• Design & Manufacturing
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• v.16 no.4
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• pp.46-51
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• 2022

The piercing process of creating holes in sheet metals for mechanical fastening generates high shear force. Real-time monitoring technology could predict tool damage and product defects due to this severe condition, but there are few applications for piercing high-strength aluminum. In this study, we analyzed the load signal to predict the punch's wear level during the process with a piezoelectric sensor installed piercing tool. Experiments were conducted on Al6061 T6 with a thickness of 3.0 mm using piercing punches whose edge angle was controlled by reflecting the wear level. The piercing load increases proportionally with the level of tool wear. For example, the maximum piercing load of the wear-shaped punch with the tip angle controlled at 6 degrees increased by 14% compared to the normal-shaped punch under the typical clearance of 6.7% of the aluminum piercing tool. In addition, the tool wear level increased compression during the down-stroke, which is caused by lateral force due to the decrease in the diameter of pierced holes. Our study showed the predictability of the wear level of punches through the recognition of changes in characteristic elements of the load signal during the piercing process.

• Microbiology and Biotechnology Letters
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• v.43 no.3
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• pp.267-274
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• 2015

Biopharmaceuticals and the cell substrates used for their manufacture are currently tested for porcine adventitious viruses due to the widespread use of porcine trypsin in cell culture. Porcine transmissible gastroenteritis virus (PTGV) is one of the major adventitious porcine viruses causing contaminated during the manufacture of biopharmaceuticals. Therefore, rapid and sensitive detection of PTGV is essential in ensuring the safety of biopharmaceuticals. A TaqMan probe real-time RT-PCR method was developed for the quantitative detection of PTGV contamination in cell substrates, raw materials, manufacturing processes, and final products, as well as PTGV clearance validation. Specific primers for the amplification of PTGV RNA were selected, and PTGV RNA was quantified by use of a specific TaqMan probe. Specificity, limit of detection (LOD), and robustness of the method was validated according to international guidelines on the validation of nucleic acid amplification tests. The sensitivity of the assay was calculated to be 1.10 × 10⁰ TCID₅₀/ml. The real-time RT-PCR method was validated to be reproducible, very specific to PTGV, and robust. The established real-time RT-PCR assay was successfully applied to the validation of Chinese Hamster Ovary (CHO)-K1 cells artificially infected with PTGV.

• Toxicological Research
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• v.4 no.1
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• pp.1-12
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• 1988

In order to evaluate the effect of cigarette smoking on the pharmacokinetics of theophylline in Koreans, doses of 4.5 to 5.0 mg/kg of theophylline, as injectable aminophylline, were administered to 12 normal young volunteers (male, 22 to 35 yrs;mean, 26 yrs) through intravenous infusion over 30 minutes, and pharmacokinetics of theophylline were tested. Among subjects, six were nonsmokers and the other were smokers (range 1 to 2 packs/day). Also the correlations between plasma and saliva theophylline concentrations were investigated by determining the concentrations of theophylline in saliva simultaneously at each plasma sampling time. The total body clearances of theophylline in smokers (Mean${\pm}$SD, 0.0578${\pm}$0.0092 L/hr/kg)were appreciably higher than thoxe of nonsmokers (Mean${\pm}$SD, 0.0359${\pm}$0.0063 L/hr/kg), and the half-lives of theophylline in smokers averaged 5.36${\pm}$1.22hr, and significantly shorter than those of nonsmokers which averaged 9.14${\pm}$1.73hrs(p<0.005). But the apparent volumes of distribution of theophylline did not show any significant difference between smokers (Mean${\pm}$SD,0.44 ${\pm}$0.05L/kg) and nonsmokers (Mean${\pm}$SD, 0.46${\pm}$0.05L/kg). The average concentration ratios in saliva and plasma were 0.61 in smokers and 0.56 in nonsmokers after 2 hrs following drug administrations, and the smoker group had a slightly higher value of ratio(S/P) than the nonsmoker group (p<0.05). The correlations between saliva and plasma theophylline concentration in smokers were r=0.852(p<0.0005) within 2 hr and r=0.985(p<0.0005) after 2 hrs and also those of nonsmokers were r=0.729(p<0.0005) within 2 hrs and r=0.957(p<0.0005) after 2 hrs starting the infusion. From the results, it was found that smoking cigarettes had significantly increased the clearance of theophylline and that the relationships between saliva and plasma theophylline concentrations in all subjects were better after 2 hrs than within 2 hrs starting the infusion of aminophlline.

