• Title/Summary/Keyword: Stability criterion

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Translation and Validation of the Activities of Daily Living Scale with Iranian Elderly Cancer Patients Treated in an Oncology Unit

  • Khoei, Mahtab Alizadeh;Akbari, Mohammad Esmail;Sharifi, Farshad;Fakhrzadeh, Hossein;Larijani, Bagher
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.5
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    • pp.2731-2737
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    • 2013
  • Background: This study evaluated the validity and reliability of applying the Katz's Activities of Daily Living (ADL) scale in an Iranian sample of elderly oncologic patients following initial cancer treatment. Materials and Methods: The scale was translated with the forward-backward procedure to give an Iranian version. The ADL scale was then applied in a random sample of 400 oncologic patients aged 60 and older following initial cancer treatment. Assessment of the scale stability was twice, with a 14-days (two weeks) interval, to 30 (of the 400) eligible elderly cancer patients in March 2012. To measure treatment effects, the index was run with 150 patients in a three month recall, following oncology processing. Exploratory and confirmatory factor analysis was performed for assessment of construct validity of the Katz's ADL. Reliability was measured with internal consistency (Cronbach's alpha co-efficient), and test/retest (Spearman's r value) of the instrument. Criterion validity was evaluated by comparing the Katz with Physical Function (PF) subscale of SF 36. Known-group validity was approved by comparing of Katz' ADL between quartile groups of PF subscale of SF 36. Results: In our study the ADL demonstrated a high degree of internal homogeneity (Cronbach's alpha 0.923). There was a high correlation between scores of two time measurement of Katz's ADL (p value of two- related- samples test was 0.3). Construct validity showed a correlation coefficient of 0.572 between the ADL and PF scores. In factor analysis, 2 factors were extracted. Evidence for the reliability of the questionnaire was good and known group validity was approved by significant differences of ADL score between quartiles of the PF subscale of SF36. Conclusions: The results suggest that the Iranian version of ADL applied for oncologic older adult patients following initial cancer treatment is a reliable and a valid clinical instrument and comparable to those reported in other studies.

Failure Function of Transversely Isotropic Rock Based on Cassini Oval (Cassini 난형곡선을 활용한 횡등방성 암석 파괴함수)

  • Lee, Youn-Kyou
    • Tunnel and Underground Space
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    • v.27 no.4
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    • pp.243-252
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    • 2017
  • Since the failure behavior of transversely isotropic rocks is significantly different from that of isotropic rocks, it is necessary to develop a transversely isotropic rock failure function in order to evaluate the stability of rock structures constructed in transversely isotropic rock masses. In this study, a spatial distribution function for strength parameters of transversely isotropic rocks is proposed, which is based on the Cassini oval curve proposed by 17th century astronomer Giovanni Domenico Cassini to model the orbit of the Sun around the Earth. The proposed distribution function consists of two model parameters which could be identified through triaxial compression tests on transversely isotropic rock samples. The original Mohr-Coulomb (M-C) failure function is extended to a three-dimensional transversely isotropic M-C failure function by employing the proposed strength parameter distribution function for the spatial distributions of the friction angle and cohesion. In order to verify the suitability of the transversely isotropic M-C failure function, both the conventional triaxial compression and true triaxial compression tests of transversely isotropic rock samples are simulated. The predicted results from the numerical experiments are consistent with the failure behavior of transversely isotropic rocks observed in the actual laboratory tests. In addition, the simulated result of true triaxial compression tests hints that the dependence of rock strength on intermediate principal stress may be closely related to the distribution of the microstructures included in the rock samples.

Calculation of Failure Load of V-shaped Rock Notch Using Slip-line Method (Slip-line법을 이용한 V형 암석 노치의 파괴하중 계산)

