• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.1383-1388
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• 2015

Proportional integral derivative (PID) control is one of the conventional control strategies. Industrial PID control has many options, tools, and parameters for dealing with the wide spectrum of difficulties and opportunities in manufacturing plants. It has a simple control structure that is easy to understand and relatively easy to tune. Injection mold is warming up to the idea of cycling the tool surface temperature during the molding cycle rather than keeping it constant. This “heating and cooling” process has rapidly gained popularity abroad. However, it has discovered that raising the mold wall temperature above the resin’s glass-transition or crystalline melting temperature during the filling stage is followed by rapid cooling and improved product performance in applications from automotive to packaging to optics. In previous studies, optimization methods were mainly selected on the basis of the subjective experience. Appropriate techniques are necessary to optimize the cooling channels for the injection mold. In this study, a digital signal processor (DSP)-based PID control system is applied to injection molding machines. The main aim of this study is to optimize the control of the proposed structure, including a digital PID control method with a DSP chip in the injection molding machine.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.12
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• pp.2827-2835
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• 2010

When the inferiorthreshold potential is applied on the membrane, the resting status membrane does not display any specific reaction, in the meanwhile if it receives somewhat higher voltages then it shows entirely different configuration. The fact that there is this kind of characteristics on the exciting membrane has been known for a long time, and some researchers have tried to analyze this situation using the electrical circuits but only limitted to inferiorthreshold potential case. The quantitative studies of especially for transthreshold stimulus is extremely rare up to now. The direct application of electrical circuit to biostatus is somewhat uneasonable because there may be much differences between them. We studied the electrical reaction quantitatively of biomembrane when it receives the transthreshold stimulus in point of electricity in this paper.

• Journal of Climate Change Research
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• v.8 no.3
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• pp.247-255
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• 2017

In this study, GHG inventory on 17 local government between 2005 and 2014 is build up using 'GHG emission estimation guideline (2016. 2) for local government' developed and distributed by KECO. This covers all the sectors should be included in national GHG inventory, which are energy, industrial process, agriculture, AFOLU, and waste. In addition, six GHGs, carbon dioxide, metane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, sulphur hexafluoride declared in Kyoto protocol are estimated to reflect utmost precision. Indirect esissions, such as electricity, heat and waste generation are separately estimated as well as direct emissions to help local government to establish substantial and implementable reduction measures of GHGs.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.7
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• pp.135-142
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• 2015

Human-powered self-generating devices have been attractive with its operation characteristic independent from outer environment such as weather condition and wind speed. However, conventional self-generators have low electric power output due to their weakly-coupled electromagnetic structure. More importantly, rotary crank motion which is usually adopted by conventional self-generator to generate electricity requires specific skeletal muscles to maintain large torque circular motion and consequently, causes fatigue on those muscles before it can generate enough amount of electricity for any practical application. Without improvement in electric power output and usability, the human-powered self-generator could not be used in everyday life. This study aims to develop a human-powered self-generator which realized a strong electromagnetic coupling in a closed-loop tubular structure (hula-hoop shape) for easy and steady long-term driving as well as larger electric output. The performance and usability of the developed human-powered generator is verified through experimental comparison with a commercial one. Additionally, human workload which is a key element of a human-powered generator but not often considered elsewhere, is estimated based on metabolic energy expenditure measured respiratory gas analyzer. Further study will focus on output and portability enhancement, which can contribute to the continuous power supply of mobile equipments.

• Biomedical Science Letters
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• v.13 no.1
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• pp.25-32
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• 2007

The purpose of this study was to investigate the effect of the high voltage pulsed Current (HVPC) stimulation on the healing rate and the proliferative activity of keratinocytes and IGF-I mRNA expression of an incisional wound in rat skin. Twenty male Sprague-Dawley rats ($265{\sim}290g$) were randomly divided into HVPC (n=10) and control group (n=10). Rats received 10 mm length of full-thickness incision wound on the back under the anesthesia. The HVPC group received electrical stimulation with a Current intensity of 50 V at 100 pps for a duration of 30 minutes, while the control group was given the same treatment without electricity for a week. Polarity was negative in first three days and positive thereafter. The wound length was measured and evaluated as percentage. The mean number of nucleolar organizer regions (NORs) per nucleus and level of IGF-I mRNA expression were calculated. The mean percent of wound closure were $51.17{\pm}17.76%$ and $80.71{\pm}11.91%$, respectively, in the sham treated control and HVPC stimulated groups (t=-4.308, P<0.001). The mean NOR number per nucleus of the keratinocytes in the control and HVPC group were $1.85{\pm}0.20$ and $2.70{\pm}0.23$, respectively (t=8.638, P<0.001). The IGF-I mRNA level were $0.76{\pm}0.44$ and $1.32{\pm}0.41$, respectively, in the control and HVPC stimulated wounds (t=2.906, P<0.01). There was a positive correlation between the mean NOR number per nucleus and IGF-l mRNA level with a Pearson product moment correlation coefficient of 0.72 (P<0.05). These findings suggest that the HVPC may activate the rRNA of the basal keratinocytes and upregulate the IGF-I mRNA levels by alteration of the electrical environment, and it may increase proliferative activity of the keratinocytes in the skin wound of the rat.

