• Bulletin of the Korean Mathematical Society
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• v.60 no.4
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• pp.1071-1083
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• 2023

The main motivation of this paper is to introduce and study the notions of strong Dedekind rings and semi-regular injective modules. Specifically, a ring R is called strong Dedekind if every semi-regular ideal is Q₀-invertible, and an R-module E is called a semi-regular injective module provided Ext¹_R(T, E) = 0 for every 𝓠-torsion module T. In this paper, we first characterize rings over which all semi-regular injective modules are injective, and then study the semi-regular injective envelopes of R-modules. Moreover, we introduce and study the semi-regular global dimensions sr-gl.dim(R) of commutative rings R. Finally, we obtain that a ring R is a DQ-ring if and only if sr-gl.dim(R) = 0, and a ring R is a strong Dedekind ring if and only if sr-gl.dim(R) ≤ 1, if and only if any semi-regular ideal is projective. Besides, we show that the semi-regular dimensions of strong Dedekind rings are at most one.

• Smart Structures and Systems
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• v.22 no.2
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• pp.167-174
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• 2018

Digital input and output modules are widely used to connect digital sensors and actuators to automation systems. Digital I/O modules provide flexible connectivity extension to numerous sensors and actuators and protect systems from high voltages and currents by isolation. Components in digital I/O modules are inevitably affected by operating and environmental conditions, such as high voltage, high current, high temperature, and temperature cycling. Because digital I/O modules transfer signals or isolate the systems from unexpected voltage and current transients, their failures may result in signal transmission failures and damages to sensitive circuitry leading to system malfunction and system shutdown. In this study, the lifetime of optocouplers, one of the critical components in digital I/O modules, was predicted using Bayesian tracking approaches. Accelerated degradation tests were conducted for collecting the critical performance parameter of optocouplers, current transfer ratio (CTR), during their lifetime. Bayesian tracking approaches, including extended Kalman filter and particle filter, were applied to predict the failure. The performance of each prognostic algorithm was then compared using accuracy and robustness-based performance metrics.

• Bulletin of the Korean Mathematical Society
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• v.53 no.5
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• pp.1341-1352
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• 2016

Let R be a commutative Noetherian ring, ${\Phi}$ a system of ideals of R and $I{\in}{\Phi}$. In this paper among other things we prove that if M is finitely generated and $t{\in}\mathbb{N}$ such that the R-module $H^i_{\Phi}(M)$ is $FD_{{\leq}1}$ (or weakly Laskerian) for all i < t, then $H^i_{\Phi}(M)$ is ${\Phi}$-cofinite for all i < t and for any $FD_{{\leq}0}$ (or minimax) submodule N of $H^t_{\Phi}(M)$, the R-modules $Hom_R(R/I,H^t_{\Phi}(M)/N)$ and $Ext^1_R(R/I,H^t_{\Phi}(M)/N)$ are finitely generated. Also it is shown that if cd I = 1 or $dimM/IM{\leq}1$ (e.g., $dim\;R/I{\leq}1$) for all $I{\in}{\Phi}$, then the local cohomology module $H^i_{\Phi}(M)$ is ${\Phi}$-cofinite for all $i{\geq}0$. These generalize the main results of Aghapournahr and Bahmanpour [2], Bahmanpour and Naghipour [6, 7]. Also we study cominimaxness and weakly cofiniteness of local cohomology modules with respect to a system of ideals.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.534-538
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• 2000

The new-type measuring modules for unmanned remote supervisory system using mobile communication network have been designed in this study. Measuring modules consist of temperature measuring module, humidity measuring module and human body sensing module. And we will design a main part to collect and process informations of each modules, evaluate reliability of combined total system.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.243-244
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• 2018

This study focused on the fact that there are a lot of alleys in some areas of the Urban Renewal New Deal project. In this study, we proposed a method to construct a spatial module by combining small modules. It is expected that the combination of small modules developed in this way will help revitalize the New Deal of Urban Regeneration. In the future, additional joint details will be developed, structure review will be conducted.

