• Advances in concrete construction
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• 제11권5호
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• pp.419-428
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• 2021

The pH of cement-based materials (CBMs) is an important factor for their durability, sustainability, and long service life. Currently, the use of supplementary cementitious materials (SCMs) is becoming mandatory due to economic, environmental, and sustainable issues. There is a decreasing trend in pH of CBMs due to incorporation of SCMs. The determination of numerical values of pH is very important for various low and high volume SCMs blended cement mortars for the better understanding of different defects and durability issues during their service life. In addition, the effect of cement hydration and pozzolanic reaction of SCMs on the pH should be determined at initial and later ages. In this study, the effect of low and high-volume fly ash (FA) and ground granulated ballast furnace slag (GGBFS) cement mortars in different curing conditions on their pH values has been determined. Thermal gravimetric analysis (TGA) was carried out to support the findings from pH measurements. In addition, thermal conductivity (k-value) and strength activity indices of these cement mortars were discussed. The results showed that pH values of all blended cement mortars were less than ordinary Portland cement (OPC) mortar in all curing conditions used. There was a decreasing tendency in pH of all mortars with passage of time. In addition, the pH of cement mortars was not only dependent on the quantity of Ca(OH)₂. The effect of adding SCMs on the pH value of cement mortar should be monitored and measured for both short and long terms.

• 한국강구조학회 논문집
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• 제13권2호
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• pp.177-189
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• 2001

현대 건축물들의 고층화 추세에 따라 등장한 구조물의 공사비 절감을 위한 한 방법으로 H형강보의 웨브 부분에 설비용 덕트와 배관류 등을 관통시키기 위하여 개구부를 두는 유공보를 자주 사용하고 있다. 본 연구에서는 현재 유공보의 설계에 사용되고 있는 기존의 강도식들의 문제점을 살펴보고 소성 붕괴 매커니즘에 기초를 둔 보다 합리적인 강도식을 제안하고자 한다. 제안식은 기존의 강도식들과 비교하여 볼 때 단순하며 이해하기 쉽다. 제안식의 검증은 과거에 이루어진 연구 결과들을 사용하여 평가되어 졌다. 이들 연구결과들을 근거로 제안식의 극한 강도를 비교해 볼 때 현재 실무에서 사용되어 지고있는 강도식들보다 합리적인 결과 값을 기대할 수 있다.

• 한국주거학회논문집
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• 제28권1호
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• pp.95-107
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• 2017

The purpose of the study is to analyze the planning characteristics of outdoor space in apartment complexes in terms of child-care environment. We selected 8 apartment complexes in Cheongju, within three years from construction, of small and medium-sized apartments ($60-85m^2$) where a large number of families with young children are presumed to reside in. As a result of the study, it was found that whereas the factors that can be quantified such as the floor height differences, the angles of ramps, and the number of the rest facilities are excellent, the qualitative part which cannot be easily quantified such as the location and direction of the rest facility and play materials should be improved a lot. And the following improvements were suggested; separating the pedestrian passage from the vehicle road in the main entrance of the complex, utilizing the piloti for infant caring, making the entrance area of apartment safe for pedestrians from vehicles, reallocating resting spaces, redesigning resting spaces safer to infants, building or reallocating existing booths at the stops of kindergarten buses, redesigning the square safer from vehicles with shades, making it possible for guardians to watch infants in playing field from the resting space, allocating natural environments essential for child development.

• Archives of Pharmacal Research
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• 제25권5호
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• pp.572-584
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• 2002

Rapid development in molecular biology and recent advancement in recombinant technology increase identification and commercialization of potential protein drugs. Traditional forms of administrations for the peptide and protein drugs often rely on their parenteral injection, since the bioavailability of these therapeutic agents is poor when administered nonparenterally. Tremendous efforts by numerous investigators in the world have been put to improve protein formulations and as a result, a few successful formulations have been developed including sustained-release human growth hormone. For a promising protein delivery technology, efficacy and safety are the first requirement to meet. However, these systems still require periodic injection and increase the incidence of patient compliance. The development of an oral dosage form that improves the absorption of peptide and especially protein drugs is the most desirable formulation but one of the greatest challenges in the pharmaceutical field. The major barriers to developing oral formulations for peptides and proteins are metabolic enzymes and impermeable mucosal tissues in the intestine. Furthermore, chemical and conformational instability of protein drugs is not a small issue in protein pharmaceuticals. Conventional pharmaceutical approaches to address these barriers, which have been successful with traditional organic drug molecules, have not been effective for peptide and protein formulations. It is likely that effective oral formulations for peptides and proteins will remain highly compound specific. A number of innovative oral drug delivery approaches have been recently developed, including the drug entrapment within small vesicles or their passage through the intestinal paracellular pathway. This review provides a summary of the novel approaches currently in progress in the protein oral delivery followed by factors affecting protein oral absorption.

