• International Journal of Control, Automation, and Systems
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• v.6 no.2
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• pp.160-170
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• 2008

Temperature control of an enclosed thermal system which has many applications including Rapid Thermal Processing (RTP) of semiconductor wafers showed an input-constraint violation for nonlinear controllers due to inherent strong coupling between the elements [1]. In this paper, a constrained nonlinear optimal control design is developed, which accommodates input constraints using the linear algebraic equivalence of the nonlinear controllers, for the temperature control of an enclosed thermal process. First, it will be shown that design of nonlinear controllers is equivalent to solving a set of linear algebraic equations-the linear algebraic equivalence of nonlinear controllers (LAENC). Then an input-constrained nonlinear optimal controller is designed based on that LAENC using the constrained linear least squares method. Through numerical simulations, it is demonstrated that the proposed controller achieves the equivalent performances to the classical nonlinear controllers with less total energy consumption. Moreover, it generates the practical control solution, in other words, control solutions do not violate the input-constraints.

• International Journal of Precision Engineering and Manufacturing
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• v.6 no.4
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• pp.21-25
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• 2005

In the dynamic analysis of a mechanism, if one or more of the components are flexible, then the simulation will not be accurate because of the violation of the rigid body assumption. Mode shapes are used to represent the dynamic behavior of an elastic structure. A modal synthesis method which uses a combination of normal modes, constraint modes, and attachment modes, was used to represent effectively the elastic deformation of a flexible multibody. Since the combination of these modes should be different for each type of connecting part, the modal synthesis method was studied for the various types of interconnecting joints. In addition, the analysis procedure for the flexible body was explained. A satellite system with flexible solar panels was chosen as an example to show the effectiveness of the proposed method.

• Journal of Engineering Education Research
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• v.21 no.2
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• pp.3-6
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• 2018

A few thermodynamics texts are commonly found to have unrealistic example problems in which the process violates the second law of thermodynamics. This error would result from presentation order in the text which introduces first the first law for cycles, systems, and control volumes and then the second law later. In the presentation order, the example problems deal only with the first law without telling whether the process violates the second law. To correct this erroneous situation, it could be recommended to present the first law and the second law successively so that both laws could be applied simultaneously to the given example problems.

• Journal of Information Processing Systems
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• v.15 no.1
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• pp.169-180
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• 2019

Transmitting visual information over a broadcasting network is not only prone to a copyright violation but also is a forgery. Authenticating such information and protecting its authorship rights call for more advanced data encoding. To this end, electronic watermarking is often adopted to embed inscriptive signature in imaging data. Most existing watermarking methods while focusing on robustness against degradation remain lacking of measurement against security loophole in which the encrypting scheme once discovered may be recreated by an unauthorized party. This could reveal the underlying signature which may potentially be replaced or forged. This paper therefore proposes a novel digital watermarking scheme in temporal-frequency domain. Unlike other typical wavelet based watermarking, the proposed scheme employed the Lorenz chaotic map to specify embedding positions. Effectively making this is not only a formidable method to decrypt but also a stronger will against deterministic attacks. Simulation report herein highlights its strength to withstand spatial and frequent adulterations, e.g., lossy compression, filtering, zooming and noise.

• Journal of Medicine and Life Science
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• v.16 no.1
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• pp.10-12
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• 2019

Medical disputes can always arise in the medical environment. We aimed to decrease the medical disputes by analysis for causes and results of cases of medical disputes. The cases of medical dispute were found on the homepage of the Supreme Court based on the judgment data which was searched using the keyword 'Jeju, Medical accident' and it was described as the area related to each medical accident. There was total of 13 cases related medical disputes in Jeju. The final states of the patients were different in each causes, but death accounted for 10 cases (76.92%), comatose state for one and disability for two respectively. The cases were 2 related with an injury from a fall. The major cause was violation of medical care obligation. Physician have to learn recent medical knowledge, have competence, and explain the detailed procedures and complications before the procedures dependent on patient autonomy.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.2
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• pp.72-79
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• 2021

The present paper aims to set forth a two-dimensional theory for the dynamics of plates that is valid over a large range of excitation. To construct a dynamic plate theory within the long-wavelength approximation, two dimensional-reduction procedures must be used for analyzing the low- and high-frequency behaviors under the dynamic variational-asymptotic method. Moreover, a separate and logically independent step for the short-wavelength regime is introduced into the present approach to avoid violation of the positive definiteness of the derived energy functional and to facilitate qualitative description of the three-dimensional dispersion curve in the short-wavelength regime. Two examples are presented to demonstrate the capabilities and accuracy of all of the formulas derived herein by using various dispersion curves through comparison with the three-dimensional finite element method.

