• Title/Summary/Keyword: Data rigidity

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The determination of effect of TiO2 on dynamic behavior of scaled WPC warehouse by OMA

  • Tuhta, Sertac
    • Advances in nano research
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    • v.12 no.1
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    • pp.65-72
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    • 2022
  • The dynamic properties (frequencies, mode shapes, damping ratios) of the scaled WPC warehouse are compared using the operational modal analysis approach to the dynamic parameters (frequencies, mode shapes, damping ratios) of the full outer surface of titanium dioxide, 70 micron in thickness. Micro tremor ambient vibration data on ground level was used to provide ambient excitation. For the output-only modal identification, Enhanced Frequency Domain Decomposition (EFDD) was used. This study discovered a strong correlation between mode shapes. Titanium dioxide applied to the entire outer surface of the scaled WPC warehouse results in an average 14.05 percent difference in frequency values and 7.61 percent difference in damping ratios, demonstrating that nanomaterials can be used to increase rigidity in structures, or for reinforcement. Another significant finding in the study was the highest level of adherence of titanium dioxide and similar nanomaterials mentioned in the introduction to WPC structure surfaces.

Mechanical and elastic properties of vitrified radioactive wastes using ultrasonic technique

  • Sema Akyil Erenturk;Filiz Gur;Mahmoud A.A. Aslani
    • Nuclear Engineering and Technology
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    • v.56 no.2
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    • pp.472-476
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    • 2024
  • It is important that radioactive and nuclear wastes are immobilized in a glass composition with lower melting temperatures due to their economy. In this study, the elastic and mechanical properties of sodium borate-based vitrified radioactive waste were measured using ultrasonic techniques. Many ultrasonic parameters, such as elastic moduli, Poisson's ratio, and microhardness, were calculated by measuring the ultrasonic velocities of the glasses. The ultrasonic velocity data, the density, the calculated elastic moduli, micro-hardness, softening temperature, and Debye temperature depending on the glass composition were evaluated, and the relation with the structure was clarified. It was observed that the elastic modulus and Poisson ratio increased as the Cs2O content increased in glasses containing Cs waste. This result shows that the rigidity of the network structure of these glasses increases in contrast to the glass containing Sr.

Semi-rigidity of cap plate and extended end plate connections

  • Nassani, Dia Eddin;Chikho, Abdul Hakim;Akgonen, Aliriza llker
    • Steel and Composite Structures
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    • v.23 no.5
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    • pp.493-499
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    • 2017
  • The behaviour of steel frames is highly influenced by the beam-column connections. Traditionally, Steel frames were usually designed assuming that connections are ideally pinned or fully rigid. A semi-rigid connection, however, creates a balance between the two extreme approaches mentioned above. In this research, two full scales of Extended End Plate Connections (EEPCs) were tested. Mathematical and numerical models were used to analyse the connections, and close correlations were found between these models and the corresponding tested specimens, which confirmed the confidence in the experimental results. The experimental results obtained enrich the available test data about behaviour of EEPC. In addition, the purpose of studying EEPC experimentally is to compare the stiffness and moment-rotation curve of EEPCs with that of Cap Plate Connections (CPCs), which were tested in a previous work. CPCs have not been studied sufficiently in the literature. The results obtained show that the typical CPC reduces the connection stiffness and these results will make a valuable contribution to the available test data in the research area of CPC.

Reliability and Validity of Korean Version of the Child Abuse Potential Inventory (한국어판 아동학대 잠재성 도구의 신뢰도와 타당도 검증)

  • Lee, Sona;Ahn, Hye Young
    • Child Health Nursing Research
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    • v.25 no.2
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    • pp.85-94
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    • 2019
  • Purpose: This study presents methodological research that aimed to verify the content validity, construct validity, reliability, and criterion-related validity of the Child Abuse Potential Inventory (CAPI), originally developed by Milner and then translated into Korean by Ahn. Methods: Data used in this study were collected from 209 mothers of infants, toddlers, and children of preschool age in D metropolitan city. The collected data were analyzed using SPSS version 24. Results: The Korean version of the Child Abuse Potential Inventory (K-CAPI) was developed by condensing 44 of the original 77 CAPI items. Four factors of K-CAPI were extracted using principal component analysis. These 4 factors-distress; problems with child, self, family, and others; unhappiness; rigidity-accounted for 54.01% of variance. The Cronbach's ${\alpha}$ was .96, the Guttman split-half coefficient was .88, and test-retest reliability was r=.86 (p<.001). Conclusion: The results of this study established the reliability and validity of the K-CAPI and found it to be an appropriate tool to evaluate mothers' potential to abuse their children.