• The Korean Nurse
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• v.33 no.3
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• pp.56-69
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• 1994

This study was done to develop self - directed learning modules related to asepsis and elimination including urine and stool for Fundamentals in Nursing practice education contents and to measure the effectiveness of those modules. The subjects of this study were 96 sophomore students in the nursing college. Self-directed learning modules were developed by the researcher on the basis of the Lippincott Learning System of Kruger (1986) and Modules for Basic Nursing Care of Ellis (1992). Videotape was editted by using videotape made by the Lippincott Company and Film strip made by the Trainex Company with Korean dubbing. Self-directed learning was done for one week with the asepsis module and two weeks with the elimination modules after confirming the requiered level of knowledge acquisition through pre-test. For measuring proficiency in self-directed learning, a written test for cognitive domain, a sufficiency test for psychomotor domain, and a confidnece examination for affective domain were given. The data were analyzed using descritive statistics, and Pearson correlation coefficient using a SPSS-PC program. The results are summarized as follows: 1. Sufficiency test and confidence examination grades showed high levels in both asepsis and elimination. 2. Written test grades showed a high level in asepsis and elimination of urine but showed a medium level in eliminationin of stool. 3. Grades of sufficiency and confidence in asepsis and elimination practice were statistically significant with a moderate positive correlation (r=0.4- 0.5, p<0.001). 4. Grades of sufficiency and written tests in asepsis and elimination practice also were statistically significant with a moderate positive correlation (r=0.5-0.7, p<0.001). 5. Students showed relatively high contentment with the self-directed learning modules themselves but revealed relatively low contentment with video program and the self-directed learning process. In conclusion, this study disclosed that proficiency levels in cognitive, affective, and psychomotor domains were high when asepsis and elimination modules were applied. Also students showed high satisfaction with the modules themselves, but didn't show high contentment with the video programs. In considering low contentment with the self-directed learning process, it is estimated the students had experienced some difficulties about using self-directed learning modules because this was their first exposure to the self-directed learning module and they were already accustomed to the demonstration-practice method.

• Honam Mathematical Journal
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• v.38 no.2
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• pp.259-267
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• 2016

A module M over an associative ring R with unity is a QTAG-module if every finitely generated submodule of any homomorphic image of M is a direct sum of uniserial modules. Recently, the authors introduced the classes of QTAG-modules namely as socle-regular and strongly socle-regular QTAG-modules which properly contain the classes of transitive and fully transitive QTAG-modules respectively. Here we define strongly and quasi transitivities and study the inter relations between various type of transitivities.

• Communications of the Korean Mathematical Society
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• v.32 no.2
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• pp.277-285
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• 2017

In the various module generalizations of the concepts of prime (semiprime) for a ring, the question "when are semiprime modules subdirect product of primes?" is a serious question in this context and it is considered by earlier authors in the literature. We continue study on the above question by showing that: If R is Morita equivalent to a right pre-duo ring (e.g., if R is commutative) then weakly compressible R-modules are precisely subdirect products of prime R-modules if and only if dim(R) = 0 and R/N(R) is a semi-Artinian ring if and only if every classical semiprime module is semiprime. In this case, the class of weakly compressible R-modules is an enveloping for Mod-R. Some related conditions are also investigated.

• Journal of Korean Society for Quality Management
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• v.28 no.1
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• pp.210-219
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• 2000

When an electronic control system has been used for long time, the electronic control system becomes obsolete and no longer In production. In this case, the existing control system should replace by new system due to shortage of spare modules. However, if the proper number of spare modules are stocked, it may be possible and more economical than to replace by new system to extend the usage period of the existing control system. In this case, it is an important problem to determine the proper number of spare modules. In this paper, a method to determine the proper number of spare modules is presented with an application example.

• Journal of the Korean Mathematical Society
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• v.50 no.1
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• pp.203-218
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• 2013

Let R be a ring. A right R-module M is called GI-flat if $Tor^R_1(M,G)=0$ for every Gorenstein injective left R-module G. It is shown that GI-flat modules lie strictly between flat modules and copure flat modules. Suppose R is an $n$-FC ring, we prove that a finitely presented right R-module M is GI-flat if and only if M is a cokernel of a Gorenstein flat preenvelope K ${\rightarrow}$ F of a right R-module K with F flat. Then we study GI-flat dimensions of modules and rings. Various results in [6] are developed, some new characterizations of von Neumann regular rings are given.