• Journal of Environmental Health Sciences
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• v.41 no.1
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• pp.24-29
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• 2015

Objectives: The objective of this study was to identify determine factors for blood VOCs levels in college students. Methods: Venous blood samples were collected from healthy 29 male and 25 female volunteers. The samples were analyzed with solid-phase microextraction gas chromatography and mass spectrometry. Results: Blood concentrations of benzene, toluene, ethylbenzene, m-,p-xylene, o-xylene were higher in smoking group than in non-smoking group. Geometric means of smoking group and non-smoking group were 0.45 and $0.36{\mu}g/L$ in benzene, 0.82 and $0.47{\mu}g/L$ in toluene, 0.44 and $0.41{\mu}g/L$ in ethylbenzene, 0.49 and $0.39{\mu}g/L$ in m-,p-xylene and 0.47 and $0.43{\mu}g/L$ in o-xylene, respectively. Gender, alcohol drinking, coffee, commuting time (30 minutes) by a car and adjacency between home and road were not associated with increasing blood VOCs concentrations of college students. Conclusion: Smoking habit was significantly associated with blood concentrations of benzene, toluene, ethylbenzene, o-,m-,p-xylene in college students.

• Journal of the Korean Institute of Intelligent Systems
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• v.11 no.5
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• pp.406-412
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• 2001

In this paper, a new fuzzy single layer learning algorithm is proposed, which shows improved learning time and convergence property than that of the conventional fuzzy single layer perceptron algorithms. First, we investigate the structure of physiological neurons of the nervous system and propose new neuron structures based on fuzzy logic. And by using the proposed fuzzy neuron structures, the model and learning algorithm of Physiological Fuzzy Single Layer Perceptron(P-FSLP) are proposed. For the evaluation of performance of the P-FSLP algorithm, we applied the conventional fuzzy single layer perceptron algorithms and the P-FSLP algorithm to three experiments including Exclusive OR problem, the 3-bit parity bit problem and the recognition of car licence plates, which is an application of image recognition, and evaluated the performance of the algorithms. The experimentation results showed that the proposed P-FSLP algorithm reduces the possibility of local minima more than the conventional fuzzy single layer perceptrons do, and enhances the time and convergence for learning. Furthermore, we found that the P-FSLP algorithm has the great capability for image recognition applications.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.7
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• pp.1554-1560
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• 2015

802.11p WAVE is the next-generation wireless communication that can make Ad-hoc network communication possible for Vehicle-to-Vehicle. GBSR protocol, one of the 802.11p WAVE protocols, mainly focuses on improvements in networks that have a tendency to disconnect. However, it does not consider the transmission time and velocity of a packet thus, there is a disadvantage of there being a delay in the transmission velocity, in urgent situations like car accidents, emergency patients transportation and crimes. In this paper, we proposed A-GBSR protocol for transmission of a packet to mobile node which has a high speed through the improved beacon message and Adaptive Neighbor list Management that are considering of the GBSR protocol transmission velocity.

• Women's Health Nursing
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• v.6 no.1
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• pp.34-45
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• 2000

The study was to find whether the educational program contributed to increase of knowledge and self-efficacy of the postpartal primiparas. This study aimed at improvement of the educational effect for postpartal primiparas. The Subjects were 34 primiparas who were admitted to the obstetric ward in a University hospital from November 15th to December 9th, 1999. The Subjects were those who had no labor pain at the admission time, had no complications during labor and delivery and, gave birth to a healthy baby. They were tested on knowledge and self-efficacy two times, one at the admission time and prior to discharge. After the first test nurses in a maternity ward taught them on postpartal care. Two tools were developed by authors based on literature review. The test tool fr knowledge of postpartal car consisted of 23 items. The test tool for self-efficacy of postpartal care consisted of 16 items. Analysis of demographic data were analyzed with calculation of percentage. Score differences between the first test and the second test were analyzed with paired t-test. The Spss (Win 8.0) program was used for data analysis. The results are as follows. 1. There were not significant influencing general characteristics of primiparous to pre-educational knowledge. There were significant influencing general characteristics of primiparous to post-educational knowledge : occupation(t=13.04, p=0.00), postpartal education(t=5.51, p=0.02). 2. There were not significant influencing general characteristics of primiparous to pre-educational self-efficacy. There were significant influencing general characteristics of primiparous to post-educational self-efficacy : antenatal education(t=5.53, p=0.02) 3. Primiparas' knowledge of postpartal care increased significantly after education(t=13.04, p=0.00). 4. Primiparas' self-efficacy of postpartal care increased significantly after education(t=5.51, p=0.02). 5. Correlation between knowledge and self-efficacy was r=.360(p=0.03). We suggest follow-up studies to find whether primiparas' self-efficacy will last after discharge or not.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.1
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• pp.49-56
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• 2010