  • Lee, Youn-Kyou
    • Tunnel and Underground Space
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    • v.30 no.4
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    • pp.404-416
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    • 2020
  • An analytical procedure for calculating the failure load of a V-shaped rock notch under two-dimensional stress conditions was developed based on the slip-line plastic analysis method. The key idea utilized in the development is the fact that the α-line, one of the slip-lines, extends from the rock notch surface to the horizontal surface outside the notch when the rock around the notch is in the plastic state, and that there exists an invariant which is constant along the α-line. Since the stress boundary condition of the horizontal surface outside the rock notch is known, it is possible to calculate the normal and shear stresses acting on the rock notch surface by solving the invariant equation. The notch failure load exerted by the wedge was calculated using the calculated stress components for the notch surface. Rock notch failure analysis was performed by applying the developed analytical procedure. The analysis results show that the failure load of the rock notch increases with exponential nonlinearity as the angle of the notch and the friction of the notch surface increase. The analytical procedure developed in this study is expected to have applications to the study of fracture initiation in rocks through wedge-shaped notch formation, calculation of bearing capacity of the rock foundation, and stability analysis of rock slopes and circular tunnels.

A Study on Consistency of Numerical Solutions for Wave Equation (파동방정식 수치해의 일관성에 관한 연구)

  • Pyun, Sukjoon;Park, Yunhui
    • Geophysics and Geophysical Exploration
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    • v.19 no.3
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    • pp.136-144
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    • 2016
  • Since seismic inversion is based on the wave equation, it is important to calculate the solution of wave equation exactly. In particular, full waveform inversion would produce reliable results only when the forward modeling is accurately performed because it uses full waveform. When we use finite-difference or finite-element method to solve the wave equation, the convergence of numerical scheme should be guaranteed. Although the general proof of convergence is provided theoretically, the consistency and stability of numerical schemes should be verified for practical applications. The implementation of source function is the most crucial factor for the consistency of modeling schemes. While we have to use the sinc function normalized by grid spacing to correctly describe the Dirac delta function in the finite-difference method, we can simply use the value of basis function, regardless of grid spacing, to implement the Dirac delta function in the finite-element method. If we use frequency-domain wave equation, we need to use a conservative criterion to determine both sampling interval and maximum frequency for the source wavelet generation. In addition, the source wavelet should be attenuated before applying it for modeling in order to make it obey damped wave equation in case of using complex angular frequency. With these conditions satisfied, we can develop reliable inversion algorithms.

Design of Portable Welded-Nitrogen Vessel (11 kg, 10 L and 50 bar) for Shipbuilding (선박용 휴대형 질소용기(11 kg, 10 L 및 50 bar)의 두께 및 외형 설계)

  • Seong, Hansaem;Kim, Jaeyeol;Eom, Taejin;Kawk, Hyo Seo;Lee, Kwang O;Kim, Chul
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.4
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    • pp.263-270
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    • 2017
  • The shipbuilding industry uses large stationary tanks to store low-pressure air, which is used to open and close large shut-off valves. However, when supplying air from the tank to a distant valve, there are problems related to the need for supplementary pipes and the pressure drop during transportation. In this study, a portable welded vessel for storing high-pressure nitrogen (11 kg, 10 L, and 50 bar) was designed to prevent air leakage and improve the convenience of workers. This pressure vessel was elliptical to reduce the number of welded parts, which are structurally weak. The thickness and ratio of the major and minor axes of the pressure vessel were calculated to verify its structure stability at the working pressure (50 bar), and that the proposed weight and capacity were satisfactory. The residual stress caused by the welding process was calculated by performing a transient thermal-structural coupled field analysis using the ANSYS parametric design language (APDL), and the fatigue life of the vessel was verified based on the Goodman criterion.

Development and Validation of the Scale of Care Competence for Adolescent (청소년 돌봄역량 측정도구의 개발 및 타당화)

  • Lee, Jisun;Choi, Saeeun
    • Journal of Korean Home Economics Education Association
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    • v.35 no.2
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    • pp.111-132
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    • 2023
  • The objective of this research is to conceptualize care competences for adolescents and to develop a valid measurement tool based on this conceptualization. The primary aim is to establish a solid foundation for effective communication in teaching care competences within the domain of home economics education. To achieve this, a comprehensive review of relevant literature and previous studies was conducted, and consultations with experts were undertaken to assess content and criterion-related validity. Furthermore, exploratory and confirmatory factor analyses were performed. The findings from these analyses resulted in a set of 34 items, which were categorized into five distinctive factors representing care competences in adolescents. These factors encompassed four items of care thinking, seven items of care emotion, six items of care behavior, seven items of self-care and ten items of community-care. Additionally, a reliability analysis was performed on the model, confirming the stability and consistency of the five factor structure and the 34 item scale, which assess care competences in adolescents.

