• Title/Summary/Keyword: Concrete properties

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Analysis on Media Reports of the 「Security Services Industry Act」 Using News Big Data -Focusing on the Period from 1990 to 2021-

  • Cho, Cheol-Kyu;Park, Su-Hyeon
    • Journal of the Korea Society of Computer and Information
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    • v.27 no.5
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    • pp.199-204
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    • 2022
  • The purpose of this study is to broaden the understanding of the Security Services Industry Act, and also to examine the meanings of various phenomena by analyzing the media report big data rather than the researchers' perspective on the Security Services Industry Act. In the research method, this study searched for a keyword 「Security Services Industry Act」 that prescribes the security work as an important subject of crime prevention and maintenance of public order in Korea. The data was searched from 1990 to 2021 the BIG KINDS could provide. Also, for the concrete analysis during the period of data search, it was divided into settlement period(1976~2001), growth period-quantitative(2002~2012), and growth period-qualitative(2013~2021). In the results of this study, the media report perception of the Security Services Industry Act is continuously emphasizing the social roles and importance of private security according to the flow of time. The consequent marketability of private security will play great roles in the protection of people's lives and properties in the combination with various other industries in the future. However, the private security industry that provides public peace service together with the police, could be rising as an element that hinders the development of private security industry because of various social issues caused by legal regulations and illegal problems, so it would be necessary to more strengthen its responsibility and roles accordingly.

An accurate analytical model for the buckling analysis of FG-CNT reinforced composite beams resting on an elastic foundation with arbitrary boundary conditions

  • Aicha Remil;Mohamed-Ouejdi Belarbi;Aicha Bessaim;Mohammed Sid Ahmed Houari;Ahmed Bouamoud;Ahmed Amine Daikh;Abderrahmane Mouffoki;Abdelouahed Tounsi;Amin Hamdi;Mohamed A. Eltaher
    • Computers and Concrete
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    • v.31 no.3
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    • pp.267-276
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    • 2023
  • The main purpose of the current research is to develop an efficient two variables trigonometric shear deformation beam theory to investigate the buckling behavior of symmetric and non-symmetric functionally graded carbon nanotubes reinforced composite (FG-CNTRC) beam resting on an elastic foundation with various boundary conditions. The proposed theory obviates the use to shear correction factors as it satisfies the parabolic variation of through-thickness shear stress distribution. The composite beam is made of a polymeric matrix reinforced by aligned and distributed single-walled carbon nanotubes (SWCNTs) with different patterns of reinforcement. The material properties of the FG-CNTRC beam are estimated by using the rule of mixture. The governing equilibrium equations are solved by using new analytical solutions based on the Galerkin method. The robustness and accuracy of the proposed analytical model are demonstrated by comparing its results with those available by other researchers in the existing literature. Moreover, a comprehensive parametric study is presented and discussed in detail to show the effects of CNTs volume fraction, distribution patterns of CNTs, boundary conditions, length-to-thickness ratio, and spring constant factors on the buckling response of FG-CNTRC beam. Some new referential results are reported for the first time, which will serve as a benchmark for future research.

The Case Study of Design on Steel Pipe Sheet Pile for Earth Retaining Wall on Deep Excavation (대심도 지반굴착을 위한 벽강관말뚝 흙막이공법의 설계 사례 연구)

  • Byung-Il Kim;Jong-Ku Lee;Kyoung-Tae Kim;Kang-Han Hong;Sang-Jae Han
    • Journal of the Korean Geosynthetics Society
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    • v.22 no.1
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    • pp.53-66
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    • 2023
  • In this study, the results of the elasto-plastic beam analysis, finite element analysis and optimization design of the steel pipe sheet pile applied as an earth retaining wall under the deep excavation were presented. Through this study, it was found that the high-strength and sea resistant steel pipe has high allowable stress, excellent structural properties, favorable corrosion, and high utilization as an earth retaining wall, and the C-Y type joint has significantly improved the tensile strength and stiffness compared to the traditional P-P type. In addition, it was investigated that even if the leak or defect of the wall occurs during construction, it has the advantage of being able to be repaired reliably through welding and overlapping. In the case of steel pipe wall, they were evaluated as the best in views of the deep excavation due to the large allowable bending stress and deformation flexibility for the same horizontal displacement than CIP or slurry wall. Elasto-plastic and finite element analysis were conducted in consideration of ground excavation under large-scale earth pressure (uneven pressure), and the results were compared with each other. Quantitative maximum value were found to be similar between the two methods for each item, such as excavation behavior, wall displacement, or member force, and both analysis method were found to be applicable in design for steel pipe sheet pile wall. Finally, it was found that economical design was possible when determining the thinnest filling method with concrete rather than the thickest hollow shape in the same diameter, and the depth (the embedded length through normality evaluation) without rapidly change in displacement and member force.

