• Korean Journal of Applied Biomechanics
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• v.30 no.4
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• pp.285-291
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• 2020

Objective: Shoes midsole are crucial for reducing impact forces on the lower extremity when someone is running. Previous studies report that the cushioning of running shoes make it possible to use less muscular energies. However, the well cushioned shoes result in energy loss as the shoe midsole is compressed. Cushioning reduces the load on the body, it also results in the use of more muscle energy to create propulsion force. The purpose of this study was to investigate the effect of the difference of shoe hardness & resilience on the running. Method: Shoes midsole are crucial for reducing impact forces on the lower extremity when someone is running. Previous studies report that the cushioning of running shoes make it possible to use less muscular energies. However, the well cushioned shoes result in energy loss as the shoe midsole is compressed. Cushioning reduces the load on the body, it also results in the use of more muscle energy to create propulsion force. The purpose of this study was to investigate the effect of the difference of shoe hardness & resilience on the running. Results: In vastus lateralis muscle Activation, Type 55 were significantly higher for Type 50 and X (p=0.019, p=0.045). In Gluteus Maximus muscle activation, Type 55 was significantly lower for type 50 (p=0.005). In loading late, Type 55 and X were significantly higher for type 45 (p=0.008, p=0.006). Conclusion: The components of a shoe are very complex, and there can be many differences in manufacturing as well. Although some differences can be found in the biomechanical variables of the high elastic midsole, it is difficult to interpret the performance enhancement and injury prevention.

• Journal of Environmental Science International
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• v.27 no.11
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• pp.1023-1028
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• 2018

Shape memory materials are widely used in high-tech industries. Although shape memory polymers have been developed, they have a disadvantage, only unidirectional resilience. Shape memory polymers with bi-directional recovery resilience have been actively studied. In this study, a bidirectional shape memory polyurethane was synthesized using poly(${\varepsilon}$-caprolactone) diol, methylene dicyclohexyl diisocyanate, and hydroxyethyl acrylate. The first physical curing occurred between hard segments and hydrogen bondings when the solution was dried. The second curing in acrylate groups was performed by UV exposure. A degree of curing was analyzed by infrared spectroscopy. The shape memory properties of 2 step-cured polyurethanes were investigated as a function of UV curing time.

• The Journal of the Korea Contents Association
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• v.22 no.2
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• pp.529-544
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• 2022

With the global pandemic in the era of the 4th industrial revolution, the business environment of companies was engulfed by rapid volatility and uncertainty. In particular, in order for an organization to have high competitiveness due to the spread of the flexible work system, relationship management with members of the organization and self-directed job crafting are recognized as important key resources. This study aims to investigate how relational energy and resilience within a corporate organization affect job crafting and to verify the effect of job crafting on individual job performance. For empirical research, 400 valid responses to employees of general companies were analyzed by SPSS 26.0 and Smart PLS 3.0. As a result of the analysis, first, it was confirmed that relational energy did not have a positive (+) effect on task crafting. Second, it was found that relational energy had a positive (+) effect on relational crafting and cognitive crafting, respectively. Third, it was found that resilience had a positive (+) effect on both task crafting, relationship crafting, and cognitive crafting that constitute job crafting. Fourth, it was found that job crafting had a positive (+) effect on individual job performance. Based on these research results, we intend to derive academic and practical implications and provide practical help to follow-up researchers and stakeholders.

• Journal of the Korean Society of Industry Convergence
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• v.9 no.4
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• pp.337-341
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• 2006

The tensile properties of Poly(trimethylene terephthalate, PTT) $1{\times}1Rib$ knitted fabrics were experimentally studies, and the specimens has $1{\times}1$ rib stitched structure which are weft knitted fabrics with various lengths of loop. The $1{\times}1$ rib weft knitted fabric showed larger tensile linearity, tensile energy and tensile resilience in the direction of courses. The tensile properties increased with increasing the loop density in all directions, and perfectly increased with the course directions than the wale directions.

• Textile Coloration and Finishing
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• v.12 no.1
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• pp.17-24
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• 2000

The tensile properties of polyester warp knitted fabrics of satin and reverse satin structure with various lengths of underlap were studied. In the range of low tension, the satin warp knitted fabric showed larger tensile energy and elongation in the direction of $0^\circ$ and larger tensile linearity, tensile resilience and initial modulus in $90^\circ$. Meanwhile, reverse satin one showed larger initial moduli in 0$^{\circ}$ and larger the others in $90^\circ$. In the range of high tension, the tendencies of both fabrics in $0^\circ$ direction were almost the same as those in all direction. As the under laps were shorter for both fabrics, tensile linearity, tensile energy and elongation increased, but tensile resilience decreased in all directions. However initial moduli were changed little.