Objective: To investigate assisted reproductive technology (ART) outcomes in women with WHO class I anovulation compared with control group. Design: Retrospective case-control study. Methods: Twenty-three infertile women with hypogonadotropic hypogonadism (H-H) who undertook ART procedure from August 2003 to January 2009 were enrolled in this study. A total of 59 cycles (H-H group) were included; Intra-uterine insemination with super-ovulation (SO-IUI, 32 cycles), in vitro fertilization with fresh embryo transfer (IVF-ET, 18 cycles) and subsequent frozenthawed embryo transfer (FET, 9 cycles). Age and BMI matched 146 cycles of infertile women were collected as control group; 64 cycles of unexplained infertile women for SO-IUI and 54 cycles of IVF-ET and 28 cycles of FET with tubal factor. We compared ART and pregnancy outcomes such as clinical pregnancy rate (CPR), clinical abortion rate (CAR), and live birth rate (LBR) between the two groups. Results: There was no difference in the mean age ($32.7{\pm}3.3$ vs. $32.6{\pm}2.7$ yrs) and BMI ($21.0{\pm}3.1$ vs. $20.8{\pm}3.1kg/m^2$) between two groups. Mean levels of basal LH, FSH, and $E_2$ in H-H group were $0.62{\pm}0.35$ mIU/ml, $2.60{\pm}2.30$ mIU/ml and $10.1{\pm}8.2$ pg/ml, respectively. For ovarian stimulation, H-H group needed higher total amount of gonadotropin injected and longer duration for ovarian stimulation (p<0.001). In SO-IUI cycles, there was no significant difference of CPR, CAR, and LBR between the two groups. In IVF-ET treatment, H-H group presented higher mean $E_2$ level on hCG day ($3104.8{\pm}1020.2$ pg/ml vs. $1878.3{\pm}1197.7$ pg/ml, p<0.001) with lower CPR (16.7 vs. 37.0%, p=0.11) and LBR (5.6 vs. 33.3%, p=0.02) and higher CAR (66.7 vs. 10.0%, p=0.02) compared with the control group. However, subsequent FET cycles showed no significant difference of CPR, CAR, and LBR between the two groups. Conclusion: H-H patients need higher dosage of gonadotropin and longer duration for ovarian stimulation compared with the control groups. Significantly poor pregnancy outcomes in IVF-ET cycles of H-H group may be due to detrimental endometrial factors caused by higher $E_2$ level and the absence of previous hormonal exposure on endometrium.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.1
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• pp.72-81
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• 2015

Objectives: The aim of this study was to investigate the exposure and risk assessment of residents near asbestos mines in Korea. Methods: To assess asbestos types and airborne concentrations, air monitoring was performed in the neighborhoods of Kwangcheon (KC) and Sinsuk (SS) mines, which were leading South Korean mines in the past. In addition, activity-based-sampling (ABS) of residents' particular activities were conducted in order to estimate the Excess Lifetime Cancer Risks (ELCRs) for the residents. Conclusions: The average concentration of airborne asbestos in KC was 0.0014 f/cc and 0.0015 f/cc by PCM and TEM, respectively. In SS it was equal at 0.0012 f/cc by PCM and TEM. No statistically significant difference was found in the average concentration of airborne asbestos between the two mines. The average asbestos concentration of ABS was 0.0048 f/cc (PCM) and 0.0042 f/cc (TEM) in KC, while it was 0.0137 f/cc (PCM) and 0.0125 f/cc (TEM) in SS. It was found that the average asbestos concentration of ABS in SS was statistically significantly higher than that of KC (p<0.01). The results of ELCRs by scenario in KC showed that the scenarios of bicycle, car, weed control, weed whacking, child playing in the dirt, and physical training fell within $1{\times}0^{-6}-1{\times}10^{-4}$, which is the acceptable range of ELCR. The scenarios of motorcycle, walker, digging, and field sweeping, however, exceeded the acceptable range. In SS, only the scenario of car fell within the acceptable range, while all of the other scenarios exceeded the acceptable range.

