• Journal of the Korean Ceramic Society
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• v.49 no.5
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• pp.475-483
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• 2012

High capacitance X5R MLCCs based on $BaTiO_3$ ceramic dielectric layers exhibit a single broad, asymmetric arc shape impedance and modulus response over the wide frequency range between 1 MHz to 0.01 Hz. Analysis according to the conventional brick-layer model for polycrystalline conductors employing a series connection of multiple RC parallel circuits leads to parameters associated with large errors and of little physical significance. A new parametric impedance model is shown to satisfactorily describe the experimental spectra, which is a parallel network of one resistor R representing the DC conductivity thermally activated by 1.32 eV, one ideal capacitor C exactly representing bulk capacitance, and a constant phase element (CPE) Q with complex capacitance $A(i{\omega})^{{\alpha}-1}$ with ${\alpha}$ close to 2/3 and A thermally activated by 0.45 eV or ca. 1/3 of activation energy of DC conductivity. The feature strongly indicate the CK1 model by J. R. Macdonald, where the CPE with 2/3 power-law exponent represents the polarization effects originating from mobile charge carriers. The CPE term is suggested to be directly related to the trapping of the electronic charge carriers and indirectly related to the ionic defects responsible for the insulation resistance degradation.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.7071-7076
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• 2015

Epidermal growth factor receptor (EGFR) is one of the targeted molecular markers in many cancers including lung malignancies. Gefitinib and erlotinib are two available therapeutics that act as specific inhibitors of tyrosine kinase (TK) domains. We performed a case-control study with formalin-fixed paraffin-embedded tissue blocks (FFPE) from tissue biopsies of 167 non-small cell lung carcinoma (NSCLC) patients and 167 healthy controls. The tissue biopsies were studied for mutations in exons 18-21 of the EGFR gene. This study was performed using PCR followed by DNA sequencing. We identified 63 mutations in 33 men and 30 women. Mutations were detected in exon 19 (delE746-A750, delE746-T751, delL747-E749, delL747-P753, delL747-T751) in 32 patients, exon 20 (S786I, T790M) in 16, and exon 21 (L858R) in 15. No mutations were observed in exon 18. The 63 patients with EFGR mutations were considered for upfront therapy with oral tyrosine kinase inhibitor (TKI) drugs and have responded well to therapy over the last 15 months. The control patients had no mutations in any of the exons studied. The advent of EGFR TKI therapy has provided a powerful new treatment modality for patients diagnosed with NSCLC. The study emphasizes the frequency of EGFR mutations in NSCLC patients and its role as an important predictive marker for response to oral TKI in the south Indian population.

• Journal of the Korean Society of School Health
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• v.2 no.1
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• pp.48-57
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• 1989

To evaluate the college students' health status, the author distributed C.M.I. to 233 college students consisting of 102 males and 131 females who randomly selected from a college in seoul. The conclusion are as follow: 1. The mean of CMI scores for the male students was 32.84 and that for the female students was 43.25. Statistical significant difference was observed between the mean of CMI scores for male students and that for female students. 2. For male students, The CMI mean scores for the day students was 29.46 and for evening students was 35.85. There was no statistical significant difference the day students and that for the evening students. 3. For female students, the mean of CMI scores for day students was 42.40 and that for the evening students was 44.64. But there was no statistical significant difference between the mean CMI scores for the day students and that for the evening students. 4. In both female and male groups, the affirmative response rate of inadequacy, fatigability and eyes and ears are higher than any of the other items. 5. In comparing the CMI items of male students and female students, the significant differences cardiovascular system, musculoskeletal system, skin, nervous system, genitourinary system, fatigability, habits, inadequacy, depression and tension. The mean scores for female students, with the exception of habits, were higher than those for male students. 6. In comparing the CMI items of male day students and male evening students, there was significant difference in the items of the cardiovascular system, digestive tract, skin, genitourinary system, inadequacy, and anger : the mean scores of evening male students were higher than those of day students. 7. In the case of female students, the CMI mean scores of the evening students in the categories eyes and ears, cardiovascular system, digestive tract, musculoskeletal system, skin, genitourinary system, fatigability, inadequacy, depression, anxiety, and sensitivity were higher scores than those of the day students. However, the were no significant difference between both groups except in the cathgory of habits. 8. The frequency rate of neurotic students, who were identified by fukamachi's classification, were 12.5% in the day male students, 18.6% in th evening male students, 13.6% in the day female students, and 18.0% in the evening female students.

