• Smart Structures and Systems
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• 제5권3호
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• pp.291-316
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• 2009

Damage detection using structural classical deflection flexibility has received considerable attention due to the unique features of the flexibility in the last two decades. However, for relatively complex structures, most methods based on classical deflection flexibility fail to locate damage sites to the exact members. In this study, for structures whose members are dominated by axial forces, such as truss structures, a more feasible flexibility for damage detection is proposed, which is called the Axial Strain (AS) flexibility. It is synthesized from measured modal frequencies and axial strain mode shapes which are expressed in terms of translational mode shapes. A damage indicator based on AS flexibility is proposed. In addition, how to integrate the AS flexibility into the Damage Location Vector (DLV) approach (Bernal and Gunes 2004) to improve its performance of damage localization is presented. The methods based on AS flexbility localize multiple damages to the exact members and they are suitable for the cases where the baseline data of the intact structure is not available. The proposed methods are demonstrated by numerical simulations of a 14-bay planar truss and a five-story steel frame and experiments on a five-story steel frame.

• Structural Engineering and Mechanics
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• 제77권4호
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• pp.463-472
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• 2021

Fully rigid floor diaphragm is one of the main assumptions that are widely used in common practices due to its simple application. However, determining the exact degree of diaphragms flexibility cannot be easily accomplished without finite element modeling, which is an expensive and time-consuming procedure. Therefore, it is always possible that apparently rigid diaphragms, based on prescriptive limitations of seismic codes, experience some degrees of flexibility during the earthquakes. Since diaphragm flexibility has more uncertainties in asymmetric-plan structures, this study focuses on errors resulting from probable floor diaphragm flexibility of torsionally restrained structures. The analytical models used in this study were single-story buildings with asymmetric plan and RC shear walls. Although floor system is not considered explicitly, a wide range of considered diaphragm flexibility, from fully rigid to quite flexible, allows the results to be generalizable to a lot of lateral load resisting systems as well as floor systems. It has been shown that in addition to previously known effects of diaphragm flexibility, presence of orthogonal side elements during design procedure with rigid diaphragm assumption and rapid reduction in their absorbed forces can also be an important source to increase errors due to flexibility. Accordingly, from the obtained results the authors suggest designers to consider the possibility of diaphragm flexibility and its adverse effects, especially in torsionally restrained systems in their common designs.

• 경영과정보연구
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• 제30권4호
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• pp.475-509
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• 2011

본 연구는 우리나라 195개의 기업을 대상으로 세계적으로 관심의 대상이 되고 있는 노동시장의 유연성 전략 즉 수량적 유연성과 기능적 유연성이 조직의 결과변수인 생산성, 노사협력성, 고용안정 등에 어떠한 영향을 주는가를 기업 단위로 분석하였다. 또한 노동시장 유연성(수량적 유연성 및 기능적 유연성)과 노사협력성 및 고용안정간의 관계에서 노조 힘의 조절역할에 대해서도 분석하였다. 결과는 수량적 유연성은 생산성, 노사협력성, 고용안정 등과 유의한 관계를 보여주지 않았으나 기능적 유연성은 생산성, 노사협력성, 고용안정 등에 상당한 정의관계를 보여 주었다. 이러한 결과는 기업의 노동시장 전략에서 기능적 유연성의 중요성을 다시 확인할 수 있다. 서구에서는 기능적 유연성의 중요성을 지속적으로 주장하고 수량적 유연성의 문제점을 지적하고 있다. 그러나 본 연구에서는 기능적 유연성의 긍정적 측면은 확인이 되었으나 수량적 유연성의 부정적 관계가 확인될 수 없었다는 점에서 이들 관계는 앞으로 좀 더 연구가 지속되어야 하는 과제도 남겼다. 노동시장 유연성과 노사협력 및 고용안정과의 관계에서 노조 힘의 조절역할에 대한 분석결과는 수량적 유연성과 노사협력성 관계에서만 노조 힘의 상호작용 효과가 확인되었다. 이러한 결과는 노조의 기회주의적 행동에 대한 가능성을 엿볼 수 있다. 이러한 결과에 대한 논의를 할 것이다.

• Structural Engineering and Mechanics
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• 제13권4호
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• pp.437-453
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• 2002

In this paper, dynamic stiffness and flexibility for circular membranes are analytically derived using an efficient mixed-part dual boundary element method (BEM). We employ three approaches, the complex-valued BEM, the real-part and imaginary-part BEM, to determine the dynamic stiffness and flexibility. In the analytical formulation, the continuous system for a circular membrane is transformed into a discrete system with a circulant matrix. Based on the properties of the circulant, the analytical solutions for the dynamic stiffness and flexibility are derived. In deriving the stiffness and flexibility, the spurious resonance is cancelled out. Numerical aspects are discussed and emphasized. The problem of numerical instability due to division by zero is avoided by choosing additional constraints from the information of real and imaginary parts in the dual formulation. For the overdetermined system, the least squares method is considered to determine the dynamic stiffness and flexibility. A general purpose program has been developed to test several examples including circular and square cases.

• 대한통합의학회지
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• 제5권1호
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• pp.35-42
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• 2017

Purpose : This study examined the symptoms and body flexibility according to physical change of the female college students who like to wear skinny jeans. Methods : This study targeted 39 female college students and conducted a questionnaire survey on physical change and disease, and measured waist flexibility and hip joint working range. Result : The study subjects showed much fatigue, subjective symptoms, and the highest varicose veins. As for comparison before and after waist flexibility measurement, the mean value of the waist flexibility was 17.97 before the experiment, and the mean value after the experiment was 17.63. Therefore there was a significant difference (P<.5). Conclusion : As a result of this study, the female college students revealed fatigue, varicose veins, and numbness, as well as waist flexibility and hip joint limitations even with a little walk.

