• Title/Summary/Keyword: boundary characteristics

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Seasonal fluctuations and changing characteristics of a temperate zone wetland bird community

  • Lee, Soo-Dong;Kang, Hyun-Kyung
    • Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.104-116
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    • 2019
  • Background: The composition of wild bird populations in temperate zones greatly varies depending on phenological changes rather than other environmental factors. Particularly, wild birds appearing in wetlands fluctuate greatly due to the crossover of species arriving for breeding during the summer and for wintering. Therefore, to understand the changes to species composition related to phenology, we conducted this basic analysis of populations to further the cause of the protection of wetland-dependent wild birds. Methods: It is wrong to simply divide a wild bird population investigation into seasons. This study identifies species composition and indicator species that change along with seasons. Wetlands to be surveyed are protected by natural monuments and wetland inventory and are in a state close to nature. In order to identify as many species as possible in wetlands, a survey was conducted in both shallow and deep wetlands. The water depth varied in these areas, ranging from 0.2 to 2.0 m, allowing for both dabbling and diving ducks to inhabit the area. Surveys were conducted using line-transect and distance sampling methods and were conducted at intervals of 2 weeks. The survey was conducted under the following three categories: the eco-tone and emergent zone, the submergent zone, and the water surface. The survey was conducted along a wetland boundary by observing wild birds. A PC-ord program was used for clustering, and the SAS program was used to analyze the changes in species composition. The data strongly indicates that day length is the main factor for seasonal migration periods, despite the fact that climate change and increasing temperatures are often discussed. Results and conclusions: The indicator species for determining seasons include migrant birds such as Ardea cinerea, Alcedo atthis, Anas penelope, and Poiceps ruficollis, as well as resident birds such as Streptopelia orientalis and Emberiza elegans. Importantly, increases in local individual counts of these species may also serve as indicators. The survey results of seasonal fluctuations in temperate zones shows that spring (April to June), summer (July to September), autumn (October), and winter (November to March) are clearly distinguishable, even though spring and summer seasons tend to overlap, leading to the conclusion that additional research could more clearly identify fluctuation patterns in species composition and abundance in the study area.

Effects of Low-Dose Fractionated Total Body Irradiation on Murine Immune System (마우스에서 전신 저선량 분할 방사선 조사에 의한 면역학적 변화 평가)

  • Kim, Mi-Hyoung;Rhu, Sang-Young;Lim, Dae-Seog;Song, Jie-Young
    • Journal of Radiation Protection and Research
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    • v.39 no.3
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    • pp.134-141
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    • 2014
  • Along with the wide use of radiotherapy in cancer treatment, there is growing interest in beneficial effect of low-dose irradiation (LDI) in cancer therapy. Therefore, we investigate how LDI affects immune responses in mice model. Total body irradiation (TBI) on C57BL/6 mice was given at low-dose rate of $1mGy{\cdot}min^{-1}$ using $^{137}Cs$ source at three times for consecutive three days. Hematological examination, total cell numbers of spleen, populations and characteristics of splenocytes were determined. Total numbers of RBC or platelet in irradiated mice showed no significant changes. WBC counts were decreased in a dose-dependent manner 2 days after TBI, however, these differences are gradually waned until 28 days. Dose-dependent decrease in the number of splenocytes of TBI mice at day 2 was also improved as time progressed. While the level of Foxp3 mRNA was decreased, the frequency of $CD4^+$ T cells and $CD69^+$ cells in spleen was increased at day 2 and 14. Fractionated low-dose TBI on mice exhibited normal body weight with no distinguishable behavior during whole experimental periods. These results suggest that some parameters of immune system could be altered and evaluated by fractionated low-dose TBI and be used to broaden boundary of low dose radiation research.