• Journal of Environmental Health Sciences
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• v.46 no.4
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• pp.376-387
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• 2020

Objectives: This study is aimed at offering basic data for making plans for offensive odor management after researching offensive odor occurrence and characteristics in Gangwon Province. Methods: The data used in the study is based on offensive odor data analyzed by the Gangwon Institute of Health and Environment from 2012 to 2019. The data were reclassified by year, month, facility, and region to identify characteristics of occurrence. Finally, a distribution map of offensive odors was created using ArcGIS. Results: The highest monthly frequency of offensive odor occurrence falls in June, August, and July, and the summer season and third quarter are the highest. According to the latest eight-year data for Gangwon Province, complaints about offensive odors in county areas are more frequent than those in city areas. There are many offensive odor complaints in Wonju, Cheorwon, and Heongsung. The main offensive odor emission facilities are livestock and waste treatment (recycling) facilities. Complaints about offensive odors are relatively lower the Yeongdong area than Yeongseo area, which is considered to be the result of characteristics of land-sea breezes and geographical factors. Offensive odors from livestock facilities count for an average of 53.9% of the total, and the inadequacy rate of livestock facilities averages 36.9%. Conclusions: To maintain a clean environment in Gangwon Province, it is strongly recommended that an offensive odor reduction plan for livestock facilities be established. Areas with a high density of offensive odor occurrence should be identified and systematically managed with short- and mid-term measures. If offensive odors is managed using GIS, it is possible to identify the characteristics of occurrence by time and space and also by facility. In addition, since systematic data management is possible, it is believed that a rapid response to offensive odors, prediction of their spread, and efficient management are possible.

• Journal of Society of Preventive Korean Medicine
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• v.19 no.3
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• pp.29-43
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• 2015

Objective : The purpose of this study was to identify characteristics of patients' self-perceived health in traditional Korean medical facilities. Method : This research was conducted based on the survey on patients whom have visited traditional Korean medical facilities in 2011 by the Ministry of Health and Welfares and Korean Institute for Health and Social Affairs. Using a sample of 3,931 (1,180 male and 2,751 female) outpatients' self-perceived health based on the data from usage and consumption of Korean Medicine. 'Healthy', 'Fair', and 'Poor Health' were used to measure patients' self-perceived health status. The data was analyzed by frequency, t-test, cross correlation analysis and multiple logistics regression analysis using the SPSS program package. Results : Sex(P<0.001), age(P<0.001), marital status(P<0.001), education(P<0.001), employment status(P<0.001), occupation(P<0.001), health insurance(P<0.001) and income level(P<0.0001) showed statistical significance. Main Treatment Facilities(P<0.001), experience of taking Korean medicine(P=0.032), experience of receiving acupuncture treatment(P<0.001), number of visits(P<0.001), medical expense (P=0.005), and subjective health status after the treatments showed statistical significance for Korean herbal medicine(P=0.038), acupuncture (P=0.001), cupping therapy(P=0.006), oriental physiotherapy(P=0.003), and treatment satisfaction(P<0.001). For subjective health status based on suffering disorders in the past three months, the response of poor health was higher in the group suffering recent illnesses. Statistical significance was seen in hypertension (P=0.002), arthritis(P<0.001), lumbar pain(P<0.001), diabetes mellitus(P=0.001), stroke(P<0.001), hwa-byung (P=0.001), gastric disorders(P=0.021), common cold(P<0.001), ankle sprain(P<0.001), muscular injury(P<0.001), lumbar sprain(p=0.009) and fracture(P=0.03). Also the number of diseases during the past three months showed statistical significance(P<0.001). Statistical significance was also seen in Level of knowledge(P<0.001), route of information(P<0.001), reliability of Korean medicine(P=0.003), insurance coverage(P=0.005), medical costs(P<0.001), and future willingness to use Korean medicine(P<0.001). As a result of the multiple logistics regression analysis, risks of subjective poor health statistically increased in female population, elderlies, medicaid beneficiaries, less educated, higher medical expense, and more disorders during the past three months. Conclusion : Patients' self-perceived health status has significant differences with each variables such as sex, age, marital status, education, health insurance, medical expense, number of diseases.