Possibility of Using Landfill Coal Ash as CLSM Material for Emergency Restoration of Ground and Road Joint Parts (지반 및 도로 공동부의 긴급복구용 CLSM 재료로 매립 석탄저회 활용 가능성)

  • Jin-Man Kim;Sang-Chul Shin;Kyoung-Nam Min;Ha-Seog Kim
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.11 no.1
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    • pp.55-61
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    • 2023
  • This study aims to develop CLSM fill material for emergency restoration using landfill coal ash. As a result of examining physical properties such as particle size distribution and fines content of landfill coal ash, bottom ash, fly ash, and general soil were mixed, and SP was found to have a density of 2.03 and a residual particle pass rate of 7.8 %. CLSM materials that secure fluidity in unit quantities without using chemical admixtures such as glidants and water reducing agents have a high risk of material separation due to bleeding. As a result of this experiment, it was found that the bleeding ratio did not satisfy the standard in the case of the specimen with a large amount of fly ash and a lot of addition of mixing water. As a result of the compressive strength test, the strength development of 0.5 MPa or more for 4 hours was found to be satisfactory for the specimens using hemihydrate gypsum with a unit binder amount of 200 or more, and the remaining gypsum showed poor strength development. Although it is judged that landfill coal ash can be used as a CLSM material, it is necessary to identify and apply the physical and chemical characteristics of coal ash buried in the ash treatment plant of each power generation company.

An Experimental Study on the Carbonation Depth of Cement Paste Using Carbonation Reaction Accelerator (탄산화 반응 촉진제를 이용한 시멘트 페이스트의 탄산화 깊이에 관한 실험적 연구)

  • Seok-Man Jeong;Wan-Hee Yang;Dong-Cheol Park
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.11 no.4
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    • pp.349-354
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    • 2023
  • This study wa s conducted a s pa rt of ma ximizing the use of ca rbon dioxide by a pplying CCU(Ca rbon Ca pture, Utiliza tion) a mong technologies for reducing CO2 in the cement industry. In a carbon dioxide curing environment, changes in carbonation depth and changes in basic physical properties by age due to the mixing of carbonation reaction accelerators were usually targeted at Portland cement paste. In addition, in order to check the fixed amount of CO2 in the concrete field, a thermal analysis method was applied to evaluate CaCO3 decarbonization at high temperatures. As a result of the evaluation, it was confirmed that the carbonation depth in the cured body significantly increased due to the incorporation of CRA in the carbonation depth diffusion performance. In addition, it was confirmed that the weight reduction rate increased by 23.8 % and 40.77 %, respectively, compared to Plain, in the order of curing conditions for constant temperature and humidity and curing conditions for carbonation chambers, so it was confirmed that the amount of excellent CaCO3 produced by the addition of CRA increased as the concentration of CO2 increased.

Assessment of Applicability of CNN Algorithm for Interpretation of Thermal Images Acquired in Superficial Defect Inspection Zones (포장층 이상구간에서 획득한 열화상 이미지 해석을 위한 CNN 알고리즘의 적용성 평가)

