• East Asian mathematical journal
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• v.25 no.4
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• pp.441-447
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• 2009

Jat and Choudhari defined a near-ring R with left bipotent or right bipotent condition in 1979. Also, we can dene a near-ring R as subcommutative if aR = Ra for all a in R. From these above two concepts it is natural to investigate the near-ring R with the properties aR = $Ra^2$ (resp. $a^2R$ = Ra) for each a in R. We will say that such is a near-ring with (1,2)-potent condition (resp. a near-ring with (2,1)-potent condition). Thus, we can extend a general concept of a near-ring R with (m,n)-potent condition, that is, $a^mR\;=\;Ra^n$ for each a in R, where m, n are positive integers. We will derive properties of near-ring with (1,n) and (n,1)-potent conditions where n is a positive integer, any homomorphic image of (m,n)-potent near-ring is also (m,n)-potent, and we will obtain some characterization of regular near-rings with (m,n)-potent conditions.

• Physical Therapy Korea
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• v.13 no.4
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• pp.30-38
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• 2006

This study was to investigate the influence of cooling on muscle force and viscoelastic properties of tendon structures in themedial gastrocnemius (MG) muscle. The subject was instructed to gradually increase force (10% MVC step) from a relaxed state to MVC within 3 s. At this time, it was measured by an ultrasonographic probe was attached and that an electrode was attached to monitor EMG. The F values at 50 100% of MVC were significantly greater under the cold condition than under the non-cold condition (p<.05). The ${\Delta}F/{\Delta}L$ values at 80~100% of MVC were significantly higher under the cold condition than under the non-cold condition (p<.05). The elongation under the non-cold condition had a tendency to be greater than that under the cold condition. The results suggest that cooling results in an increase in the stiffness of tendon structures with a reduction of muscle force and elongation.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1062-1067
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• 2003

In this study, corrosion fatigue characteristics of CF8M and CF8A steel were investigated on the simulated PWR condition(Temp.:$316^{\circ}C$, Pres.: 15:MPa). To make the simulated PWR condition. the special test machine consisted of INSTRON, Autoclave, LOOP and Measurement system was developed. As ${\Delta}K$ is ranged from 11 to $20MPa{\sqrt{m}}$, Crack growth rate of PWR condition is faster than air condition. Above $20MPa{\sqrt{m}}$, the crack growth rate of PWR and air condition is similar. Corrosion fatigue characteristics regardless of the ferrite contents($10{\sim}25wt.%$) is not different. After the test, the fracture surface of specimens was examined. It was difficult to verify the fracture modes such as striation, intergranular crack and cleavage and so on. As the ferrite content of CF8M is increased, the more particles covered fracture surface were peeled.

• Earthquakes and Structures
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• v.9 no.4
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• pp.767-788
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• 2015

A steel shear wall with double-tapered links and in-plane reference was developed for assisting the assessment of the structural condition of a building after an earthquake while maintaining the original role of the wall as a passive damper device. The double-tapered link subjected to in-plane shear deformation is designed to deform torsionally after the onset of local buckling and works as an indicator of the maximum shear deformation sustained by the shear wall during an earthquake. This paper first examines the effectiveness of double-tapered links in the assessment of the structural condition under various types of loading. A design procedure using a baseline incremental two-cycle loading protocol is verified numerically and experimentally. Meanwhile, in-plane reference links are introduced to double-tapered links and greatly enhance objectivity in the inspection of notable torsional deformation with the naked eye. Finally, a double-layer system, which consists of a layer with double-tapered links and a layer with rectangular links made of low-yield-point steel, is tested to demonstrate the feasibility of realizing both structural condition assessment and enhanced energy dissipation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.469-472
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• 2003

The nematic liquid crystal (NLC) aligning capabilities using a-C:H thin film deposited at the three kinds of rf bias condition were investigated. A high pretilt angle of about $11^{\circ}$ by the ion beam alignment method was observed on the a-C:H thin film (polymer-like carbon) deposited at 1W rf bias condition, and the low pretilt angle of the NLC was observed on the a-C:H thin film(diamond-like carbon) deposited at rf 30W and 60W bias condition. Consequently, the high NLC pretilt angle and the good aligning capabilities of LC alignment by the IB alignment method on the a-C:H thin film deposited at 1W rf bisa condition can be achieved.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.1167-1170
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• 1999

We consider a negative unity feedback control system in which a controller and a given minimum phase transfer function are in cascade. This paper present a sufficient condition for the existence of a constant gain controller under which the overall closed loop characteristic polynomial is stable. This sufficient condition is based on Lehnigk's lemmas.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.124-132
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• 2010

To predict and analyze the rolling stock's fire growth is considered not only important factor in estimating hazard analysis of rolling stock, but also a primary factor in aspect of a rail load facility. Because it's could be regarded as a ignition source in risk assesment for the facility i.e. tunnel and station. However, currently, standardized method to predict and analyze the fire growth has not been completed yet. it is due to the fact that fire growth is not only depended on thermal property of interior materials, but also is affected dominantly by various factors such as ignition source (characterized by location, duration, and intensity), train running condition and in/exterior ventilation condition. Especially, ventilation condition is one of the most effective factor to affect fire growth in compartment space as noticed by under-ventilation fire condition. In this study, the effect of each ventilation condition on fire growth and load were examined through the numerical method through FDS (Fire Dynamics Simulator).