• Journal of Periodontal and Implant Science
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• v.29 no.1
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• pp.51-63
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• 1999

Exposure of the root surface due to gingival recession after periodontal surgery, elicit pain response when exposed to mechanical, heat, chemical or osmotic irritation. Especially patients treated with periodontal surgery, show high frequency. There have been reports that the 1 out of 7 patients complains of dentinal hypersensitivity. There have been many studies on the clinical effects of various materials on the treatment of dentinal hypersensitivity. The purposes of this study were to evaluate the effect of sodium chloride and potassium oxalate and to observe the relationship between the dentinal hypersensitivity and surface characteristics such as dentinal tubule size and number. This study included 20 teeth which were scheduled for extraction and had no pulpal disease. These teeth were divided into Root planing group, EDTA group, NaCl group and Oxalate group. Dentinal hypersensitivity is measured by tactile, pressured air and cold water using NRS (Numerical Rating Scales). Teeth were extracted under local anesthesia and each specimen was sectioned to a size about 3 X 5 mm and was examined under the scanning electron microscope (X2,000) The results were as follows, 1. The EDTA group exhibited significantly increased dentinal hypersensitivity comparing with the other groups. 2. The NaCl and Oxalate groups showed significantly reduced dentinal hypersensitivity comparing with the EDTA group. 3. As a method for dentinal hypersensitivity measurement, it was presumed thet tactile sensitivity test was not sensitive method but air blast test and cold water test were adequate method. 4. In a SEM study, the root planing group exhibited amorphous smear layer and showed no dentinal tubule orifice, but the EDTA group showed the large number of dentinal tubules. On the other hand, the NaCl and Oxalate groups did not show exposed dentinal tubules. The NaCl group showed more rough root surface than the EDTA group, and the Oxalate group showed many participates to be presumed as calcium oxalate particle. As the results from this study, root planing couldn't expose the dentinal tubule and NaCl and potassium oxalate occluded exposed dentinal tubule effectively. Dentinal hypersensitivity has close relationship with the exposure of dentinal tubules, especially with it's size and number.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.2 s.344
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• pp.27-38
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• 2006

When an RFID reader attempts to read tags, interference might occur if the neighboring readers also attempt to communicate with the same tag at the same time or the neighboring readers use the same frequency at the same time. These interferences cause the RFID reader collision. When the RFID reader collision occirs, either the command from the reader can not be transmitted to the tags or the response from the tags can not be received by the reader correctly. RFID reader anti-collision algorithms have been developed to reduce it. One of the best blown reader anti-collision algorithms is the Colorwave algorithm proposed by MIT. The Colorwave algorithm reduces the reader collisions by having the readers operate at different times. In Colorwave the time is divided into frames and a frame is divided into a number of slots. Each reader can access the tags using the slot time assigned to it. Depending on the probability of the interference, the colorwave adjusts the frame size to improve the efficiency. In this paper, we analyze the operations and the performance of the Colorwave algorithm and identify the problems of the algorithm. We also show that by adding some modifications to the algorithm the performance can be improved significantly.

