• Title/Summary/Keyword: Scale Factor Stability

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Stability Analysis and Reinforcement of Large Excavated Slope considering Precipitation Infiltration in Rainy Season (강우침투로 인한 대절취사면의 붕괴안정성검토 및 대책)

  • Chun, Byung-Sik;Choi, Hyun-Seok
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.4 no.1
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    • pp.101-110
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    • 2000
  • In case heavy rainfall is a key factor of slope failure, the failure zone is usually developed within the depth of 3~5m from the ground surface regardless of the location of the watertable. If rainfall is taken into consideration, it is general that the slope stability analysis is carried out under the assumption that the cut slope is saturated to the slope surface or the watertable elevates to a certain height so that ${\gamma}_{sat}$, the unit weight of saturated soil, is used. However, the analysis method mentioned above can't exactly simulate the variation of pore water pressure in the slope and yields different failure shape. The applicability of slope stability analysis method considering the distribution of pore water pressure within the slope with heavy rainfalls, was checked out after the stability analysis of a lage-scale cut slope in a highway construction site, where surface failure occurred with heavy rainfalls. An appropriate slope stabilization method is proposed on the base of the outcome of the analysis.

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Psychometric Properties of the Persian Version of the Self-Assessed Support Needs Questionnaire for Breast Cancer Cases

  • Ghaffari, Fatemeh;Shali, Mahboobeh;Shoghi, Mahnaz;Joolaee, Soodabeh
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.3
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    • pp.1435-1440
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    • 2014
  • Background: It has been found that support given to women with breast cancer has a positive effect upon their reactions to the illness and may even prolong their survival. Perceived support needs assessment in breast cancer women could be considered as a necessary part of nursing function. Aim: The purpose of this study was to translate and culturally adapt the self-assessed support needs (SASN) questionnaire into Persian language and to investigate its psychometric properties. Materials and Methods: After forward-backward translation of the questionnaire and making appropriate changes, we selected 160 women with breast cancer as our study sample. The psychometric properties of the SASN, including its internal consistency, test retest reliability, and construct validity were evaluated through the known-groups technique. Results: The calculated Kaiser Meyer Olkin was 0.756, indicating that the sample was sufficiently large to perform a satisfactory factor analysis. The six factors all together explained 50.7% of the variance; the first factor (diagnosing) explaining the biggest part of variance (10.9). Internal consistency reliability was 0.83 for the whole scale and the stability of test was 0.78. For the first factor, Cronbach's alpha was 0.90 and factor loadings of scale's items were found to deal with diagnosis subscale. The domains described patients' diagnosis, treatment, support, femininity and body image, family and friends and information. Conclusions: The reliability and validity of the adapted version of the SASN was shown to be satisfactory. Thus, it can be used to investigate self-assessed support needs of Iranian women suffering from breast cancer since the SASN is a multi-domain scale.

Characteristics of Lateral Flow due to Embankments for Road Construction on Soft Grounds Using Vertical Drain Methods (연직배수공법이 적용된 연약지반 상에 도로성토로 인한 측방유동의 특성)

  • Hong, Won-Pyo;Kim, Jung-Hoon
    • Journal of the Korean Geotechnical Society
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    • v.28 no.9
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    • pp.5-15
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    • 2012
  • Field monitoring data for embankments in thirteen road construction sites at coastal area of the Korean Peninsula were analyzed to investigate the characteristics of lateral flow in soft grounds, to which vertical drain methods were applied. First of all, the effect of the embankment scale on the lateral flow was investigated. Thicker soft soils and lager relative embankment scale produced more horizontal displacements in soft grounds. Especially, if thick soft grounds were placed, the relative embankment scale, which was given by the ratio of thickness of soft ground to the bottom width of embankments, became larger and in turn large horizontal displacement was produced. And also higher filling velocity of embankments induced more horizontal displacements in soft grounds. The other major factors affecting the lateral flow in soft ground were the thickness and undrained shear strength of soft grounds, the soil modulus and the stability number. Maximum horizontal displacement was induced by less undrained shear strength and soil modulus of soft grounds. Also more stability numbers produced more maximum horizontal displacements. When the shear deformation does not develop, the stability number was less than 3.0 and the safety factor of bearing was more than 1.7. However, if the stability number was more than 5.14 and the safety factor of bearing was less than 1.0, the unstable shear failure developed in soft ground. 50mm can be recommended as a criterion of the allowable maximum horizontal displacement to prevent the shear deformation in soft ground, while 100mm can be recommended as a criterion of the allowable maximum horizontal displacement to prevent the shear failure in soft ground.

