• Journal of the Korean Society for Precision Engineering
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• v.13 no.12
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• pp.30-37
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• 1996

On-line process control equipment for CO$_{2}$ laser cutting is not available for industrial applications. The major part of the industrial laser cutting machines are adjusted off-line by highly educated engineers. The quality inspection of the sample is visual and referred to different quality scales. Due to the lack of automation the potential laser users hesitate to implement the cutting method. The first step toward an automation of the process is the development of a process monitoring system and the research is cincentrated on the area of on-line quality monitoring during CO$_{2}$ laser cutting. The method is based on the detection of the emitted light from the cutting front by photo diode. The developed monitoring system consists of the OP Amplifier, A/D convertor, power supply and PC. The signal from the photo diode has been undertaken from Fourier analysis and statistical analysis with real time. The photograph of striation pattern was taken by metallurgical microscope. As a result, it is possible to predict the striation pattern according to the beam traveling speed.

• International Journal of Contents
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• v.18 no.1
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• pp.17-26
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• 2022

With the acceleration of urbanization and industrialization, air pollution has become increasingly serious, and the pollution control situation is not optimistic. Climate change has become a major global challenge faced by mankind. To actively respond to climate change, China has proposed carbon peak and carbon neutral goals. However, atmospheric pollutants and meteorological factors that affect air quality are complex and changeable, and the complex relationship and correlation between them must be further clarified. This paper uses China's 2013-2018 high-resolution air pollution reanalysis open data set, as well as statistical methods of the Pearson Correlation Coefficient (PCC) to calculate and visualize the design and analysis of environmental monitoring big data, which is intuitive and it quickly demonstrated the correlation between pollutants and meteorological factors in the temporal and spatial sequence, and provided convenience for environmental management departments to use air quality routine monitoring data to enable dynamic decision-making, and promote global climate governance. The experimental results show that, apart from ozone, which is negatively correlated, the other pollutants are positively correlated; meteorological factors have a greater impact on pollutants, temperature and pollutants are negatively correlated, air pressure is positively correlated, and the correlation between humidity is insignificant. The wind speed has a significant negative correlation with the six pollutants, which has a greater impact on the diffusion of pollutants.

• Journal of Dental Rehabilitation and Applied Science
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• v.21 no.1
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• pp.43-57
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• 2005

Temporomandibular disorders have been defined as a collective term embracing a number of clinical problems that involve the temporomandibular joint, the masticatory nuscles, and associated structures. There have been many different contributing factors of TMDs which were traumatic, occlusal, pathophysiological and psychosocial. Among there factors, the effect of occlusion on TMDs have been a controversy for a long time. The purpose of this study was to investigate the effect of occlusal factors and oral habits on TMDs. In this study, 140 subjects with signs and symptoms of TMDs and diagnosed of TMD in the Orofacial Pain clinic of Yonsei University Dental Hospital though March to July 2004 were selected for the TMDs group and 50 subjects without any signs and symptoms of TMDs as the control group. The subjects were evaluated clinically in TMDs' Occlusal and Prosthodontic Restoration examinations. TMDs' examination was composed of the TMJ pain, sound, locking, temporal or masseter muscle palpation, mandibular movement, oral habits and headache. Occlusal examination was made of overjet, overbite, lost teeth number, nonfunctional interference, midline shift, then pattern of lateral movement and attrition. prosthodontic restoration examination had the existence of restoration, placement, then number of crown or bridge and Satisfiable index which estimated the quality of occlusal state of prosthodontic restorations. Following results were obtained : 1. The prevalence of TMDs was higher in their 20s & 30s, female of the TMD patients group. 2. The clenching frequency in the TMDs group(40.71%) was higher than those in the control group(18.00%), and there was a significant statistical difference(p<0.05). 3. The frequency of Nonfunctional interference in the TMDs group(10.00%) was higher than those in then Control group(2.00%), and there was a significant statistical difference(p<0.05). The result of this study indicated TMDs prevalence was higher in their 20s, 30s, female group of TMDs patients similar to the previous studies. Clenching and nonfunctional interference were estimated as the contributing factors of TMDs.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.1
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• pp.130-139
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• 2016

The purpose of this paper is to analyze the problems and the sources of defective products and draw improvement plans in a small plastic boat manufacturing process using TOC (Theory Of Constraints) and statistical analysis. TOC is a methodology to present a scheme for optimization of production process by finding the CCR (Capacity Constraints Resource) in the organization or the all production process through the concentration improvement activity. In this paper, we found and reformed constraints and bottlenecks in plastic boat manufacturing process in the target company for less defect ratio and production cost by applying DBR (Drum, Buffer, Rope) scheduling. And we set the threshold values for the critical process variables using statistical analysis. The result can be summarized as follows. First, CCRs in inventory control, material mix, and oven setting were found and solutions were suggested by applying DBR method. Second, the logical thinking process was utilized to find core conflict factors and draw solutions. Third, to specify the solution plan, experiment data were statistically analyzed. Data were collected from the daily journal addressing the details of 96 products such as temperature, humidity, duration and temperature of heating process, rotation speed, duration time of cooling, and the temperature of removal process. Basic statistics and logistic regression analysis were conducted with the defection as the dependent variable. Finally, critical values for major processes were proposed based on the analysis. This paper has a practical importance in contribution to the quality level of the target company through theoretical approach, TOC, and statistical analysis. However, limited number of data might depreciate the significance of the analysis and therefore it will be interesting further research direction to specify the significant manufacturing conditions across different products and processes.

