• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.343-343
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• 2002

This study examines the influence of long-range transport of dust particles and air pollutants on both local/regional DMS oxidation chemistry and the distribution of sulfur compounds at Jeju Island (33.17$^{\circ}$ N. 126.10$^{\circ}$ E) during the Asian dust-storm(ADS) period in April 2001. The atmospheric concentrations of these sulfur species were measured at a ground station on Jeju Island. Korea as Part of the ACE-Asia intensive operation. Three ADS events were observed during the periods of 10-12, 13-14. and 25-26 April. respectively. The concentrations of DMS and CS$_2$ were higher during the ADS period than during the non-Asian-dust-storm (NADS) period. Conversely. a difference in SO$_2$ levels during the ADS period was not distinguishable from those during the NADS period. The diurnal variation pattern of DMS observed was largely different from that in the remote marine boundary layer. DMS loss by NO$_3$ in the atmospheric boundary layer was dominant due to significantly high NOx levels influenced by the long-range transport of pollutants from East Asia to Jeju Island The DMS maximum during the ADS period was observed in the late afternoon. The oceanic fluxes of DMS during the ADS and NADS periods were estimated to be 5.7$\pm$2.3 and 2.9 (+2.8/-1.5) mole m$^{-2}$ day$^{-1}$ . respectively. The contribution of oxidized DMS to SO$_2$ levels at Jeju Island during the study period was found to be insignificant.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.429-429
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• 2002

This study examines the influence of long-range transport of dust particles and air pollutants on photochemistry of OH and NO$_3$ at Jeju Island (33.17$^{\circ}$ N, 126.10$^{\circ}$ E) during the Asian dust-storm (ADS) period in April 2001. The atmospheric concentrations of criteria pollutants (O$_3$, NO$_2$, CO) and sulfur species were measured at a ground station on Jeju Island, Korea as part of the ACE-Asia intensive operation. Three ADS events were observed during the periods of 10-12, 13-14, and 25-26 April, respectively. The concentrations of the criteria pollutants (i.e., $O_3$, NO$_2$, and SO$_2$) were not significantly different from those during the non-Asian-dust-storm (NADS) period. Average OH and NO$_3$ levels at Jeju Island during the study period (ADS and NADS) were estimated to be 4-10 $\times$ 10$^{5}$ moleculescm$^{-3}$ and 2-4 pptv, respectively. Two main sources of OH radical were the primary production from the reaction of water vapor ($H_2O$) and O(1D) radicals and the reaction of HO$_2$ with NO. CO was a dominant sink of OH during the ADS period: whereas NO$_2$ was the most important during the NADS period. for NO$_3$ radical, a reaction of NO$_2$ with $O_3$ was the most important atmospheric source; while $N_2$O$_{5}$ uptake on dust particles was the most dominant sink during the ADS period.

• Bulletin of the Korean Chemical Society
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• v.35 no.9
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• pp.2863-2866
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• 2014

• Journal of Yeungnam Medical Science
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• v.4 no.1
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• pp.105-121
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• 1987

The authors studied anxiety-depression using New Anxiety-Depression Scale(NADS), in the subjects of 3,499male and 1,335 female college freshmen of Yeungnam University. The authors collected the reports of NADS during the periods from January to February, 1986, and applied ANOVA and t-test on anxiety-depression scores in order to compare them between various psychosocial factors, and sexs. The results are as follows : There was significant difference in the mean awerages of total scores between male and female students: male students scored $31.49{\pm}6.57$ female students scored $33.37{\pm}6.84$ (P<0.001) The anxiety-depression scores relating to the items of sleep disturbance, apprehension, decreased libido and fatigue were relatively higher in both groups. Ninety-nine male students(2.8%) showed seriously high degree anxiety-depression scores of 50 or higher, while forty female students(3.0%) showed the same scores. There was a strong tendency toward higher anxiety-depression scores in the students who were dissatisfied with their home atmosphere, colleges, departments and familiarity of parents, and those who had pessimistic views of self image in the past, present, or fartare in both groups (P<0.001) The students whose maturation locations were below city level, showed higher level of anxiety-depression scores in both groups (P<0.05) NADS and SAS, SDS, and Leeds scale were correlated significantly in 0.64, 0.61, and 0.77 of correlation coefficient.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.E3
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• pp.137-148
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• 2003

In this study, we examined the influence of long-range transport of dust particles and air pollutants on the photochemistry of NO$_3$on Jeju Island, Korea (33.17 N, 126.10$^{\circ}$E) during the Asian Dust-Storm (ADS) period of April 2001. Three ADS events were observed during the periods of 10∼12, 13∼14, and 25∼26 April. Average concentration level of nighttime NO$_3$on Jeju Island during the ADS period was estimated to be about 2 x 10$^{8}$ molecules cm$^{-3}$ ( - 9 pptv). Decreases in NO$_3$levels during the ADS period was likely to be determined mainly by the enhancement of the $N_2$O$_{5}$ heterogeneous reaction on dust aerosol surfaces. The reaction of N20s on aerosol surfaces was a more important sink for nighttime N03 during the ADS due to the significant loading of dust particles. The reaction of $N_2$O$_{5}$ with NMHCs and the gas-phase reaction of N20s with water vapor were both significant loss mechanisms during the study period, especially during the NADS. However, dry deposition of these oxidized nitrogen species and a heterogeneous reaction of NO$_3$were of no importance. Short-term observations of $O_3$, NO$_2$, DMS, and SO$_2$in the MBL indicated that concentrations of most of these chemical species were different between the ADS and non - Asian - Dust-Storm (NADS) periods, implying that their levels were affected sensitively by the differences in air mass trajectories.