A Study on the Evaluation of Distribution Stability of Refrigerated Rice Cake Using Natural Antibiotics (천연항균제를 사용한 냉장떡류의 유통 안정성 평가연구)

  • Yoo, Seung Jin;Chin, Jong-eon;Oh, Sung Hoon;Ryu, Min Jung;Hwang, Kwontack
    • Journal of Chitin and Chitosan
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    • v.23 no.4
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    • pp.244-255
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    • 2018
  • Natural extract in liquid phase was adjusted to 0, 0.25, 0.5, 1, 2, and 4% concentration to check microbial changes and to measure 4, 8, $12^{\circ}C$ for refrigeration temperature. In the case of grapefruit extract, the microbial safety was maintained at all the concentrations at $4^{\circ}C$ storage, but the antimicrobial activity was maintained at $12^{\circ}C$ storage and at $8^{\circ}C$ and 21 days storage. In the case of grape seed extract, only the 4% of the culture at $8^{\circ}C$ satisfied the requirement of safety of food distribution for the last 21 days, and the safety criterion was satisfied only at 4% concentration at $12^{\circ}C$ for 18 days. Complex Scutellaria baicalensis extract showed the total number of microbial cells treated by concentration. It was confirmed that microbial flow safety was maintained at low temperature ($4^{\circ}C$). However, at $8^{\circ}C$ and $12^{\circ}C$, Exceeded the distribution limit. When polylysine was applied to brown rice cake, it showed activity in all groups except $4^{\circ}C$, but these properties were not observed at $8^{\circ}C$ and $12^{\circ}C$. At a concentration of 0.5% or more of chitosan, the growth of the microorganism is suppressed by the 21st day very stably, and a similar tendency is observed at 8 and $12^{\circ}C$, so that it may be an antimicrobial material that inhibits microorganisms. At the first day, the distribution standards for general bacterial counts were exceeded.Ethyl-pyruvate showed that microorganism safety was maintained at $4^{\circ}C$ and 1% concentration, and food safety was stable even at 2 or 4%. Glycine showed very good and stable distribution stability at $4^{\circ}C$. However, at $8^{\circ}C$ and $12^{\circ}C$, the shelf life of 14 days could not be maintained as with the addition of other antimicrobial active substances.

Studies on Development of Prediction Model of Landslide Hazard and Its Utilization (산지사면(山地斜面)의 붕괴위험도(崩壞危險度) 예측(豫測)모델의 개발(開發) 및 실용화(實用化) 방안(方案))

  • Ma, Ho-Seop
    • Journal of Korean Society of Forest Science
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    • v.83 no.2
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    • pp.175-190
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    • 1994
  • In order to get fundamental information for prediction of landslide hazard, both forest and site factors affecting slope stability were investigated in many areas of active landslides. Twelve descriptors were identified and quantified to develop the prediction model by multivariate statistical analysis. The main results obtained could be summarized as follows : The main factors influencing a large scale of landslide were shown in order of precipitation, age group of forest trees, altitude, soil texture, slope gradient, position of slope, vegetation, stream order, vertical slope, bed rock, soil depth and aspect. According to partial correlation coefficient, it was shown in order of age group of forest trees, precipitation, soil texture, bed rock, slope gradient, position of slope, altitude, vertical slope, stream order, vegetation, soil depth and aspect. The main factors influencing a landslide occurrence were shown in order of age group of forest trees, altitude, soil texture, slope gradient, precipitation, vertical slope, stream order, bed rock and soil depth. Two prediction models were developed by magnitude and frequency of landslide. Particularly, a prediction method by magnitude of landslide was changed the score for the convenience of use. If the total store of the various factors mark over 9.1636, it is evaluated as a very dangerous area. The mean score of landslide and non-landslide group was 0.1977 and -0.1977, and variance was 0.1100 and 0.1250, respectively. The boundary value between the two groups related to slope stability was -0.02, and its predicted rate of discrimination was 73%. In the score range of the degree of landslide hazard based on the boundary value of discrimination, class A was 0.3132 over, class B was 0.3132 to -0.1050, class C was -0.1050 to -0.4196, class D was -0.4195 below. The rank of landslide hazard could be divided into classes A, B, C and D by the boundary value. In the number of slope, class A was 68, class B was 115, class C was 65, and class D was 52. The rate of landslide occurrence in class A and class B was shown at the hige prediction of 83%. Therefore, dangerous areas selected by the prediction method of landslide could be mapped for land-use planning and criterion of disaster district. And also, it could be applied to an administration index for disaster prevention.

