• Journal of the Korea Safety Management & Science
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• v.10 no.2
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• pp.15-24
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• 2008

This study was to investigate the relationship of VDT(visual display terminal) work condition and fatigue severity in the financial office workers. Questionnaires were completed by 662 persons in VDT workers of Post Office from January to May 2006. Multidimensional Fatigue Scale(MFS) that was developed in Korea Occupational Safety &Health Agency to estimate the degree of fatigue was used for study. In results, 149 persons(22.5%) in VDT workers were felt low fatigue severity, 351 workers(53.0%) were middle, and 162 workers (24.5%) were high. So it was appeared that one in four VDT workers felt the high fatigue severity. And woman VDT workers felt more fatigue severity than man. Also, fatigue severity was increased with increasing work time. Our findings suggest that VDT workers in financial office need proper health program to prevent occupational fatigue and disease.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.509-514
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• 2004

This paper introduces the modified slip energy recovery system in order to improve its power factor and to reduce harmonics of line current waveforms. Twelve pulse line commutated converter with the chopper type IGBT is applied where the chopper is applied across the DC terminal and the chopped DC is fed to the converter operating as an inverter and then passed through the wye-wye and delta-wye transformer circuit. This scheme leads to be able to adjust the speed of the motor by the duty cycle of the chopper operating in PWM mode. The fuzzy logic controller is also introduced to the modified slip energy recovery system for keeping the motor speed to be constant when the load varies. The experimental results in testing the 0.22 kW wound rotor induction motor from no-load condition to rated condition show the effectiveness of the proposed control scheme.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.237-237
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• 2004

Parthenogenesis and culture condition are essential to intracytoplasmic sperm injection and cloning by nuclear transfer. This study investigated apoptosis and in vitro development of parthenogenetic preimplantation porcine embryos. 42∼44 h in vitro matured oocytes derived from a local abattoir were used. Apoptotic cell death was analyzed by using a terminal deoxynucleatidyl transferase mediated deoxyuridine 5-triphoshate nick-end labling (TUNEL) assay. (omitted)

• Progress in Superconductivity and Cryogenics
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• v.2 no.1
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• pp.24-30
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• 2000

This paper present the characteristics of the internal induced voltage and arc phenomena in liquid helium at the energy transfer from a superconducting magnet to a load resistor. Especially generation mechanism of the oscillated wave from of the coil terminal voltage is analyzed by considering circuit constant of the superconducting magnet, load condition and arc resistance of the mechanical opening switch. The wavefront and peak portion of the voltage are strongly influenced by arc discharge triggered by the switch separation in liquid helium. Abrupt arc extinction leads to voltage oscillation with an enormous peak. It is suggested that the superconducting magnet should be designed to ensure the internal surge when arc is possibly formed by switch opening or coil short circuit between turns or layers. Finally, a suppression method of the oscillating surge is proposed based on the load condition.

• Journal of the Korean Society of Safety
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• v.27 no.3
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• pp.36-41
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• 2012

Electrical Connections often cause fires due to poor contact. Occurrence rate of these fires tends to increase annually. The reason why poor contacts occur is often because it is the low mechanical pressure at the contact points. A typical connection method using mechanical pressure is a screw terminal type. This study reviewed these poor contact cases in the screw terminals. In order to get reproduction of such cases, two types of experiments were conducted. the first one was conducted under the normal contact condition, and the other one was conducted under the poor contact condition that screw terminal of breaker was loosen and did not meet the requirements of toque value. In both types of experiments, compulsory vibration was adopted as a variable to aggravate poor contacts. Each of various current values(4.5A, 9.0A, 13.5A) is input. In these experiments, relationships of a contact, electrical signal such as current and electric pulse by ZCT and thermal characteristics according to vibration effect are analyzed. The suggested data and results in this study provide the useful resources helping to investigate fires due to poor contact, and they develop the detector for poor contact and finally reduce the electrical fire occurrence rate.

• The Journal of Internal Korean Medicine
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• v.41 no.3
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• pp.478-486
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• 2020

Objectives: Pressure injury is a common symptom of end-stage cancer, which impact quality of life. This case study reports on use of traditional Korean medicine in an end-stage cancer patient with pressure injury after debridement and local flap. Methods: A pressure injury with debridement and a local flap was treated using herbal medicine, a carbon arc, acupuncture, dressing, and cooperation in plastic surgery. Pressure injury was followed up with photographs. Results: On the 22^nd day of treatment (26 days after the debridement and local flap), redness, swelling, and the condition of pressure injury were all improved. Moreover, the condition of the pressure injury was good without dressing. Conclusions: These results show that traditional Korean medicine may have a positive effect on a pressure injury and improve the quality of life of cancer patients. However, further study is needed to confirm these findings.