Fabrication and evaluation of a silicon pendulous servo accelerometer (실리콘 펜듈럼 서보 가속도계의 제작 및 성능 평가)

  • 서재범;심규민;오문수;이관섭
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.56-60
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    • 1996
  • This paper presents the initial results of development of a inertial navigation grade silicon pendulous accelerometer. This effort focused on developing a bulk-micromachined silicon pendulum and designing a PI-servo controller. Performance data presented in this paper includes threshold, bias short term stability and nonlinearity of scale factor. This accelerometer developed is demonstrated the feasibility of meeting one-nautical-mile-per-hour accuracy.

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The Slope Reinforcement by use of FRP (FRP를 이용한 사면보강)

  • 이상덕;권오엽;최용기
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.11b
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    • pp.155-180
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    • 2000
  • The pattern of domestic slope construction has been steadily changed from the simpled and small-scale to the large-scale and complicated one, frequently near the existing structures, as the density of population and the traffic increases. In some cases, the slopes become steeper and larger due to the road improvement and construction. For the rock slope, the existence of discontinuity cannot be disregarded and acts as an important factor on the slope stability. Most of the existing methods for stabilizing the slope were focused on reducing the slope angle. Under the specific geographic condition, it is necessary to concentrate more efforts on the research and development of supporting system for the slope stability. As a supporting system, it is often very advantageous to use the FRP pipe grouting method that is similar to the existing soil nailing method or the rock bolting method but uses the high strength FRP pipe as a principal reinforcement in place of steel bar. Through the FRP pipe, the grout material can be injected into the rock mass to improve its shear strength to the required value. .In this study, the characteristics of FRP are investigated by the laboratory tests and the field tests. And, the practical aspects of FRP method are reviewed and analyzed.

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Development of a Nursing Professional Values Scale (간호전문직관 측정도구 개발)

  • Yeun, Eun-Ja;Kwon, Young-Mi;Ahn, Ok-Hee
    • Journal of Korean Academy of Nursing
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    • v.35 no.6
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    • pp.1091-1100
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    • 2005
  • Purpose: The purpose of this study was to develop an instrument to measure nursing professional values. Method: Forty preliminary items were selected by classifying 223 basic items extracted via a literature study and in-depth interviews of subjects and testing the relevance of their contents. In order to verify the reliability and relevance of the preliminary instrument, data was collected from 504 nurses in 3 general hospitals. Result: As a result of the item analysis, 29 items were selected from a total of 40 items. Five factors were extracted by factor analysis, and the total variance was $51.5\%$. For the explanation of variances by factors, the 1 st factor, 'self-concept of the profession' accounted for $14.8\%$, the 2nd factor, 'social awareness' $12.1\%$, the 3rd factor, 'professionalism of nursing' $9.8\%$, the 4th factor, 'the roles of nursing service' $9.1\%$, and the 5th factor, 'originality of nursing', $5.6\%$. Cronbach's Alpha of those 29 items was .9168, which was high. Conclusion: This paper is meaningful in a way that it developed a tool capable of measuring nursing professional values, which reflects the characteristics of our country. In order to re-verify the relevance and stability of this tool, it is necessary that comparative studies should be conducted.

