• 한국건축시공학회지
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• 제10권4호
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• pp.113-122
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• 2010

In this study, 150MPa ultra-high-strength concrete was manufactured, and its performance was reviewed. As technically meaningful autogenous shrinkage reportedly occurs at a W/B ratio of 40% or less, although it occurs in all concrete regardless of the W/B ratio, the effects of the use of expansive admixture and shrinkage reducer, or of the friction and restraint of forms that may result in the effective reduction of autogenous shrinkage, were reviewed. As a result, considering the flow and strength characteristics, it was found that the slump flow time was shorter with expansive admixture, and shortest with shrinkage reducer. All specimens with $30kg/m^3$ expansive admixture showed high strength at early material age. Their strength decreased due to the expansion cracks when there was excessive use of expansive admixture, and the use of shrinkage reducer did not influence the change in the strength according to the material age. The expansive admixture had a shrinkage reduction effect of 80%, while the shrinkage reducer had a shrinkage reduction effect of 30%, indicating that the expansive admixture had a stronger effect. It seems that mixing the two will have a synergistic effect. The shrinkage reduction rate was highest when the W/B ratio was 20%. The form suppressed the expansion and shrinkage at the early period, and the demolding time did not significantly influence the shrinkage. The results of the study showed that the excessive addition of expansive admixture leads to expansion cracks, and the expansive admixture and shrinkage reducer have the highest shrinkage reduction effect when they are mixed.

• 대한토목학회논문집
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• 제31권3D호
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• pp.375-381
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• 2011

본 연구는 ITS(Intelligent Transport Systems) 기술 중 버스대중교통의 신속성 및 정시성 등 서비스 향상을 위해 구축된 버스정보시스템(BIS: Bus Information System) 운영에 대한 $CO_2$ 저감효과를 분석하였다. IPCC에서는 $CO_2$ 저감효과 분석을 위해 3가지 방법을 제시하고 있으며, 이 중 가장 구체적인 Tier 3 방법을 활용하고자 하였다. 분석은 대전-청주 간 BIS 구축 노선 중 8.3km 구간에 대하여 진행되었으며, Tier 3 방법에 필요한 교통 관련 자료는 ITS 기반으로 수집된 자료를 활용하였다. 분석결과, BIS사업 시행에 따른 $CO_2$ 저감효과는 연간 $39.45tCO_2/km$가 있는 것으로 나타났다. 이러한 $CO_2$ 저감효과는 향후 BIS 사업의 효과척도로 사용 가능할 것으로 판단된다.

• 한국태양에너지학회 논문집
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• 제28권5호
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• pp.14-20
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• 2008

As the number of buildings that use the transparent permeation materials as the outer wall is on the increase, the coming amount of the light rays is a lot, and thus the increase in the cooling load and the radiant heat of high temperature may cause the residents to discomfort. In order to reduce such influences, this paper analyzed the installation effects of the sunshade BIPV. The inner temperature of the room installed the sunshade BIPV or otherwise was measured, and compared and analyzed the effects of reducing the cooling load by the incoming light rays. The sample space of the third floor of S university installed the sunshade BIPV has two rooms on the same conditions, and for five sunny days selected in August, the researcher measured the air temperature and the temperature of the fittings with closing the windows to minimize the movement of air without operating the coolers. The maximum cooling load measured by the incoming light rays in the room where the sunshade BIPV was not installed was examined as 459.13kcal/h. It can be understood as the effect of reducing the cooling load according to the incoming rays of the room with sunshade BIPV. Even though the effect of cooling load reduction is not so great in a room, the total reduction in cooling room for the 32 rooms installed the sunshade BIPV was estimated to be 40442.27kcal/day, which will be able to bring the maximum reduction effect of 17.1kW in energy and reduce the investment cost owing to the reduction in cooling load when initially designing the building.