• Journal of Korean Society for Quality Management
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• v.49 no.3
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• pp.269-279
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• 2021

Purpose: The purpose of this study was to suggest weapon system specifications for requirements of Condition-Based Maintenance(CBM/CBM⁺). Methods: The military documents and case studies with regard to condition-based maintenance were reviewed. Representative Korea defense specifications of weapon system such as an aircraft, a C4ISR etc. were analyzed and investigated the level of requirement for maintainability was. Results: Condition-based maintenance was defined in both U.S. instruction and Korean directive. While deparment of defense(U.S.) provide a guidebook for CBM⁺, detailed instruction was not sufficient for Korean. Ministry of national defense(ROK) define the CBM⁺ by means of IPS element which should be developed along with the system development. The maintainability was barely included in Korean defense specifications, except for BIT(Built-in test) function. As a first step for defining the condition-based maintenance requirement in defense specification, this study suggests a standard form for data needed to acquire according to types of system, fault, failure, and so on. Conclusion: The empirical researches on CMB/CBM⁺ with domestic weapon systems are not enough, and a logic which leads the maintenance strategy to CMB/CBM⁺ is not solved. Through technical researches and institutional improvements including this study, we hope that condition-based maintenance would be fully established in the Korean defense field.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.4
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• pp.57-67
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• 2014

The vigor condition of trees is an important indicator for the management of urban forested area. But difficulties in how to assess the tree vigor condition still remain. Previous efforts were limited in the 1) measurement of single indicator rather than using multiple indices, 2) purpose-oriented measurement such as for air-pollution effect or specific pathological symptom, and 3) ordinal-scale evaluations by field crews 4) despite human errors based on his/her experiences or prior knowledge. Therefore, this study attempted to develop a quantitative and objective methodology for assessing tree vigor condition, by measuring multiple modules and building the profile inventory. Furthermore, the possibility and limitations were discussed in terms of schematic frames describing tree vigor condition. The vigor condition of 56 flowering cherry plants in urban park were assessed by in-situ measurements of following eight items; growth of crown(Gc), growth of shoots, individual tree volume(Vol), plant area index, woody area index, leaf area index, leaf chlorophyll content(Lc) and leaf water content(Lw). For validation, these measurements were compared with the ranks of holistic tree vigor condition, which were visually assessed using a 4-point grading scale based on the expert's knowledge. As a result, the measures of each evaluation item successfully highlighted a variety of aspects in tree vigor condition, including the states of both photosynthetic and non-photosynthetic parts. The variation in the results depending on evaluated parts was shown within an individual tree, even though the broad agreement among the results was found. The result of correlation analysis between the tested measurements and 4-point visual assessment, demonstrated that the state of water-stressed foliage of the season (Lw) or the development of plant materials since sapling phase (Vol) could be better viewed from the outer appearance of trees than other symptoms. But only based on the visual assessment, it may be difficult to detect the quality of photosynthesis (Lc) or the recent trend in growth of trees (Gc). To make this methodology simplified for the broad-scale application, the tested eight measurements could be integrated into two components by principal component analysis, which was labelled with 'the amount of plant materials' and 'vigor trend', respectively. In addition, the use of these quantitative and multi-scale indicators underlies the importance of assessing various aspects of tree vigor condition, taking into account the response(s) on different time and spatial scale of pressure(s) shown in each evaluated module. Future study should be advanced for various species at diverse developing stages and environment, and the application to wide areas at a periodic manner.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.169-176
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• 2020

Business going concern is an important issue to be addressed since it determines how companies will survive. One indicator of the going concern problem is going concern opinion. The going concern opinion is a result of evaluation of auditors on going concern assumption of financial reporting. This research aims to examine the effect of opinion shopping, prior opinion, audit quality, and financial condition on going concern opinion. Research sample consists of 80 listed manufacturing companies on the Indonesian Stock Exchange surveyed between 2013 and 2017. Analysis data uses logistic regression. Based on the result, prior opinion affects going concern opinion, while opinion shopping, audit quality, and financial condition have no effect on going concern opinion. The significant effect of prior opinion on going concern opinion indicates that auditors consider the evaluation of the previous condition of companies' concern problematic since going concern is hard to be solved in a short-term period. This research provides recommendations for companies to increase their business ability so going concern problem can be avoided. This research also suggests to auditors to consider prior opinion to issue current opinion since previous companies' condition can be used as a general picture to initiate the auditing process.