Articulatory Attributes in Korean Nonassimilating Contexts

  • Son, Minjung
    • Phonetics and Speech Sciences
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    • v.5 no.1
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    • pp.109-121
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    • 2013
  • This study examined several kinematic properties of the primary articulator (the tongue dorsum) and the supplementary articulator (the jaw) in the articulation of the voiceless velar stop (/k/) within nonassimilating contexts. We examined in particular the spatiotemporal properties (constriction duration and constriction maxima) from the constriction onset to the constriction offset by analyzing a velar (/k/) followed by the coronal fricative (/s/), the coronal stop (/t/), and the labial (/p/) in across-word boundary conditions (/k#s/, /k#t/, and /k#p/). Along with these measurements, we investigated intergestural temporal coordination between C1 and C2 and the jaw articulator in relation to its coordination with the articulation of consonant sequences. The articulatory movement data was collected by means of electromagnetic midsagittal articulometry (EMMA). Four native speakers of Seoul Korean participated in the laboratory experiment. The results showed several characteristics. First, a velar (/k/) in C1 was not categorically reduced. Constriction duration and constriction degree of the velar (/k/) were similar within nonassimilating contexts (/k#s/=/k#t/=/k#p/). This might mean that spatiotemporal attributes during constriction duration were stable and consistent across different contexts, which might be subsequently associated with the nontarget status of the velar in place assimilation. Second, the gestural overlap could be represented as the order of /k#s/ (less) < /k#p/ (intermediate) < /k#t/ (more) as we measured the onset-to-onset lag (a longer lag indicated shorter gestural overlap.). This indicates a gestural overlap within nonassimilating contexts may not be constrained by any of the several constraints including the perceptual recoverability constraint (e.g., more overlap in Front-to-Back sequences compared to the reverse order (Back-to-Front) since perceptual cues in C1 can be recovered anytime during C2 articulation), the low-level speech motor constraint (e.g., more overlap in lingual-nonlingual sequences as compared to the lingual-lingual sequences), or phonological contexts effects (e.g., similarity in gestural overlap within nonassimilating contexts). As one possible account for more overlap in /k#t/ sequences as compared to /k#p/, we suspect speakers' knowledge may be receptive to extreme encroachment on C1 by the gestural overlap of the coronal in C2 since it does not obscure the perceptual cue of C1 as much as the labial in C2. Third, actual jaw position during C2 was higher in coronals (/s/, /t/) than in the labial (/p/). However, within the coronals, there was no manner-dependent jaw height difference in C2 (/s/=/t/). Vertical jaw position of C1 and C2 was seen as inter-dependent as higher jaw position in C1 was closely associated with C2. Lastly, a greater gap in jaw height was associated with longer intergestural timing (e.g., less overlap), but was confined to the cluster type (/kp/) with the lingual-nonlingual sequence. This study showed that Korean jaw articulation was independent from coordinating primary articulators in gestural overlap in some cluster types (/k#s/, /k#t/) while not in others (e.g., /k#p/). Overall, the results coherently indicate the velar stop (/k/) in C1 was robust in articulation, which may have subsequently contributed to the nontarget status of the velar (/k/) in place assimilation processes.

A Study on the Male Images shown in the Music Videos Costumes -Focused on the Music Videos produced between 2000 and 2002- (뮤직비디오 의상에 나타난 남성 이미지 연구 -2000년부터 2002년 현재까지-)

  • Do, Heuy;Yang, Sook-Hi
    • Journal of the Korean Society of Costume
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    • v.54 no.3
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    • pp.27-42
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    • 2004
  • Music videos provide for many others images, alluring the audience to fall in another emotional world, while the sexual images shown in them suggest new images of man and woman. Today, men's images are being interpreted from various viewpoints. As interests in men's fashion are visualized through music video clothing, not only juveniles who want to be identified with the music video images but also adults try to imitate them, and proceed to wear the clothing, obliterating the boundary between 'reality' and 'illusion' and creating new images of men. This study is aimed at reviewing the male images shown in the music videos, particular their clothing, produced between 2000 and 2002. The results of this study could be summarized as follows : 1. Since beginning of the human history, men's image has been characterized by patriarchal system, capitalism, bourgeois class which emerged after industrial revolution and other man-dominant socio-cultural phenomena, such male image are shown in the music video as conservative and dominant image. 2. However, due to the post-modern culture, the power began to be decentralized. while feminism and men's liberation movement gain strength. As a result, women or heterosexuals began to regard men as sexual objects, and such a phenomenon is featured as sexual, bisexual or decadent images in the music videos. 3. On the threshold of the 21st century, music videos have begun to creatively describe men's life, their social conflicts, dreams and hopes and death and thereby. feature men's such images as being destroyed in view of existentialism. The numerous creative men's images interpreted in this way are featured in many music video works only to create playful, cyborg or demonic images using the senses. After all, men's images are featured in the music video costumes in diverse ways ranging from the conventional images to acquiescent images. In addition, various male images are combined with the characteristics of the music videos to be re-created anew. The young men in the our modern age tend to imitate or apply such images to create their own images or individualistic styles. All in all, men's image can be fixed no longer but diversified and fragmented in the new age.