  • Jang, Byeong-Su;Kim, YoungSeok;Kim, Sewon ;Choi, Hyun-Jun;Yoon, Hyung-Koo
    • Journal of the Korean Geotechnical Society
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    • v.39 no.10
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    • pp.41-48
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    • 2023
  • The presence of abnormalities in the subgrade of roads poses safety risks to users and results in significant maintenance costs. In this study, we aimed to experimentally evaluate the temperature distributions in abnormal areas of subgrade materials using infrared cameras and analyze the data with machine learning techniques. The experimental site was configured as a cubic shape measuring 50 cm in width, length, and depth, with abnormal areas designated for water and air. Concrete blocks covered the upper part of the site to simulate the pavement layer. Temperature distribution was monitored over 23 h, from 4 PM to 3 PM the following day, resulting in image data and numerical temperature values extracted from the middle of the abnormal area. The temperature difference between the maximum and minimum values measured 34.8℃ for water, 34.2℃ for air, and 28.6℃ for the original subgrade. To classify conditions in the measured images, we employed the image analysis method of a convolutional neural network (CNN), utilizing ResNet-101 and SqueezeNet networks. The classification accuracies of ResNet-101 for water, air, and the original subgrade were 70%, 50%, and 80%, respectively. SqueezeNet achieved classification accuracies of 60% for water, 30% for air, and 70% for the original subgrade. This study highlights the effectiveness of CNN algorithms in analyzing subgrade properties and predicting subsurface conditions.

Basic Characteristics of ALC using Carbon dioxide Conversion Capture Materials (이산화탄소전환탄산화물 혼합 경량기포 콘크리트의 기초 특성)

  • Hye-Jin Yu;Sung-Kwan Seo;Yong-Sik Chu;Woo-Sung Yum;Kuem-Dan Park;Young-Gon Kim;Eun-Sung Yoo
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.12 no.2
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    • pp.121-127
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    • 2024
  • In this study, the applicability of replacing DG(Desulfurized Gypsum) from oil refinery with CCCMs(Carbon dioxide Conversion Capture Materials) as an ALC(Auto-claved LIghtweight Concrete) raw material was examined, and basic properties of ALC was measured. The main chemical components of DG and CCCMs were CaO and SO3, and an increase in LOI(Loss of ignition) due to mineral carbonation reaction was verified. The crystalline phases of CCCMs were CaCO3, CaSO4, Ca(OH)2, and CaSO4·2H2O. When DG, a raw material for ALC production, was replaced with CCCMs, foaming height, pore shape, absolute dry gravity, and compressive strength results measured similar for all binders. In addition, the formation of tobermorite which is main crystalline phase of ALC was shown for all specimens in microstructural analysis.

Inferential Structure and Reality Problem in Diagnosis of Oriental Medicine (한의 진단의 추론형식과 실재성)

  • Park, Geong-Mo;Choi, Seong-Hoon;Ahn, Gyu-Seok
    • Journal of The Association for Neo Medicine
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    • v.2 no.1
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    • pp.55-84
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    • 1997
  • Inferential structure and reality problem is a serious issue to O.M.(oriental medicine). The study will analyze this issue through a philosophical and historical comparative study of W.M.M(Western modern medicine) and O.M. First, I presuppose some basic ideas. The first is the division of the 'the philosophy of medicine' and 'the medicine itself'. Second, there is a 'visibility' that discriminate between 'the abstractive concept' and 'the concrete object' in diagnostic terminology. The third is the separation of disease, the entity and disease, the phenomenon. Finally, the distinction between the cause of disease and the nature of disease. Through these basic concepts, this study will analyze O.M's diagnostic methodology, 'Pattern identification of the S.A.S(sign and symptom)'. The results are follows: 1. O.M's views disease as a phenomenon. So, the S.A.S, which is visible, is the disease itself. Tough the analysis and inference of the S.A.S, 證(zheng) the essence is derived. 2. 證(zheng) can be considered as 'the abstractive concept' reflecting the essence of a disease. 3. 證(zheng) is not arrived through causal sequence reasoning but rather by analogical reasoning. 4. 證(zheng) is 'the non-random correlative combination of S.A.S', pattern. These patterns secure the abstractive deduction in reality. that is, The causality, the positivism, the view of disease as entity, and anatomical knowledge are the traits peculiar to W.M.M. But, these properties can not be applied universally to every medical systems. Also, these properties do not indicate the superiority or inferiority of any medical system. 5. 證(zheng) summarizes the patients condition simultaneously with the S.A.S. However, 證(zheng) doesn't necessarily indicate the knowledge about the actual internal organ. That is, Early in O.M.'s history, the diagnostic terminologies including 證(zheng) were analogical reflections of a naive knowledge of internal organs and external environmental factors. Later, the naive knowledge in 證(zheng) changed int new nature, an abstractive concept. The confusion of the concept of disease, the indiscriminate acceptance of Western anatomical knowledge, and the O.M.'s theoretical evolution et are the challenge facing modern O.M. To find solutions, this study looks at the sequence of the birth of W.M.M. and then compares it's system with the O.M. system. The confusion of the concept of disease, the indiscriminate acceptance of Western anatomical knowledge, and the O.M.'s theoretical evolution et are the challenge facing modern O.M. To find solutions, this study looks at the sequence of the birth of W.M.M. and then compares it's system with the O.M. system. It is recommended that O.M. diagnostics should pay close attention to the ambiguity of the diagnostic methodology in order to further development. At present time, the concept and the system peculiar to O.M. can not be explained by common language. but O.M.'s practitioner can not persist in this manner an: longer. Along with the internal development of O.M., the adjustment of O.M.'s diagnostic terminology needs to be adopted.

