• Journal of Environmental Analysis, Health and Toxicology
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• v.21 no.4
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• pp.281-291
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• 2018

Recently, long-range atmospheric transport (LRAT) from China is regarded as a major reason for elevated levels of particulate matter (PM) in Korea. However, local emissions also play an important role in PM pollution, especially in large-scale industrial cities. In this study, PM samples were collected at suburban, residential, and industrial sites in Ulsan, Korea. Polycyclic aromatic hydrocarbons (PAHs) and heavy metals were analyzed, and a potential human health risk assessment was conducted. The concentrations of PAHs and heavy metals in total suspended particles (TSP) increased during high $PM_{10}$ episodes, and backward trajectory analysis verified the influence of LRAT from China during the high episodes. Furthermore, the concentrations of PAHs and heavy metals in $PM_{2.5}$ and $PM_{10}$ at the industrial site were higher than those at the residential site. The risk assessment of PAHs and heavy metals in $PM_{2.5}$ suggested no significant health effects. The highest levels of PAHs were measured in the particle size of $0.32{\sim}0.56{\mu}m$ at the residential site, and those of heavy metals were detected in the particle size of 1.8~5.6 and $>18{\mu}m$, reflecting different major emissions sources for both groups. On the basis of this preliminary study, we are planning long-term monitoring and modeling studies to quantitatively evaluate the influence of industrial activities on the PM pollution in Ulsan.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.7
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• pp.671-678
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• 2017

In this paper, we conducted an industry input-output analysis to examine the impact of the advertising industry on the movie industry. As a result, the production inducement effect increased from 1993 to 2008, and it decreased from 2009 to 2012. In 2014, the production inducement effect increased to 0.028 won. Value added effect is found that it fluctuated yearly. As a result of the sensitivity coefficient of the advertising industry, it decreased increasingly. In the case of the influence coefficient for backward linkage effect, it showed a decreasing tendency after 1998, but it increased from the beginning of 2009. This study examines the influence of the advertising industry on the input of the output by analyzing the impact of the advertising industry on the movie industry. As a follow-up study, it is necessary to compare the impact of the advertising industry on the movie industry and other industries such as publishing and broadcasting.

• Journal of Korean Academy of Nursing
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• v.21 no.2
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• pp.129-149
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• 1991

