• Honam Mathematical Journal
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• v.42 no.3
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• pp.511-520
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• 2020

A module M is called cofinitely closed weak δ-supplemented (briefly δ-ccws-module) if for any cofinite closed submodule N of M has a weak δ-supplement in M. In this paper we investigate the basic properties of δ-ccws modules. In the light of this study, we can list the main facts obtained as following: (1) Any cofinite closed direct summand of a δ-ccws module is also a δ-ccws module; (2) Let R be a left δ-V -ring. Then R is a δ-ccws module iff R is a ccws-module iff R is extending; (3) Any nonsingular homomorphic image of a δ-ccws-module is also a δ-ccws-module; (4) We characterize nonsingular δ-V -rings in which all nonsingular modules are δ-ccws.

• Structural Engineering and Mechanics
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• v.66 no.3
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• pp.387-397
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• 2018

In this paper, a general closed-form solution for evaluating the dynamic behavior of a Timoshenko beam on elastic foundation under a moving harmonic line load is formulated in the frequency-wavenumber domain and in a moving coordinate system. It is found that the characteristic equation is quartic with real coefficients only, and its poles can be presented explicitly. This enables the substitution of these poles into Cauchy's residue theorem, leading to the general closed-form solution. The solution can be reduced to seven existing closed-form solutions to different sub-problems and a new closed-form solution to the subproblem of a Timoshenko beam on an elastic foundation subjected to a moving quasi-static line load. Two examples are included to verify the solution.

• Journal of Korean Dental Science
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• v.4 no.2
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• pp.85-91
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• 2011

Some treatment methods have been proposed for patients with chronic closed lock of temporomandibular joint. We report a conservative treatment for patients who had chronic closed lock of temporomandibular joint and who did not want surgical treatment. Two patients who had been treated in the Template clinic, Soonchunhyang University Bucheon Hospital, are the subjects of this report. The subjects had chronic closed lock symptom for over 3 months after an onset of locking; conventional therapies had no effect. The subjects were treated by making them wear a Template appliance while sleeping and exercise for 10 hours a day. After periodic follow-up, significant improvement was observed for Template treatment in terms of the maximal mouth opening range. When conventional therapy is expected to be ineffective, The Template appliance can be used as conservative treatment for temporomandibular disorders patients with chronic closed lock of temporomandibular joint.

• Industrial Engineering and Management Systems
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• v.7 no.1
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• pp.78-89
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• 2008

The need for holistic modeling efforts for returns that capture the extended closed loop supply chain (CLSC) system at strategic as well as operational level has been clearly recognized by the industry and academia. Strategic decision-makers need comprehensive models that can guide them in efficient decision-making to increase the profitability of the entire forward and return chain. Therefore, determination of a near optimal design configuration, which includes the environmental, economical and technological capability factors, is important in strategic decision-making effort that affect the profitability of the closed loop supply chain. In this paper, we adopted an improved system dynamics methodology to tackle strategic issues that affect various performance measures, like market, time/cost, environment etc., for closed loop supply chains. After studying real life implementation issues in CLSC design, we presented guidelines for the PBM (Participative Business Modeling) methodology and presented its extension for the strategic dynamic system modeling of return chains. Finally, we demonstrated the measurement of operational performance by extending SD (system dynamic) application to closed loop supply chain management.

• Korean Journal of Mathematics
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• v.29 no.3
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• pp.493-499
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• 2021

Every closed subset of a compact topological space is compact. Also every compact subset of a Hausdorff topological space is closed. It follows that compact subsets are precisely the closed subsets in a compact Hausdorff space. It is also proved that a topological space is maximal compact if and only if its compact subsets are precisely the closed subsets. A locale is a categorical extension of topological spaces and a frame is an object in its opposite category. We investigate to find whether the closed sublocales are exactly the compact sublocales of a compact Hausdorff frame. We also try to investigate whether the closed sublocales are exactly the compact sublocales of a maximal compact frame.

• PNF and Movement
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• v.10 no.3
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• pp.25-31
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• 2012

Purpose : This study was intended to compare muscle activity in relation to knee joint angles on closed kinetic chain. Methods : A total of 13 subjects consisting of 5 adult males and 8 adult females were made to make movements maintaining knee joint angles at $30^{\circ}$, $45^{\circ}$ and $90^{\circ}$ on closed kinetic chain and the muscle activity occurring in their vastus medialis, rectus femoris and vastus lateralis was measured. Statistical data were analyzed using oneway ANOVA. Results : On closed kinetic chain, the muscle activity of the vastus medialis, rectus femoris and vastus lateralis increased the most at $90^{\circ}$ among the knee joint angles with statistically significant differences(p<0.05). Conclusion : On closed kinetic chain, it could be seen that as the angle of the knee joint increased, the muscle activity increased.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.10a
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• pp.570-571
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• 2021

The research on waste power batteries in China in the past ten years reveals that the power battery recycling industry is enormous but marred with several challenges. A study of China's current power battery closed-loop supply chain revealed some issues in the power battery recycling industry, such as imperfect supply chain, small recycling scale, asymmetric information, and imperfect profit distribution mechanism. This paper uses the theory of corporate social responsibility and consumer choice to propose a closed-loop network of power batteries based on block chain technology and analyzes the existing closed-loop supply chain of power batteries. Consequently, this study provides a new idea for developing the power battery closed-loop supply chain by proposing the closed-loop network of power batteries based on blockchain technology

• Honam Mathematical Journal
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• v.20 no.1
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• pp.15-19
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• 1998

In this note we characterize the radical of a submodule by its invelope under some conditions and prove propositions about closed submodules.

• Honam Mathematical Journal
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• v.33 no.3
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• pp.425-430
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• 2011

In this paper, we find some properties on integrall closed modules.

• Journal of Veterinary Clinics
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• v.33 no.6
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• pp.362-367
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• 2016

The aim of the study was to evaluate ultrasonographic findings, affected age, hematology, blood chemistry and clinical signs according to open or closed cervix in 102 bitches presented for treatment of pyometra. The prevalence of pyometra according to breed was observed in Maltese 22.5%, Yorkshire Terrier 13.7% and Shih Tzu 12.7%. The mean age of dogs was $9.6{\pm}0.3years$, and open cervix pyometra was more prevalent than closed cervix pyometra. Clinical signs included anorexia, vaginal discharge, depression, polyuria/polydipsia, vomiting, and abdominal distension. The concentration of BUN and the activity of ALP in dogs with closed cervix pyometra were significantly higher than those in dogs with open cervix pyometra (p < 0.05). The white blood cell and neutrophils in dogs with closed cervix pyometra were significant higher than those in dogs with open cervix pyometra (p < 0.05). Ultrasonographic findings of the uterus with open or closed cervix pyometra showed variable patterns. The uterine wall was variable in appearance, from thick and irregular to smooth and thin. The uterine wall was thicker in open cervix pyometra than in closed cervix pyometra. The luminal cavity included smaller amount of anechoic fluid in open cervix pyometra than in closed cervix pyometra.