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Assessment of Fertilizer Efficiency of Pharmaceutical Byproduct and Cosmetic Industry Wastewater Sludge as Raw Materials of Compost (제약업종 부산물 및 화장품 제조업 폐수처리오니의 비효검정)

  • Lim, Dong-Kyu;Kwon, Soon-Ik;Lee, Seung-Hwan;So, Kyu-Ho;Sung, Ki-Suk;Koh, Mun-Hwan
    • Korean Journal of Soil Science and Fertilizer
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    • v.38 no.2
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    • pp.108-117
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    • 2005
  • Pharmaceutical byproduct sludge and cosmetic industry wastewater sludge can be used as a raw material of compost. Effects of three types of pharmaceutical byproduct sludge and one type of cosmetic industry wastewater sludge on soil properties and red pepper growth were investigated in a field based concrete pot ($2{\times}2m$). These sludges and pig manure ($5Mg\;ha^{-1}$, dry basis) were incorporated into the upper of loam soil 30 days prior to transplanting red pepper. Changes in soil properties and contents of heavy metals and toxic organic compounds in soil and plant were measured. And also plant growth measurement and bioassay of soil phytotoxicity were included. Contents of heavy metals were increased in the soils treated with the sludges. Plant growth in the sludge treatments were mostly inferior to that of NPK treatment, especially in early stage. Content of N in plant was lower in all sludge treatments at early and middle growth stages, and it was especially caused by characteristics and concentration of nitrogen and organic matter of sludges. Total yield of red pepper was highest in the NPK treatment and followed by pharmaceutical sludge 3, pig manure, pharmaceutical sludge 1, and pharmaceutical sludge 2, and the yield of cosmetic sludge treatment was considerably lower than others. HEM and PAHs contents in soil of cosmetic sludge treatment were $4.80mg\;kg^{-1}$ and $2,263.2{\mu}g\;kg^{-1}$, respectively. Root elongation of lettuce exposed to the water extract of soil treated with cosmetic sludge was about 20% of that found in the test with soil extract of non fertilization treatment. At present, raw materials of compost were authorized according to the contents of organic matter, heavy metals and product processing. Toxic organic compounds analysis and bioassay would be helpful for authorization and assessment of suitability of raw materials of compost.

A Folksonomy Ranking Framework: A Semantic Graph-based Approach (폭소노미 사이트를 위한 랭킹 프레임워크 설계: 시맨틱 그래프기반 접근)

