• Title/Summary/Keyword: Relative degree

Search Result 1,161, Processing Time 0.028 seconds

Structural response analysis in time and frequency domain considering both ductility and strain rate effects under uniform and multiple-support earthquake excitations

  • Liu, Guohuan;Lian, Jijian;Liang, Chao;Zhao, Mi
    • Earthquakes and Structures
    • /
    • v.10 no.5
    • /
    • pp.989-1012
    • /
    • 2016
  • The structural dynamic behavior and yield strength considering both ductility and strain rate effects are analyzed in this article. For the single-degree-of-freedom (SDOF) system, the relationship between the relative velocity and the strain rate response is deduced and the strain rate spectrum is presented. The ductility factor can be incorporated into the strain rate spectrum conveniently based on the constant-ductility velocity response spectrum. With the application of strain rate spectrum, it is convenient to consider the ductility and strain rate effects in engineering practice. The modal combination method, i.e., square root of the sum of the squares (SRSS) method, is employed to calculate the maximum strain rate of the elastoplastic multiple-degree-of-freedom (MDOF) system under uniform excitation. Considering the spatially varying ground motions, a new response spectrum method is developed by incorporating the ductility factor and strain rate into the conventional response spectrum method. In order to further analyze the effects of strain rate and ductility on structural dynamic behavior and yield strength, the cantilever beam (one-dimensional) and the triangular element (two-dimensional) are taken as numerical examples to calculate their seismic responses in time domain. Numerical results show that the permanent displacements with and without considering the strain rate effect are significantly different from each other. It is not only necessary in theory but also significant in engineering practice to take the ductility and strain rate effects into consideration.

Risk Factors for Premenopausal Breast Cancer: A Case-control Study in Uruguay

  • Ronco, Alvaro L.;Stefani, Eduardo De;Deneo-Pellegrini, Hugo
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.13 no.6
    • /
    • pp.2879-2886
    • /
    • 2012
  • In order to thoroughly analyze risk factors of breast cancer (BC) in premenopausal Uruguayan women, a case-control study was carried out at the Pereira Rossell Women's Hospital, Montevideo, where 253 incident BC cases and 497 frequency-matched healthy controls were interviewed on menstrual and reproductive story, were administered a short food frequency questionnaire and undertook a series of body measurements necessary to calculate body composition and somatotype. Odds ratio (OR) coefficients were taken as estimates of relative risk derived from unconditional logistic regression. Among the classical risk factors, only the family history of BC in first degree relatives was significantly associated with risk of premenopausal BC (OR=2.20, 95% CI 1.33-3.62). Interestingly, this risk factor was found to be stronger in women of ages >40 (OR=4.05, 95% CI 2.10-7.81), late menarche (OR= 2.39, 95% CI 1.18-4.85), early age for their first delivery (OR=3.02, 95% CI 1.26-7.22), short time between menarche and first delivery (OR=3.22, 95% CI 1.29-8.07), and with high parity (OR=4.10, 95% CI 1.79-9.36), although heterogeneity was detected only for age and parity. High consumption of red meat was positively associated with the disease risk (OR=2.20, 95% CI 1.35-3.60), in the same way as fried foods (OR=1.79, 95% CI 1.12-2.84). Conversely, a high intake of plant foods displayed a protective effect (OR=0.41, 95% CI 0.26-0.65). Except for hypertension (OR=1.55, 95% CI 1.03-2.35), none of the analyzed components of metabolic syndrome were associated to BC risk. Particular increases of risk for premenopausal BC were found for family history in first degree relatives in certain subsets derived from the menstrual-reproductive history. Preventive strategies could broaden their scope if new studies confirm the present results, in view of the limited prevention measures that premenopausal BC currently has.

Non-isothermal Crystallization Behavior of Poly(glycolide-co-ε-caprolactone-co-L-lactide) Block Copolymer (생체분해성 Poly(glycolide-co-ε-caprolactone-co-L-lactide) 블록 공중합물의 비등온 결정화 거동에 관한 연구)

  • Choi, Sei-Young;Song, Seung-Ho
    • Elastomers and Composites
    • /
    • v.49 no.1
    • /
    • pp.13-23
    • /
    • 2014
  • In this work, glycolide, L-lactide and ${\varepsilon}$-caprolactone monomers were polymerized into the triblock copolymers by two step polymerization method and their non-isothermal crystallization behaviors were studied by combination of modified Avrami and Ozawa formula for further analysis of their behaviors. The result showed that PGCLA21 gave the highest value for supercooling analysis and super cooling degree increased with L-lactide content. Crystallization velocity constant, however, showed no significant change. The result of cooling function in specific relative crystallization degree showed that the increase of L-lactide content made an effect on the more enhancement of crystallization velocity of the PGCLA than PGCL. The result of big logF(T) value with the L-lactide content above critical point for PGCLA41 and PGCLA21 showed that bigger cooling velocity needed to gain same crystal size compared with PGCL. This means that it gives negative effect in the increase of crystallization velocity.