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Comparative Review on the Introduction and Operation of Salary Peak System -Focusing on Korea and Japan- (임금피크제 도입운영에 관한 비교법적 검토 -한국과 일본을 중심으로-)

  • Noh, Jae-Chul
    • The Journal of the Korea Contents Association
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    • v.15 no.11
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    • pp.93-103
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    • 2015
  • In this study, it has an intention of arranging an implication based on an effective introduction of a wage peak system in Japan to settle a mandatory retirement at sixty according to a legalization of retirement age at sixty smoothly. Institutionally, retirement age guaranteed type that reduces wage from certain period before retirement is of great importance. In Japan, mainly features the extension of retirement age that focus on keeping aged employment after retirement. In the introduction of the wage peak system, Korea attaches importance to the wage cost savings, but Japan puts emphasis on using aging workforce. Korea wants to promote the aged employment for retirement age at 60, whereas Japan actively push ahead with retirement age 65 and after that time. South Korea needs to reinforce the pensionable age and the connection though the extension of retirement age via the manpower utilization, employment promotion and the stability. It is necessary to prepare a institutional plan to try not to make a gap of the pensions by guaranteeing or extending the retirement age connect to the age of pensioners though the wage peak system. To activate the wage peak system, it is necessary to acknowledge a legal improvement that concedes rational changes such as the rule of employment. An active interpretation is needed currently though, it is more necessary to review the stipulation and the rational changes of the rule of employment that is established by a precedent like the Japanese legislation case. When a disadvantageous change of works rules is made, it is able to consider establishing the provision in the Act on age Discrimination Prohibition in Employment and Aged Employment Promotion, therefore it won't be able to apply the regulation in the rational criterion that satisfies the standards, rather than amending a Article 94 of the Labor Standards Act that makes accepting the approval of the majority of workers.

Cis-acting Replication Element Variation of the Foot-and-mouth Disease Virus is Associated with the Determination of Host Susceptibility (구제역바이러스의 숙주 특이성 결정에 연관되어있는 구제역바이러스 cis-acting replication element 변이 분석 연구)

  • Kang, Hyo Rin;Seong, Mi So;Ku, Bok Kyung;Cheong, JaeHun
    • Journal of Life Science
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    • v.30 no.11
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    • pp.947-955
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    • 2020
  • The foot-and-mouth disease virus (FMDV), a member of the Aphthovirus genus in the Picornaviridae family, affects wild and domesticated ruminants and pigs. During replication of the FMDV RNA (ribonucleic acid) genome, FMDV-encoding RNA polymerase 3D acts in a highly location-specific manner. This suggests that specific RNA structures recognized by 3D polymerase within non-coding regions of the FMDV genome assist with binding during replication. One such region is the cis-acting replication element (CRE), which functions as a template for RNA replication. The FMDV CRE adopts a stem-loop conformation with an extended duplex stem, supporting a novel 15-17 nucleotide loop that derives stability from base-stacking interactions, with the exact RNA nucleotide sequence of the CRE producing different RNA secondary structures. Here, we show that CRE sequences of FMDVs isolated in Korea from 2010 to 2017 exhibit A and O genotypes. Interestingly, variations in the RNA secondary structure of the Korean FMDVs are consistent with the phylogenetic relationships between these viruses and reveal the specificity of FMDV infections for particular host species. Therefore, we conclude that each genetic clade of Korean FMDV is characterized by a unique functional CRE and that the evolutionary success of new genetic lineages may be associated with the invention of a novel CRE motif. Therefore, we propose that the specific RNA structure of a CRE is an additional criterion for FMDV classification dependent on the host species. These findings will help correctly analyze CRE sequences and indicate the specificity of host species for future FMDV epidemics.