• Clinics in Shoulder and Elbow
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• v.25 no.4
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• pp.334-338
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• 2022

Currently, the literature contains few studies that describe any potential complications following arthroscopic acromioplasty. Because part of the anterior deltoid originates from the anterior acromion, there is a risk for violation and subsequent iatrogenic rupture or avulsion during this procedure. This type of injury can be a devastating problem for patients that may lead to poor function and debilitating pain. We present a patient with deltoid insufficiency following arthroscopic acromioplasty who elected to proceed with operative management with a planned arthroscopic evaluation of the shoulder followed by an open deltoid repair. At the final follow-up visit 2.5 years postoperatively, the patient reported improved pain from baseline and no residual disability and was able to perform most activities of daily living without difficulty. This case serves as an example of a surgical repair for a deltoid avulsion following arthroscopic acromioplasty. As there is still a lack of standard guidelines, our suture repair technique can be considered one method of treatment for this type of injury.

• Journal of Astronomy and Space Sciences
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• v.40 no.4
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• pp.217-224
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• 2023

The Korea Pathfinder Lunar Orbiter (KPLO), also known as Danuri, successfully entered its mission orbit on December 27, 2022 (UTC), and is currently performing its mission smoothly. To mitigate potential contingencies during the flight and to navigate the spacecraft into the desired lunar orbit, the KPLO flight dynamics (FD) team analyzed major trajectory-related contingencies that could lead to the violation of mission requirements and prepared operational procedures from the perspective of trajectory and FD. This paper presents the process of preparing contingency trajectory operations for the KPLO, including the identification of trajectory contingencies, prioritization results, and the development of recovery plans and operational procedures. The prepared plans were successfully applied to address minor contingencies encountered during actual operations. The results of this study will provide valuable insights to FD engineers preparing for space exploration mission operations.

• Journal of Digital Convergence
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• v.14 no.11
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• pp.37-44
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• 2016

This study aimed to investigate the mediating effect of perception of human rights victimization between school violence victimization and self-esteem of adolescents. For this study, 554 adolescents were surveyed at B county of Korea from September to November in 2015. Main results of this study were as follows. First, it was found out that school violence victimization was significantly different depending on school level. And perception of human rights victimization was significantly different depending on regions. But self-esteem was not. Second, school violence victimization and human rights victimization were positively correlated. And school violence victimization and self-esteem were negatively correlated. Third, perception of human rights victimization was perfectly mediated between school violence victimization and self-esteem of adolescents. Lastly, policy implications for the students with lower self-esteem due to school violence victimization were suggested.

• Asia-Pacific Journal of Business
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• v.11 no.2
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• pp.119-132
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• 2020

Purpose - This study seeks to deepen our understanding of abusive supervision and its negative consequences on subordinates. Specifically, it examines the underlying psychological mechanism between abusive supervision and subordinates' work engagement, in particular with its focus on the mediational role of psychological contract breach. Design/methodology/approach - Following the two rounds of pilot interviews, this study collected and analyzed 182 survey data from one construction company and one hospital - the sectors in which abusive supervision is known to be frequent, with one-month interval to avoid common methods variances. Findings - We have two key findings. First, abusive supervision is negatively related to subordinates' work engagement. Second, the psychological contract violation mediates the relationship between abusive supervision and subordinates' work engagement. Research implications or Originality - This study enriches extant research on abusive supervision by deepening our understanding of the underlying mechanism in which abusive supervision causes negative outcomes. On a practical note, companies need further efforts to address abusive supervision, for example, by introducing sophisticated HR practices, including accessible grievance procedures and more serious disciplinary actions, and/or by offering leadership educations to supervisors.