• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.39 no.5
• /
• pp.8-15
• /
• 2002

We optimally designed the VCO(voltage-controlled oscillator) with spiral inductor using the MOSIS HP 0.5${\mu}{\textrm}{m}$ CMOS process. With the developed SPICE model of spiral inductor, the quality factor of spiral inductor was maximized at the operating frequency by varying the layout parameters, e.g., metal width, number of turns, radius, space of the metal lines. For the operation frequency of 2㎓, the inductance of about 3nH, and the MOSIS HP 0.5 CMOS process with the metal thickness of 0.8${\mu}{\textrm}{m}$, oxide thickness of 3${\mu}{\textrm}{m}$, the optimal width of metal lines is about 20${\mu}{\textrm}{m}$ for the maximum Quality factor. With the optimized spiral inductor, the VCO with LC tuning tank was designed, fabricated and measured. The measurements were peformed on-wafer using the HP8593E spectrum analyzer. The oscillation frequency was about 1.610Hz, the frequency variation of 250MHz(15%) with control voltage of 0V - 2V, and the phase noise of -108.4㏈c(@600KHz) from output spectrum.

• Safety and Health at Work
• /
• v.8 no.3
• /
• pp.237-245
• /
• 2017

Background: Solar furnaces are used worldwide to conduct experiments to demonstrate the feasibility of solar-chemical processes with the aid of concentrated sunlight, or to qualify high temperature-resistant components. In recent years, high-flux solar simulators (HFSSs) based on short-arc xenon lamps are more frequently used. The emitted spectrum is very similar to natural sunlight but with dangerous portions of ultraviolet light as well. Due to special benefits of solar simulators the increase of construction activity for HFSS can be observed worldwide. Hence, it is quite important to protect employees against serious injuries caused by ultraviolet radiation (UVR) in a range of 100 nm to 400 nm. Methods: The UV measurements were made at the German Aerospace Center (DLR), Cologne and Paul-Scherrer-Institute (PSI), Switzerland, during normal operations of the HFSS, with a high-precision UV-A/B radiometer using different experiment setups at different power levels. Thus, the measurement results represent UV emissions which are typical when operating a HFSS. Therefore, the biological effects on people exposed to UVR was investigated systematically to identify the existing hazard potential. Results: It should be noted that the permissible workplace exposure limits for UV emissions significantly exceeded after a few seconds. One critical value was strongly exceeded by a factor of 770. Conclusion: The prevention of emissions must first and foremost be carried out by structural measures. Furthermore, unambiguous protocols have to be defined and compliance must be monitored. For short-term activities in the hazard area, measures for the protection of eyes and skin must be taken.

• Journal of Preventive Medicine and Public Health
• /
• v.32 no.4
• /
• pp.473-481
• /
• 1999

Objectives: In recent days, the problem of odor pollution in community near Sihwa Industrial complex, Kynuggi Province is becoming of significant public concern. We have investigated the health effects of the Sihwa residents from odor pollution comparing with other less polluted areas. Methods: The Ansan and Kuri Cities were selected as control areas. The parents of the elementary and middle school students in these three areas were surveyed with structured questionnaire twice, Nov 1997 and Jure 1998 each. As a exposure index, the ambient air concentrations of five major air pollutants(particulates, $O_3,\;SO_2,\;NO_2$, CO) and subjective odor perception were used. We have focused health outcomes such as the prevalence of nonspecific irritant symptoms, respiratory disease among family members and the score of qualify of life(QOL). Results: Although the mean concentrations of major air pollutants except particulates were similar or lower in Sihwa than other areas, the odor perception rate and the monthly odor perception days were significantly higher. It suggested that odor producing chemical compounds are the major source of environmental pollution problem. There were higher prevalence rates of nonspecific irritant symptoms and respiratory disease among family members in Sihwa than other control areas. The QOL score was also lower in Sihwa. The odor perception proved to be a most important factor in reporting adverse health effects and lowering the QOL score. Conclusion: The residents living near Sihwa industrial complex were suffering from more adverse health symptoms and poorer QOL status than control areas. And it may be due to environmental odor pollution from industrial complex. Therefore, further research will be needed for monitoring of the responsible chemicals emitted from industries.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.33 no.2
• /
• pp.45-73
• /
• 2008

