• Title/Summary/Keyword: Scale-model

Search Result 8,304, Processing Time 0.042 seconds

The Study for Process Capability Analysis of Software Failure Interval Time (소프트웨어 고장 간격 시간에 대한 공정능력분석에 관한 연구)

  • Kim, Hee-Cheul;Shin, Hyun-Cheul
    • Convergence Security Journal
    • /
    • v.7 no.2
    • /
    • pp.49-55
    • /
    • 2007
  • Software failure time presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing. For data analysis of software reliability model, data scale tools of trend analysis are developed. The methods of trend analysis are arithmetic mean test and Laplace trend test. Trend analysis only offer information of outline content. From the subdivision of this analysis, new attemp needs the side of the quality control. In this paper, we discuss process capability analysis using process capability indexs. Because of software failure interval time is pattern of nonnegative value, instead of capability analysis of suppose to normal distribution, capability analysis of process distribution using to Box-Cox transformation is attermpted. The used software failure time data for capability analysis of process is SS3, the result of analysis listed on this chapter 4 and 5. The practical use is presented.

  • PDF

A Study for Locating of a New Store Considering Competition for Trading Area: Focusing on the Case of Hypermarket in Seoul Metropolitan Area (상권경쟁을 고려한 신규점포의 입지선정에 관한 연구 - 서울시 대형마트를 대상으로 -)

  • Tae, Kyoung-Soub;Rhim, Byeong-Jun
    • Journal of the Korean Geographical Society
    • /
    • v.45 no.5
    • /
    • pp.609-627
    • /
    • 2010
  • Finding the ideal location for your business is one of the most critical and important steps you will have to undertake. Otherwise, done in the wrong way you will only end up paying an expensive cost for an unsuitable location. Therefore to select the perfect location for your business, this study makes a reasonable and simple model for retail shops by calculating occupation population for each store applying Huffs "Probability Theory" to Hypermarket in Seoul. Then this study, based on occupation population, has divided every unit section (dong scale) into 4 market types which represent the state of the competitive markets, including monopoly, oligopoly, competitive, and noncompetitive markets. Consequently, the most reasonable place to locate a new store is where it can take most of the customers, that is, a place which can take non-competitive market as much as possible and is distant far enough from competitive market where competition is severe.

Safety Evaluation of a Radioisotope Transport Package (방사성 동위원소 운반용기의 안전성 평가)

  • Lee, J.C.;Ku, J.H.;Seo, K.S.;Min, D.K.
    • Journal of Radiation Protection and Research
    • /
    • v.22 no.4
    • /
    • pp.251-261
    • /
    • 1997
  • A package to transport the high level radioactive materials is required to withstand the hypothetical accident conditions as well as normal transport conditions according to IAEA standards and domestic regulations. The regulations require that the package should maintain the shielding, thermal and structural integrities to release no radioactive material. In general, safety evaluation of packages is performed by experimental methods using scale model and/or analytical methods using computer codes. This paper presents the safety evaluation of package to transport the radioisotopes produced in the HANARO to the radioisotope production facility. Radiation shielding, thermal and structural analyses were peformed using the computer codes. It has been verified that the package is safe under hypothetical accident conditions as well as normal transport conditions.

  • PDF

Effects of Job Stress and Supervisory Support on Depression of Care Givers in Elderly Care Facilities (직무 스트레스와 직장 상사의 지지가 요양보호사의 우울감 경험에 미치는 영향)

  • Hwang, Ju Hee;Choi, Sungyeau;Park, Hyunju
    • Korean Journal of Occupational Health Nursing
    • /
    • v.24 no.4
    • /
    • pp.352-362
    • /
    • 2015
  • Purpose: The purpose of this study was to investigate the effects of job stress and support from supervisors on depression of care givers in elderly care facilities. Methods: Subjects were 191 care givers working in elderly care facilities in K-Province in Korea. Data were collected from self-administered questionnaires. Descriptive statistics, ${\chi}^2$ test, t-test, F-test, Pearson's and Spearman's correlation coefficients, and hierarchical multiple logistic regression with dummy variables were used for statistical analysis of data. Results: Job stress measured with Korean Occupational Stress Scale was $56.16{\pm}5.88$. Emotional and instrumental support from supervisors were $37.05{\pm}7.30$ and $32.39{\pm}7.34$, respectively. After controlling for general characteristics, job stress was significantly related to depression (OR: 1.07, 95% CI: 1.01~1.14). However, job stress became non-significant in the model that included instrumental support from supervisors. Not emotional but instrumental support from supervisors was significantly related to depression of care givers (OR: 0.93, 95% CI: 0.88~0.99). Conclusion: Results of this study suggest that job stress has negative effects and instrumental support from supervisors has protective effects on depression of care givers in elderly care facilities. Therefore, measures to increase instrumental support by supervisors should be developed to improve psychological health of care givers in elderly care facilities.

