• Ocean and Polar Research
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• 제42권2호
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• pp.141-155
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• 2020

Species composition of fish in the shallow water at Daecheon beach was determined using monthly beach seine samples collected from April 2010 to March 2011. These data were compared with the previous data, one just after reclamation in 1984-1985, and the other in 1995-96, in order to assess the post-reclamation impact of the environmental change on the fish assemblage. A total of 30 species from 1,464 individuals with biomass of 17,808 g were identified. Dominant species in the number of individuals were Chelon haematocheilus (49.3%), Takifugu niphobles (13.7%) and Paralichthys olivaceus (10.0%). Among pelagic fish, migrant juvenile fish such as Sardinella zunasi and Thryssa kammalensis were abundantly collected in 1984-85, but the catch amount was gradually decreased as time untill only few pelagic fish were collected in 2010-2011. The benthic fish were most abundant in 1984-1985 among habitat groups, and Favonigobius gymnauchen and Kareius bicoloratus were the top two predominants. Species composition of benthic fish did not exhibited drastic changes in 1995-1996, but both the abundance decline and the species composition change was evident in 2010-2011. Among the semi-benthic fish from 1984-1985 samples, Sillago japonica and Konosirus punctatus predominated. Species composition was slightly changed in 1995-1996, but significant changes were met in 2010-2011 with the two predominats, Chelon haematocheilus and Takifufu niphobles. These changes in fish species composition may reflect the post-reclamation effect of the impaired water quality and the accumulation of organic rich fine sediments.

• Computers and Concrete
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• 제16권6호
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• pp.933-961
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• 2015

Damage by high-speed impact fracture is a dominant mode of failure in several applications of concrete structures. Numerical modelling can play a crucial role in understanding and predicting complex fracture processes. The commonly used mesh-based Finite Element Method has difficulties in accurately modelling the high deformation and disintegration associated with fracture, as this often distorts the mesh. Even with careful re-meshing FEM often fails to handle extreme deformations and results in poor accuracy. Moreover, simulating the mechanism of fragmentation requires detachment of elements along their boundaries, and this needs a fine mesh to allow the natural propagation of damage/cracks. Smoothed Particle Hydrodynamics (SPH) is an alternative particle based (mesh-less) Lagrangian method that is particularly suitable for analysing fracture because of its capability to model large deformation and to track free surfaces generated due to fracturing. Here we demonstrate the capabilities of SPH for predicting brittle fracture by studying a slender concrete structure (column) under the impact of a high-speed projectile. To explore the effect of the projectile material behaviour on the fracture process, the projectile is assumed to be either perfectly-elastic or elastoplastic in two separate cases. The transient stress field and the resulting evolution of damage under impact are investigated. The nature of the collision and the constitutive behaviour are found to considerably affect the fracture process for the structure including the crack propagation rates, and the size and motion of the fragments. The progress of fracture is tracked by measuring the average damage level of the structure and the extent of energy dissipation, which depend strongly on the type of collision. The effect of fracture property (failure strain) of the concrete due to its various compositions is found to have a profound effect on the damage and fragmentation pattern of the structure.

• 대한소아치과학회지
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• 제37권2호
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• pp.240-245
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• 2010

제1형 신경섬유종증은 약 3000명당 1명 꼴로 발생되며 상염색체 우성유전질환이다. 피부의 카페오레반점 및 다발성 신경 섬유종과 피부, 신경계, 골격계, 내분비계, 혈관계의 다양한 이형성이 특징이다. 실제적인 구강 내 신경섬유종은 25%의 환자에서 발생한다고 알려져 있다. 제1형 신경섬유종증으로 진단된 만9세의 여아가 치은의 부종을 주소로 본원에 내원하였다. 하악 전치부 설측에 치은비대가 존재하였고, 환자의 사지와 몸통에서 갈색반점인 카페오레 반점을 확인할 수 있었다. 비대된 치은조직을 국소마취 하에 제거하였고, 조직검사를 시행한 결과 신경섬유종으로 확진하였다. 7개월 후 검사 결과 재발의 증거없이 양호한 치유를 보였다. 재발의 가능성이 있으므로 정기적인 검사가 필요하다.

• 감성과학
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• 제17권4호
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• pp.71-78
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• 2014

PET 중공필라멘트 복합 DTY(Draw Textured Yarns)와 ATY(Air-jet Textured Yarns)는 경량의 스포츠 의류를 포함한 고감성 의류용으로 많이 사용되고 있다. 본 연구는 중공섬유 복합 DTY와 ATY 복합사 직물의 수분 및 열이동에 관계되는 쾌적특성에 중공 복합사 및 직물의 구조 특성이 어떠한 영향을 미치는 가에 대한 분석이다. 기공의 크기가 큰 중공 복합 직물의 흡수성이 우수하였고 커버팩터는 영향을 미치지 않았다. 또한 ATY사 직물이 DTY사 직물에 비해 흡수성이 우수하였다. 반면, 건조특성은 기공 사이즈가 미세한 직물이 기공사이즈가 큰 직물보다 건조시간이 짧았으며 낮은 커버팩터와 기공 사이즈가 작은 하이멀티사 직물이 중공 복합직물에 비해 건조 특성이 우수하였다. 직물의 기공 사이즈는 공기투과도와 열전도도 특성에 가장 중요한 인자였다. 직물의 큰 기공도는 중공 복합 직물의 기공도와 열전도도에 비선형적인 반비례 상관관계를 나타냈다.

