• Title/Summary/Keyword: Performance design method

Search Result 8,711, Processing Time 0.042 seconds

An Experimental Study on the Charring Rate of Solid Sawn Timber Exposed to Fire (화재에 노출된 제재목의 탄화속도에 대한 실험적 연구)

  • Yeo, In-Hwan;Park, Kyung-Hoon;Cho, Kyung-Suk;Min, Byung-Yeol;Yoon, Myung-O
    • Fire Science and Engineering
    • /
    • v.25 no.3
    • /
    • pp.78-84
    • /
    • 2011
  • In this study, we have measured the charring rate of solid sawn timber as a preceding step for develop performance based fire safety design method of wood framed building structures. The follows are the summary of fire test results carried out with $400{\times}400$ mm cross-section Douglas-fir in varied of thickness and grain directions. I) When the timber thickness increase under same dimension, the charring rate decreases gradually. It is seemed the charring layer up on a thickness roles as a insulation, gives combustion delaying time to specimen. 2) The charring rates measured at different depths (10, 20, 30, 40 mm) in timber which varying thickness (20, 40, 80, 120 mm) when exposed maximum 1 hour standard fire increase by 30 mm depth, but decrease at 40 mm. It is seemed the minimum charr layer should be 30 mm for having role of insulation. 3) The charring rate of cross section surface (direction of perpendicular to grain) was more high than that of grain direction. It can be explained by the cracks and gaps from greater charr contraction made more heat flux incident into timber.

Optimal Cultivation Time for Yeast and Lactic Acid Bacteria in Fermented Milk and Effects of Fermented Soybean Meal on Rumen Degradability Using Nylon Bag Technique

  • Polyorach, S.;Poungchompu, O.;Wanapat, M.;Kang, S.;Cherdthong, A.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.29 no.9
    • /
    • pp.1273-1279
    • /
    • 2016
  • The objectives of this study were to determine an optimal cultivation time for populations of yeast and lactic acid bacteria (LAB) co-cultured in fermented milk and effects of soybean meal fermented milk (SBMFM) supplementation on rumen degradability in beef cattle using nylon bag technique. The study on an optimal cultivation time for yeast and LAB growth in fermented milk was determined at 0, 4, 8, 24, 48, 72, and 96 h post-cultivation. After fermenting for 4 days, an optimal cultivation time of yeast and LAB in fermented milk was selected and used for making the SBMFM product to study nylon bag technique. Two ruminal fistulated beef cattle ($410{\pm}10kg$) were used to study on the effect of SBMFM supplementation (0%, 3%, and 5% of total concentrate substrate) on rumen degradability using in situ method at incubation times of 0, 2, 4, 6, 12, 24, 48, and 72 h according to a Completely randomized design. The results revealed that the highest yeast and LAB population culture in fermented milk was found at 72 h-post cultivation. From in situ study, the soluble fractions at time zero (a), potential degradability (a+b) and effective degradability of dry matter (EDDM) linearly (p<0.01) increased with the increasing supplemental levels and the highest was in the 5% SBMFM supplemented group. However, there was no effect of SBMFM supplement on insoluble degradability fractions (b) and rate of degradation (c). In conclusion, the optimal fermented time for fermented milk with yeast and LAB was at 72 h-post cultivation and supplementation of SBMFM at 5% of total concentrate substrate could improve rumen degradability of beef cattle. However, further research on effect of SBMFM on rumen ecology and production performance in meat and milk should be conducted using in vivo both digestion and feeding trials.

Application of ultrasonic energy to enhance capability of soil improving material (지반보강용 주입재의 성능향상을 위한 초음파 에너지의 활용)

  • Moon, Jun-ho;Xin, Zhenhua;Jeong, Ghang-bok;Kim, Young-uk
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.19 no.4
    • /
    • pp.567-576
    • /
    • 2017
  • In a performance-based design, the structural safety is estimated from pre- defined damage states and corresponding damage indices. Both damage states and damage indices are well defined for above-ground structures, but very limited studies have been performed on underground structures. In this study, we define the damage states and damage indices of a cut-and-cover box tunnel which is one of typical structures used in metro systems, under a seismic excitation from a series of inelastic frame analyses. Three damage states are defined in terms of the number of plastic hinges that develop within the structure. The damage index is defined as the ratio of the elastic moment to the yield moment. Through use of the proposed index, the inelastic behavior and failure mechanism of box tunnels can be simulated and predicted through elastic analysis. In addition, the damage indices are linked to free-field shear strains. Because the free-field shear strain can be easily calculated from a 1D site response analysis, the proposed method can be readily used in practice. Further studies are needed to determine the range of shear strains and associated uncertainties for various types of tunnels and site profiles. However, the inter-linked platform of damage state - damage index - shear wave velocity - shear strain provides a novel approach for estimating the inelastic response of tunnels, and can be widely used in practice for seismic designs.