Circadian rhythm is entrained in the 24-hour time interval by periodic factors in the environment, known as zeitgeber. But most rotating work schedules are outside the range of the entrainment of the pacemaker timing the human circadian sleep - wake cycle. It has been postulated that physiological and emotional disturbances occur in most human functions when the circadian rhythm is disturbed. So application of circadian principles to the design of shift schedules can aid in maintaining the temporal integrity of the circadian system and thereby minimize for the shift worker any detrimental consequences of circadian disruption. This study was a quasi-experimental study to test the effect of shift intervals for the clinical nurse on the circadian rhythm. Twenty nurses newly employed in general units of two hospitals were selected as an experimental group and twelve college nursing students as a control group. Both groups were selected according to an established criteria using a purposive sampling technique. Ten subjects were assigned to a weekly shift group and another ten to a biweekly shift group engaged in a semi -continuous shift schedule(sunday off) with a backward direction, that is, morning -evening - night shift. The control group worked a morning shift for 42 days. Oral temperature rhythm, waking tim, sleep - wake cycle, fatigue, and mental performance were measured during the experimental period. The data collection period was from April 30, 1990 to June 10, 1990. MANOVA, paired t-test, ANOVA, and Student Newman Keuls method were used for statistical analysis. The results are summarized as follows. 1. Phase delay in the acrophase of temperature rhythm was shown according to the backward rotating shift. A complete adaptation to work on the night shift was achieved between the sixth and ninth day of the night shift. 2. There was no difference in either waking time or sleep- wake cycle according to the duration of the working day for every shift group. Significant difference was found in the waking time and the sleep -wake cycle for subjects on the morning, evening, and night shift in both of the shift groups(weekly shift group : λ＝0.121, p＜0.01, λ＝0.112, p＜0.01, biweekly shift group : λ＝0.116, p＜0.01, λ＝0.084, p＜0.01). 3. There was no difference in fatigue between the first working day and the last working day for the control group and for the biweekly shift group. In the weekly shift group, physical fatigue was significantly different for the first day and the sixth day of the night shift(t＝-2.28, p＜0.05). Physical fatigue and total fatigue on the first day of the night shift showed a significant difference among the control group, the weekly shift group, and the biweekly shift group(F＝5.79, p＜0.01, F＝4.56, p＜0.05). There was a significant difference between the shift groups and the control group(p＜0.05), Physical fatigue, neurosensory fatigue and total fatigue on the last day of the night shift showed a significant difference among the control group, the weekly shift group, and the biweekly shift group(F＝12.65, p＜0.01, F＝7.77, p＜0.01, F＝9.68, p＜0.01). There was a significant difference between the shift groups and the control group(p＜0.05). 4. No difference in mental performance was seen between the first day and the last day of work in each case. An arithmatic test on the first day of the night shift revealed a significant difference among the control group, the weekly shift group, and the biweekly shift group(F＝3.79, p＜0.05). There was a significant difference between the shift groups and the control group(p＜0.05) . The digital symbol substitution test and the arithmetic test on the last day of the night shift showed a significant difference among the control group, the weekly shift group, and the biweekly shift group(F＝3.68, p＜0.05, F＝5.55, p＜0.01), and both showed a significant difference between the shift groups and the control group(p＜0.05). Accordingly, this study showed that during night duty, the waking time, sleep- wake cycle, and fatigue increased and mental performance decreased compared with morning and evening duty. It was also found that the weekly shift group had a higher fatigue score on the sixth day of night duty as compared to the -first day, but the waking time, sleep- wake cycle, and mental performance revealed no difference for the duration of the night duty or between shift groups, and complete adaptation of temperature rhythm was achieved between the sixth and ninth day of night duty. It is possible to conclude from these results that for intermediate circadian type in a healthy young woman, a biweekly shift system is more compatible with the circadian timing system than weekly shift system.

• Korean Journal of Social Welfare
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• v.61 no.3
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• pp.77-101
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• 2009

As a case study in the field of policy implementation research, this study focuses on how the logic of consumer choice and provider competition operates on the front line of policy processing. To find the implementation process of the program, 39 interview data were analyzed, including voucher users, care workers, social workers in 4 agencies and local public officers in one of the district in Seoul, and relevant officials from the Ministry for Health, Welfare and Family affairs and the Center for Social Service Management. The main results are as follows: In the level of policy implementation, user choice and competition, which was the main logic behind the implementation of the voucher program, did not occur as expected by policy makers. Instead of user choosing his/her provider, it was found that the providers were choosing its users. Secondly, the case study found that providers have formed a caucus which allocated the local users equally amongst the providers. In this process, local public officers have supported the meeting by providing them with a list of users. Such results may be interpreted as a habitual execution from the tradition of supply-side subsidy, rather than the way of implementation in the market system. Thirdly, although voucher users could not choose their preferred agency in the first stage of service, some other choices exists so that users may choose their preferred care-giver and time for service. Finally, the change of agency and care-giver in the way of delivering services were observed.

• Journal of Environmental Science International
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• v.29 no.1
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• pp.55-68
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• 2020

The purpose of this study is to investigate the relationship of fine dust PM₁₀ and heavy metals in PM₁₀ in Asian dust flowing into Gwangju from 2013 to 2018. The migration pathways of Asian dust was analyzed by backward trajectory analysis using HYSPLIT (Hybrid Single Particle Lagrangian Integrated Trajectory) model, and the change of heavy metal concentration and heavy metal content per 1 ㎍/㎥ of fine dust PM₁₀ in Gwangju area were analyzed. Also, the characteristics of the heavy metals were analyzed using the correlation between the heavy metals in PM₁₀. As a result of analyzing Asian dust entering the Gwangju region for 6 years, the average concentration of PM₁₀ measured in Asian dust was 148 ㎍/㎥, which was about 4.5 times higher than in non-Asian dust, 33 ㎍/㎥. A total of 13 Asian dust flowed into the Gwangju during 6 years, and high concentration of PM10 and heavy metals in that were analyzed in the C path flowing through the Gobi/Loess Plateau-Korean Peninsula. As a result of the correlation analysis, in case of Asian dust, there was a high correlation between soil components in heavy metals, so Asian dust seems to have a large external inflow. On the other hand, in case of non-Asian dust, the correlation between find dust PM₁₀ and artificial heavy metal components was high, indicating that the influence of industrial activities in Gwangju area was high.

