• Title/Summary/Keyword: the mean

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Effect of Mean Stress on Fatigue Properties in Spring Steel (스프링강의 피로 특성에 미치는 평균 응력의 영향)

  • Seok, Chang-Sung;Kim, Hyung-Ick;Chang, Pil-Soo;Joo, Jae-Man;Kang, Jeong-Hoon
    • Proceedings of the KSME Conference
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    • 2003.04a
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    • pp.255-260
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    • 2003
  • Most of the fatigue test were achieved in fully reversed condition that mean stress is zero. But, generally, mean stress can not be zero. This research was achieved the bending fatigue test that changes mean stress to spring steel and was studied relation with the mean stress and the fatigue life. The method to search effect about mean stress was extended S-N graph in two cases. One method was extended S-N graph using modified Miner's rule with considering damage. Another was extended using tendency of S-N graph. The exponential value(${\alpha}$) of mean stress-alternating stress equation is converged between the Goodman's and the Gerber's value even if fatigue life increases.

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Dynamic Production Scheduling for JIT Delivery in a Welding Shop Adopting Batch-Production (뱃치생산을 하는 용접작업장에서 JIT 납품을 위한 동적생산일정계획)

  • Moon, Dug-Hee
    • IE interfaces
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    • v.10 no.2
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    • pp.57-67
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    • 1997
  • This paper is a report of a simulation study that investigates a dynamic approach to scheduling jobs in a conventional shop floor, especially in an assemoly-type welding process. We consider both JIT arrival and JIT delivery. Various dispatching rules are tested for the following performance measures; mean flow time, rate of tardy jobs, mean tardiness, sum of mean tardiness and mean earliness. The results indicate that SPT rule is the best for the mean flow time. MSLACK that we suggest in this paper, is the best for the mean tardiness and the sum of mean tardiness and mean earliness. However, it is not clear that which rule is the best for the rate of tardy jobs.

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Robust Mean-Shift Tracking Using Adoptive Selection of Hue/Saturation (Hue/Saturation 영상의 적응적 선택을 이용한 강인한 Mean-Shift Tracking)

  • Park, Han-dong;Oh, Jeong-su
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.05a
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    • pp.579-582
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    • 2015
  • The Mean-Shift is a robustness algorithm that can be used for tracking the object using the similarity of histogram distributions of target model and target candidate. However, Mean-shift using hue information has disadvantage of tracking a wrong target when the target and background has similar hue distributions. We then propose a robust Mean-Shift tracking algorithm using new image that combined upper 4bit-planes in hue and saturation, respectively.

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Tensile Mean Strain Effects on the Fatigue Life of SiC-Particulate-Reinforced Al-Si Cast Alloy Composites (SiC입자강화 주조Al-Si복합재의 피로수명에 대한 인장평균변형률의 영향)

  • Go, Seung-Gi
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.23 no.11 s.170
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    • pp.1970-1981
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    • 1999
  • The low-cycle fatigue behaviour of a SiC-particulate-reinforced Al-Si cast alloy with two different volume fractions has been investigated from a series of strain-control led fatigue tests with zero and nonzero tensile mean strains. The composites including the unreinforced matrix alloy, exhibited cyclic hardening behaviour, with more pronounced strain-hardening for the composites with a higher volume fraction of the SiC particles. For the tensile mean strain tests, the initial high tensile mean stress relaxed to zero for the ductile Al-Si alloy, resulting in no influence of the tensile mean strain on the fatigue life of the matrix alloy. However, tensile mean strain for the composite caused tensile mean stresses and reduced fatigue life. The pronounced effects of mean strain on the low-cycle fatigue life of the composite compared to the unreinforced matrix alloy were attributed to the initial large prestrain and non-relaxing high tensile mean stress in the composite with very limited ductility and Cyclic plasticity. Fatigue damage parameter using strain energy, density efficiently accounted for the mean stress effects. Predicted fatigue life using the damage parameter correlated fairly well with the experimental life within a factor of 3. Also, the fatigue damage parameter indicated the inferior life in the low-cycle regime and superior life in the high-cycle regime for the composite, compared to the unreinforced matrix alloy.

Investigating Arithmetic Mean, Harmonic Mean, and Average Speed through Dynamic Visual Representations

  • Vui, Tran
    • Research in Mathematical Education
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    • v.18 no.1
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    • pp.31-40
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    • 2014
  • Working with dynamic visual representations can help students-with-computer discover new mathematical ideas. Students translate among multiple representations as a strategy to investigate non-routine problems to explore possible solutions in mathematics classrooms. In this paper, we use the area models as new representations for our secondary students to investigate three problems related to the average speed of a particle. Students show their ideas in the process of investigating arithmetic mean, harmonic mean, and average speed through their created dynamic figures. These figures really utilize dynamic geometry software.