Quality has long been considered as an important factor in creating competitive advantage, and researches on quality have not been limited to off-line products but actively extended to e-services and information goods. However, given the nature of multi-dimensional aspect of quality, the systematic study on the quality of online service is still in its early stage. Especially, studies on the quality of ASP services have been rare in academic and professional journals despite the growth of ASP industry in its size and the rapid expansion in the range of application. In this paper we clarified the multi-dimensional quality aspects of the ASP service using a Garvin's framework (1984) which encompasses the service aspects of Products, and developed a measurement model for ASP service qualify. Then we empirically tested the effects of ASP service quality on user satisfaction and perceived firm performance using the data from 240 Korean small firms with less than 50 employees that had experienced the ASP service. Our results show that there are positive relationships among ASP service quality and personal performance, user satisfaction and perceived firm performance, and that product and service-related aspects of ASP service exert differential effects on performance measures so that the product-related aspects of the ASP service such as performance, features, reliability and conformance are considered to be more important in evaluating benefits from ASP services. Contrary to the approaches In literature where only the quality of online services is evaluated, our results emphasize the importance of differentiating Product and service-related aspects of ASP service and provide a basis for more comprehensive evaluation of ASP service quality.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.18 no.8
• /
• pp.1102-1107
• /
• 1993

Microwave dielectric properties of CaTiO3 and CaTiO3-TiO2 ceramics for the composition range between 40 and 50 mol% CaO in CaO-TiO2 binary system were investigated. CaTiO3 ceramics with50 mol% CaO showed the dielectric constant (e,) of 178, the temperature coefficient of resonant frequency(c,) of+1000 ppm/'c and the qualify factor Q of 2760 (f0=2.7 GHz ). Dielectric constant and temperature coefficient of resonant frequency of ceramics with dual phases of CaTiO3 and TiO2 decreased gradually from those of CaTiO3 as the CaO content decreased. Q value and density were found to have minimum at the composition of 47 mol% CaO. The degradation of Q value and density in dual phase ceramics seems to be caused by the large pores at grain boundaries and/or within grains remained after rapid growth of CaTiO3 grains as TiO2 Phase decreased.

• The Journal of Korean Academic Society of Nursing Education
• /
• v.5 no.2
• /
• pp.191-205
• /
• 1999

The purpose of this study is to identify the influence of family support on hope of the patients with stroke. Subjects were 53 in-patients with stroke in two general hospitals and one oriental medicine hospital located in Seoul and Kwang-Ju. The instruments used for this study : The family support scale developed by Kang Hyun Suk(1985). The hope scale developed by Nowotny(1989). The Data were analyzed with descriptive statistics, t-test, ANOVA. Pearson's correlation and simple regression. Data had been collected from December 24, 1998 to January 31, 1999. The results of this study were as follows The mean score of family support was 43.94 and the mean score of the hope was 80.89. The relationship between family support and the hope of the patients with stroke revealed a significant correlation (r= .560, p= .0001). The variables influencing family support and the hope of the patients with stroke were as follows : There was significant difference between family support and general characteristic factor, which was family chief caregiver (p= .002). There was no significant difference between hope and general characteristic factors. but There were significant differences between one of the subscales of hope, 'confidence in the outcome' and general characteristic factors, which were age(p= .021), perceived disability effect(p= .027). There were significant differences between one of the subscales of hope 'possibility of future', and general characteristic factors, which were age(p= .016), education(p= .018). There was significant difference between one of the subscales of hope. 'spiritual belief', and general characteristic factors, which was religion(p= .002). There was significant difference between one of the subscales of hope, 'active involvement', and general characteristic factors, which was family chief caregiver (p= .012). It was found that the higher the degree of perceived family support, the higher the degree of hope. Clearly, the perceived family support can contribute significantly and positively to hope of the patients with stroke. Therefore, nurses should plan interventions to inspire hope level of patients with stroke by family support. The above results may be used as the basic data to seek more efficient way of elevating nursing practice and qualify for the patients with stroke.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.18 no.1
• /
• pp.30-37
• /
• 2005

The microwave dielectric properties and their related structural characteristics in solid solutions of (1-$\chi$) Ba($Mg_{1/3}$Nb$_{2/3}$) $O_3$-$\chi$La(Mg$_{2/3}$Nb$_{1}$3) $O_3$(BLMN) have been investigated by measuring the dielectric constant($\varepsilon$r), Q value and temperature coefficient of resonant frequency($\tau$f) and by observing the crystal structure using high resolution transmission electron microscopy (HRTEM). Microwave dielectric properties showed characteristic features for specific composition. Dielectric constant($\varepsilon$$_{r}$) showed maximum value at the composition which corresponds to the phase boundary between 1 : 2 ordered and 1 : 1 ordered structure. The increase in $\varepsilon$$_{r}$ may be caused by the rattling of ions by incorporating smaller ions and the disordered structure. The variation of temperature coefficient of resonant frequency($\tau$$_{f}$) was investigated in terms of oxygen octahedra tilting.dra tilting.

