• Title/Summary/Keyword: Life Time value

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A Study on Improvement of Evacuation Safety Evaluation for Performance Based Design in Underground Parking Lot (지하주차장 성능위주설계의 피난안전성 평가 개선에 관한 연구)

  • Song, Young-Joo;Kong, II-Chean;Kim, Hak-Jung
    • Fire Science and Engineering
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    • v.33 no.2
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    • pp.85-97
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    • 2019
  • Today, building constructions are becoming larger, higher, deeper, and complex to improve quality of human life and meet various needs. As a result, new design space for non - typically standardized space has been created, and targets for performance-based design are also becoming increased. An evacuation safety evaluation of performance-based design should be compared with ASET and RSET estimation so that the value of RSET does not exceed the value of ASET. However, there is a problem that it is difficult to secure the safety with using the performance-based design evaluation method currently in use, especially in case of the underground parking lot, because it has wide compartment area and various routes for evacuation. Therefore, in order to overcome these problems, this paper first investigates the simulation setting method of the performance-based design that is currently in use, and then conducts two fire simulations and three evacuation simulations for underground parking lots each time, so performs the evacuation safety evaluationin total six cases of situations. Here this paper analyzes the problem with comparative evaluation research and suggests the better solution for improved evacuation safety evaluation of performance-based design.

A Study on the Material Characteristics of Stone Tools Excavated from the Remain Point of Paleolithic Age in Osong Site, Cheongju

  • Kim, Jae Hwan;Han, Min Su
    • Journal of Conservation Science
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    • v.35 no.1
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    • pp.41-49
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    • 2019
  • This study analyzes the material characteristics of stone tools of the Paleolithic period excavated from the Osong site, located at the project site for the creation of the Osong 2nd Life Science Complex, and estimates the provenance of the stone materials. Because the stones had been buried for a long time, their surfaces had become heavily weathered yellow or yellowish-brown, and the magnetic susceptibility values varied from 0 to 15(${\times}10^{-3}SI$). The excavated stone tools were rocks with various magnetic susceptibility values that could not be specified. Five stone tools subjected to destructive analysis were divided into two groups, one with a value of 1-3(${\times}10^{-3}SI$) and the other with a value of 5-9(${\times}10^{-3}SI$), both based on visible characteristics. The results of the thin-section analysis showed that most of the stone tools were basaltic rocks comprising plagioclase, quartz, and pyroxene, and some had iron content as high as 20 wt.%. These findings and the present geological map suggest that the stone tools were not made from the surrounding rocks because there are no areas containing basaltic rocks surrounding Bongsan-ri in Osong-eup. Andesite and tuff are distributed along with basaltic rocks in the Doan-myeon area in Jeongpyeong-gun, Chungcheongbuk-do Province, but the distance from the excavation site is too far. To determine whether this region is actually related to the provenance of the raw rock, it is necessary to conduct additional field surveys and comprehensive and precise analyses.

Development and Validation of Generalized Linear Regression Models to Predict Vessel Enhancement on Coronary CT Angiography

  • Masuda, Takanori;Nakaura, Takeshi;Funama, Yoshinori;Sato, Tomoyasu;Higaki, Toru;Kiguchi, Masao;Matsumoto, Yoriaki;Yamashita, Yukari;Imada, Naoyuki;Awai, Kazuo
    • Korean Journal of Radiology
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    • v.19 no.6
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    • pp.1021-1030
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    • 2018
  • Objective: We evaluated the effect of various patient characteristics and time-density curve (TDC)-factors on the test bolus-affected vessel enhancement on coronary computed tomography angiography (CCTA). We also assessed the value of generalized linear regression models (GLMs) for predicting enhancement on CCTA. Materials and Methods: We performed univariate and multivariate regression analysis to evaluate the effect of patient characteristics and to compare contrast enhancement per gram of iodine on test bolus (${\Delta}HUTEST$) and CCTA (${\Delta}HUCCTA$). We developed GLMs to predict ${\Delta}HUCCTA$. GLMs including independent variables were validated with 6-fold cross-validation using the correlation coefficient and Bland-Altman analysis. Results: In multivariate analysis, only total body weight (TBW) and ${\Delta}HUTEST$ maintained their independent predictive value (p < 0.001). In validation analysis, the highest correlation coefficient between ${\Delta}HUCCTA$ and the prediction values was seen in the GLM (r = 0.75), followed by TDC (r = 0.69) and TBW (r = 0.62). The lowest Bland-Altman limit of agreement was observed with GLM-3 (mean difference, $-0.0{\pm}5.1$ Hounsfield units/grams of iodine [HU/gI]; 95% confidence interval [CI], -10.1, 10.1), followed by ${\Delta}HUCCTA$ ($-0.0{\pm}5.9HU/gI$; 95% CI, -11.9, 11.9) and TBW ($1.1{\pm}6.2HU/gI$; 95% CI, -11.2, 13.4). Conclusion: We demonstrated that the patient's TBW and ${\Delta}HUTEST$ significantly affected contrast enhancement on CCTA images and that the combined use of clinical information and test bolus results is useful for predicting aortic enhancement.