Effects of Stretching Exercise Included Health Education on Physical Health Index, Self-reported Symptoms, and Self-efficacy of Exercise in Elderly (건강교육을 포함한 신장운동이 노인의 생리적인 지표와 자가증상 보고 및 운동 자기효능에 미치는 효과)

  • Kim, Kwuy-Bun;Han, Sang-Sook;Won, Jeoung-Sook;Kim, Won-Ok;Hyun, Kyung-Sun
    • Journal of East-West Nursing Research
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    • v.9 no.1
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    • pp.25-34
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    • 2004
  • This was one experimental study, conducted to identify the effects of stretching exercise included health education on physical health index, self-reported symptoms, and self-efficacy of exercise in Elderly. Subjects included 28 women elderly who were residents of H Dong, Dondae moon-Gu, Seoul. The treatment intervention was applied during total 8 weeks as 5 times/week for stretching exercise with 2 times/weeks for health education. Data collection were from February to April, 2004. SPSS Window program was used by aims of this study for data analysis. The results were as following: 1. 75 old age above (39.3%) was the most of age in subjects. None education (42.9%) was the most of subjects in this study. Perceived health state was the most as 71.4% in moderate and good health state. 2. Stretching exercise included health education, significantly effected on the total Cholesterol, HDL-cholesterol, triglyceride (p=.009*; p=.043*; p=.006*). However, the body fat weight was no significantly on the effect of stretching exercise included health education (p=.991). Also, stretching exercise included health education, significantly effected on total self-reported symptoms (p=.001*) with joint pain, joint rigidity, fatigue, indigestion, elimination disorder, and sleep disturbance. However, indigestion (p=.129) was no significantly on the effect of stretching exercise included health education. Self efficacy of exercise (p=.000*) was significantly on the effect. As according to this results, physical health index (total Cholesterol, HDL-cholesterol, triglyceride) and self-reported symptoms (joint pain, joint rigidity, fatigue, elimination disorder, and sleep disturbance) were reduced through stretching exercise included health education. Self efficacy was improved by this exercise program. Therefore, it is confirmed that stretching exercise included health education is an effective nursing intervention for physical, mental, and psychological health management in elderly. Accordingly, authors are proposing that variously effective health management exercise programs must be developed for elderly, at the same time, the application and following up on the programs will be more important in the future.

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OMA of model steel structure retrofitted with CFRP using earthquake simulator

  • Kasimzade, Azer A.;Tuhta, Sertac
    • Earthquakes and Structures
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    • v.12 no.6
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    • pp.689-697
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    • 2017
  • Nowadays, there are a great number of various structures that have been retrofitted by using different FRP Composites. Due to this, more researches need to be conducted to know more the characteristics of these structures, not only that but also a comparison among them before and after the retrofitting is needed. In this research, a model steel structure is tested using a bench-scale earthquake simulator on the shake table, using recorded micro tremor data, in order to get the dynamic behaviors. Beams of the model steel structure are then retrofitted by using CFRP composite, and then tested on the Quanser shake table by using the recorded micro tremor data. At this stage, it is needed to evaluate the dynamic behaviors of the retrofitted model steel structure. Various types of methods of OMA, such as EFDD, SSI, etc. are used to take action in the ambient responses. Having a purpose to learn more about the effects of FRP composite, experimental model analysis of both types (retrofitted and no-retrofitted models) is conducted to evaluate their dynamic behaviors. There is a provision of ambient excitation to the shake table by using recorded micro tremor ambient vibration data on ground level. Furthermore, the Enhanced Frequency Domain decomposition is used through output-only modal identification. At the end of this study, moderate correlation is obtained between mode shapes, periods and damping ratios. The aim of this research is to show and determine the effects of CFRP Composite implementation on structural responses of the model steel structure, in terms of changing its dynamical behaviors. The frequencies for model steel structure and the retrofitted model steel structure are shown to be 34.43% in average difference. Finally, it is shown that, in order to evaluate the period and rigidity of retrofitted structures, OMA might be used.