• Biomedical Science Letters
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• v.3 no.2
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• pp.177-185
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• 1997

This study was performed to investigat the prevalence rates disease in industrial workers (16, 453) in Pusan city from Jan. 1, 1993 to Dec. 31, 1995. The results were as follows: The male to female ratio was 1.9:1.0 and average age was 43$\pm$17 in male, 38$\pm$15 in female of subjects. The percentage value of patients was 14.0% in male, 7.4% in female of total patients 1, 932 (11.0%). The prevalence raters of pulmonary tuberculosis, hepatic disease, and occupational hearing loss were significantly increased in male than females (p<0.001). But anaemia and organic solvent poisonings significantly increased in females than males (p<0.001). The prevalence rates of hepatic disease increased significantly in below 29, 30-39 and 40-49 age groups, that of cardiovascular disease increased significantly in the age group over 50 years (p<0.001). According to industrial types, the prevalence rate of cadiovascular disease increased in electricity and constration and shoes and rubber in disease, there of hepatic disease increased in primary metal, transportation and maintenance and other industrial, those of occupational hearing loss in drink and food and machinery. The prevalence rate of disease increased significantly long working duration in all diseases except lead poisoning.

• Journal of Magnetics
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• v.15 no.4
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• pp.213-220
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• 2010

Since the hypothalamus immediately reacts to a nerve by processing all the information from the human body and the external stimulus being conducted, it performs a significant role in internal secretion; thus, a diverse and rapid stimulus pulse is required. By detecting Zero Detector accurately via the application of AVR on-Chip (ATMEL) using commercial electricity, chopping generates a stimulus pulse to the brain using an IGBT gate to designate a new magnetic stimulation following treatment and diagnosis. To simplify and generate a diverse range of stimuli for the brain, chopping can be used as a free magnetic stimulator. Then, commercial frequency (60Hz) is chopped precisely at the first level of the leakage transformer to deliver an appropriate stimulus pulse towards the hypothalamus when necessary. Discharge becomes stable, and the chopping frequency and duty-ratio provide variety after authorizing a high-pressure chopping voltage at the second level of the magnetic stimulator. These methods have several aims. The first is to apply a variable stimulus pulse via accurate switching frequency control by a voltaic pulse or a pulse repetition rate, according to the diagnostic purpose for a given hypothalamus. Consequently, the efficiency tends to increase. This experiment was conducted at a maximum of 210 W, a magnetic induced amplitude of 0.1~2.5 Tesla, a pulse duration of $200{\sim}350\;{\mu}s$, magnetic inducement of 5 Hz, stimulus frequency of 0.1~60 Hz, and a duration of stimulus train of 1~10 sec.

• Journal of Life Science
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• v.25 no.8
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• pp.953-959
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• 2015

Optogenetics is the combination of optical and molecular strategies to control designated molecular and cellular activities in living tissues and cells using genetically encoded light-sensitive proteins. It involves the use of light to rapidly gate the membrane channels that allows for ion movement. Optogenetics began with the placing of light-sensitive proteins from green algae inside specific types of brain cells. The cells can then be turned on or off with pulses of blue and yellow light. Using the naturally occurring algal protein Channelrhodopsin-2 (ChR2), a rapidly gated light-sensitive cation channel, the number and frequency of action potentials can be controlled. The ChR2 provides a way to manipulate a single type of neuron while affecting no others, an unprecedented specificity. This technology allows the use of light to alter neural processing at the level of single spikes and synaptic events, yielding a widely applicable tool for neuroscientists and biomedical engineers. An improbable combination of green algae, lasers, gene therapy and fiber optics made it possible to map neural circuits deep inside the brain with a precision that has never been possible before. This will help identify the causes of disorders like depression, anxiety, schizophrenia, addiction, sleep disorder, and autism. Optogenetics could improve upon existing implanted devices that are used to treat Parkinson’s disease, obsessive-compulsive disorder and other ailments with pulses of electricity. An optogenetics device could hit more specific subsets of brain cells than those devices can. Applications of optogenetic tools in nonneuronal cells are on the rise.