• 무역학회지
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• 제46권5호
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• pp.195-211
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• 2021

The purpose of this study is to examine the relationship among innovation activities, innovation performance, and management performance of export firms. I first undertake a review of previous studies related to innovation activity, innovation performance, and export firms' innovation. Based on this, I set up a research model and hypotheses. First, The innovation activity is classified into product innovation activity, process innovation activity, and administrative innovation activity. Innovation performance is divided into product quality improvement and cost reduction. And the business performance is regarded as financial performance of export's firms. This study examined whether innovation activity affect innovation performance such as product quality improvement and cost reduction. In addition, I examined whether these innovation performance affects business performance (financial performance). To achieve this, a total of 368 questionnaires are used in this study and PLS (Partial Least Square) was used to analyze structural equation. As a result, this study shows that product innovation activity have a positive effect on product quality improvement, and process innovation activity also have a positive effect on product quality improvement. However, it was found that neither product innovation activity nor process innovation activity had an effect on cost reduction. And it was found that administrative innovation did not affect product quality improvement, but had a positive effect on cost reduction. Also, it was found that quality improvement, which is an innovation performance, did not affect the financial performance of export's firms, and cost reduction, which is an innovation performance, had a positive effect on the financial performance of the export's firms.

• 한국디지털건축인테리어학회논문집
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• 제11권2호
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• pp.83-92
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• 2011

The purpose of this study is to propose strategies for reducing greenhouse gas emissions on urban areas. This study is made up GHG emission estimation and emission prospect methods, setting of GHG reduction target, GHG reduction plan formulation and feasibility assessment. The significance of this study is as follows. First, this study provides the local government for the overall frame of low carbon strategies. Second, this study contribute to establishment of GHG emission reduction strategies in the local autonomy by providing GHG emission estimation and setting reduction target which is essential elements of reduction strategy. Third, we organize a reduction element for low carbon city embodiment and showed the way to assessment the reduction effect of these elements quantitatively.

• KIEAE Journal
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• 제14권2호
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• pp.87-98
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• 2014

This study is to identify quantitatively the function of carbon dioxide emissions reduction due to temperature and energy reduction according to direct carbon dioxide storage, shade provision, and evaportanspiration of urban park. According to the result of study, landscape tree indicated high carbon dioxide storage effect compare to bush, in which broadleaf tree indicated higher storage function than coniferous tree. It is believed to be the storage of carbon dioxide can be increased by increasing the composition rate of forest plants in the urban park. According to the direct estimation result of carbon dioxide storage in terms of example area, storage of carbon dioxide is estimated to be "seoul a zone" $476,818.8kg{\cdot}CO_2/m^2yr$, "anyang b zone" $186,435.7{\cdot}CO_2/m^2yr$, "daejeon c zone" $262,826{\cdot}CO_2/m^2yr$, "kwangju d zone" $231,657.8{\cdot}CO_2/m^2yr$. The carbon dioxide storage per unit area estimated to be "seoul a zone" $3.4{\cdot}CO_2/m^2yr$, "anyang b zone" $5.0{\cdot}CO_2/m^2yr$, "daejeon c zone" $2.6{\cdot}CO_2/m^2yr$, "kwangju d zone" $5.6{\cdot}CO_2/m^2yr$. The result of indirect carbon dioxide reduction effect estimated to be "seoul a zone" $291,603.4{\cdot}CO_2/m^2yr$, "anyang b zone" $165,462.4{\cdot}CO_2/m^2yr$, "daejeon c zone" $141,719.2{\cdot}CO_2/m^2yr$, "kwangju d zone" $154,803.4{\cdot}CO_2/m^2yr$. Carbon dioxide reduction potential amount through the urban park was increased to 1.6 times to 1.8 times when calculated to the indirect effect.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제2권1호
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• pp.35-42
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• 2013

본 논문은 정보통신기술을 기반으로 한 특정 서비스가 온실가스 감축에 미치는 영향력에 대하여 실험을 통하여 실증적으로 보여준다. 본 연구에서는 정보통신기술 기반 서비스로 실시간내비게이션을 선정하여 최적경로의 이산화탄소 감소율을 기존 내비게이션에서 제공하는 최단경로에서의 이산화탄소 감소율과 비교 실험하였다. 실험 결과는 실시간내비게이션의 최적경로로 이동할 경우 최단거리에 비해 이산화탄소 배출량 감소의 효과가 있다는 것을 보여준다. 또한, 본 연구는 청정개발체제에서 제시하는 온실가스 감축 방법을 기반으로 정량화 및 모니터링 접근을 통한 새로운 온실가스 감축 평가 방법을 이론적으로 제시하였다. 본 연구의 결과는 다양한 정보통신기술 기반 서비스들의 온실가스 감축 영향력에 대한 연구의 기반연구로써 활용될 수 있을 것이다. 또한, 본 논문에서 제시한 온실가스 감축 평가 방법론은 청정개발체제에 제안되어 새로운 표준으로 활용될 수 있을 것이다.