Hematological Reference Values in the Healthy Adults (건강성인의 혈구 참고치 산정)

  • Kim, Young-Jin;Hyun, Myung-Soo;Lee, Hyun-Woo
    • Journal of Yeungnam Medical Science
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    • v.8 no.1
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    • pp.154-165
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    • 1991
  • To establish the hematological reference values in the healthy adults visited our hospitals, following examination were done on 2823 persons by Coulter Counter Model S-plus II ; white blood cell count: (WBC), red blood cell count(RBC), hemoglobin(Hb), hematocrit(Hct), mean corpuscular volume (MCV), mean corpuscular hemoglobin(MCH), mean corpuscular hemoglobin concentration(MCHC), red cell distribution width(RDW), platelet, plateletcrit, mean platelet volume(MPV) and platelet distribution width(PDW). The following results are obtained. 1) Male, mean value of WBC ; $6,800{\pm}2,680(2SD)/{\mu}l$ Female, mean value of WBC ; $5,950{\pm}2,380(2SD)/{\mu}l$ 2) Male, mean value of RBC ; $428{\pm}60(2SD){\times}10^4/{\mu}l$ Female, mean value of WBC ; $415{\pm}56(2SD){\times}10^4/{\mu}l$ 3) Male, mean value of Hb ; $15.4{\pm}1.8(2SD)g/dL$ Female, mean value of Hb ; $13.0{\pm}1.6(2SD)g/dL$ 4) Male, mean value of Hct ; $45.3{\pm}5.0(2SD)%$ Female, mean value of Hct ; $38.2{\pm}4.6(2SD)%$ 5) Male, mean value of MCV ; $93.8{\pm}5.8(2SD)fL$ Female, mean value of MCV ; $92.2{\pm}7.4(2SD)fL$ 6) Male, mean value of MCH ; $31.8{\pm}2.2(250)pg$ Female, mean value of MCH ; $31.4{\pm}2.8(2SD)pg$ 7) Male, mean value of MCHC ; $34.0{\pm}1.2(2SD)%$ Female, mean value of MCHC ; $33.9{\pm}1.2(2SD)%$ 8) Male, mean value of RDW ; $12.7{\pm}1.0(2SD)%$ Female, mean value of RDW ; $12.6{\pm}1.4(2SD)%$ 9) Male, mean value of Platelet ; $242.9{\pm}87.8(2SD){\times}10^3/{\mu}l$ Female, mean value of Platelet ; $242.2{\pm}89.0(2SD){\times}10^3/{\mu}l$ 10) Male, mean value of Plateletcrit ; $0.201{\pm}0.076(2SD)%$ Female, mean value of Plateletcrit ; $0.204{\pm}0.076(2SD)%$ 11) Male, mean value of MPV ; $8.20{\pm}1.70(2SD)fl$ Female, mean value of MPV ; $8.36{\pm}1.82(2SD)fl$ 12) Male, mean value of PDW ; $16.1{\pm}0.8(2SD)%$ Female, mean value of PDW ; $16.0{\pm}0.8(2SD)%$.

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On the comparison of mean object size in M/G/1/PS model and M/BP/1 model for web service

  • Lee, Yongjin
    • International Journal of Internet, Broadcasting and Communication
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    • v.14 no.3
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    • pp.1-7
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    • 2022
  • This paper aims to compare the mean object size of M/G/1/PS model with that of M/BP/1 model used in the web service. The mean object size is one of important measure to control and manage web service economically. M/G/1/PS model utilizes the processor sharing in which CPU rotates in round-robin order giving time quantum to multiple tasks. M/BP/1 model uses the Bounded Pareto distribution to describe the web service according to file size. We may infer that the mean waiting latencies of M/G/1/PS and M/BP/1 model are equal to the mean waiting latency of the deterministic model using the round robin scheduling with the time quantum. Based on the inference, we can find the mean object size of M/G/1/PS model and M/BP/1 model, respectively. Numerical experiments show that when the system load is smaller than the medium, the mean object sizes of the M/G/1/PS model and the M/BP/1 model become the same. In particular, when the shaping parameter is 1.5 and the lower and upper bound of the file size is small in the M/BP/1 model, the mean object sizes of M/G/1/PS model and M/BP/1 model are the same. These results confirm that it is beneficial to use a small file size in a web service.