• Journal of Environmental Health Sciences
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• v.27 no.1
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• pp.20-26
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• 2001

personal nitrogen dioxide(NO$_2$) exposures for 31 professional drivers were measured using passive sampler and time activity diary in Asan and Chunan area, and were estimated using time-weighted average model. Mean concentrations of driver’s indoor and outdoor were 24.7$\pm$10.7 ppb and 23.3$\pm$8.3 ppb, respectively with indoor/outdoor of 1.1. Mean personal NO$_2$ exposure was 30.3$\pm$9.7 ppb. Personal NO$_2$ exposures were strongly correlated with indoor car NO$_2$ levels ($R^2$=0.80) rather than residential indoor NO$_2$ level ($R^2$=0.55). and outdoor NO$_2$ level ($R^2$=0.50). The driver’s NO$_2$ exposure using LP-gas with 24.4$\pm$8.0 ppb were statistically different from those using diesel with 36.3$\pm$14.1 ppb(p<0.01). The effect of driver’s smoking for personal NO$_2$ exposure was not found. It was considered that the main NO$_2$in driver is transportation. Since drivers mostly spent their times in indoor and inside car, time-weighted average model could be used to estimated personal NO$_2$ exposure using time activity diary, Though we did not measure all microenvironments, the estimated personal NO$_2$ exposures with 26.9$\pm$10.2 ppb were statistically correlated with measured personal NO $_2$ exposures30.3$\pm$9.7 ppb ($R^2$=0.89). The mean and standard deviation of personal NO$_2$ exposure using Mote-Carlo simulation were 26.6$\pm$7.2 ppb.

• Journal of Korean Society on Water Environment
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• v.26 no.4
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• pp.622-628
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• 2010

In this study, Solid-phase microextraction (SPME) with GC/FID was studied as a possible alternative to liquid-liquid extraction for the analysis of BTEX and MTBE. Experimental parameters affecting the SPME process (such as kind of fibers, adsorption time, desorption time, volume ratio of sample to headspace, salt addition, and magnetic stirring) were optimized. Experimental parameters such as CAR/PDMS, adsorption time of 20 min, desorption time of 5 min at $250^{\circ}C$, headspace volume of 50 mL, sodium chloride (NaCl) concentration of 25% combined with magnetic stirring were selected in optimal experimental conditions for analysis of BTEX and MTBE. The general affinity of analytes to CAR/PDMS fiber was high in the order p-Xylene>Toluene>Ethylbenzene>MTBE>Benzene. The linearity of $R^2$ for BTEX and MTBE was from 0.970 to 0.999 when analyte concentration ranges from $30{\mu}g/L$ to $500{\mu}g/L$, respectively. The relative standard deviation (% RSD) were from 2.5% to 3.2% for concentration of $100{\mu}g/L$ (n=5), respectively. Finally, the limited of detection (LOD) observed in our study for BTEX and MTBE were from $7.5{\mu}g/L$ to $15{\mu}g/L$, respectively.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.5
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• pp.121-129
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• 2013

To find a healthy driving posture, in this study, survey and empirical analysis given onto measurement of car-seat angle has been performed. Among 153 male respondents, those drivers who has minimum 5 year experience and 2 hours daily driving has been selected by a multiple screening process. They were further confirmed to have no discomfort history in any body region caused by the driving task. Final 44 people verified that their actual driving posture is not significantly different (p = 0.692) from healthy one they think. And their data, accordingly, the healthy driving postures are clustered based on the same seat-cushion angle, seat-back angle and trunk-thigh angle. Consequently, three seat-angles of the 44 subjects showed a significant difference only with their height information which is the most effecting factor on driving posture among the physical characteristics. That is a first result categorized healthy driving posture classified physical, if it were departmentalized into additional study, could be able to reflected a factor of "healthy" on car seat design.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.152.1-152.1
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• 2011

We report preliminary results of long-slit near-infrared (NIR) spectroscopy of Luminous Blue Variables (LBVs) with moderate resolution of R ~ 2400. We obtained Jshort (1.04-1.26 micron) and Ks (2.02-2.31 micron) band spectra of 4 LBVs and 3 LBV candidates in Southern hemisphere using IRIS2, infrared imager and spectrograph, mounted on the 4-m Anglo-Australian Telescope. All targets are fairly bright in NIR so that we can obtain high signal-to-noise ratio for clear line detection and modeling. They are also widely distributed in the HR diagram so that we can compare the spectral properties of LBVs in different temperature and luminosity ranges. Among them, we present the results of two well-known LBVs AG Car and HR Car. Their spectra show similar properties with hydrogen, He I, and metallic lines such as Fe II and Mg II, most of them in emission. We discuss, in particular, the He I 1.083 micron lines formed in stellar wind because these two LBVs show large variation in their He I line intensities, compared to previous studies. Since the He I 1.083 line is known to be anticorrelated with the photometric variation of LBVs, strong line intensities with P-Cygni profiles in both stars indicate that they are now near the visual minimum phase. We model the obtained spectra using non-LTE atmosphere code CMFGEN of Hillier (1998) to derive stellar parameters such as wind velocity and mass loss rate, and discuss the long-term variability of stellar parameters of these LBVs. deduced from our otometric solution.