• Journal of Bio-Environment Control
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• v.7 no.4
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• pp.276-282
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• 1998

This experiment was carried out to elucidate the effect of ethychlozate foliar application on the fruit quality of Miyagawa Early Satsuma Mandarin in the plastic house. Ethychlozate(100mg.L$^{-1}$ ) was applied to the fruit at 100, 115 and 145 days after full bloom stage. The fruit was divided into four frequency level groups, with the control group receiving no Ethychlozate treatment and the level 3 group receiving all three applications. Peel coloration by a value Increased as application frequency increased. The a/b value trend was seen to be similar to this, but the b value ran contrary to the a value trend. Glucose contents of the fruit juice did not differ statistically among the application frequency levels but the fructose level was seen to be higher with increasing application frequency. Sucrose showed a similar trend to fructose in that it had a tendency to increase as application frequency increased. As a result of this, total sugar increased naturally with application frequency. The average Brix level among all treatment groups was higher than the average Brix level in the control group but Brix level did not differ significantly among application frequency levels. Acidity had a tendency to increase as application frequency increase, but there was no statistical difference found.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.216-222
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• 2010

This study was carried out to determine the effects of olive oil prepared tomato powder (OPTP) used as lycopene source on fresh pork patties. OPTP was not added (0%; C), or was added at 0.25% (T1), 0.5% (T2), 0.75% (T3) and 1.0% (T4) in a basic pork patty formula and patties were stored for 7 days at $5^{\circ}C$. pH values of T3 and T4 were lower (p<0.05) than those of control until storage day 3. However, pH values of treated samples were dramatically increased (p<0.05) after 7 d of storage. Cooking loss values of treatments were lower (p<0.05) than those of control at day 1 of storage. Thiobarbituric acid reacting substances values were lower (p<0.05) in all treatments than in untreated samples during storage. All treated samples had lower values (p<0.05) for lightness ($L^*$) but significantly higher values (p<0.05) for redness ($a^*$) and yellowness ($b^*$) than the untreated samples during storage. Total plate counts of T4 were lower (p<0.05) than others during storage. In sensory evaluation, the scores of color, aroma and overall acceptability in T3 and T4 scored higher (p<0.05) than those of control at days 1 and 3 of storage, however, statistical significance was not found (p>0.05) among the samples after 7 days of storage. In conclusion, tomato powder-treated groups were significantly higher in redness ($a^*$) and yellowness ($b^*$), and lipid oxidation was inhibited, as compared with control during storage. Therefore, as a natural additive, tomato powder could be used to extend the self-life of meat products, providing the consumer with food containing natural additives, which might be seen more healthful than those of synthetic origin.

• Journal of Korean Society on Water Environment
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• v.36 no.6
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• pp.535-545
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• 2020

This study aims to conserve and monitor energy use in public sewage treatment plants by utilizing data from the SCADA system and by controlling the aeration rate required for maintaining effluent water quality. Power consumption in the sewage treatment process was predicted using the equipment's uptime, efficiency, and inherent power consumption. The predicted energy consumption was calibrated by measured data. Additionally, energy efficiency indicators were proposed based on statistical data for energy use, capacity, and effluent quality. In one case study, a sewage treatment plant operated via the SBR process used ~30% of energy consumed in maintaining the bioreactors and treated water tanks (included decanting pump and cleaning systems). Energy consumption analysis with the K-ECO Tool-kit was conducted for unit processing. The results showed that about 58.7% of total energy consumed was used in the preliminary and biological treatment rotating equipment such as the blower and pump. In addition, the energy consumption rate was higher to the order of 19.2% in the phosphorus removal process, 16.0% during sludge treatment, and 6.1% during disinfection and discharge. In terms of equipment energy usage, feeding and decanting pumps accounted for 40% of total energy consumed following 27% for blowers. By controlling the aeration rate based on the proposed feedback control system, the DO concentration was reduced by 56% compared pre-controls and the aeration amount decreased by 28%. The overall power consumption of the plant was reduced by 6% via aeration control.