Color Filter Utilizing a Thin Film Etalon (박막형 에탈론 기반의 투과형 컬러필터)

  • Yoon, Yeo-Taek;Lee, Sang-Shin
    • Korean Journal of Optics and Photonics
    • /
    • v.21 no.4
    • /
    • pp.175-178
    • /
    • 2010
  • A transmission type color filter based on a thin film Ag-$SiO_2$-Ag etalon was proposed and realized in a quartz substrate. The device could acquire infrared suppressed transmission and wide effective area compared to costly e-beam lithography and laser interference lithography. The FDTD method was introduced to take into account the effect of the dispersion characteristics of the silver metal and the thickness thereof. Three different color filters were devised: The cavity length for the red, green and blue filters were 160 nm, 130 nm, and 100 nm respectively, with the metal layer unchanged at 25 nm. The observed center wavelengths were measured at 650 nm, 555 nm, and 480 nm for the red, green, and blue devices; the corresponding bandwidths were about 120 nm, 100 nm, and 120 nm; and the peak transmission for all was ~60%. Finally the relative transmission was measured to decline with the angle of the incident beam with the rate of 1%/degree.

Assessing Breast Cancer Risk among Iranian Women Using the Gail Model

  • Khazaee-Pool, Maryam;Majlessi, Fereshteh;Nedjat, Saharnaz;Montazeri, Ali;Janani, leila;Pashaei, Tahereh
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.17 no.8
    • /
    • pp.3759-3762
    • /
    • 2016
  • Background: Breast cancer risk assessment is a helpful method for estimating development of breast cancer at the population level. Materials and Methods: In this cross-sectional study, participants consisted of a group of 3,847 volunteers ($mean{\pm}SD$ age: $463{\pm}7.59$ years) in a convenience sample of women referred to health centers affiliated to Tehran University of Medical Sciences in Tehran, Iran. The risk of breast cancer was estimated by applying the National Cancer Institute's online version of the Gail Risk Assessment Tool. Results: Some 24.9% of women reported having one first-degree female relative with breast cancer, with 8.05% of them having two or more first-degree relatives with breast cancer. The mean five-year risk of breast cancer for all participants was $1.61{\pm}0.73%$, and 9.36% of them had a five-year risk of breast cancer >1.66%. The mean lifetime risk of breast cancer was $11.7{\pm}3.91%$. Conclusions: The Gail model is useful for assessing probability of breast cancer in Iranian women. Based on the their breast cancer risk, women may decide to accept further screening services.

Laboratory Tests for the Applicability of Various Testing Devices for Measuring Degree of Compaction (여러가지 다짐 평가장비의 적용성을 위한 실내시험)

  • Yoo, Wan-Kyu;Lim, Nam-Gyu;Kim, Byoung-Il;Kim, Ju-Hyong
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2008.03a
    • /
    • pp.1178-1187
    • /
    • 2008
  • Quality assurance for embankment compaction is one of very important procedures to guarantee high quality construction. However, only sand replacement method (KS F2312) and static plate load test (KS F2310) which are conventional and tiresome methods are used to evaluate degree of compaction at construction fields. Recently, new types of devices such as the geogauge and the light falling weight deflectometer (LFWD), the soil impact hammer (CASPFOL) and dynamic cone penetration test etc. which are able to substitute for the conventional methods are begun to use to evaluate soil stiffness. In this study, a laboratory model test was performed to evaluate correlations among test results obtained from the new devices and to assess the potential use of them. All test results have correlations with relative density and water content. Especially, the coefficients of correlation between $E_G$ from the geogauge and $K_{30'}$ from the soil impact hammer and between $E_G$ from the geogauge and $E_{LFWD}$ from LFWD are more than 0.7 but those between the results from DCP and others are less than those between $E_{G{\cdot}}$ and $K_{30'}$ and $E_G$ and $E_{LFWD}$.

  • PDF

Elastic Wave Velocity of Jumunjin Sand Influenced by Saturation, Void Ratio and Stress (포화도, 간극비 및 응력에 따른 주문진사의 탄성파 속도)

  • Lee, Jung-Hwoon;Yun, Tae-Sup
    • Journal of the Korean Geotechnical Society
    • /
    • v.30 no.4
    • /
    • pp.101-106
    • /
    • 2014
  • The penetration testing provides 1 dimensional profiles of properties applicable to limited investigation areas, although N-value has been linked to a wide range of geotechnical design parameters based on empirical correlations. The nondestructive test using elastic waves is able to produce 2 or 3 dimensional property maps by inversion process with high efficiency in time and cost. As both N-value and elastic wave velocities share common dominant factors that include void ratio, degree of saturation, and in-situ effective stress, the correlation between the two properties has been empirically proposed by previous studies to assess engineering properties. This study presents the experimentally measured elastic wave velocities of Jumunjin sands under at-rest lateral displacement condition with varying the initial void ratio and degree of saturation. Results show that the stress condition predominantly influences the wave velocities whereas void ratio and saturation determine the stress-velocity tendency. The correlation among the dominant factors is proposed by multiple regression analysis with the discussion of relative impacts on parameters.