• Korean Journal of Animal Reproduction
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• v.20 no.4
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• pp.379-384
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• 1997

Superovulation with exogenous gonadotropins creates a spectrum of pre or periovulatory hormonal changes with subsequent detrimental effects on oocyte quality, fertilization, embryo development, implantation and maintenance of pregnancy. Our recent study determined potential roles for insulin-like growth factor-1 (IGF-1) in uterine environment regulation and preimplant tation in the rat. The evidence indicates that IGF-l may play an important role in the main tenance of a receptive uterine environment for embryonic development and the regulation of decidualization. Embryonic loss and failure of implantations following superovulation may be partially attributed to disturbances in uterine IGF-l action as observed in this study. We investigated the effects of superovulatory doses of gonadotropins on frequency of chromosomal a abnormalities of mouse embryos. Chromosome a analysis of mouse zygotes and 8- to 16-cell stage embryos from spontaneously ovulated, 5, 10, and l 15 lU pregnant mare serum gonadotropin (PMSG) superovulated mice was carried out. Aneuploidy, polyploidy and structural chrom- osomal abnormalities were detected among the four groups. However, only polyploidy was correlated with superovulation. In 10 and 15 IV PMSG treated groups, the rate of polypoidy was 2.9% and 10.5%, respectively. Furthermore, there was a dose reponse relationship between the PMSG dose and the incidence of embryonic p polyploidy (P

• Korean Journal of Occupational Health Nursing
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• v.6 no.2
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• pp.156-167
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• 1997

In Korea, based on the Revised Law of Occupational Safety and Health a new entity of institution was set up in 1990 to provide occupational health services to SSE in which three sorts of personnel as a team have to be involved. These institutions, in charge of scores to hundreds of workplace area-wide, have been providing occupational health services without payment from employers or employees, and government reimburses through the Occupational Injury Prevention Insurance since 1993. As a service provider, a team is composed of doctors, nurses and industrial hygienists. Undergraduate and postgraduate educations for the SSE occupational health are not specified and the question on the performance of the personnel has been raised. This study was designed to analyze the facilitating factors of and barriers to the performance and its improvement of these personnel. In 1997, the survey was conducted with all 58 institutions. Structured questionnaires were mailed to 200 personnel who were providing the occupational health service for SSE. The response rate was 51.7% for doctors, 58.6% for nurses, and 60.3% for industrial hygienist, respectively. Results are as follows : 1) There is a guideline for occupational service mandated by the government. Under the guideline, the minimum frequency of visiting workplace is assured with six times of doctors, 17 times for nurse and industrial hygienist in a year. There are one doctor for every 200 factories, one nurse and one hygienist for every 100 factories. 2) All respondents have basic qualification for occupational health service. About 16.7%. of doctors are certified in industrial medicine or preventive medicine, and 64.7% of industrial hygienists had first grade certification. Totally 66.7% of personnel have been involved in occupational health for more than one year. 3) As a support system for the performance improvement, 66.3% respond that they have been provided with educational materials, advice related to industrial environment and guidance of MSDS from Korea Industrial Safety Corporation. Most respondents indicate the lack of concern of employers and employees as a main barrier to the improvement of the service. Also they are in the need of the training opportunity more focused on SSE. The Governments policy for SSE is a principal facilitating factor. Training program focused on SSE situation, manpower, technical support, etc. are areas to be improved to have a better occupational health service for SSE in Korea.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.8
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• pp.128-135
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• 2013

This paper presents a high dimming ratio Power-LED driver IC with high power which is capable of controlling LEDs. In order to accomplish a high dimming ratio LED driver, the preloading inductor current methodology is proposed for the power stage of the proposed method to achieve the fast transient response time during the Power-LED load switching. The information containing the current flowing on the LEDs can be utilized to predict the amount of the current on the inductor. The minimum LED current rising time of existing high dimming ratio Power-LED driver is limited by $3{\mu}s$, however that of the proposed high dimming ratio Power-LED driver is reduced about 1/10. The LED driver is implemented with 0.35um 60V BCDMOS 2-poly 4-metal process. The measurement results show that the proposed LED driver system features the minimum rising time as small as 240ns at the dimming frequency of 1KHz with a 12V of input voltage, nine white LEDs and 353mA of LED current. The LED rising time and power conversion efficiency of the chip are measured to be 240ns and 93.72%, respectively.