• Korean Journal of Applied Biomechanics
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• v.17 no.2
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• pp.113-121
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• 2007

The purpose of this study was to determine the effect of three different plates($0^{\circ}$, $10^{\circ$}, $20^{\circ}$)under heels on the lower limb muscles and erector spinae during squat exercise. Ten high school korean traditional wrestling players(age: $18.5{\pm}0.7$, weight: $1972.2{\pm}128.5N$, height: $177.8{\pm}6.0cm$, weight of barbell: $1004.5{\pm}132.4N$) performed squat exercise using three different tilting plates under heels at a cadence of 40beats/sec with 80% one repetition maximum load. Surface electrodes were placed on the participants' left and right erector spinae, and rectus femoris, vastus medialis, vastus lateralis, tibialis anterior, biceps femoris, medial gastrocnemius, and lateral gastrocnemius in the right lower extremity. One S-VHS camcorder(Panasonic AG456, 60fields/s) was placed 10m to the side of the participant. To synchronize the video and EMG data, a synchronization unit was used for this study. Average and Peak IEMG values were determined for each participant. For each variable, a one-way analysis of variance was used to determine whether there were significant differences among three different tilting plates under heels. When a significant difference was found in plates type, post hoc analyses were performed using the Tukey procedure. A confidence level of p<.05 was used to determine statistical significance. As a result of this study, maximum nEMG values of the tibialis anterior in $0^{\circ}$ plates was significantly higher than the corresponding values for the other plates during the knee extension. This increased activation in the tibialis anterior muscle indicates an increase in displacement of center of gravity of body. It is very likely that additional muscle activation are needed to stop the forward and backward movement. The results also showed that muscular activities of quadriceps femoris and erector spinae were decreased with increasing angle of plates. This suggests that increasing angle of plate may help to sustain the balance and posture of squat exercise. It is considered that very few significant differences were found among three different plates($0^{\circ}$, $10^{\circ}$, $20^{\circ}$) since elite players with much experience in squat exercise, were chosen as a participant of this study. In order to obtain meaningful results regarding the tilting angle of heel plates in squat exercise, kinetic and 3D kinematic analysis will be needed in the future study.

• Korean Journal of Veterinary Service
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• v.31 no.4
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• pp.497-504
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• 2008

A cross-sectional study was undertaken to report prevalence and to identify risk factors of subclinical mastitis of dairy cattle in Sylhet district of Bangladesh. Among 325 dairy farms of the district 12 farms(3.7%) were selected conveniently for this study. All the dairy cows of the 12 farms were selected for sample collection. Fresh milk samples from each of the selected dairy cows were collected aseptically in separate sterilized test tube as RF, RH, LF and LH quarter of the udder. Rapid modified White Side Test(WST) was used to detect subclinical mastitis(SCM). Results of WST and data derived from filled in questionnaire were entered in Microsoft Excel 2003 and transferred to $STATA^{(R)}$, version 8.0/Intercooled(Stata Corporation, Texas, USA, 2003). The overall prevalence of SCM and its distribution in different categories of variables in cow and their exact binomial 95% confidence intervals were calculated in $STATA^{(R)}$. Simple bivariable associations among independent variables were investigated by $x^2$ test in $STATA^{(R)}$. Multiple logistic regression analysis with backward elimination method was used to identify risk factors of SCM. To identify significant variation in quarter SCM, linear regression analysis was performed after arcsine transformation of the data. The overall prevalence of SCM found in this study is 54%. Dairy cows with teat lesions had significantly increased SCM(OR=12342, P value=0.000, 95% CI=762, 199798) than others without teat lesions. The Holstein Friesian X Jersey X Sahiwal breed has significantly decreased(OR=0.18, p=0.03, 95% CI 0.04, 0.85) SCM than other breeds. The prevalence of SCM found in this study is in agreement with others. The injury in the teat increases the probability of getting infected with microbes and thereby mastitis. If the prevalence of teat lesion can be decreased the probability of subclinical mastitis will also be decreased. The negatively associated Holstein Friesian X Jersey X Sahiwall breed may help in planning mastitis control program if this finding can be validated by a more powerful case-control or cohort study design.