The Effects of Auricular Acupressure in Children's Obesity (이침요법(耳鍼療法)이 아동의 비만도(肥滿度)에 미치는 효과(效果))

  • Kim, Mi-Sook;Lee, Ji-Won;Youn, Hyoun-Min
    • Journal of Acupuncture Research
    • /
    • v.22 no.5
    • /
    • pp.99-109
    • /
    • 2005
  • Objectives : The purpose of this study was to examine the effects of Auricular acupressure with semen sinapis in obese children over a specific period of time. Methods : The study subjects included 27 obese children who were evaluated as such using Broca's Index at an elementary school located in M city. The data was collected throughout March 2, to May 31, 2005. In order to collect data, as a pre-test, characteristics of obesity and general characteristics were examined. Experimental treatments were used on Shinmun, Kijeom, Wijeom, Bijeom and Naebunbijeom. Among the auricular spots, one pill of semen sinapis was placed and pressed for five seconds at a time with exerted force and the subjects endured pain. This procedure was conducted ten tunes every morning, noon and evening for a period of six weeks. As a post-test, the degree of obesity were examined two weeks, four weeks and six weeks after acupressure had been applied. The data was collected and analysed using the SPSS/WIN 10.0 program by number, percentage, mean standard deviation, and Repeated Measure ANOVA. Result : The first hypothesis that 'The obesity of the children who had auricular acupressure with semen sinapis will show no difference over time' (two weeks, four weeks and six weeks after acupressure had been applied) was rejected(p=.000). A statistically significant difference in the obesity of the children who had auricular acupressure with semen sinapis was shown over time. The children's obesity degree reduced from 35.85% before auricular acupressure with semen sinapis to 28.67% six weeks after acupressure. Thus after six weeks of acupressure the relative degrees of obesity were reduced by 7.18%. Conclusion : Bases on the above results, it can be determined that auricular acupressure with semen sinapis can be used as an effective method of treatment in Korea, for reducing degrees of obesity in children.

  • PDF

A New Similarity Measure based on RMF and It s Application to Linguistic Approximation (상대적 소수 함수에 기반을 둔 새로운 유사성 측도와 언어 근사에의 응용)

  • Choe, Dae-Yeong
    • The KIPS Transactions:PartB
    • /
    • v.8B no.5
    • /
    • pp.463-468
    • /
    • 2001
  • We propose a new similarity measure based on relative membership function (RMF). In this paper, the RMF is suggested to represent the relativity between fuzzy subsets easily. Since the shape of the RMF is determined according to the values of its parameters, we can easily represent the relativity between fuzzy subsets by adjusting only the values of its parameters. Hence, we can easily reflect the relativity among individuals or cultural differences when we represent the subjectivity by using the fuzzy subsets. In this case, these parameters may be regarded as feature points for determining the structure of fuzzy subset. In the sequel, the degree of similarity between fuzzy subsets can be quickly computed by using the parameters of the RMF. We use Euclidean distance to compute the degree of similarity between fuzzy subsets represented by the RMF. In the meantime, we present a new linguistic approximation method as an application area of the proposed similarity measure and show its numerical example.

  • PDF

A Study on the Factors Influencing Alienation of the Aged (노인의 소외감에 영향을 미치는 관련변인 연구 - 서울시 거주 노인들을 대상으로)

  • 박의연;유영주
    • Journal of Families and Better Life
    • /
    • v.7 no.2
    • /
    • pp.199-212
    • /
    • 1989
  • The main purpose of this paper is to investigate the factors which affect the alienation of the aged, and to study the relative importance of these factors. This study focused on the following research questions: 1) How do the demographic variables(sex, marital status, family structure, religion, economics, prior occupation, education level) affect the alienation of the aged? 2) How the alienation of the aged is affected by their involvement in social activities? 3) Does the degree of satisfaction with family relationship have a perceivable impact on the alienation of the aged? 4) How does the self-rated senescence affect the alienation of the aged? The research was practiced from the 18th Sept. 1999 to the 30th Sept. 1988, through individual interviews with 300 elderly people, all living in Seoul area. Among them only 285 were used in the analysis. The major findings of the study are as follows; 1) The sex of the respondents makes no difference in the alienation of the age . 2) Marital status is found to be relatively significant in determining the alienation. The degree of alienation of old people with spouse is substantially lower than that of those without spouse. 3) Family structure was found to have no significantly effect on the alienation of the aged. 4) Involvement in religion was found to significantly reduce the alienation of the aged. 5) Econimic factors seems to be critical in defermining the aged. The amount of pocket money avaliable for daily use has direct relationship with alienation. 6) Prior occupation was found to be another significant factor affecting alienation professionals experience far lower alienation than nonprofessionals. 7) The higher is education level, the lower is the alienation of the aged. 8) Active participation in social activities and good relationship with other family members were founded to contribute to lowering the alienation of the aged. Whereas, too much concern over one's senescence appears to hav negative effects on the alienation. The regression analysis shows that the satisfaction with the family relationship has the most important influence upon the alienation of the aged. Following are the factors of self-rated senescence, pocket money in a descending order. All these factors, which explain 42.65% of the total variance of alienation variable are statistically significant(p<.001)

  • PDF