A Study on the Turnover Intention of Salespeople in Insurance Distribution Channels (보험유통채널에서 영업사원의 이직의도에 관한 연구)

  • Ryu, Gayeon;Kim, Dong-Hyun;Cha, Jae-Bin
    • Journal of Distribution Science
    • /
    • v.16 no.7
    • /
    • pp.77-86
    • /
    • 2018
  • Purpose - In the insurance distribution channel, the salespeople plays a role of representing the company, and recognizes the needs of the customers and plays a role in responding to them. Therefore, their turnover can have a great influence on the company performance. The purpose of this study is to investigate the structural relationship between salespeople's personal - environmental fit and organizational commitment and turnover intention. Research design, data, and methodology - Data collection was conducted a self-filling questionnaire for salespeople for about one month from July 24, 2017 to August 30, 2017. The subjects of the questionnaire were the insurance salespeople who work in the sales line such as K life, S fire. A total of 450 copies were distributed and 432 copies of the questionnaire were used for final analysis. The analysis program used SPSS 22.0 and AMOS 22.0 programs. Analysis method was Frequency Analysis, Reliability & Confirmatory Factor Analysis, Correlation Analysis and Structural Equation Model(SEM). Results - As a result of Hypothesis 1, Person-Supervisor Fit had significant influence only on Continuance Commitment. Person-Job Fit did not have a significant effect on Organizational Commitment. Person-Coworker Fit had a significant effect on Continuance Commitment and Affective Commitment. Person-Organization Fit had a significant impact on Affective Commitment. Therefore, only , , , , were adopted. As a result of Hypothesis 2, Continuance Commitment had a significant effect on turnover intention. Therefore, only was adopted. Conclusions - This study suggests that it is necessary to manage the human resources in the sales field through studies related to salespeople's extension of the research scope and salespeople's turnover intention. Based on the results of this study, the conclusion suggests some implications for the efficient human resources management of insurance companies in sales channels. It is expected that it will be helpful for the salespeople to find out what kind of Person-Environment Fit affects the organizational commitment and how to manage the organizational commitment among the three dimensions of organizational commitment to reduce turnover intention.

Effects of Feeding Patterns and Sexes on Growth Rate, Carcass Trait and Grade in Korean Native Cattle

  • Choi, B.H.;Ahn, B.J.;Kook, K.;Sun, S.S.;Myung, K.H.;Moon, S.J.;Kim, J.H.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.15 no.6
    • /
    • pp.838-843
    • /
    • 2002
  • The objectives of this study were to examine growth performance and meat quality by three different feeding patterns in Korean native cattle (KNC). In each of 3 years, fifteen KNC were randomly assigned in a (3 feeding management)${\times}$(3 sex) factorial design experiment; thus, in total, there were 5 animals in each of the 9 treatments. The three feeding management treatments were longterm (24 month) restriction feeding (LTFR), long-term restriction feeding-hormone implant (LTFR-tH), and short-term (18 month) nonrestriction feeding (STFNR). Three sexes were bull, steer, and heifer. Concentrate diet was fed restriction-feeding method based on body weight in LTFR and LTFR-tH. However, the diet was fed ad libitum in STFNR. Hormonal implantation was made three times with M-$PO^{TM}$ for bulls and with F-$TO^{TM}$ for heifers at 18, 20, 22 month of age in LTFR-tH. Animal were purchased from the local cattle market and managed in two local farms and at the university research unit. Animals were slaughtered at 24 months for long-term trial and at 18 month for short-term trial. The growth rate was the highest in bulls and the lowest in heifers. However, the differences were diminished in F-$TO^{TM}$ implanted heifers. The average daily gain was high in STFNR due to ad libitum feeding. The carcass grade was similar among the treatments on percentage bases. Hormonal implants improved significantly the meat quality grade in all sexes. Castration increased body fat content and improved meat quality grade by intramuscular fat deposition. In conclusion, long-term feeding and hormone treatment increased meat quality grade more than short-term feeding. However, ADG was higher in the short-term trial although feedefficiency was lower.