• The Korean Society of Law and Medicine
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• v.17 no.2
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• pp.257-279
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• 2016

Recently, the Well-dying Act was legislated in Korea, and it will come into effect in August 4, 2017. This Act allows to withdraw the life sustaining treatment from impending death patients and also provide the hospice and palliative treatment to terminal patients. In the Supreme Court's case so called "Madam Kim", medical condition of Madam Kim was a persistent vegetative status owing to brain damage and her family members wanted to remove the artificial ventilation. In 2009, the Supreme Court allowed to withdraw the artificial ventilation under the specific conditions. We applied this new Well-dying Act to the Madam Kim's case hypothetically in order to know this Act can reasonably solve the problem of life sustaining treatment for dying or terminal patients. For the impending patients, the Well-dying Act has the problem not to withdraw the futile treatment due to the advance directives of patients. Vice versa, the terminal patients have no chance to withdraw the life sustaining treatment due to the this Act impose the duty to provide the hospice and palliative treatment despite of advance directives. We need to ruke out the persistent vegetative patients from the terminal patients caused by the cancer, acquired immune deficiency syndrome, chronic obstructive lung disease and chronic liver cirrhosis, In addition, we have to discuss the effect of the advance directives of terminal patients in view of self determination right.

• Journal of Advanced Navigation Technology
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• v.17 no.5
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• pp.516-523
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• 2013

In this paper, The path loss model of Air Traffic Control(ATC) telecommunication radio channel has been studied at the Incheon International Airport(IIA) with the terminal with two antlers. We measured two frequencies among VHF/UHF channel bands. The transmitting site radiated the Continuous Wave(CW). The propagation measurement was taken using the moving vehicle equipped with receiver and antenna. The transmitting power, frequency and antenna height are the same as the current operating condition. The path loss exponent and intercept parameters were extracted by the basic path loss model and hata model. The path loss exponents at passager terminal areas were 3.32 and 3.10 respectively in 128.2 MHz and 269.1 MHz. The deviation of prediction error is 9.69 and 9.65. The new path loss equation at the terminal area was also developed using the derived path loss parameters. The new path loss was compared with other models. This result will be helpful for the ATC site selection and service quality evaluation.

• Journal of Microbiology and Biotechnology
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• v.28 no.3
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• pp.439-447
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• 2018

The aromatic compound p-hydroxybenzoate (PHBA) is an important material with multiple applications, including as a building block of liquid crystal polymers in chemical industries. The cytochrome P450 (CYP) enzymes are beneficial monooxygenases for the synthesis of chemicals, and CYP53A15 from fungus Cochliobolus lunatus is capable of executing the hydroxylation from benzoate to PHBA. Here, we constructed a system for the bioconversion of benzoate to PHBA in Escherichia coli cells coexpressing CYP53A15 and human NADPH-P450 oxidoreductase (CPR) genes as a redox partner. For suitable coexpression of CYP53A15 and CPR, we originally constructed five plasmids in which we replaced the N-terminal transmembrane region of CYP53A15 with a portion of the N-terminus of various mammalian P450s. PHBA productivity was the greatest when CYP53A15 expression was induced at $20^{\circ}C$ in $2{\times}YT$ medium in host E. coli strain ${\Delta}gcvR$ transformed with an N-terminal transmembrane region of rabbit CYP2C3. By optimizing each reaction condition (reaction temperature, substrate concentration, reaction time, and E. coli cell concentration), we achieved 90% whole-cell conversion of benzoate. Our data demonstrate that the described novel E. coli bioconversion system is a more efficient tool for PHBA production from benzoate than the previously described yeast system.

• The Journal of Society for e-Business Studies
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• v.17 no.2
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• pp.149-163
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• 2012

Logistics systems provide their service to customers by coordinating the resources with limited capacity throughout the underlying processes involved to each other. To maintain the high level of service under such complicated condition, it is essential to carry out the real-time monitoring and continuous management of logistics processes. In this study, we propose a method of estimating the service completion time of key processes based on process-state information collected in real time. We first identify the factors that influence the process completion time by modeling and analyzing an influence diagram, and then suggest algorithms for quantifying the factors. We suppose the container terminal logistics and the process of discharging and loading containers to a vessel. The remaining service time of a vessel is estimated using a decision tree which is the result of machine-learning using historical data. We validated the estimation model using container terminal simulation. The proposed model is expected to improve competitiveness of logistics systems by forecasting service completion in real time, as well as to prevent the waste of resources.