  • Park, Hyun-Jung;Rho, Sang-Kyu
    • Asia pacific journal of information systems
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    • v.21 no.2
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    • pp.89-116
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    • 2011
  • In collaborative tagging systems such as Delicious.com and Flickr.com, users assign keywords or tags to their uploaded resources, such as bookmarks and pictures, for their future use or sharing purposes. The collection of resources and tags generated by a user is called a personomy, and the collection of all personomies constitutes the folksonomy. The most significant need of the folksonomy users Is to efficiently find useful resources or experts on specific topics. An excellent ranking algorithm would assign higher ranking to more useful resources or experts. What resources are considered useful In a folksonomic system? Does a standard superior to frequency or freshness exist? The resource recommended by more users with mere expertise should be worthy of attention. This ranking paradigm can be implemented through a graph-based ranking algorithm. Two well-known representatives of such a paradigm are Page Rank by Google and HITS(Hypertext Induced Topic Selection) by Kleinberg. Both Page Rank and HITS assign a higher evaluation score to pages linked to more higher-scored pages. HITS differs from PageRank in that it utilizes two kinds of scores: authority and hub scores. The ranking objects of these pages are limited to Web pages, whereas the ranking objects of a folksonomic system are somewhat heterogeneous(i.e., users, resources, and tags). Therefore, uniform application of the voting notion of PageRank and HITS based on the links to a folksonomy would be unreasonable, In a folksonomic system, each link corresponding to a property can have an opposite direction, depending on whether the property is an active or a passive voice. The current research stems from the Idea that a graph-based ranking algorithm could be applied to the folksonomic system using the concept of mutual Interactions between entitles, rather than the voting notion of PageRank or HITS. The concept of mutual interactions, proposed for ranking the Semantic Web resources, enables the calculation of importance scores of various resources unaffected by link directions. The weights of a property representing the mutual interaction between classes are assigned depending on the relative significance of the property to the resource importance of each class. This class-oriented approach is based on the fact that, in the Semantic Web, there are many heterogeneous classes; thus, applying a different appraisal standard for each class is more reasonable. This is similar to the evaluation method of humans, where different items are assigned specific weights, which are then summed up to determine the weighted average. We can check for missing properties more easily with this approach than with other predicate-oriented approaches. A user of a tagging system usually assigns more than one tags to the same resource, and there can be more than one tags with the same subjectivity and objectivity. In the case that many users assign similar tags to the same resource, grading the users differently depending on the assignment order becomes necessary. This idea comes from the studies in psychology wherein expertise involves the ability to select the most relevant information for achieving a goal. An expert should be someone who not only has a large collection of documents annotated with a particular tag, but also tends to add documents of high quality to his/her collections. Such documents are identified by the number, as well as the expertise, of users who have the same documents in their collections. In other words, there is a relationship of mutual reinforcement between the expertise of a user and the quality of a document. In addition, there is a need to rank entities related more closely to a certain entity. Considering the property of social media that ensures the popularity of a topic is temporary, recent data should have more weight than old data. We propose a comprehensive folksonomy ranking framework in which all these considerations are dealt with and that can be easily customized to each folksonomy site for ranking purposes. To examine the validity of our ranking algorithm and show the mechanism of adjusting property, time, and expertise weights, we first use a dataset designed for analyzing the effect of each ranking factor independently. We then show the ranking results of a real folksonomy site, with the ranking factors combined. Because the ground truth of a given dataset is not known when it comes to ranking, we inject simulated data whose ranking results can be predicted into the real dataset and compare the ranking results of our algorithm with that of a previous HITS-based algorithm. Our semantic ranking algorithm based on the concept of mutual interaction seems to be preferable to the HITS-based algorithm as a flexible folksonomy ranking framework. Some concrete points of difference are as follows. First, with the time concept applied to the property weights, our algorithm shows superior performance in lowering the scores of older data and raising the scores of newer data. Second, applying the time concept to the expertise weights, as well as to the property weights, our algorithm controls the conflicting influence of expertise weights and enhances overall consistency of time-valued ranking. The expertise weights of the previous study can act as an obstacle to the time-valued ranking because the number of followers increases as time goes on. Third, many new properties and classes can be included in our framework. The previous HITS-based algorithm, based on the voting notion, loses ground in the situation where the domain consists of more than two classes, or where other important properties, such as "sent through twitter" or "registered as a friend," are added to the domain. Forth, there is a big difference in the calculation time and memory use between the two kinds of algorithms. While the matrix multiplication of two matrices, has to be executed twice for the previous HITS-based algorithm, this is unnecessary with our algorithm. In our ranking framework, various folksonomy ranking policies can be expressed with the ranking factors combined and our approach can work, even if the folksonomy site is not implemented with Semantic Web languages. Above all, the time weight proposed in this paper will be applicable to various domains, including social media, where time value is considered important.