GFRP retrofitting effect on the dynamic characteristics of model steel structure

  • Tuhta, Sertac
    • Steel and Composite Structures
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    • v.28 no.2
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    • pp.223-231
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    • 2018
  • Nowadays, there are a great number of various structures that have been retrofitted by using different FRP Composites. Due to this, more researches need to be conducted to know more the characteristics of these structures, not only that but also a comparison among them before and after the retrofitting is needed. In this research, a model steel structure is tested using a bench-scale earthquake simulator on the shake table, using recorded micro tremor data, in order to get the dynamic behaviors. Columns of the model steel structure are then retrofitted by using GFRP composite, and then tested on the Quanser shake table by using the recorded micro tremor data. At this stage, it is needed to evaluate the dynamic behaviors of the retrofitted model steel structure. Various types of methods of OMA, such as EFDD, SSI, etc. are used to take action in the ambient responses. Having a purpose to learn more about the effects of GFRP composite, experimental model analysis of both types (retrofitted and no-retrofitted models) is conducted to evaluate their dynamic behaviors. There is a provision of ambient excitation to the shake table by using recorded micro tremor ambient vibration data on ground level. Furthermore, the Enhanced Frequency Domain Decomposition is used through output-only modal identification. At the end of this study, moderate correlation is obtained between mode shapes, periods and damping ratios. The aim of this research is to show and determine the effects of GFRP Composite implementation on structural responses of the model steel structure, in terms of changing its dynamical behaviors. The frequencies for model steel structure and the retrofitted model steel structure are shown to be 33.916% in average difference. Finally, it is shown that, in order to evaluate the period and rigidity of retrofitted structures, OMA might be used.

Efficient Load Balancing Technique through Server Load Threshold Alert in SDN (SDN 환경에서의 서버 부하 임계치 경고를 통한 효율적인 부하분산 기법)

  • Lee, Jun-Young;Kwon, Tea-Wook
    • The Journal of the Korea institute of electronic communication sciences
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    • v.16 no.5
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    • pp.817-824
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    • 2021
  • The SDN(Software Defined Networking) technology, which appeared to overcome the limitations of the existing network system, resolves the rigidity of the existing system through the separation of HW and SW in network equipment. These characteristics of SDN provide wide scalability beyond hardware-oriented network equipment, and provide flexible load balancing policies in data centers of various sizes. In the meantime, many studies have been conducted to apply the advantages of SDN to data centers and have shown their effectiveness. The method mainly used in previous studies was to periodically check the server load and perform load balancing based on this. In this method, the more the number of servers and the shorter the server load check cycle, the more traffic increases. In this paper, we propose a new load balancing technique that can eliminate unnecessary traffic and manage server resources more efficiently by reporting to the controller when a specific level of load occurs in the server to solve this limitation.

A Comparative Study between First Attack and Reattack Groups in C.V.A (중풍환자의 초발군과 재발군에 관한 임상적 고찰)

  • 박숙자;권정남;김영균
    • The Journal of Korean Medicine
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    • v.23 no.3
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    • pp.119-133
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    • 2002
  • Objectives : This study was designed to investigate significant differences between the first attack and reattack groups to form fundamental data for decreasing recurrence and secondary prevention of stroke. Methods : I studied 204 patients admitted within 7 days of onset, after the diagnosis of stroke, in the Oriental Medical Hospital of Dongeui University from February to July in 2001.compared the reattack group with the first attack group for risk factors, clinical symptoms and progress, average mark and degree of improvement in Activity Index. Results : 1. Meaningful risk factors associated with the reattack group were male sex, a past history of hypertension and transient ischemic attack, and a family history of stroke. 2. The reattack group had conscious or cognitive disorder in early stage of onset, dysphagia, constipation, urinary incontinence, visual field defect in acute stage, high blood pressure and tachycardia in abnormalvital sign in acute stage, neuropsychosis, shoulder pain and rigidity, and pneumonia in complications more than the first attack group. 3. In Activity Index, the average mark of reattack group was lower than that of the first stroke group and improvement of the reattack group was delayed compared with the first attack group. Conclusions : The reattack group had more severe symptoms and clinical progress than the first attack group.

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Development of Finite Element Analysis Program for the Concrete Pavement (유한 요소법에 의한 콘크리트 포장도로의 구조해석 프로그램개발)

  • 조병완
    • Computational Structural Engineering
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    • v.3 no.2
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    • pp.89-95
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    • 1990
  • As modern industry go further, a rigid concrete pavement has been widely constructed. The load carrying capacity of the flexible asphalt pavements is brought about by a layered system, distributing the load over the subgrade, rather than by the bending action of the slab. On the other hand, the rigid pavement, because of its rigidity and high modulus of elasticity, tends to distribute the traffic load over wide subbases, and its capacity of the strength is supplied by the slab itself. Thus, it is necessary to study the structural behavior of concrete slab under the variations of temperature changes and applied traffic loads. It reguires the development of finite element analysis program for the concrete highway pavement, which provides better understanding of concrete pavement behavior and effective design data to highway engineers.

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