Three-Dimensional Numerical Magnetohydrodynamic Simulations of Magnetic Reconnection in the Interstellar Medium

  • TANUMA SYUNITI;YOKOYAMA TAKAAKI;KUDOH TAKAHIRO;SHIBATA KAZUNARI
    • Journal of The Korean Astronomical Society
    • /
    • v.34 no.4
    • /
    • pp.309-311
    • /
    • 2001
  • Strong thermal X-ray emission, called Galactic Ridge X-ray Emission, is observed along the Galactic plane (Koyama et al. 1986). The origin of hot ($\~$7 keV) component of GRXE is not known, while cool ($\~$0.8 keV) one is associated with supernovae (Kaneda et al. 1997, Sugizaki et al. 2001). We propose a possible mechanism to explain the origin; locally strong magnetic fields of $B_{local}\;\~30{\mu}G$ heat interstellar gas to $\~$7 keV via magnetic reconnection (Tanuma et al. 1999). There will be the small-scale (< 10 pc) strong magnetic fields, which can be observed as $(B)_{obs} \;\~3{\mu}G$ by integration of Faraday Rotation Measure, if it is localized by a volume filling factor of f $\~$ 0.1. In order to examine this model, we solved three-dimensional (3D) resistive magnetohydrodynamic (MHD) equations numerically to examine the magnetic reconnect ion triggered by a supernova shock (fig.l). We assume that the magnetic field is Bx = 30tanh(y/20pc) $\mu$G, By = Bz = 0, and the temperature is uniform, at the initial condition. We put a supernova explosion outside the current sheet. The supernova-shock, as a result, triggers the magnetic reconnect ion, and the gas is heatd to > 7 keV. The magnetic reconnect ion heats the interstellar gas to $\~$7 keV in the Galactic plane, if it occurs in the locally strong magnetic fields of $B_{local}\;\~30{\mu}G$. The heated plasma is confined by the magnetic field for $\~10^{5.5} yr$. The required interval of the magnetic reconnect ions (triggered by anything) is $\~$1 - 10 yr. The magnetic reconnect ion will explain the origin of X-rays from the Galactic ridge, furthermore the Galactic halo, and clusters of galaxies.

  • PDF

Design of QoS-based Routing Algorithm for Internet Services on Large Scale ATM Networks (광역 ATM 망 적용을 위한 QoS 보장형 라우팅 알고리즘 설계)

  • 손승원;장종수;정연서;오창석
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.24 no.10A
    • /
    • pp.1517-1531
    • /
    • 1999
  • The Internet is recently evolving into the directions which is capable of incorporating stream-type services such as voice and video services. However, the existing Internet can only support a best-effort delivery model and thus it is difficult to satisfy these requirements as well as to provide the QoS beyond a certain degree. Accordingly, it is imperative to develop QoS based routing algorithm in order to allow the routing by the user's QoS demand and to be applied into wide area networks. In this thesis, we presented new routing algorithms and made performance evaluations. The proposed algorithms allow the routing by the user’s QoS demand level in order to provide the diverse Internet application services based on ATM network environment that is expected to play a role as an infrastructure of high-speed communication network. They also have a feature of shortening the waiting time for address analysis and have a quality-proven characteristics with enhanced network scalability.

  • PDF

Performance Analysis and Design of Multiservice Network for Constant- and Adaptive-rate Services (고정 전송율 및 가변 전송율 서비스를 지원하는 다중 서비스 네트워크의 성능 분석 및 설계)

  • 이태진
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.26 no.11C
    • /
    • pp.33-42
    • /
    • 2001
  • We consider a model describing large scale performance of multiservice networks supporting both constant- and adaptive-rate services. As the number of constant-rate connection changes over time in multiservice networks, the available bandwidth for adaptive-rate connections changes as well. We estimate the available bandwidth for adaptive-rate service in a dynamically changing traffic environment based on Erlang fixed point equation and Little\`s law. The bandwidth allocation for adaptive-rate service is determined by the max-min fairness criterion. We find an upper bound on the average minimum throughput for adaptive-rate service, and 7how that the bound is achieved in large-capacity networks. This is verified using network examples. Since max-min fair allocation may not maximize the total throughput or revenue in a network, we consider adjustments via network level priority schemes to increase efficiency.