• Journal of the Korean Society of Food Culture
• /
• v.20 no.2
• /
• pp.283-291
• /
• 2005

This study was peformed by questionnaire to investigate satisfaction for the menu qualify of Korean traditional food of Japanese tourists. The subjects of this study consisted of 280 Japanese tourists using the Gyeongju and Busan hotel. The results were summarized as follows: 63.9% of the subjects responded that frequency of visiting was 1-2 times a year and 42.1% responded that motivation of visiting was for tour and understanding of korea. Companion with friend scored high as 40.4%, and intention of revisiting was high on 'normal'. On overall satisfaction on korean traditional foods, 'satisfy' scored high as 43.2%. 61.1% of the subjects responded that the taste was the most important factor of food. On frequency of eating, 'over 8 times' scored high as 27.9%, and on motivation of eating, 'with visiting Korea' scored high as 48.2%. On satisfaction for the menu quality of korean traditional food, the highest item was 'taste(3.82 point)' and 'nutrition(3.82 point)', and but 'Japanese mark on menu(2.47 point)', 'Japanese mark on ingredient(2.61 point)' scored low. Overall satisfaction for korean traditional food had an effect on intention of revisiting, and therefore, improving the quality of the traditional food and the strategy for the classification of desires are earnestly requested.

• Journal of the Korean Society of Food Culture
• /
• v.13 no.5
• /
• pp.423-430
• /
• 1998

The purposes of this study were to (a) measuring attitude and satisfaction of Yonsei university students towards contracted vs. rented university foodservices, (b) determine university students' overall satisfaction & perception regarding the factors improved towards university foodservice and (c) provide recommendation on marketing strategies for university foodservices. Questionnaires were hand delivered to 600 Yonsei University students by designated coordinators. A total of 549 questionnaires were usable; resulting in an 93% response rate. The survey was conducted between October 12 to October 18, 1995. Statistical data analysis was completed using the SAS Programs for descriptive analysis, T-test, ${\chi}^2-test$, ANOVA, Factor Analysis and Stepwise Multiple Regression. The results of this study can be summarized as follows: 1. Performance mean score for contracted foodservice management in terms of food, menu, price, hygiene, facilities was higher than for rented foodservice management. 2. The average satisfaction score for contracted foodservice management in terms of price was lower than for rented foodservice management. There was no gap between contracted foodservice management and rented foodservice management in overall satisfaction score and price satisfaction score. 3. Perception regarding the factors improved of thirteen factors to be improved except operating hours, waiting time, price, food quantity were perceived as better by students. 4. Perception regarding the factors improved have correlation with foodservice qualify attribute's performance. 5. According to multiple regression analysis, 92.05% of the variance in respondents' satisfaction score could be explained by procedure after meal, purchasing procedure, operating hours, availability of breakfast, waiting time, atmosphere, price, facilities, service endeavor to survey satisfaction in foodservice, availability of kitchen and wall space, portion size, taste of food, change of cafeteria name, the number of seats, and variety of menu.

• The Journal of Korean Society for Radiation Therapy
• /
• v.6 no.1
• /
• pp.154-170
• /
• 1994

The Purpose of this study was to determine the degree and contents composing the qualify of life and to analyze the relationships among the demographic characteristics, the degree of pain and the quality of life of the cancer patients experiencing a radiation therapy. The subjects for this study were 110 out-patients experiencing a radation therapy at C University Hospital in K-city, from April to October, 1992. The data were obtained using a convenience sampling technique. The tool of this study was the quality of life scale developed by Ro, You-Ja and the data were analyzed using a SAS program for percentages, mean & standard deviation. ANOVA and Scheffe test. The results were as follows : 1. the average total score of the quality of life of the subjects was 139.65(minimum score 121-maximum score 164), item mean score grange 1-5) was 2.97. For each factor in the quality of life scale, the mean scores (range 1-5) were 3.29 in emotional state, 3.14 in relationship with neighbors. 3.04 in physical state and function. 2.92 in self-esteem, 2.81 in economic life and 2.65 in relationship with family. 2. The incidence of physical symptoms was seen fatigue ($84.5\%$). anorexia ($65.5\%$) and weight loss ($47.3\%$) in order. The 50.9 percentage of the subjects complained of moderate or severe pain. 3. The results of the analysis of the relationships between the demographic variables and the quality of life were as follows : Gender (F=8.45, P=0.0044), age (F=6.29, P=0.0001). educational level (F=5.67, P=0.0046), marital status (F=6.82. P=0.0016), occupation (F=2.86, P=0.009), monthly income (F=6.90, P=0.0003), family living together (F=3.95, P=0.0494) and person paying a medical fee (F=5.14, P=0.0023). 4. The relationship between the degree of pain and the quality of life was significant difference (F=3.12, P=0.0482).