A Study on the Behaviour Modes of the Face and Unsupported Span for Weak Rock Tunnel (연암터널의 막장 및 무지보 구간의 거동형태에 관한 연구)

  • Lee, Young-Zoo;Kim, Chang-Yong;Kim, Kwang-Yeom;Schubert, Wulf
    • Tunnel and Underground Space
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    • v.17 no.1 s.66
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    • pp.9-16
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    • 2007
  • The influence of round length on the tunnel stability and construction cost is well acknowledged by many researchers and engineers but the coherent procedure is not available for its determination. In this study, the behaviour modes of the face and unsupported span was investigated for weak rock tunnel by a small scale model test, PFC3D and FDM analyses in consideration of the round length. Total five types of behaviour modes are defined and quantitative estimation of the behaviour modes was established in terms of the safety factor for the face stability and the conditional chart. Although the proposed method has some restrictions, this method can provide useful information for the optimization of the round length and excavation, especially in design stage.

The Effects of Amendments on Composting of Swine Carcass (부자재가 돼지 사체 퇴비화에 미치는 영향)

  • 홍지형;최병민
    • Journal of Animal Environmental Science
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    • v.5 no.1
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    • pp.45-52
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    • 1999
  • The purpose of this study is to provide information for the livestock for the livestock carcass composting operation in agricultural waste management. Burial, landfilling and incineration of livestock carcass may have environmental regulatory and economic liabilities. Dead animals amended with agricultural residues can be composted and used to promote soil fertility and reduce environmental pollution. In this study we evaluated the effect of amendments on the primary and secondary composting reaction and stability of compost. The full-scale composting bin of swine carcass in roofed system with three amendments was adequate in reaching sufficient temperature above 55$^{\circ}C$ long enough to kill the pathogen. The average temperature of the compost material in dead swine amended with corn stover increased rapidly to 64$^{\circ}C$ on the 2nd day after primary composting and dropped to near ambient temperature on the 140th day of composting. The composting with of corn stover and wheat straw are more efficient for swine carcass composting than that of sawdust. Therefore, the amendment property is an important factor in the design of composting facility.

Stability Analysis of Marangoni Convection for $NH_3\;-H_2O$ Absorption Process (전파이론을 통한 $NH_3\;-H_2O$ 흡수과정의 마란고니 대류 안정성 해석)

  • 최창균;김제익;강용태
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.14 no.6
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    • pp.450-455
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    • 2002
  • Convective instability driven by surface tension is analyzed in an initially quiescent water absorbing ammonia gas using the linear stability theory. The propagation theory is adapated to find the critical conditions of the onset of solutal Maragoni convection. In this theory, the solutal penetration depth is chosen as the length scale factor. The results show that the liquid layer becomes more stable with decreasing the Schmidt number It is interesting that for a smaller Biot number than 100, the system becomes stable with decreasing Bi but for a larger Bi, it becomes unstable with decreasing Bi.

Development and Validation of Adaptive Game Use Scale (AGUS) (적응적 게임활용 척도 개발 및 타당화)

  • Hoon-Seok Choi ;Kyo-Heon Kim ;Joung Soon Ryong ;Keum-Mi Kim
    • Korean Journal of Culture and Social Issue
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    • v.15 no.4
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    • pp.565-589
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    • 2009
  • The present study explored the major components of adaptive game behavior among adolescents in Korea. Based on relevant research and a pilot testing, an Adaptive Game Use Scale (AGUS) was developed and validated. A stratified sampling procedure was used to draw a representative sample, and a total of 600 male and female students from middle schools and high schools in various regions participated in the study. Factor analyses revealed 7 facets of adaptive game behavior, including experiencing vitality, expanding life experience, making good use of leisure time, experiencing flow, exercising control, experiencing self-esteem, maintaining and expanding social network. Internal consistency and temporal stability(4 weeks) of the scale were both high. A confirmatory factor analysis indicated that a 7-factor hierarchical model fits well with the data. Moreover, additional analyses suggested that AGUS and game addiction are conceptually distinct. Correlational analyses also indicated that AGUS has good discriminant validity and concurrent validity. Implications of the findings and future directions were discussed.

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