• Journal of Korea Port Economic Association
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• v.29 no.1
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• pp.77-97
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• 2013

This paper focuses upon the relationship between port and port city. The purpose of this study is to theoretically review the relationship between port and its city, and to identify crucial policy directions for mutual development of port and the backward city in the case of Gwangyang Port (GP), Korea. The contents of this paper consist of five main sections: introduction; a concept of port-port city relationship; an analysis of the relationship between GP and its city; policy directions for GP city; conclusion. This study was mainly conducted by a literature review of the papers/reports and the analysis of secondary data. Significant policy strategies are associated with development of value-added logistics, expansion of additional port business, vitalization of port hinterlands, and establishment of port logistics clusters in terms of port economic function. Green port operation, improvements of coastal environment, establishment of port waterfronts, and conceptual port redevelopment master plan are included in the major port city development strategies in terms of sustainable development. Another major port city development strategies contain major port city master plan, institutional arrangements for port city development, specialized port city development policy, and formation of free trade port city in relation to integrated port-port city planning and management.

• Journal of the Korean Geotechnical Society
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• v.29 no.12
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• pp.11-24
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• 2013

This study presents a design method for typical rainfall-induced landslide considering in-situ matric suction. Actual landslide data are used to validate the proposed method. The soil-water characteristic curve (SWCC) and unsaturated permeability are experimentally determined to estimate hydraulic properties of testing site. The field measurement of matric suction is carried out to monitor in-situ matric suction in a natural slope subjected to rainfall infiltration, which is incorporated in the landslide analysis. The wetting band depth and safety factor of the slope are assessed to clarify the effect of domestic rainfall pattern. Especially, the effect of antecedent rainfall on the slope stability is investigated and discussed in terms of wetting band depth using parametric study. It is found from the result of this study that proposed design method can consider the characteristic of unsaturated soil and effect of antecedent rainfall. The location of the scarp zone is fairly well predicted by proposed design method. Moreover, heavy rainfall, concentrated in the backward part with time, causes the lowest safety factor of the slope. These results demonstrate that decrease in matric suction due to antecedent rainfall may trigger slope instability. After the antecedent rainfall, additional rainfall may cause the slope failure due to increasing wetting band depth.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.1
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• pp.131-138
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• 1998

In order to minimize the trial frequency in the new filter cigarette design, we studied the relationship between smoke yield and tipping materials of cigarette. A three levels full factorial design involving filament denier (X1,2.5-3.3d), Porosity of the acetate filter plug wrap (X2, 3,500-16,000CU) and porosity of the tip paper (X3, 400-1,200CU) was used. Three independent factors (Xl, X2, X3) were chosen for their effects on the various responses and the function was expressed in terms of a quadratic polynomial equation, Y : $\beta$o + $\beta$1Xl + $\beta$2X2 + $\beta$3X3 + $\beta$11Xl2 + $\beta$22X22+ $\beta$33X32 + $\beta$12X1X2 + $\beta$13XIX3 $\beta$23X2X3 which measures the linear, quadratic, and interaction effects. Twenty-nine trial numbers were obtained as a results of using a three levels full factorial design and it was analyzed by the multiple regression analysis with backward stepwise in STATISTICA/pc under restricted conditions. Tar yields of the cigarette was affected by porosity of tip paper (0.66), filament denier (0.47) and porosity of plug wrap (0.28) in the decreasing order, and linear effect of tip paper porosity (B3) and filament denier (91) were significant at a level of 0.01($\alpha$). The filament denier and tipping paper porosity interaction F ratio among three factors had a P-value of 0,000041, indicating higher interaction between these factors. Based on the analysis of variance, the model fitted for Tar (Y1) was significant at 5% confidence level and the coefficient of determination (0.96) was the proportion of variability in the data fitted for by the model.