A Field Survey of Noise Associated with Subway Train Passage (지하철 연도변의 소음 조사)

  • Son Jung Gon
    • Explosives and Blasting
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    • v.11 no.2
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    • pp.60-68
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    • 1993
  • The noise and vibration generated by the subway rolling stocks operated along the Seoul Subway Line No.1, 2, 3, and 4 lead to a controversy of pollution problem especially in residential areas. However, there is no data or guide to define the damage or provide adequate protection against such pollutions. The field measurements were made to characterize the noise attenuation due to distance, noise level distribution around the subway track of the aboveground and underground parts of each Line. The assessment criteria and methods are considered in addition to the practical available noise control methods. The noise level measured at Line No. 1 and 3 are less than 60 dB(A) with no pollution problem. Only a part of the aboveground section of Line No.2 and 4 indicates severe noise pollution. The effective boundary of these areas exposed to 70dB (A) noise are within 50m from the track centerline of No.2 line and 25m of No.4 line. The residents file a strong complaints whenever the noise level exceeds the 80dB (A) , and an occasional complaints between 70 to 80 dB(A). The distribution of high level noise of 80 dB(A) occurs within 25m from the track centerline of the overbridge, 12.5m of the short steel bridge, and about loom of the long steel bridge such as Dangsan Bridge. The intermediate noise level of 70 to 80 dB(A) is recorded within 50m from the overbridge, U-type retaining structure, and short steel structure, and 280m from the long steel bridge. The results presented in this paper can be used to understand the characteristics of the noise pollution along the Seoul Subway now In operation, and used as a guide to improve the existing noise pollution problems.

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Fracture Characteristics and Segmentation of Yangsan Fault around Mt. Namsan, Gyeongju City, Korea (경주 남산 일대의 단열구조 특성과 양산단층의 분절)

  • Kim, Heon-Joo;Chang, Tae-Woo
    • The Journal of Engineering Geology
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    • v.19 no.1
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    • pp.51-61
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    • 2009
  • Fractures and segmentation in association with the activities of the Yangsan fault are studied around Mt. Namsan, Gyengju city in the southeastern part of Korea. It is believed that the higher values of joint density and fractal dimension with the approach of the center of the Yangsan fault mean intense fracturing due to the fault activity. The boundary between fault damage zone and host rock is inferred to be placed at about 2.7 km from the center of the Yangsan fault where the values of joint density and fractal dimension abruptly decrease and the orientations of joint are also much dispersed. The small faults within the damage zone of the Yangsan fault are definitely divided into right-lateral and left-lateral strike-slip faults. The former is considered to be formed during the right-lateral movement of the Yangsan fault and the latter during the left-lateral movement. The Yangsan fault is segmented in the study area with obvious evidences as follows: (1) the difference of fault strike between northern and southern segments, (2) The geometry of contractional imbricate fans and syncline plunging $9^{\circ}$, $S85^{\circ}E$ at the end of northern segment, and (3) anticline plunging $28^{\circ}$, $N4^{\circ}W$ at the end of southern segment.

A Field Verification Study on the Effect of Filter Layers on Groundwater Level Drop Characteristics, Permeability, Optimum Yield and Well Efficiency in the Unconfined Aquifer Well for Riverbank Filtration Intake (강변여과수 취수를 위한 충적우물에서 필터층이 수위강하특성, 투수성, 적정양수량 및 우물효율에 미치는 영향에 대한 현장실증 연구)

  • Song, Jae-Yong;Lee, Sang-Moo;Kang, Byeong-Cheon;Lee, Geun-Chun;Jeong, Gyo-Cheol
    • The Journal of Engineering Geology
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    • v.29 no.4
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    • pp.509-529
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    • 2019
  • This study performs to evaluate the role of filter material at alluvial well for intake of riverbank filtration and the applicability and improvement effect of dual filter well. To achieve this objective, dual filter intake well and single filter intake well were installed with different filter conditions at riverbank free surface aquifer in soil layer then we evaluated filter material condition, permeability, optimum yield and well efficiency according to yield in drawdown test. As a results, we assumed forming dual filter layer minimizes sudden speed changes at boundary between aquifer and filter layer by cushioning of groundwater flow. This suppresses warm current then intake groundwater efficiently, therefore it seems decreasing peripheral groundwater level changes in spite of higher intake water amount than single filter intake well. Furthermore, we confirmed by test, installing dual filter improves permeability, optimum yield and well efficiency. The result will be used by combining with former study to set up standard of design/construction of dual filter intake well at alluvial aquifer layer. Furthermore, we expect this result will be used to prove application effect of dual filter intake well compared to single filter one and radial collector well which are mainly applied on riverbank filtration.