• 국제초고층학회논문집
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• 제5권2호
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• pp.95-103
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• 2016

One of the key problems in the design of high-rise commercial complex is how to guide reasonable pedestrian distribution in commercial space. In this study, pedestrian distribution in three high-rise commercial complexes in Shanghai and Hong Kong was studied using spatial configuration analysis software Space Syntax and quantification of physical elements in commercial spaces, such as functional attractiveness, entrances, escalators, level variations and passage width. Additionally, in an attempt to integrate functions with spatial integration and spatial depth, two combination variables, the spatial coefficient of function (IF) and spatial depth coefficient of function (F/D), were proposed. The results of the correlation analysis and multiple regression analyses reflected the following: (1) Regarding the influence on pedestrian distribution, there was a synergistic and complementary relationship between function and space; (2) The comprehensive flow distribution analytic model could successfully interpret flow distribution in high-rise commercial complexes and its R Square ranged up to about 70% in the three cases; (3) The spatial coefficient of function (IF) and spatial depth coefficient (F/D) could effectively integrate functions and spatial configuration, which could help close the gap between over-emphasis on function in commercial research and the lack of consideration of function in space-syntax analysis.

• KIEAE Journal
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• 제9권6호
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• pp.27-36
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• 2009

Lately construction companies are differentiating the outdoor spaces of apartment complexes to satisfy the needs of residents by providing underground parking area and variety of outdoor community spaces. Building walking networks through residential unit area, the major passage area and the entrance area of the complexes is very important factor to increase the use of the outdoor environment in the complexes. The purpose of this study is to evaluate the characteristics and the elements for the planning of exterior pedestrian spaces carefully through the analysis of current large-scale apartment complexes. In this study, the utilization of space, the connectivity to other spaces and the application of Universal design were evaluated through site visits in 5 large-scale apartment complexes. As a result, the utilization of space is well applied in the most of complexes especially in residential unit area. The connectivity to other spaces has low application compared to the others. Universal design is also well applied except sub criteria for the blind in most of complexes. This study will be able to help in providing better exterior pedestrian environment for residents in apartment complexes.

• 건축역사연구
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• 제19권6호
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• pp.61-78
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• 2010

Old Russian Legation(1890) has been attracted public attention in terms of politics and foreign affairs than architectural style because of conditions of location and historical incident. Though it was heavily damaged during the Korean war, and only the tower has been restored, it is very important in architectural history in Korea, because it is the oldest western style brick building which is existing with the old bishop's house in Myeong-Dong. But it has been impossible to reveal exactly the original form as there has been few reliable materials(picture, drawing, document) and it's remains were nearly destroyed owing to development of the surroundings. Recently the decisive document(site outline map) was found, and new research on the architect Sabatine was studied. So I can get into close with the original form by the results. In this study, I tried to conjecture the original form of the old Russian legation(the size, style, plan and indoor space, arrangement of attached facilities) and I checked the location and structure of the room where King Gojong stayed when he took refuge, and the use of the passage in the basement.

• 한국전기전자재료학회논문지
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• 제33권6호
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• pp.471-474
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• 2020

In recent years, the challenge of higher energy efficiency has emerged as urban buildings have become taller, and the area of window glasses has increased. To address the problem of energy efficiency in buildings, research on smart windows is being actively conducted. In this study, an accelerated experiment for thermal stability was conducted to fabricate a liquid crystal cell applicable to external windows. It was confirmed from the study that the function is maintained even in a high-temperature external environment through the change in transmittance by voltage. Compared with the initial transmittance, after the passage of time, the smart window cell to which the sealant was applied showed a small change in transmittance of 1~2%. This result confirmed the thermal stability of the liquid crystal-based smart window.

• 지식경영연구
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• 제20권3호
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• pp.139-154
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• 2019

With the increasing use of smartphone apps, many apps are coming out in various fields. In order to analyze the current status and trends of apps in a specific field, it is necessary to establish a classification scheme. Various schemes considering users' behavior and characteristics of apps have been proposed, but there is a problem in that many apps are released and a fixed classification scheme must be updated according to the passage of time. Although it is necessary to consider many aspects in establishing classification scheme, it is possible to grasp the trend of the app through the proposal of a classification scheme according to the characteristic of the app. This research proposes a method of establishing an app classification scheme through the description of the app written by the app developers. For this purpose, we collected explanations about apps in the tourism field and identified major categories through topic modeling. Using only the apps corresponding to the topic, we construct a network of words contained in the explanatory text and identify subcategories based on the networks of words. Six topics were selected, and Clauset Newman Moore algorithm was applied to each topic to identify subcategories. Four or five subcategories were identified for each topic.

• 대한안전경영과학회지
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• 제26권1호
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• pp.63-74
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• 2024

The objectives of this study is to classify evacuation types, derive the characteristics of 4 types, develop and discover evacuation routes within the performance hall space, and present the statistical classification results of the evacuation classification model by classification type. To achieve this purpose, the characteristics of each evacuation type's four types are applied through a network reliability analysis method and utilized for institutional improvement and policy. This study applies for the building law, evacuation and relief safety standards when establishing a performance hall safety management plan, and reflects it in safety-related laws, safety standards, and policy systems. Statistical data by evacuation type were analyzed, and measurement characteristics were compared and analyzed by evacuation types. Evaluate the morphological similarity and reliability of evacuation types according to door width and passage length and propose the install position of evacuation guidance sign boards. The results of this study are expected to be used as basic data to provide operation strategies for safety facility evacuation information sign boards according to evacuation route classification types when taking a safety management plan. The operation strategy for the evacuation sign boards installation that integrates employee guidance and safety training is applied to the performance hall safety management plan. It will contribute to establishing an operational strategy for performance space safety when constructing performance facilities in the future.