• ETRI Journal
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• v.38 no.5
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• pp.911-921
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• 2016

This paper presents the description, practical implementation, and stability analysis of a recently proposed, energy-efficient, medium access control protocol for wireless sensor networks, ALOHA-Q, which employs a reinforcement-learning framework as an intelligent transmission strategy. The channel performance is evaluated through a simulation and experiments conducted using a real-world test-bed. The stability of the system against possible changes in the environment and changing channel conditions is studied with a discussion on the resilience level of the system. A Markov model is derived to represent the system behavior and estimate the time in which the system loses its operation. A novel scheme is also proposed to protect the lifetime of the system when the environment and channel conditions do not sufficiently maintain the system operation.

• Earthquakes and Structures
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• v.18 no.1
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• pp.129-145
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• 2020

Seismic resilience is a key feature for buildings that play a strategic role within the community. In this framework, not only the structural and non-structural elements damage but also the protracted structural dysfunction can contribute significantly to overall seismic damage and post-seismic crisis situations. Reduction of the residual and peak displacements and energy dissipation by replaceable elements are some effective aspects to pursue in order to enhance the resilience. Control systems able to adapt their response based on the nature of events, such as active or semi-active, can achieve the best results, but also require higher costs and their complexity jeopardizes their reliability; on the other hand, a passive control system is not able to adapt but its functioning is more reliable and characterized by lower costs. In this study it is proposed a strategy for the optimization of the dissipative capacity of a seismic resistant system obtained placing in parallel two different groups dissipative Re-Centering Devices, specifically designed to enhance the energy dissipation, one for the low and the other for the high intensity earthquakes. In this way the efficiency of the system in dissipating the seismic energy is kept less sensitive to the seismic intensity compared to the case of only one group of dissipative devices.

• Korean small business review
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• v.43 no.2
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• pp.1-30
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• 2021

This study is to analyze the relationship between supply chain resilience antecedent factors, supply chain resilience and business performance. Supply chain integration, risk management activity, and visibility were selected as the preceding factors of supply chain resilience, and the effect of these factors on agility and robustness as supply chain resilience, and the effects of agility and robustness factors on corporate management performance are studied. To this end, a survey was conducted on Korean manufacturing companies, and a total of 124 questionnaires were used for the study. As a result of the testing of the research hypothesis, supply chain integration, risk management activity, and visibility have a positive (+) significant effect on agility and robustness. In addition, agility had a positive (+) effect on corporate management performance. But robustness had a positive (+) effect on corporate management performance, but not significant. In order for manufacturing companies to secure supply chain resilience through such research hypothesis testing, it is necessary to secure supply chain integration, risk management activity, and visibility capabilities. It was confirmed that agility and visibility capability can be linked to corporate management performance. In addition, the overall relationship structure between the preceding factors of supply chain resilience, supply chain resilience, and business performance was presented.

• Elastomers and Composites
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• v.45 no.4
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• pp.309-315
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• 2010

The CIIR blends, which is use for shoes outsole, with SSBR, XNBR and KBR were prepared with various mixing ratio. The viscoelastic properties of these blends, such as tensile modulus, rebound resilience, storage modulus, tan${\delta}$, and creep properties were measured. In the rebound resilience measurement, KBR showed the highest value, which means the lowest energy absorption to stress. As SSBR, XNBR and KBR blends with CIIR, the rebound resilience of the mixtures showed tendency to increase in arithmetic average. In the creep measurement, CIIR showed the highest visconse strain to stress, SSBR and KBR showed lower visconse strain. Maximum tan${\delta}$ peak of CIIR, SSBR and XNBR appeared at $-30^{\circ}C$, $5^{\circ}C$ and $0^{\circ}C$ respectively.

• Human Ecology Research
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• v.55 no.4
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• pp.441-450
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• 2017

Childcare related studies have focused on the characteristics of care work, policy aspects, user family satisfaction, and job satisfaction of childcare helpers. But there have been few studies on family system characteristics that support childcare givers. Thus, this study conducted on the topic, "How to characterize the family resilience of long-term childcare givers?" The subjects belong to a healthy family support center in U. City, who belong to a group with an income in the top 20 % of about 20 persons working for more than 3 years. In an interview, qualitative questions were used Walsh's family resilience. The results are as follows. First, they had economic hardship, but their family would stand together and build up a family's power based on the couple's faith. They had a family role model based on their parents' family that included inherited maternity qualities from their mother. Second, the flexibility of the family organization changed to autonomous or co-role type and the connectivity. Especially, they appear as a family's leader. Third, their family communication was active, shared-care, responsible and passionate with family affection and understanding. The conclusions results are as follows. Participants were high school graduates as well as had work experience. They were characterized by positive family energy, a family belief system, family-based resources, flexibility, connectivity, open family communication and expression skills. Therefore, it can be suggested that it is necessary to check the family's resilience during an interview for the reliable, long-term supply of human resources for childcare activities.