• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.187-194
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• 2007

In order to utilize different nitrogen sources and to survive in a situation of nitrogen limitation, microorganisms have developed sophisticated mechanisms to adapt their metabolism to a changing nitrogen supply. In this communication, the recent knowledge of nitrogen regulation in the amino acid producer Corynebacterium glutamicum is summarized. The core adaptations of C. glutamicum to nitrogen limitation on the level of transcription are controlled by the global regulator AmtR. Further components of the signal pathway are GlnK, a $P_{II}-type$ signal transduction protein, and GlnD. Mechanisms involved in nitrogen control in C. glutamicum regulating gene expression and protein activity are repression of transcription, protein-complex formation, protein modification by adenylylation, change of intracellular localization, and proteolysis.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.3 s.96
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• pp.38-46
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• 1999

Spindle motor current is used to estimate the cutting force indirectly and control the feed rate for the cutting force regulation. The proposed algorithm is implemented to a DSP board based hardware for the industrial application. The software to make POP terminal communicate with the DSP board and POP server is coded under Windows 95 environment. Experiments under varying cutting conditions show that the DSP board recognizes the information of installed cutting tool and cutting conditions delivered from the POP server to use them for the proper control of the feed rate. The cutting force is regulated well during machining of tapered or stepped workpiece and circular shaped workpiece as well.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.1
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• pp.113-120
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• 1994

The dynamic characteristics of turning processes are complex, non-linear and time-varying. Consequently, the conventional techniques based on crisp mathematical model may not guarantee cutting force regulation. This paper presents a fuzzy controller which can regulate cutting force in turning process under varying cutting conditions. The fuzzy control rules are extablished from operator experience and expert knowledge about the process dynamics. Regulation which increases productivity and tool life is achieved by adjusting feedrate according to the variation of cutting conditions. The performance of the proposed controller is evaluated by cutting experiments in the converted conventional lathe. The results of experiments show that the proposed fuzzy controller has a good cutting force regulation capability in spite of the variation of cutting conditions.

• Proceedings of the KSR Conference
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• 1998.11a
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• pp.210-218
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• 1998

The ATO(Automatic Train Operation) System is used for train operation instead of drivers. It is interfaced with TCMS(Train Control and Monitoring System) and ATC/TWC system in the train and wayside facilities. In this paper describes configuration of ATO, specification of ATO hardware, construction of ATO software and the algorithm fur automatic train speed regulation in the carborn ATO system. ATO Application Software is consist of ART, SPR, REG, SRV and PSM tasks. ART task is main control part of the ATO that determine ATO control, ATO mode, state transition. SPR determine speed reference according to train motion status, track data, train data and restricted train speed. REG task regulated train speed form the starting of one station to the precision stop at the other station under the result of ART and SPR tasks. In this paper, a algorithm for the train speed regulation while running is described.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.165-170
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• 1997

In this paper, we consider the aortic sinus baroreceptor, which is the most representative baroreceptors sensing the variance of pressure in the cardiovascular system(CVS), and propose heart activity control model to observe the effect of delay time in heart period and stroke volume under the regulation of baroreflex in arotic sinus. The proposed heart activity baroreflex regulation model contains CVS electric circuit sub-model, baroreflex regulation sub-model and time delay sub-model. In these models, applied electric circuit sub-model is researched by B.C.Choi and the baroreflex regulation sub-model transforms the input, the arotic pressure of CVS electric circuit sub-model, to outputs, heart period and stroke volume by mathematical nonlinear feedback. We constituted the time delay sub-model to observe sensitivity of heart activity baroreflex regulation model by using the variable value to represent the control signal transmission time from the output of baroreflex regulation model to efferent nerve through central nervous system. The simulation object of this model is to observe variability of the CVS by variable value in time delay sub-model. As simulation results, we observe three patterns of CVS variability by the time delay. First, if the time delay is over 2.5 sec, arotic pressure, stroke volume and heart rate is observed nonperiodically and irregularly. Second, if the time delay is from between 0.1 sec and 0.25 sec, the regular oscillation is observed. Finally, if time delay is under 0.1 sec, then heart rate and arotic pressure-heart rate trajectory is maintained in stable state.

• Korean journal of communication and information
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• v.50
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• pp.29-49
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• 2010

Various opinions are expressed about the Internet Regulation. Some people argue that it is impossible to control because of the technical characteristics of Internet, while other people argue that it is easy to control. Recently in Korea, a move to reinforce the Internet Regulation through the extension of cyber real-name system is emerging, whereas the concern for its excessive infringement of the Freedom of Expression is increasing. This paper was intended to draw a reasonable direction for Internet Regulation in our society. And accordingly this paper tried to suggest a desirable direction of Internet Control in the future and to draw a criterion for domestic court judgement by analyzing cases of cyber defamation so far. The result of this study proposed that the Freedom for Expression be widely secured in the case of cyber defamation of criticism and political comments upon public officials and that the legitimacy and effectiveness of Internet Regulation be ensured. This result of study is expected to help establish the direction and principle of Internet Regulation in the future around Korea Communications Commission and Korea Communications Standards Commission.