• Journal of Korean Academy of Nursing Administration
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• v.7 no.2
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• pp.265-284
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• 2001

The case management has been applied to improve the quality of care and the cost-effectiveness in the most health care institutions. In a way of case management, the critical pathway(CP) has been executed in many acute care settings, focused on the diagnoses with high cost, high volume, and high risk. This study was conducted to develop a case management program using CP as an intervention of patients with lumbar spinal stenosis for the surgery of posterolateral fusion, and to find out the effects of the critical pathway on the quality of nursing care, patient satisfaction as an outcome of care, length of stay and medical charge, and nurses' job satisfaction. At the same time, patients' functional states were checked with the Oswestry Low Back Pain Index, to show that the CP would not decrease the patients' function compared to the control group. The subjects were 25 control patients with a usual operation of lumbar fusion and 25 experimental patients with CP. They were all female, aged $50s{\sim}70s$, admitted in the Orthopedic surgery ward of a university hospital. Also nurses on the floor using CP were asked to respond to measurement tool of job satisfaction before and after the application of CP, and compared with other nurses on the different wards. Data were analyzed with t-test for continuous variables and chi-square for non-parametric variables in addition to the reliability test of the measurement tools. The results of this study were as followings: 1. Patients' functional states The differences in Oswestry scores of the experimental and control groups assessed at preoperation and at discharge were not statistically significant. The change in scores of the experimental group measured at preoperation and at discharge was larger than that of the control group, however the difference was not statistically significant. The results indicate that the CP did not decrease the patients' functional status. 2. The quality of nursing care The total of quality of nursing care given to the experimental group was better than that of the control group(P=.000). In addition, the experimental group showed better scores of quality of every item of care than the control group(P=.000 -.004). 3. Patient satisfaction Patients of the experimental group were not more satisfied with general care than the control group. But they were more satisfied with discharge care of 'explanation about medication, body posture, and brace application' and 'explanation about the adjustment of daily living and exercise during recovery'(P= .047, P=.028). 4. Nurses' job satisfaction Nurses working with the CP showed more job satisfaction than before the CP introduction(P=.048). But the control group of nurses on a different floor showed no change in job satisfaction at the same period of time. 5. Length of stay and medical charge The mean length of stay of the experimental group was shorter than that of the control group without statistical significance. The charge of medication and treatment of the experimental group were smaller than that of the control group(P=.011, P=.000). The results of the study support that the case management using critical pathway enables to improve the quality of care and job satisfaction, to reduce the medical charge, and consequently to increase satisfaction with care. However, the case management should be instituted focusing on the quality improvement of nursing and the client satisfaction, not just for the purpose of cost-effectiveness of health care facilities.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.4
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• pp.1714-1720
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• 2012

The purpose of the study was to evaluation of the radiation dose reduction and the possibility of the maintainability of the adequate image quality using various automatic exposure control (AEC) systems in multi-detector computed tomography (MDCT). We used three AEC systems for the study: General Electric Healthcare (Auto-mA 3D), Philips Medical systems (DoseRight) and Siemens Medical Solutions (Care Dose 4D). The general scanning protocol was created for the each examination with the same scanning parameters as many as possible. In the various AEC systems, the evaluation of reduced-dose was evaluated by comparing to fixed mAs with using human phantom. The image quality of the phantom was evaluated with measuring the image noise (standard deviation) by insert regions of interests. Finally, when we applied to AEC for three manufacturers, the radiation dose reduction decreased each 35.3% in the Auto-mA 3D, 58.2% in the DoseRight, and 48.6% in the Care Dose 4D. And, there was not statistical significant difference among the image quality in the Strong/Weak of the Care Dose 4D(P=.269). This applies to variety of the AEC systems which will be very useful to reduce the dose and to maintain the high quality.

• Journal of Acupuncture Research
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• v.24 no.1
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• pp.79-98
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• 2007

Objectives : The study of Traditional Korean medical therapy has recently become a popular academic field as proven to be an great alternative to the limitation of Western medical treatment. However, there has been little study examining the Quality of life to investigate the Effectiveness of Recent Traditional Korean Medical Therapy on Treating Allergic Rhinitis. Thus, this study aims to reveal the characteristics of Allergic Rhinitis patients, their clinical symptoms, and other accompanying diseases. Moreover, it attempts to investigate the sense of improvement and satisfaction from the Allergic Rhinitis patients treated with Traditional Korean Medical therapy by examining Quality of Life Questionnaires. Subject and Method : A total of 380 subjects that consists of allergic rhinitis patients and non patients were participated in this study. 330 allergic rhinitis patients were divided into two groups; the experimental group (230 subjects) was treated with Traditional Korean Medical therapy, and the control group (100 subjects) was not treated with any other therapy. Also, the normal control group (50 subjects) who had no symptoms of the allergic rhinitis was participated in this study as well. All the subjects were asked to answer to the questionaries that consist of two parts such as recalling the symptoms that they had 3 month ago, and describing the current symptoms that they had the present. The experimental group also was asked to answer the quality of life questionnaire before and after the therapy. Results: The results of investigating recent Traditional Korean therapy are as follows: 1. The reservoir rate of other disease was 39.0% in the control group and 34.8% in the experimental group. These were higher than the rate of the normal control (10.0%), which reveals the clinical characteristics of allergic rhinitis patients. 2. The symptoms of Allergic Rhinitis showed improvement after Traditional Korean medical therapy, which can be shown by its statistical significance. (p=.000<.001). 3. 97.0% of the Allergic Rhinitis patients treated with the Korean Therapy answered the improvement of symptom within 4 weeks, and 88.3% of the patients were satisfied with the Traditional Korean medical therapy. 4. The Nasal symptoms had prominently positive effect at the most as the symptoms significantly affect sleep disturbances, ocular symptoms, activity limitation, and emotional problems.