Evaluation on the Degree of Satisfaction with Working Environment for Workers Engaged in the Composting Plant with Livestock Manure in the Han-river Watershed (한강유역 축분퇴비공장 근로자의 작업환경 만족도 평가)

  • Kim, K.Y.;Choi, H.L.;Kim, C.N.
    • Journal of Animal Science and Technology
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    • v.44 no.2
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    • pp.261-270
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    • 2002
  • This study was executed to elucidate the degree of satisfaction with working environment and the factors affecting it for workers who are engaged in the composting plants with livestock manure in the Han-river watershed. As an evaluation on site, we applied the self-administered questionaire including general characteristics, working conditions, degree of satisfaction with working environment, and degree of satisfaction with working condition. Simultaneously, we analysed the exposure levels of odor (ammonia, hydrogen sulfide, and odor intensity) in the boundary area of plants. As a result of the study, health condition, odor, work load, dust, and smoking were proved to be the main factors affecting the degree of satisfaction with working environment for workers who are employed in the composting plants with livestock manure in the Han-river watershed. Of them, it was investigated that health condition, odor, and work load accounted for 61.3% of the total degree of satisfaction with working environment and health condition(p$<$0.01), odor(p$<$0.05), work load(p$<$0.05), and dust(p$<$0.05) were statistically significant. It was concluded that the degree of satisfaction with working environment was high for the workers who had good health status and low for the workers who had the relatively considerable work load and were often exposed to odor and dust. Therefore, to increase the degree of satisfaction with working environment for workers who are engaged in the composting plants with livestock manure, the measures that can reduce the exposure levels of odor and dust emitting from the composting plant with livestock manure should be improved.

Health and environmental risk assesment of air pollutants in Gyeongju and its vicinities(I) (경주 주변지역 대기오염물질의 보건.환경 위해성 평가(I))

  • Jung, Jong-Hyeon;Choi, Won-Joon;Leem, Heon-Ho;Park, Tong-So;Shon, Byung-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.12
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    • pp.3740-3747
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    • 2009
  • To protect the citizens' health of Gyeongju and to secure basic data for the assessment of health and environmental risk, distribution characteristics of meteorological elements were investigated and numerical simulation of wind field using RAMS model was carried out. In addition, measurement and analysis of air pollutants, forecasting the behavior air pollutants using ISC-AEROMOD view, and health and environmental risk-influenced zones were defined through managing air polluting materials to prevent health damage and property damage. According to the survey results of air pollution in Gyeongju and surroundings, average annual concentration of air pollutants in Gyeongju was slightly lower than that in Pohang and Ulsan areas, but concentration of particulate matters and nitrogen dioxide at Gyeongju Station Square and Yonggang Crossing were sometimes higher than that in Pohang and Ulsan areas. Results of the modeling of moving and diffusion of air pollutants that affect citizens' health showed that parts of the 1st through 4th industrial complexes together with POSCO were included in particulate matters and sulfur dioxide influenced areas in Pohang Steel Complex area, and that Haedo-dong, Sangdae-dong, Jecheol-dong and Jangheung-dong in Pohangnam-gu represented locally worsened air quality due to a quantity of air pollutant emission from dense steel industries and large scale industrial facilities.

The P300 Source Localization in the Patients with Obsessive-Compulsive Disorder using the LORETA Imaging and SPM (강박장애에서 LORETA 영상을 이용한 P300 국소원의 통계적 분석)

  • Park, Sung-Kun;Choi, Jung-Seok;Yu, Soh-Young;Lee, Bo Reom;Kang, Seung-Suk;Roh, Kyu Sik;Ha, Tae-Hyun;Kwon, Jun Soo
    • Korean Journal of Biological Psychiatry
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    • v.10 no.2
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    • pp.168-176
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    • 2003
  • Objectives:We investigated the characteristics of P300 generators in obsessive-compulsive disorder(OCD) patients by using voxel-based statistical parametric mapping of current density images. Methods:P300 generators, produced by a rare target tone of 1500Hz under a frequent non-target tone of 1,000Hz, were measured in 15 right-handed OCD patients and 15 controls. Low Resolution Electromagnetic Tomography(LORETA), using a realistic head model of the boundary element method based on individual MRI, was applied to the 128-channel EEG. Statistical parametric mapping(SPM) was applied for the statistical analysis. Results:We found that both groups had the mean current density of P300 in the parietal, temporal and prefrontal lobe. There was a trend for decreased current density in the prefrontal area in OCD patients. The statistical comparison showed current density increase in the supraparietal area, a statistically significant longer P300 latency and a trend for reduced P300 amplitude in OCD patients. Conclusion:It suggests that P300 source of both groups exists in multiple brain regions at the same time. And both groups had no statistically significant differences in the current density of P300 except for increased current density in the supraparietal area in OCD patients. But, considering the statistically significant longer P300 latency, a trend for reduced P300 amplitude and relative mean current density reduction in the prefrontal area in OCD patients, this study suggests that the frontal lobe may have a reduced normal inhibitory process in OCD patients.

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