• Journal of the Korean Society of Safety
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• v.27 no.3
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• pp.77-82
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• 2012

The leakage of toxic chemicals impact seriously on human being and environment, therefore during their treatment process, a proper management system is necessary to control their toxic effect. This study was designed to suggest the management regulation that supports business managers and facilities management. There are no extra regulation to control emergency accidents and terrors in chemical facilities. Developed countries like USA operate the management standards to control the toxic chemical and facilities according to their toxicity and processes. In order to solve this problem, we have analysed the advanced nations standard methods of security in chemical plants to study the new security management regulation which helps to prevent the chemical accidents. Especially, in USA, CCPS (Center for Chemical Process Safety), SVA (Security Vulnerability Assessment) and RBPSs (Risk-Based Performance Standards) of DHS (Department of Homeland Security) were invest I gated. On the basis of the results, we have suggested the application methods of the security and safety regulation in Korea.

• BMB Reports
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• v.57 no.5
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• pp.232-237
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• 2024

This study investigated how adipose tissue-derived mesenchymal stem cells (AT-MSCs) respond to chondrogenic induction using droplet-based single-cell RNA sequencing (scRNA-seq). We analyzed 37,219 high-quality transcripts from control cells and cells induced for 1 week (1W) and 2 weeks (2W). Four distinct cell clusters (0-3), undetectable by bulk analysis, exhibited varying proportions. Cluster 1 dominated in control and 1W cells, whereas clusters (3, 2, and 0) exclusively dominated in control, 1W, and 2W cells, respectively. Furthermore, heterogeneous chondrogenic markers expression within clusters emerged. Gene ontology (GO) enrichment analysis of differentially expressed genes unveiled cluster-specific variations in key biological processes (BP): (1) Cluster 1 exhibited up-regulation of GO-BP terms related to ribosome biogenesis and translational control, crucial for maintaining stem cell properties and homeostasis; (2) Additionally, cluster 1 showed up-regulation of GO-BP terms associated with mitochondrial oxidative metabolism; (3) Cluster 3 displayed up-regulation of GO-BP terms related to cell proliferation; (4) Clusters 0 and 2 demonstrated similar up-regulation of GO-BP terms linked to collagen fibril organization and supramolecular fiber organization. However, only cluster 0 showed a significant decrease in GO-BP terms related to ribosome production, implying a potential correlation between ribosome regulation and the differentiation stages of AT-MSCs. Overall, our findings highlight heterogeneous cell clusters with varying balances between proliferation and differentiation before, and after, chondrogenic stimulation. This provides enhanced insights into the single-cell dynamics of AT-MSCs during chondrogenic differentiation.

• The Journal of Korean Society for School & Community Health Education
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• v.21 no.2
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• pp.39-57
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• 2020

Objectives: This study was to develop a measurement scale that explains aggressive regulation behavior of middle school student, based on Ajzen's Theory of Planned Behavior (TPB) and verify its validity and reliability. Methods: The basic items were modified by selecting 41 items of middle school student aggressive behavior measurement scale. Through the content validity test, 63 first preliminary question items and 42 second preliminary question items were developed. The participants were 286 middle school students. The collected data were analyzed using content validity, correlation coefficient, exploratory factor analysis, confirmatory factor analysis, reliability and Cronbach α. Results: In this study, it was proved that the most important variable showing aggressive regulation behavior was aggressive regulation intention. This study was composed of 4 factors for direct measurement(attitude toward the behavior, subjective norm, perceived behavioral control, behavior intention) and 5 factors for indirect measurement(behavioral beliefs, outcome evaluation, normative beliefs, motivation to comply, control beliefs). The total variance was 65.4% and 67.6%, respectively, and the reliability was .90, .82. Finally, 42 questions were developed. Conclusion: We found the questionnaire used in this study was valid and reliable as a measure scale to explain the aggressive regulation behavior of middle school student based on TPB. Therefore, it is concluded that the aggressive regulation behavior scale could be a useful scale for the measurement of the aggressive regulation behavior of middle school student.

• Journal of Korean Academy of Nursing
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• v.52 no.1
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• pp.36-51
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• 2022

Purpose: The purpose of this study was to examine the effects of electroencephalogram (EEG) biofeedback training for emotion regulation and brain homeostasis on anxiety about COVID-19 infection, impulsivity, anger rumination, meta-mood, and self-regulation ability of late adolescents in the prolonged COVID-19 pandemic situation. Methods: A non-equivalent control group pretest-posttest design was used. The participants included 55 late adolescents in the experimental and control groups. The variables were evaluated using quantitative EEG at pre-post time points in the experimental group. The experimental groups received 10 sessions using the three-band protocol for five weeks. The collected data were analyzed using the Shapiro-Wilk test, Wilcoxon rank sum test, Wilcoxon signed-rank test, t-test and paired t-test using the SAS 9.3 program. The collected EEG data used a frequency series power spectrum analysis method through fast Fourier transform. Results: Significant differences in emotion regulation between the two groups were observed in the anxiety about COVID-19 infection (W = 585.50, p = .002), mood repair of meta-mood (W = 889.50, p = .024), self-regulation ability (t = - 5.02, p < .001), self-regulation mode (t = - 4.74, p < .001), and volitional inhibition mode (t = - 2.61, p = .012). Neurofeedback training for brain homeostasis was effected on enhanced sensory-motor rhythm (S = 177.00, p < .001) and inhibited theta (S = - 166.00, p < .001). Conclusion: The results demonstrate the potential of EEG biofeedback training as an independent nursing intervention that can markedly improve anxiety, mood-repair, and self-regulation ability for emotional distress during the COVID-19 pandemic.