  • PDF

Clinical results of conservative management in patients with full-thickness rotator cuff tear: a meta-analysis

  • Karasuyama, Masaki;Gotoh, Masafumi;Tahara, Keiji;Kawakami, Junichi;Madokoro, Kazuya;Nagamatsu, Takashi;Imai, Takaki;Harada, Nobuya;Kudo, Yu;Shiba, Naoto
    • Clinics in Shoulder and Elbow
    • /
    • v.23 no.2
    • /
    • pp.86-93
    • /
    • 2020
  • Background: Several systematic reviews have reported on the conservative treatment of full-thickness rotator cuff tears; however, clinical results of this treatment still remain determined. Methods: PubMed, Cochrane Library, PEDro, and CINAHL databases were systematically searched for randomized clinical trials and observational studies. Two independent researchers reviewed a total of 2,981 articles, 28 of which met the criteria for inclusion in the study. Clinical outcome measures included Constant score, visual analog scale score for pain, range of motion, and short-form 36 questionnaires. The meta-analysis used a linear mixed model weighted with the variance of the estimate. Results: The meta-analysis showed a significant improvement after surgery. Pain score is 26.2 mm (1 month) to 26.4 mm (3 months), and 24.8 mm (12 months) (P<0.05); active abduction: 153.2° (2 months), 159.0° (6 months), 168.1° (12 months) (P<0.05); Constant score: 67.8 points (2 months) to 77.2 points (12 months) (P<0.05); short-form 36 questionnaires "vitality" section: 57.0 points (6 months) to 70.0 points (12 months) (P<0.05). Conclusions: Our data confirmed the effectiveness of conservative treatment in patients with full-thickness rotator cuff tears 12 months post-intervention. The results suggest that conservative treatment for patients with full-thickness rotator cuff tears should be the first line of treatment before considering surgery.

Estimation of genetic parameters for temperament in Jeju crossbred horses

  • Kim, Nam Young;Son, Jun Kyu;Cho, In Cheol;Shin, Sang Min;Park, Seol Hwa;Seong, Pil Nam;Woo, Jae Hoon;Park, Nam Geon;Park, Hee Bok
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.31 no.8
    • /
    • pp.1098-1102
    • /
    • 2018
  • Objective: Temperament can be defined as a type of behavioral tendency that appears in a relatively stable manner in responses to various external stimuli over time. The aim of this study was to estimate genetic parameters for the records of temperament testing that are used to improve the temperament of Jeju crossbred (Jeju${\times}$Thoroughbred) horses. Methods: This study was conducted using 205 horses (101 females and 104 males) produced between 2010 and 2015. The experimental animals were imprinted and tamed according to the Manual for Horse Taming and Evaluation for Therapeutic Riding Horses and evaluated according to the categories for temperament testing (gentleness, patience, aggressiveness, sensitivity, and friendliness) between 15 months and 18 months of age. Each category was scored on a five-point linear scale. Genetic parameters for the test categories were analyzed using a multi-trait mixed model with repeated records. The ASReml program was used to analyze the data. Results: The heritability of gentleness, patience, aggressiveness, sensitivity and friendliness ranged from 0.08 to 0.53. The standard errors of estimated heritability ranged from 0.13 to 0.17. The test categories showed high genetic correlations with each other, ranging from 0.96 to 0.99 and high repeatability, ranging from 0.70 to 0.73. Conclusion: The results of this study showed that the test categories had moderate heritability and high genetic correlations, but additional studies may be necessary to use the results for the improvement programs of the temperament of Jeju crossbred horses.

Numerical Study of Face Plate-Type EPB Shield TBM by Discrete Element Method (개별요소법을 활용한 면판형 토압식 쉴드TBM의 수치해석 연구)

  • Lee, Chulho;Chang, Soo-Ho;Choi, Soon-Wook;Park, Byungkwan;Kang, Tae-Ho;Sim, Jung Kil
    • Journal of the Korean Geosynthetics Society
    • /
    • v.16 no.4
    • /
    • pp.163-176
    • /
    • 2017
  • The Discrete Element Method (DEM) has been widely used in civil engineering as well as various industrial fields to simulate granular materials. In this study, DEM was adopted to predict the performance of the face plate-type earth pressure balance (EPB) shield TBM (Tunnel Boring Machine). An analysis of the TBM excavation performance was conducted according to two pre-defined excavation conditions with the different rotation speeds per minute (RPM) of the cutterhead. The TBM model which was used in this study has a 6.64 m of diameter and six spokes. Also, 37 precutters and 98 scrapers at an each spoke were modeled with a real-scale specification. From the analysis, compressive forces at the cutterhead face, shield and cutting tools, resistant torques at the cutterhead face, muck discharge rate and accumulated muck discharge by the screw auger were measured and compared.