• The Journal of Korean Physical Therapy
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• v.9 no.1
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• pp.127-145
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• 1997

The purpose of this study wa9 to analyse the gait patterns of two female children with hemiplegic cerebral palsy by using the three-dimensional video motion analysis technique. Case 1 has mild spastic hemiplegia on the right side while Case 3 has moderate spastic hemiplegia on the left side. A group of 10, normal female children of the same age(7-8 years old) were selected as the control group for comparison. Time and distance variables as well as the Center of Mass displacement, and the pelvic and joint motions in three anatomical planes were analysed for this purpose. The following observations were made through the analysis : Case 1 revealed an asymmetrical gait pattern in which the step length of the unaffected side was shorter than that of the affected side, which wan a result of the effort to minimize loading on the affected leg by shortening the swing phase of the unaffected leg. Case 1 scored similar phase ratios, cadence and walking velocity to the normal group. A slight posterior tilt of the pelvis was observed throughout the gait cycle. Less hip and knee flexion than the normal group was observed, and demonstrated hyperextension of the knee in the terminal stance phase. The main problem in case 1 originated from the insufficient dorsiflexion of the affected foot during the swing phase. Therefore, Case 1 has difficulty with foot clearance in the swing phase. Usually, this is compensated for by using exessive hip abduction and medial rotation in conjuction with trunk elevation as well as increased vortical displacement of the center of mass. Case 1 revealed a foot-flat initial contact pattern. Case 2 was characterized by a consistent retraction ef the affected aide of the body througout the gait cycle, As a result, an asymmetrical gait pattern with increased stance phase ratios of the unaffected side was observed. In spite of this the step lengths of both sieds were similar. Case 2 scored lower cadence and walking speed than the normal group with lower gait stability. The main problem in Case 2 originated from an excessive plantaflexion of the affected foot which, in turn, rebutted in high hip and knee flexion. Hyperextension of the knee was observed at mid-stance, and execessive anterior tilt of the pelvis throughout the gait cycle was noticed. A gait pattern with high hip abduction and medial circumduction was maintained for the stability in the stance phase and foot clearance in the swing phase. Case 2 revealed a forefoot-contact initial contact pattern.

• Journal of the Korea Society of Computer and Information
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• v.3 no.3
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• pp.139-150
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• 1998

Due to development of science and telecommunication with wide-spread computer supply, it could be done through computer automatically instead of manpower-work for paper transportation & paper approval. It is developed to so-called Factory Automation. Further, it is developed to Office Automation. Trading companies & concerned trade authorities are interested in Trade Automation that such technique is applied to trade work. Generally, Trade Automation means to realize paperless trade by exchanging electronic papers through inter-computers after concerned trade operators transformed various papers to electronic papers that computer could read. In case Trade Automation fix in the trade business, it is expected one of innovations among traditional paper work of trade business, namely without going import-export authorities, Customs office, Banks. Shipping companies, Marine insurance companies on hand-carrying papers, it could be fast, simple, correct to finish every trade procedures such as commercial business, foreign currency, customs clearance, transportations, insurance. terms of payment, etc., with Electronic Data Interchange through computer facilities. Especially, telecommunication for trade form could be helpful to proceed trade paper with one-run-method Further we can anticipate 6 effects for Trade Automation as belows : First, as explained just above articles, with completion for Trade Automation, every trade procedures can be done by computer. so, time to work can be diminished. namely. logistics cost including accessory costs for trade procedures can be saved much. Second, viewing to private enterprise, effect of Office Automation can be maximized and rapid, correct exchange for various trade informations could raise efficiency of enterprise management establishing rational production, storage, transportation and could raise competition improving standard for consumers's service. Third, establishing Trade Automation systems makes it easier piling-up of harbor cargo by pre-transmission of electronic paper & trade informations make it possible to finish customs clearance in advance and can be dispatched upon cargo arrival. Fourth, most of concerned trade authorities such as import-export approval office. financial authorities, transport & insurance companies concentrated in Metropolitan area(Seoul, In -Cheon, Kyung-Ki). Therefore, in case Trade Automation could be realized. it is possible to proceed trade business instantly in every country area by computer facilities. Also. it contribute well-balanced development for suburb. region area by suburb dispersion of trading companies. Fifth, on the way to Trade Automation establishment & its enlargement process. producing enormous demand for over-all telecommunication such as hardware. software. network makes opportunity to progress telecommunication industry & concerned industries. Finally. Trade Automation accelerate change of employment structure leading unnecessary labors on the industries of office & logistics to manufacturing area.