A Study on Design of Reference Stations and Integrity Monitors for Maritime DGPS Recapitalization (해양용 DGPS 구조개선을 위한 RSIM 설계에 관한 연구)

  • Park, Sang-Hyun;Seo, Ki-Yeol;Cho, Deuk-Jae;Suh, Sang-Hyun
    • Journal of Navigation and Port Research
    • /
    • v.33 no.10
    • /
    • pp.691-697
    • /
    • 2009
  • Hardware dedicated off-the-shelf maritime differential GPS RSIM lacks the open architecture to meet all the minimum maritime user requirements and to include future GNSS improvements after recapitalization. This paper carries out a study to replace existing hardware dedicated differential GPS RSIM with software differential GPS RSIM in order to make up the weak point of hardware dedicated off-the-shelf maritime differential GPS RSIM. In this paper, the architecture of software RSIM is proposed for maritime DGPS recapitalization. And the feasibility analysis of the proposed software differential GPS RSIM is performed as the first phase to realize the proposed architecture. For the feasibility analysis, the prototype RF module and DSP module are implemented with properties as wide RF bandwidth, high sampling frequency, and high speed transmission interface. This paper shows that the proposed architecture has the possibility of real time operation of software RSIM functionality onto the PC-based platform through the analysis of computation time. Finally, this paper verifies that the L1/L2 dual frequency software differential RSIM designed according to the proposed method satisfies the performance specifications set out in RTCM paper 221-2006-SC104-STD.

An Improvement of Implementation Method for Multi-Layer AHB BusMatrix (ML-AHB 버스 매트릭스 구현 방법의 개선)

  • Hwang Soo-Yun;Jhang Kyoung-Sun
    • Journal of KIISE:Computer Systems and Theory
    • /
    • v.32 no.11_12
    • /
    • pp.629-638
    • /
    • 2005
  • In the System on a Chip design, the on chip bus is one of the critical factors that decides the overall system performance. Especially, in the case or reusing the IPs such as processors, DSPs and multimedia IPs that requires higher bandwidth, the bandwidth problems of on chip bus are getting more serious. Recently ARM proposes the Multi-Layer AHB BusMatrix that is a highly efficient on chip bus to solve the bandwidth problems. The Multi-Layer AHB BusMatrix allows parallel access paths between multiple masters and slaves in a system. This is achieved by using a more complex interconnection matrix and gives the benefit of increased overall bus bandwidth, and a more flexible system architecture. However, there is one clock cycle delay for each master in existing Multi-Layer AHB BusMatrix whenever the master starts new transactions or changes the slave layers because of the Input Stage and arbitration logic realized with Moore type. In this paper, we improved the existing Multi-Layer AHB BusMatrix architecture to solve the one clock cycle delay problems and to reduce the area overhead of the Input Stage. With the elimination of the Input Stage and some restrictions on the arbitration scheme, we tan take away the one clock cycle delay and reduce the area overhead. Experimental results show that the end time of total bus transaction and the average latency time of improved Multi-Layer AHB BusMatrix are improved by $20\%\;and\;24\%$ respectively. in ease of executing a number of transactions by 4-beat incrementing burst type. Besides the total area and the clock period are reduced by $22\%\;and\;29\%$ respectively, compared with existing Multi-layer AHB BusMatrix.

Numerical Study on Shotcrete Lining with Steel Reinforcement Using a Fiber Section Element (화이버 단면 요소를 이용한 강재 보강된 숏크리트 라이닝의 수치해석적 연구)

  • Kim, Jeong Soo;Yu, Jee Hwan;Kim, Moon Kyum
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.34 no.3
    • /
    • pp.919-930
    • /
    • 2014
  • In this study, the load capacities and behaviors of a shotcrete member with steel supports, as composite member, are investigated numerically by using a fiber section element. The cross section of a shotcrete lining with steel support is divided into a bundle of fibers, which are allocated nonlinear stress-strain relations and used for determining internal forces. To verify the used approach of the finite element method for shotcrete with steel supports, the load-displacement relations of shotcrete lining obtained by numerical analysis are compared with existing experimental results and are analyzed with the stress distribution of the shotcrete and steel support obtained numerically. As a result, it is shown that the proposed approach can predict the load capacities of each material and the overall nonlinear behavior of shotcrete lining with steel supports. The change of location of the neutral axis and the flexural resistance ratio of each material are also derived from the stress distribution of the cross section of the shotcrete lining with steel supports. From the results, it is concluded that the flexural resistance performance of steel support should be considered in shotcrete lining design.