• 한국프랜차이즈경영연구
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• 제13권3호
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• pp.45-55
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• 2022

Purpose: Consumers' experience of functional attributes is remembered, and the experience lowers the cost of consumers' input from their point of view and reduces uncertainty. It also plays an important role in consumers' positive emotions and responses. Accordingly, if information search costs are reduced in terms of the costs perceived by consumers about restaurants, a strategy differentiated from other companies can be established. Therefore, this study investigated the effect of functional congruence of restaurant stores on information search cost reduction, positive/negative emotions, and loyalty. Research Design, Data, and Methodology: This study investigated functional congruence, information search cost reduction, and positive/negative emotions. The structural relationship between loyalty was analyzed. To verify this, a research hypothesis was established based on previous studies and a research model was constructed. The questionnaire items were modified and used according to the current study, based on previous studies. The data were collected using the questionnaire method from 187 people who had dining out experience. Frequency analysis was performed to confirm demographic characteristics. Reliability, convergent validity, and discriminant validity of the collected data were verified. The research model was analyzed with a structural equation modeling (SmartPLS 4). Results: The findings show that functional congruence had significant positive effects on information search cost reduction and positive emotion, but no significant effect on negative emotion. Information search cost reduction had significant positive effects on positive emotion/negative emotion but did not significantly affect loyalty. Lastly, both positive and negative emotions had significant positive effects on loyalty. Conclusion: Based on transaction cost theory, this study found how functional congruence and information search cost reduction influence consumers' emotions. The functional attributes of restaurants were perceived by customers as information, thus uncertainty was decreased. Finally, appropriate management strategies and implications of functional congruence and information search cost in the restaurant were suggested.

• 소음진동
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• 제3권4호
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• pp.325-330
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• 1993

The longitudinal vibration of the tape in the tape transport system influences the performance of the nagnetic tape-recording system. Generally it is controlled by a passive method with impedance roller which is easy to implement and cost-effective. Therefore the effect of the impedance roller in reducing the tape vibration was analyzed in this paper. The practical tape transport system was modelled mathematically as a mass-spring system. Both simulation and experimental study were carried out in order to show the vibration reduction effect of the impedance roller.

• Journal of Biosystems Engineering
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• 제36권5호
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• pp.342-347
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• 2011

The effect of SNC(silver nano colloid) on the emission reduction of odors such as ammonia ($NH_3$), hydrogen sulfide ($H_2S$), and methane ($CH_4$) from swine excreta was studied. Silver has been used as an universal antibiotic substance and can reduce the emission of some gases by sterilizing action. Therefore, an apparatus which produces SNC was developed and was conducted its performance test. Also, the SNC made by the apparatus was applied to swine excreta sampled from a piggery in oder to find the effect on the reduction of odor emission. An electrolysis apparatus was developed to produce SNC and its capacity was 0.024 ppm/$hr{\cdot}L$. The effects of SNC on the reduction of odor emission from swine excreta were tested for bad smell gases of ammonia ($NH_3$), hydrogen sulfide ($H_2S$) and methane ($CH_4$). For ammonia gas, factorial experiments were conducted to find the effects of concentration and application rate of SNC. The test results for the different concentrations of 20 ppm, 50 ppm, and 100 ppm showed that the more concentration of SNC was increased, the more emission reduction of ammonia gas increased. From the test results about the effect of application rate, the more SNC was applied, the more emission reduction of $NH_3$ increased. In order to reduce the concentration of $NH_3$ below 5 ppm, SNC of 50 ppm is recommended to be applied at an interval of 6 hours, and is mixed with swine excreta in the volumetric ratio of 4:1. For hydrogen sulfide gas, the concentration was decreased as time went by and was reduced rapidly in the first stage of the tests for all applied concentrations of SNC (20 ppm, 50 ppm, and 100 ppm). Especially, when 100 ml of SNC with 100 ppm was applied, emission of hydrogen sulfide gas was reduced rapidly during early 4 hours after the application of SNC. And, concentration of hydrogen sulfide gas was maintained below 20 ppm after 12 hours. For methane gas, t-test showed that there was no significance on the effect of its application for all applied concentrations of SNC. Therefore, it was concluded that the application of SNC on swine excreta had no effect on the emission reduction of $CH_4$.