• Journal of Pharmaceutical Investigation
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• v.9 no.2
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• pp.11-21
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• 1979

It has been reported from our department that a few agents, such as $K_2S_2O_5,\;NaHSO_3,$ nicotinamide have a marked stabilizing effect in vitro on metoclopramide which is relatively unstable compound. In order to study the effect of these stabilizers on the action of metoclopramide in vitro, the fate of this compound combined with $K_2S_2O_5,\;NaHSO_3$ and nicotinamide, respectively, was studied and furthermore, the change of the biological activity of metoclopramide due to these stabilizers was studied by using the isolated stomach strip of rat. The blood concentration of metoclopramide was measured by using Bakke's method at the various time after intravenous injection of the mixed metoclopramide solution with the stabilizers. In order to study the excretion of the drug, rabbits were anesthesized and catheterized into bladder for withdrawal of urine. After intravenous injection of the mixed metoclopramide solution, urine was collected for 5 hours and the conjugated forms of metoclopramide as well as the free form were determined by using Arita's method. In the biological study of the metoclopramide combined with stabilizers, the contractability of the isolated rat stomach strip was observed by using polygraph recorder. The results were following: 1. When metoclopramide was administered with nicotinamide as stabilizer, the blood concentration of the unchanged from and the rate of the clearance of this compound were very similar to that of metoclopramide alone. On the other hand, other stabilizers, $K_2S_2O_5\;and\;NaHSO_3$, brought about 40% decrease in blood concentration of the unchanged form at 15 min after intravenous injection however, the rate of clearance of metoclopramide with $K_2S_2O_5\;or\;NaHSO_3$ was very slow. 2. In the case of urinary excretion, the excretory pattern of the metabolites of metoclopramide with $NaHSO_3$ or nicotinamide was very similar to that of metoclopramide alone. But metodopramide plus $K_2S_2O_5$ group showed the maked depression of excretion for first 1 hour. 3. In composition of metabolites, when metoclopramide was administered with $K_2S_2O_5$ or $NaHSO_3$, the sulfonate conjugation was predominant. But the glucuronic acid conjugation was predominant in metoclopramide plus nicotinamide gronp. 4. In the experiments on the biological activity of the metoclopramide, this compound exhibited the marked contracting effect in isolatd rat stomach strip. Specially, the meetoclopramide combined with $K_2S_2O_5$ showed the strong contraction of the isolated strip, suggesting the potenciating effect of $K_2S_2O_5$ on the action of metoclopramide in the isolated strip.

• Korean Journal of Ecology and Environment
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• v.39 no.4 s.118
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• pp.424-434
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• 2006

This study investigates bacteria-zooplankton grazing link and factors affecting their grazing relationship at trophically different two sites (Paldang Dam and Kyungan Stream) of Lake Paldang Ecosystem from April to December, 2005. Zooplankton were divided into two size groups; microzooplankton (MICZ) : 60-200 ${\mu}m$ and macrozooplankton (MACZ): >200 ${\mu}m$), and their grazing rates on bacteria were conducted for each size group separately. Bacterial abundance and seasonal change pattern were similar between two sites. MICZ, mostly rotifers (e.g., Brachionus, Keratella, Polyathra) were numerically dominant at both sites, while carbon biomass was highest in cladocerans. Zooplankton biomass was higher at the Kyungan Steam site compared to Paldang Dam site, and their high biomass during spring decreased as they were passing through the storm events in summer season at both sites. Zooplankton clearance rate (CR) was high in spring and autumn while low in summer at Paldang Dam site. However, zooplankton CR was high during the summer at Kyungan Stream site. Bacterial C-flux was high in spring and autumn when MACZ (esp. cladecerans) developed at a high biomass level at both sites. Overall, MACZ community CR and carbon flux (C-flux) were higher than those of MICZ, and the degree of difference between them was higher at Kyungan Stream site. Short hydraulic residence time and physical disturbance caused by summer storm event appeared to affect the zooplankton grazing on bacteria at both sites. The results of this study indicate that bacteria are potentially important carbon source of zooplankton, and that both biotic (e.g,, prey and predator taxa composition and abundance) and physical parameters appear to alter energy transfer in the planktonic food web of this river-reservoir hybrid system.