A Bayesian Approach to Gumbel Mixture Distribution for the Estimation of Parameter and its use to the Rainfall Frequency Analysis (Bayesian 기법을 이용한 혼합 Gumbel 분포 매개변수 추정 및 강우빈도해석 기법 개발)

  • Choi, Hong-Geun;Uranchimeg, Sumiya;Kim, Yong-Tak;Kwon, Hyun-Han
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.38 no.2
    • /
    • pp.249-259
    • /
    • 2018
  • More than half of annual rainfall occurs in summer season in Korea due to its climate condition and geographical location. A frequency analysis is mostly adopted for designing hydraulic structure under the such concentrated rainfall condition. Among the various distributions, univariate Gumbel distribution has been routinely used for rainfall frequency analysis in Korea. However, the distributional changes in extreme rainfall have been globally observed including Korea. More specifically, the univariate Gumbel distribution based rainfall frequency analysis is often fail to describe multimodal behaviors which are mainly influenced by distinct climate conditions during the wet season. In this context, we purposed a Gumbel mixture distribution based rainfall frequency analysis with a Bayesian framework, and further the results were compared to that of the univariate. It was found that the proposed model showed better performance in describing underlying distributions, leading to the lower Bayesian information criterion (BIC) values. The mixed Gumbel distribution was more robust for describing the upper tail of the distribution which playes a crucial role in estimating more reliable estimates of design rainfall uncertainty occurred by peak of upper tail than single Gumbel distribution. Therefore, it can be concluded that the mixed Gumbel distribution is more compatible for extreme frequency analysis rainfall data with two or more peaks on its distribution.

A Study on the Development and Measurement of Logistics Partners Cooperation Index(LPCI): Focused on the Joint Logistics (물류협력지수의 개발 및 측정에 관한 연구: 공동물류사업을 중심으로)

  • Suh, Sang-Sok;Song, Gwang-Suk;Park, Jong-Woo
    • Journal of Distribution Science
    • /
    • v.14 no.6
    • /
    • pp.107-118
    • /
    • 2016
  • Purpose - Over 90% of Domestic logistics industry is small enterprise and they are experiencing growth stagnation due to price-based competition structure rather than constructing logistics service of high added value. In order to get over this situation and pursue the development of logistics industry, strengthening its competitiveness, through inter-enterprise cooperative network build-up, would be a key alternative. Therefore, in this study, an index for measuring inter-enterprise cooperation level of Joint logistics business will be developed as a typical collaborative business model in logistics industry. Moreover, a strengthening competitiveness method suggests a developmental step and a key management index to mature in logistics industry. Research Design, Data, Methodology - This study is an index development research for measuring inter-enterprise cooperation level of logistics industry. Such a level was measured by performing a survey by targeting enterprises that participated in Joint logistics business. The targeting enterprises are typical cooperative models in logistics industry. Measurement items were developed which were based on the presented items in existing research. Question items were composed of selection type questions as answering Yes/No. They measures implementation status of corporate activity and detailed activity items measuring qualitative level. Total samples were based on 116 enterprise samples including 90 logistics enterprises and 26 shippers. In addition, by evaluating the importance for Joint logistics business recognition with personnel working level, the weight of measuring variable was extracted. This study has built an assessment tools (LPCI) on Joint logistics business cooperation level in a situation where there are no previous studies on joint logistics business, this study is meaningful for other studies. Results - As a result of analyzing LPCI presented in this study, the score of logistics enterprise was represented as 59.9 points based on full score of 100 points and that of shippers as 47.2 points and cooperation level among enterprises participated in Joint logistics business was revealed to be very low. In particular, as a result of measuring the importance between logistics enterprise and shippers, the difference by each measurement standard was represented among those enterprises. This difference is considered to be a key factor that cooperative operational conformity between logistics enterprises and shippers is represented to be low. Conclusions - As most joint logistics business, being promoted at present, is sharing facility and information with joint logistics business, it is hard to find such a joint logistics business in reality based on cooperative business model in main cooperation agents. Therefore, competitiveness of logistics industry could be strengthened by promoting joint logistics business based on their mutual cooperation among enterprises. In other words, it is to secure sustainable competitiveness of joint logistics business together with creation of new market by inter-enterprise cooperation based on integration of basic logistics business.