• 한국지구과학회지
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• 제24권6호
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• pp.568-577
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• 2003

본 연구는 우리나라의 서해안에서 해안사구의 발달이 탁월한 충청남도 태안군의 학암포, 천리포, 만리포, 몽대포, 몽산포, 삼봉, 서천군의 송림리를 선정하여 해빈과 해안사구를 구성하는 물질의 특성과 공급원, 고사구와의 관계를 밝히는 것을 목적으로 한다. 충청남도 해안은 태안반도와 안면도를 비롯하여 육지가 바다로 돌출한 지역을 중심으로 해안선의 출입이 심한 것이 특징이다. 특히 헤드랜드에 의해 분리된 만입으로는 파랑의 작용이 비교적 활발하게 미치므로 해빈이 발달한다. 해빈의 모래는 서풍 계열의 바람에 불려 해안사구를 이루고 있다. 본 연구 지역에서는 연중 남서풍 계열의 바람이 지속적으로 불어온다. 본 연구 지역에 분포하는 해빈과 해안사구는 거의 대부분 석영과 장석으로 이루어졌으며 운모, 중광물도 포함한다. 학암포 해수욕장의 경우 석영 72.6%, 장석 20.3%, 운모 3.3%이고 이 밖에 각섬석, 녹렴석, 전기석, 지르콘, 기타 철산화물이 소량 포함되었다. 충청남도 해안은 모래가 부족한 편이며 화강암 기원의 것을 제외하면 입도가 아주 작고 원마도가 불량한 것이 특징이다. 이는 모래의 이동 거리가 길지 않았음을 의미한다. 모래부족은 해빈의 침식과 해안선의 후퇴로 나타난다. 본 연구 지역의 해안사구는 플라이스토세의 고사구충을 기반으로 발달하였다.

• 한국해양학회지
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• 제27권1호
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• pp.66-77
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• 1992

태안반도 외해역에서 고해상용 천부지층 기록지상에 나타나는 조류성사퇴들 및 sand waves 발달 특징과 표층 퇴적물의 특성 결과를 조류 분포와 관련하여 사질 퇴적 물의 이동양상을 추정하였다. 조사해역에는 비대칭형 사퇴들이 북동-남서방향이 우세 한 강한 조류방향과 평행하거나 반시계방향으로 약간 빗겨지면서 길게 발달하고 있으 며 대부분의 사퇴들은 남 내지 남동쪽으로 급사면을 가지며 대략 남쪽방향으로 사층리 구조가 발달하고 있는 특징을 가진다. 현세 퇴적층은 사퇴들의 퇴적층 두께와 발달 양 상을 보여주며 분포한다. 이 결과로부터 현세 활동성사퇴들은 남동, 남 그리고 남서쪽 방향의 외해를 향해 퇴적물을 전적으로 이동시키는 것으로 해석된다. 동쪽 내지 북동 쪽의 급사면을 갖는 비대칭형 sand waves 가 수심 약 40-60 m를 보이는 일부 지역의 평탄한 해저면에 발달 분포한다. Sand waves 가 발달한 지역의 표층 퇴적물은 세립사 질 퇴적물로서 분급도가 매우 양호하게 나타나며 이들 지역의 사질 퇴적물은 동쪽 내 지 북동쪽 육지를 향해 이동되는 것으로 사료된다.

• Asian Journal of Atmospheric Environment
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• 제12권3호
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• pp.274-288
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• 2018

Quantitative data of 50 non-polar organic compounds constituting $PM_{2.5}$ were continuously collected and analyzed from June 2016 to October 2017 (approximately 17 months) at Ichihara, one of the largest industrial areas in Japan. Target non-polar organic compounds including 21 species of polycyclic aromatic hydrocarbons (PAHs), 24 species of n-alkanes and 5 species of phthalate esters(PAEs) were simultaneously measured by gas chromatography/mass spectrometry. Basically, the average concentrations of the total PAHs, n-alkanes and PAEs in each season remained nearly level, and seasonal variations were little throughout the study period. These results suggest that the emission sources, which are not influenced by the seasons, are the dominant inputs for the target organic compounds. Diagnostic ratios of PAHs, assessment of n-alkane homologue distributions, carbon preference index, and the contribution of wax n-alkanes from plants were used to estimate source apportionments. These results indicate that anthropogenic sources were the main contributor for most PAHs and n-alkanes throughout the study period. The concentrations of PAEs selected in this study were low because emission amounts of these chemicals were little within the source areas of the sampling site. To our knowledge, this study is the first attempt to simultaneously measure a high number of non-polar organic compounds in $PM_{2.5}$ collected from the ambient air of Japan, and the resultant data will provide valuable data and information for environmental researchers.