Implications of the Increase of Single Person Households for High-Tech Industries: Focusing on AI Adopted Products (1인 가구 증가가 하이테크 산업에서 지니는 함의: 인공지능기술 탑재 상품을 중심으로)

  • Cho, Jae-Yung
    • Journal of Convergence for Information Technology
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    • v.9 no.6
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    • pp.146-152
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    • 2019
  • This study discussed implications of the increase of single person households (SH) for high-tech industries especially focusing on artificial intelligence (AI) adopted products, based on critically reviewing the past researches on their characteristics including consumption trends; the improvement of AI technology; and its market potentiality in various industries. According to the results, SH spent more time with others like friends and neighbors more than couples. Younger people increasingly chose to live alone by their own free will for achieving their goals. 'Living alone' or 'going solo' is not thought negatively any more, but as a new market power in the future. Considering their value oriented consumption behaviors based on spirit of independence and individualism, they will need high-tech products more like AI adopted products than others because of their advantages for the value of single life. Thus, the rapid progress of AI technology is predicted to bring them satisfaction of their wants and it is suggested to prepare for the market segmentation of SH as AI end-users.

A Study on Smart Fitness Models for Active Senior (액티브시니어를 위한 스마트 피트니스 모델에 관한 연구)

  • Seungae Kang
    • Convergence Security Journal
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    • v.22 no.1
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    • pp.135-140
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    • 2022
  • This study aims to analyze exercise cases and issues using smart devices and technologies, and to present the development direction of a smart exercise environment suitable for the wellness life of active seniors with high activity and economic power unlike the existing silver generation. In the fitness industry, the subscription economy that regularly receives or uses necessary exercise tools, services, and digital content is expanding, and business models based on hardware sales and content subscription continue to emerge. In order to have value competitiveness as a platform that provides active seniors with integrated exercise services for health care, not only fitness centers, but also home training exercise equipment, fitness-related applications, and smart wearable device markets should be organically connected to form an expanded total platform. In order to have value competitiveness as a platform that provides active seniors with integrated exercise services for health care, not only fitness centers, but also home training exercise equipment, fitness-related applications, and smart wearable device markets should be organically connected to form an expanded total platform. The linkage of the digital healthcare function, which provides real-time changes to exercise programs based on continuous monitoring and feed back through wearable devices before, after, and during exercise by receiving and selecting exercise programs suitable for individual health status, is the differentiating factor in the smart fitness model.

A Study of Development of Change Process for Configuration Management in Construction Project Management (건설사업관리에서 형상관리에 관한 변경 프로세스 개선에 관한 연구)

  • Ko, Ho-Un;Park, Hyung-Keun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.1D
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    • pp.81-89
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    • 2009
  • CM(Configuration Management) is a field of management that focuses on establishing and maintaining consistency of a product's performance and its functional and physical attributes with its requirements, design, and operational information throughout its life. Recently upcoming concept of CM, regardless of various definitions, consists of the organization and the process for value creation through project change management, value preservation by Risk, Project Management implementation by Change management. The CM provide a basis for, and a record of, the project's performance in meeting the scope, time, cost. Overseas international companies have already adopted the CM system and enjoyed the benefits arising from such systems. And the CM provides perspectives and insights applicable to all types of projects. This study presents the review on the current systems now in use at jobsites and known to be efficient, and the introduction and application of configuration systems now at big issue. Hereby indicates the connective system consisted of work process, change control and knowledge referring to the methods and actual cases as an effective promotion of CM.

Pharmacokinetics of oxytetracycline in hybrid catfish (Clarias macrocephalus x C. gariepinus) after intravascular and oral administrations

  • Amnart Poapolathep;Kednapat Sriphairoj;Sittichai Hatachote;Kannika Wongpanit;Duangkamol Saensawath;Narumol Klangkaew;Napasorn Phaochoosak;Mario Giorgi;Saranya Poapolathep
    • Journal of Veterinary Science
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    • v.25 no.4
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    • pp.58.1-58.8
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    • 2024
  • Importance: Over the past decade, catfish farming has increased in Southeast Asia. However, there has been no existing for pharmacokinetic data in the hybrid catfish (Clarias macrocephalus x C. gariepinus). Objective: This study was designed to evaluate the pharmacokinetic characteristics of oxytetracycline (OTC) in the hybrid catfish, following single intravascular (IV) or oral (PO) administration at a single dosage of 50 mg/kg body weight (BW). Methods: In total, 140 catfish (each about 100-120 g BW) were divided into two groups (n = 70). Blood samples (0.6-0.8 mL) were collected from ventral caudal vein at pre-assigned times up to 144 h (sparse samples design). OTC plasma concentrations were analyzed using high-performance liquid chromatography-photodiode array detector. Results: The pharmacokinetic parameter of OTC was evaluated using a non-compartment model. OTC plasma concentrations were detectable for up to 144 and 120 h after IV and PO, respectively. The elimination half-life value of OTC was long with slow clearance after IV administration in hybrid catfish. The average maximum concentration value of OTC was 2.72 ㎍/mL with a time at the maximum concentration of 8 h. The absolute PO bioavailability was low (2.47%). Conclusions and Relevance: These results showed that PO administration of OTC at a dosage of 50 mg/kg BW was unlikely to be effective for clinical use in catfish. The pharmacodynamic properties and clinical efficacy of OTC after multiple medicated feed are warranted.