• Journal of Ginseng Research
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• v.41 no.4
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• pp.487-495
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• 2017

Background: Although flowers of Panax ginseng Meyer (FPG), Panax quinquefolius L. (FPQ), and Panax notoginseng Burk. (FPN) have been historically used as both medicine and food, each is used differently in practice. Methods: To investigate the connection between components and enhancing immunity activity of FPG, FPQ, and FPN, a method based on a rapid LC coupled with quadrupole time-of-flight MS and immunomodulatory activity study evaluated by a carbon clearance test were combined. Results: According to quantitative results, the ratio of the total content of protopanaxatiol-type ginsenosides to protopanaxadiol-type ginsenosides in FPN was 0, but ranged from 1.10 to 1.32 and from 0.23 to 0.35 in FPG and FPQ, respectively. The ratio of the total content of neutral ginsenosides to the corresponding malonyl-ginsenosides in FPN ($5.52{\pm}1.33%$) was higher than FPG ($3.2{\pm}0.64%$) and FPQ ($2.39{\pm}0.57%$). The colorimetric analysis showed the content of total ginsenosides in FPQ, FPG, and FPN to be $13.75{\pm}0.60%$, $17.45{\pm}0.42%$, and $12.45{\pm}1.77%$, respectively. The carbon clearance assay indicated that the phagocytic activity of FPG and FPQ was higher than that of FPN. A clear discrimination among FPG, FPQ, and FPN was observed in the principal component analysis score plots. Seven compounds were confirmed to contribute strongly by loading plots, which may be the cause of differences in efficacy. Conclusion: This study provides basic information about the chemical and bioactive comparison of FPG, FPQ, and FPN, indicating that protopanaxtriol-type ginsenosides and malonyl-ginsenosides may play a key role in their enhancing immunity properties.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.1
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• pp.101-110
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• 2010

In this study, a prediction model for incident reaction time was developed so that we can cope with the increasing demand for information related to the accident reaction time. For this, the time for dealing with accidents and dependent variables were classified into incident grade, A, B, and C. Then, fifteen independent variables including traffic volume, number of accident-related vehicles and the accidents time zone were utilized. As a result, traffic volume, possibility of including heavy vehicles, and an accident time zone were found as important variables. The results showed that the model has some degree of explanatory power. In addition, when the CHAID Technique was applied, the Answer Tree was constructed based on the variables included in the prediction model for incident reaction time. Using the developed Answer Tree model, accidents firstly were classified into grades A, B, and C. In the secondary classification, they were grouped according to the traffic volume. This study is expected to make a contribution to provide expressway users with quicker and more effective traffic information through the prediction model for incident reaction time and the Answer Tree, when incidents happen on expressway

• Journal of Korean Society of Transportation
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• v.18 no.4
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• pp.7-18
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• 2000

KS-SIGNAL, a traffic signal optimization model for coordinated arterials, is an optimization model using the mixed integer linear Programming that minimizes total delay on arterials by optimizing left-turn Phase sequences. However, the Previous version of KS-SIGNAL had a difficulty in reducing computation speed because the related variables and constraints multiply rapidly in accordance with the increase of intersections. This study is designed to propose a new model, improving optimizing computation speed in KS-SIGMAl, and evaluate it. This Paper Puts forth three kinds of methodological approaches as to achieve the above goals. At the first step to reduce run-time in the proposed model objective function and a few constraints are Partially modified, which replaces variable in related to queue clearance time with constant, by using thru-movements at upstream intersection and the length of red time at downstream intersection. The result shows that the run-time can be reduced up to 70% at this step. The second step to load the library in LINDO for Windows, in order to solve mixed integer linear programming. The result suggests that run-time can be reduced obviously up to 99% of the first step result. The third step is to add constraints in related to left-turn Phase sequences. The proposed methodological approach, not optimizing all kinds of left-turn sequences, is more reasonable than that of previous model , only in the view of reducing run-tim. In conclusion, run-time could be reduced up to 30% compared with the second results. This Proposed model was tested by several optimization scenarios. The results in this study reveals that signal timing plan in KS-SIGNAL is closer to PASSER-II (bandwidth maximizing model) rather than to TRANSYT-7F(delay minimizing model).