 day of hydration, however, the strength decreased compared to the ordinary LC³ pastes afterwards due to excessive amount of carboaluminate produced in the pastes. On the other hand, nano-silica improved the mechanical properties of LC³ pastes at all ages of hydration. This is mainly due to the nucleation effect and pozzolanic reaction of nano-silica, affecting the early age and late ages of hydration, respectively. The nucleation effect of both nanomaterials were confirmed by the analysis of hydration heat, supporting the enhanced early age strength of nanomaterial incorporated LC³ pastes. Furthermore, the dense matrix was shown in the pore size distribution, and the increased C-S-H due to the pozzolanic reaction evidence the improved compressive and splitting tensile strength of nano-silica incorporated LC³ pastes.

• 한국건축시공학회지
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• 제3권1호
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• pp.85-91
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• 2003

This study aims to provide basic data that can be applied to construct real structures. For this, an experimental structure was manufactured to identify durability according to age of fiber-reinforced concrete which contains fiber reinforcement materials (polypropylene fiber, steel fiber, cellulose fiber) and structural property about flexural behavior and destruction of reinforced concrete beam, and a relation between load and deflection, crack and destruction according to increase of load and ductility capacity was examined. Fiber-reinforced concrete materials and other constructional materials were experimented and the result is presented as follows: The results obtained through material test of concrete and static experiment of members usings 1. The experiment shows that compressive strength of fiber-reinforced concrete was lower than that of non-reinforced concrete. 2. As a result of strength experiment according to different kinds of fiber, compressive strength of an experimented structure that contains cellulose fiber was the highest when age was 28. 3. When deflection of reinforced concrete beam was examined, it was reported that ductility capacity of the experimented structure that contains fiber-reinforced concrete was raise than that of non-reinforced concrete.

• 한국건축시공학회지
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• 제4권1호
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• pp.141-146
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• 2004

1) As a result of compressive strength experiment, rupture compressive strength showed more increases in specimens of 15% and 20% of Cockle shells in those of non-mixture. Comparing compressive strength between no-mixed Specimens and Specimens of containing Cockle shells, Specimens containing Cockle shells showed higher strength in 60 days and 90 days of age, and as ark Cockle is contained and age is elapsed, compressive strength is also increased In addition, estimation of compressive strength by reactive hardness in concrete using Cockle shells as aggregate shows low reliability. 2) As a result of experimenting compressive strength after heating, Specimens containing Cockle shells and non-mixed Specimens showed similar strength at $200^{\circ}C$, but compressive strength was lowered as content of Cockle shells increased at over $400^{\circ}C$ and heating temperature was higher. It is because Cockle shells was fired by heat and then its adhesion and bonding capacity were lost. 3) To sum up the above experimental results, it is found that using splitted Cockle shells as aggregate for concrete by 10%~20% showed the same or higher compressive strength and shear strength as concretes using general aggregate and it can be used as substitute aggregate of concrete. It is considered that for future use of splitted Cockle shells as substitute concrete aggregate, continuous researches of its durability, applicability and economy are needed.

• Environmental Engineering Research
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• 제23권4호
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• pp.354-363
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• 2018

We examined the levels of brominated flame-retardants (BFRs) including polybrominateddiphenyl ethers (PBDEs), tetrabromobisphenol-A (TBBPA), hexabromocyclododecane (HBCD), and phthalates in indoor dusts in residential houses in Korea, and their distribution patterns depending on building characteristics. Mean concentrations of phthalate esters ($1,825{\mu}g\;g^{-1}$) were significantly higher than that of BFRs (PBDE: $1,332ng\;g^{-1}$, HBCDs: $459ng\;g^{-1}$, and TBBPA: $213ng\;g^{-1}$), indicating more frequent use of phthalate-containing products such as PVC flooring in the Korean houses. PVC flooring house was associated with higher concentrations of DEHP (p = 0.001) and BBP (p = 0.012), indicating that exposure to phthalate was higher in the PVC flooring house. Building age was significantly related with levels of PBDEs especially BDE-47 (p = 0.062), BDE-203 (p = 0.007), DEHP (p = 0.004), and BBP (p = 0.070), respectively, indicating that older buildings can produce higher amounts of PBDEs and phthalates. Our study can provide important information on the sources of BFRs and phthalates in residential houses in Korea.

• 한국실내디자인학회논문집
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• 제22권6호
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• pp.29-39
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• 2013

Architecture has been expressed a complexity of their civilization with evolving into a living spaces and a crystalloid of culture in the times. So, architecture is always a dramatic phenomenon related to architectural aesthetic and technical expression in harmony with social and cultural issues by the times. From this point of view, we can describe that architecture is one of an important mediators to analyze the integrated trend of time. Specially an expressed building envelop which is a matter of consequence in the architectural component is first visual factor including architectural meaning and historical back ground. Therefore, this study firstly starts an investment for discriminative characteristics of building envelop design in the times, then will take the comparative analysis related with modern age and contemporary age based on phases of the times. This research will give the chance to prepare of the pillar of future envelop design in the practical affairs and has simultaneously the chance to understand of inclusive envelop design methodology by the changes of the times.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.297-298
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• 2023

In the concrete industry, efforts are being made to reduce CO₂ emissions, and technologies that collect, store, and utilize CO₂ have recently been studied. This study analyzed the change in compressive strength after the accelerated carbonation test of Non-Sintered Cement(NSC) mortar. Type C Fly Ash and Type F Fly Ash were mixed in a 1:1 ratio and then mixed with Blast Furnace Slag fine powder to produce NSC. The mortar produced was cured underwater until the target age. In addition, an accelerated carbonation test was conducted under the condition of a concentration of 5 (±1.0%) of CO₂ gas for 14 days. The mortar compressive strength was measured before and after 14 days of accelerated carbonation test based on the 7th and 28th days of age. As a result of the experiment, the compressive strength was improved in all binder. In general, the compressive strength of NSC mortar subjected to the accelerated carbonation test was similar to that of Ordinary Portland Cement(OPC) mortar not subjected to the accelerated carbonation test.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.203-204
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• 2016

In this research, it used cement power and reduction slag, which generates high hydration heat in hydration reation without heat cure below -5℃ degree. Purpose of final research is preventing freezing and thawing by making the compressive strength 5MPa in 3days below zero temperature due to own heat of concrete. and it is the result of physical characteristic and thermal property evaluation of reduction slag. Because reduction sag generates high hydration heat, compressive strength development is excellent. By generating highly Hydration heat by C₁₂A₇ and C₃A in reduction slag, compressive strength is developed in low temperature. In case of displacing only reduction slag without SO₃, it is indicated that quick-setting occurs by shortage of SO₃. For preventing quick-setting, gypsum is used essentially. According to this research result, in case of using reduction slag and gypsum as a ternary system, Compressive strength developed 5MPa in 3days below zero temperature. It is identified to prevent early frost damage of concrete below zero temperature.