• Journal of Yeungnam Medical Science
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• v.9 no.1
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• pp.54-67
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• 1992

The author studied the mental status of 497 patients admitted in non-psychiatric wards and 42 patients diagnosed as mental disorders by DSM-III-R criteria and admitted in three general hospitals located in Pusan city, using NADS and PSCS. The assessment were obtained from October, 1991 to March, 1992 and the results as follows: The mean ${\pm}$ SD of Anxiety-Depression scores were $34.4{\pm}10.4$ in non-psychiatric patients and $50.0{\pm}18.3$ in psychiatric patients. The psychiatric group had significantly higher scores than non-psychiatric group. The mean ${\pm}$ SD of Psychosis scores were $3.9{\pm}4.4$ in non-psychiatric patients and $20.3{\pm}9.8$ in psychiatric patients. The psychiatric group had significantly higher scores than non-psychiatric group. In the psychosocial factors, dissatisfaction in family atmosphere and acquaintanceship with parellts(P<0.001, relatively), pessimistic in future, present and past self-images(P<0.001, relatively), and yes in previous psychiatric treatment of admission(P<0.01, relatively) had common significant relationships to Anxiety-Depression and Psychosis scores. There were correlationships between NADS scores and PSCS scores(${\gamma}$ = 0.74), past and present self-images(${\gamma}$ = 0.45), present and future self images(${\gamma}$ = 0.45), past and future self-images(${\gamma}$ = 0.34) and family atmosphere and acquaintanceship with parents(${\gamma}$ = 0.49). The regression analysis revealed that present self-image, acquaintanceship with parents, future self-image, past self-image, and family atmosphere, in order of significance were to be descriptive or predicable variances for Anxiety-Depression status. The discriminant analysis according to Anxiety-Depression scores showed that the cases of incorrect classification were 22 for non-psychiatric patient group and 2 for psychiatric patient group.

• Journal of Yeungnam Medical Science
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• v.4 no.2
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• pp.29-38
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• 1987

The authors studied anxiety-depression using New Anxiety-Depression Scale (NADS) in the subjects of 2.564 male and 1,252 female college freshmen of Yeungnam University. The authors collected the reports of NADS during the periods from January to February 1987, and applied NAOVA and t-test on anxiety depression scores in order to compare them between various psychosocial factors and sexes. The results are as follows : There was significant difference in the mean average of total scores between male and female students : male students scored $33.41{\pm}8.76$ and female students scored $35.34{\pm}9.02$ (P<0.001). The anxiety-depression scores relating to the items of sleep disturbance, apprehension, facial flushing and fatigue were relatively scored higher in both groups. One hundred and thirty nine male students (5.4%) showed seriously higher degree of anxiety-depression scores of 50 or more, while eighty eight female students (7.0%) showed the sane scores. There was a strong tendency toward higher anxiety-depression scores in the students who were dissatisfied with their home atmosphere, colleges, departments, familiarity of parents am those who had pessimistic views of self image in the past, presents and future in both groups (P<0.001).

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.04a
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• pp.600-605
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• 2012

In this paper, the acoustic performance of a shipboard large-sized room unit is studied. The room unit is a kind of rectangular absorptive chamber with a partition whose surface absorptive material with fabric skin is attached to. The room unit has one inlet and three outlet. At the inlet, a plane damper is installed to control the flow rate. The acoustic performance of a prototype room unit is measured using a HVAC mock-up. It is shown that its insertion loss is comparable with that of a commercially-used room unit but the developed room unit generates flow noise higher than the other one. The major source of flow noise is analyzed by NADS-R, the noise analysis program for room unit. Cone-shaped dampers are proposed to be used as the damper of a room unit to reduce flow noise. It is shown that the cone-shaped damper decrease flow noise remarkably.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.5
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• pp.468-473
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• 2012

In this paper, the acoustic performance of a shipboard large-sized room unit is studied. The room unit is a kind of rectangular absorptive chamber with a partition whose surface absorptive material with fabric skin is attached to. The room unit has one inlet and three outlets. At the inlet, a plane damper is installed to control the flow rate. The acoustic performance of a prototype room unit is measured using a HVAC mock-up. It is shown that its insertion loss is comparable with that of a commercially-used room unit but the developed room unit generates flow noise higher than the other one. The major source of flow noise is analyzed by NADS-R, the noise analysis program for room unit. Cone-shaped dampers are proposed to be used as the damper of a room unit to reduce flow noise. It is shown that the cone-shaped damper decrease flow noise remarkably.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.5
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• pp.561-568
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• 2014

The Republic of Korea Army is using R-NAD of MIL-STD-188-220 as a Media Access Control protocol. Under urgent situations, almost all stations transmit data frames and then the network will reach a saturation state. Several articles have been devoted to the study of R-NAD performance. However, most of them focus on comparing the performance of some NADs using network simulation tools. We propose an analytical model to compute the throughput of R-NAD under the assumption of a network traffic saturation. Analytical results were verified by Monte Carlo methods. We have shown that the performance of a success probability and an average idle time remains almost unchanged as the total number of stations increases. We have also shown that Type 1/2/4 operation mode outperforms Type 3 operation mode in throughput. The results showed that the system with a squelch detection achieved a better performance than the one without it. The longer DATA time had a higher throughput.