• The Journal of Korean Physical Therapy
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• 제17권4호
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• pp.477-484
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• 2005

Purpose: The purpose of this study was to evaluate effect of Thera-Band stretching exercise on flexibility of shoulder joint. Methods: The research deign was a experimental pre-post control group design. Sixteen subject were randomly divided into two groups; experimental group(n=8) and control group(n=8). Experimental group performed Thera-Band PNF stretching for 4 weeks and control group was not performed. To compare with the effectiveness of Thera-Band PNF stretching between two groups, I measured flexibility of shoulder joint with an Apley scratch test. The data were analyzed by Independence T-test. Results: The experimental group was significantly increased the flexibility at the right and left shoulder internal rotation. But the experimental group was not significantly increased the flexibility at the right and left shoulder external rotation. Conclusion: These result suggest that home-based exercise programs with Thera-Band can serve as a practical and effective means of flexibility gains in general people.

• 디지털융복합연구
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• 제10권11호
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• pp.165-174
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• 2012

본 연구는 스마트워크 도입의 활성화를 위해 스마트워크의 시간유연성, 공간유연성, 자원유연성, ICT 인프라 속성이 스마트워크 이용의도에 미치는 영향을 분석하였다. 이러한 영향을 지역의 제조업을 대상으로 직군, 기업규모에 따른 스마트워크의 유형 선호도를 중심으로 분석한 결과 스마트워크 도입초기에 나타날 수 있는 ICT인프라의 영향이 가장 높게 나타났으며, 기존의 스마트워크에서 강조되어온 시간과 공간의 유연성은 낮은 반면에 자원의 유연성이 상대적으로 높게 나타났다. 이러한 결과는 스마트워크의 도입 전 대면중심의 수직적 조직문화에서 성과중심의 수평적 조직문화로의 변화와 집단지성과 협력을 통한 조직문화로의 변화를 인식함으로써 제조업의 구성원 모두에게 만족을 줄 수 있는 스마트워킹의 성공가능성을 제시하고 있다.

• 대한물리의학회지
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• 제14권4호
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• pp.183-193
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• 2019

PURPOSE: This study assessed the exercise programs for improving the spinal angle and trunk flexibility by applying the aquatic exercise and sling exercise to young adults with scoliosis. METHODS: The subjects were 14 participants diagnosed with scoliosis. They were assigned randomly either to an aquatic exercise group (n=7) that received the WATSU exercise program or to a sling exercise group (n=7) that received a sling exercise program. The exercise program was 50 minutes once, three times a week, 12 times for four weeks. The spinal angle and flexibility were measured using the Cobb's angle and modified sit and reach test, respectively. Two variables were analyzed before and after the intervention, and the aquatic exercise group and sling exercise group were compared. RESULTS: After the intervention, the Cobb's angle decreased significantly, and the flexibility increased significantly in both groups (p<.05). A larger increase in flexibility was observed in the aquatic exercise group than in the sling exercise group (p<.05). CONCLUSION: These results showed that the two exercise programs improved the spine angle and flexibility. The increased flexibility showed that aquatic exercise was more effective than the sling exercise. Therefore, aquatic exercise and sling exercise can be used in the treatment and prevention of scoliosis.

• Industrial Engineering and Management Systems
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• 제14권3호
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• pp.236-247
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• 2015

This study aims to examine the effects of industrial clustering and manufacturing flexibility on innovation capability and operational performance. This study follow a survey method to collect data pertaining to the phenomena of industrial clustering, manufacturing flexibility, innovation capability, and operational performance by utilizing a single respondent design. A total of 124 Indonesian manufacturing SMEs are taken to test the proposed theoretical model by utilizing covariance-based structural equations modeling approach. It was found that both industrial clustering and manufacturing flexibility was positively associated with operational performance and innovation capability as well. In addition, innovation capability may account for the effects of industrial clustering and manufacturing flexibility on operational performance. This implies that manufacturing SMEs have to reorient their production and operation perspectives, including agglomerate with other similar or related SMEs to develop and utilize their own resources. The SMEs also need to possess some degree of manufacturing flexibility in respond to the uncertain environment and market changes. In addition, the SMEs should put a greater emphasize to use industrial cluster and manufacturing flexibility benefits to generate innovation capability to achieve high performance.

• 대한물리의학회지
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• 제11권3호
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• pp.1-9
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• 2016

PURPOSE: The purpose of this study was to identify the effects on flexibility of bridge and plank exercises using sling suspension on an unstable surface. METHODS: The subjects of this study were 20 healthy adults in their 20s (plank=10, bridge=10). Both types of exercise were performed three times per week for a period of four weeks. Each exercise was performed in the front and side direction. Exercise intensity was altered through the use of a sling, which was placed at the knee and ankle. Flexibility at trunk forward flexion and backward extension was measured. The trunk forward flexion was measured at sitting position. The trunk backward extension was measured at prone position. The data were analyzed by Two-way ANOVA. RESULTS: There were significant differences in the pre- and post-test for both the bridge and plank exercise groups. In the bridge exercise, significant differences were shown in the trunk forward flexion and the trunk backward extension (p<.05). In the plank exercise, a significant difference was shown in the trunk backward extension (p<.05). No significant differences were noted in interaction effect or the main effects in either group. CONCLUSION: Bridge and plank exercises on an unstable surface improve flexibility. The bridge exercise improves the flexibility of the forward and backward muscles of the trunk. The plank exercise improves the flexibility of the forward muscles of the trunk. This information would be useful in the development of exercise programs including bridge and plank exercises for improving flexibility and core stability.