Emergency Medical Technology Curriculum Development for college (응급구조와 교과과정 개발)

  • Kim, Sun-Sim;Jung, Myung-Ae
    • The Korean Journal of Emergency Medical Services
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    • v.12 no.2
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    • pp.5-26
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    • 2008
  • Purpose : This study was performed to develop the curriculum of Emergency Medical technology of College. Method : The authors analyzed curricular of EMT in 12 college in Korea. We conducted the distribution, credit, mean, frequency of liberal arts, majors, teaching profession subject by Kim and Lee(2007). We compared curriculum of knowledge and clinical training courses. Results : The numbers of whole subjects were 59.3 and the number of mean and the credits were 130.8 degree of mean. The numbers of liberal arts were 9.5 number of mean and the credits were 15.5 degree of mean. The numbers of major were 47.5 number of mean and the credits were 111.4 degree of mean. The numbers of teaching profession subject were 1.9 number of mean and the credits were 4 degree of mean. Finally, frequency of curriculum of knowledge and clinical training courses were 57.1% and 42%, respectively. Conclusion : This results will represent curriculum development and will standardize curriculum for EMT collage. in addition, it will make EMT curriculum standardized.

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Estimation of Reservoir Inflow Using Frequency Analysis (빈도분석에 의한 저수지 유입량 산정)

  • Maeng, Seung-Jin;Hwang, Ju-Ha;Shi, Qiang
    • Journal of The Korean Society of Agricultural Engineers
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    • v.51 no.3
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    • pp.53-62
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    • 2009
  • This study was carried out to select optimal probability distribution based on design accumulated monthly mean inflow from the viewpoint of drought by Gamma (GAM), Generalized extreme value (GEV), Generalized logistic (GLO), Generalized normal (GNO), Generalized pareto (GPA), Gumbel (GUM), Normal (NOR), Pearson type 3 (PT3), Wakeby (WAK) and Kappa (KAP) distributions for the observed accumulative monthly mean inflow of Chungjudam. L-moment ratio was calculated using observed accumulative monthly mean inflow. Parameters of 10 probability distributions were estimated by the method of L-moments with the observed accumulated monthly mean inflow. Design accumulated monthly mean inflows obtained by the method of L-moments using different methods for plotting positions formulas in the 10 probability distributions were compared by relative mean error (RME) and relative absolute error (RAE) respectively. It has shown that the design accumulative monthly mean inflow derived by the method of L-moments using Weibull plotting position formula in WAK and KAP distributions were much closer to those of the observed accumulative monthly mean inflow in comparison with those obtained by the method of L-moment with the different formulas for plotting positions in other distributions from the viewpoint of RME and RAE.

A Study on Degree of Importance in Nursing Activities for the Quality of Nursing (질적간호 제공을 위한 간호업무 중요도에 관한 조사연구)

  • 홍춘실;김종임
    • Journal of Korean Academy of Nursing
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    • v.14 no.2
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    • pp.19-27
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    • 1984
  • This study was carried out for the purpose of investigating the degree of importance in nursing activities for the quality of nursing, and was conducted with 72 nurses and 69 patients in Chungnam National University Hospital from January to April, 1984. The results are as follows; 1. The mean importants score in physical care activities of the patients (2.58) is higher than that of the nurses (2.48). There is not significant difference for the mean important score in physical care activities between the patients and nurses (t=0.637, df=139, p>0.05). 2. The mean important score in psychological aspects of activities of the patients (2.94) is higher than that of the nurses (2.44). There is a significant difference for the mean important score in psychological aspects of activities between the patients and nurses (t=2.338, df= 139, p<0.05). 3. The mean important score in observation, recording and implementing medical care activities of the nurses (2.98) is higher than that of the patients (2.79) There is not significant difference for the mean important score in observation, recording and Implementing medical care activities between the patients and nurses (t=1.329, df=139, p> 0.05) 4. The mean important score in nursing management activities of the nurses (2.63) is higher than that of the patients (2.57). There is not significant difference for the mean important score in nursing management activities between the patients and nurses (t=1.329, df=139, p>0.05). 5. A number of items in nursing activities considered most important by nurses (Mean important score of 3.0 or above) were 12 items. The most importants item was“shift and exchange of information concerning patient”. 6. A number of items in nursing activities considered most important by patients (mean important score of 3.0 or above) were 14 items. The most important item was“Explain about diagnostic test ahead of time”. 7. A number of items in nursing activities considered least important by nurses and patients(Mean important score less than 1.9) were 5 items and 2 items, respectively. The least important item by nurses was“plan some diversion or recreation for patient”, and the least important item by patients was“Give a bed shampoo”.

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