Establishment of a quality index of surfactin production during cheonggukjang fermentation (청국장 발효 중 surfactin 생산량 품질지표 설정)

  • Chang-Geun Ji;Jeong-Hwa Hong;Sang-Hyun Lee
    • Food Science and Preservation
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    • v.30 no.2
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    • pp.311-320
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    • 2023
  • Surfactin, one of the most powerful biosurfactants, can be widely applied in agriculture, food, and pharmaceutics. The purpose of the present study was to establish suitable indicators for a rapid detection method that can confirm the surfactin productivity of cheonggukjang. In the present study, changes in the total number of bacteria were quantified according to the fermentation time of chenggukjang. Furthermore, physicochemical factors, such as pH, color value, surface tension, refractive index, absorbance, and protein contents, were assessed in chenggukjang viscous substances, and a correlation analysis between the physicochemical factors and surfactin contents was performed. We found that the protein contents gradually increased up to 48 h (4.21±0.11 mg/mL) without a change in the surface tension. Furthermore, the refractive index, absorbance at 280 nm, and color value were significantly increased as the fermentation time increased; however, there were no statistically significant differences after 36 h of fermentation. Interestingly, this result exhibited a tendency similar to the surfactin content according to fermentation time. These findings suggest that surfactin can be used as a suitable quality indicator and may provide an experimental basis for the fermented food industry.

Reliability-Based Service Life Estimation of Concrete in Marine Environment (신뢰성이론에 기반한 해양환경 콘크리트의 내구수명 평가)

  • Kim, Ki-Hyun;Cha, Soo-Won
    • Journal of the Korea Concrete Institute
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    • v.22 no.4
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    • pp.595-603
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    • 2010
  • Monte-Carlo simulation technique is often used in order to predict service life of concrete structure subjected to chloride penetration in marine environment based on probability theory. Monte-Carlo simulation method, however, the method gives different results every time that the simulation is run. On the other hand, moment method, which is frequently used in reliability analysis, needs negligible computational cost compared with simulation technique and gives a constant result for the same problem. Thus, in this study, moment method was applied to the calculation of corrosion-initiation probability. For this purpose, computer programs to calculate failure probabilities are developed using first-order second moment (FOSM) and second-order second moment (SOSM) methods, respectively. From the analysis examples with the developed programs, SOSM was found to give a more accurate result than FOSM does. The sensitivity analysis has shown that the factor affecting the corrosion-initiation probability the most was the cover depth, and the corrosion-initiation probability was influenced more by its coefficient of variation than its mean value.

Comparison of the Chemotaxis Potential of Bacteria Isolated from Spinach Roots and Nonrhizosphere Soil

  • Kim, Jong-Shik;Sakai Masao;Lee, Si-Kyung;Yahng, Chahng-Sook;Matsuguchi Tatsuhiko
    • Journal of Microbiology and Biotechnology
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    • v.11 no.1
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    • pp.160-163
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    • 2001
  • In order to investigate the role of bacterial chemotaxis in root colonization, the chemotaxis potential of bacteria isolated from spinach roots was compared with that of bacteria from nonhizosphere soil, with reference to the plant age (1,000 isolates), soil moisture conditons (1,400 isolates), and part of the root (200 isolates). The % CT (% occurrence of chemotaxis (+) isolates among total bacterial isoltes) of the root isolates significantlyfluctuated during the plant growth period, reaching a maximum after 10-15 days of growth. At this time period, the maximum % CT for the root isolates was around 70-80% CT under a soil moisture 50% WFP (% volume of water-filled pores in total soil pores), and then gradually reduced with an increasing % WFP. The results of the chemotaxis potential of each of the 100 islates from the spinach roots and nonrhizosphere soil under various % WFP demonstrated that the % CT of the root isolates were significantly higher than those of solates from the nonrhizosphere soil under a wide range of soil moisture content (35-80% WFP). Furthermore, the % CT value (80%) from the upper root was significantly higher than tht (55%) from the lower root. Compared with the % CT values of the roots, the values from the nonrhizosphere soil did not significantly vary relative to the plant age of % WFP. These results indicate that chemotaxis would appear to be a major factor in bacterial root colonization.

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