• 한국실내디자인학회논문집
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• 제19권5호
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• pp.140-147
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• 2010

The objectives of this study are, first to define the concept of restaurant total coordination and establish its components as a design strategy for planning and managing all elements comprising a restaurant, and second, to survey the total coordination of Japanese restaurants in foreign countries and examine how traditionality, which is an element for globalizing Japanese restaurants, is expressed. This study was conducted through literature review for defining the concept of restaurant total coordination and extracting its components and a field survey for analyzing the current state of restaurant total coordination and traditionality expression methods. The results of this study are as follows. First, Japanese restaurants categorized into Type A with relatively high traditionality expression(3.3 or higher) were 25% of the surveyed restaurants. These restaurants showed the traditional characteristics of Japanese style as they are without contemporary adaptation for all components of restaurant. Second, 41.7% of the restaurants were categorized into Type B with traditionality expression between 1.7 and 3.3. They were mostly popular casual restaurants at which people can enjoy Japanese food comfortably. In visual and spatial design elements, traditional and contemporary styles appeared in the equal percentage, and decoration, table setting and food design were styled according to Japanese traditions. Third, 4 cases(33.3%) were categorized into Type C with traditionality expression below 1.7. Because they were fine dining restaurants that sold high priced dishes, formality and consistency were also high. Through all design elements including visual, spatial, table setting and food design elements, elegant and simple contemporary images were dominant. The results of this study will be used as basic materials to establish the concept of total coordination that views the visual, spatial, table setting and food design elements comprising a restaurant, which were approached separately in previous studies on restaurants, together from the viewpoint of integrative deigns, and to make design strategies for globalizing Korean restaurants based on Japanese restaurant cases.

• Journal of Korean Society for Atmospheric Environment
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• 제21권E1호
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• pp.23-35
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• 2005

Size distribution of particulate water-soluble ion components was measured at Gosan, Korea using a micro-orifice uniform deposit impactor (MOUDI). Sulfate, ammonium, and nitrate showed peaks in three size ranges; Sulfate and ammonium were of dominant species measured in the fine mode ($D_{p} < 1.8 {\mu}m$). One peak was observed in the condensation mode ($0.218\sim0.532{\mu}m$), and the other peak was obtained in the droplet mode ($0.532\sim1.8{\mu}m$). Considering the fact that the equivalent ratios of ammonium to sulfate ranged from 0.5 to 1.0 in these size ranges, it is inferred that they formed sufficiently neutralized compounds such as ($NH_{4})_{2}SO_{4} and (NH_{4})_{3}H(SO_{4})_{2}$ during the long-range transport of anthropogenic pollutants. On the other hand, nitrate was distributed mainly in the coarse mode ($3.1\sim6.2{\mu}m$) combined with soil and sea salt. Two sets of MOUDI samples were collected in each season. One sample was collected when the concentrations of criteria air pollutants were relatively high, but the other represented relatively clean air quality. The concentrations of sulfate and ammonium particles in droplet mode were the highest in winter and the lowest in summer. When the air quality was bad, the increase of nitrate was observed in the condensation mode ($0.218\sim0.282{\mu}m$). It thus suggests that the nitrate particles were produced through gas phase reaction of nitric acid with ammonia. Chloride depletion was remarkably high in summer due to the high temperature and relative humidity.

• Journal of Plant Biology
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• 제17권4호
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• pp.158-162
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• 1974

Some ecological attributes of perennial plants and Pb contamination were analyzed for study plots near an entrance of Nevade Test Site at Mercury Valley, Nye County, Nevada. The surface of the desert pavement soil was composed of stones (1 to 4cm diameter). The underside of each stone was coated with coarse and fine sand (about 90%). The profiles of soil were constituted with the A-horizon and C-horizon only. The soil pH at the plots ranges from 7.6 to 8.5, C/N was 13 and cation exchange capacity showed 15me/100g. Nine species and 42 number of individuals were found in all plots. Franseria dumosa and Larrea divaricata were dominant species. The discrete clumps of vegetation were consisted of 9 species of common perennials and these were covered about 25% on desert pavement, on the other words, bare area without vegetation was about 75%. The size and spacing of the plants was irregular. Community coefficient as comparison between shrub species in these study area and those in near the low elevation desert indicated a low degree of similarity. Density, cover and productivity in the study plots as compared with those in the nearest study areas in Mercury Valley showed a higher value. The soils in the studied area involved high heavy metal contents in the plant tissue was higher than those of its soil. The leavds of Lycium andersonii tended to accumulate more Zn and Mo than those of the other species. Larrea divaricata leaves accumulated very high leaves of Fe and Ephedra nevadensis were generally high in Mn. Lead contamination was apparent in foliage of desert vegetation collected alongside the roadway, reflecting the variation in traffic volume. Lead contents greater than fifteen-fold of normal (low traffic) were found in plant foliage alongside the heavily traveled roadway. Lead content of old foliage by the heavily traveled roadway was as much as 129 ppm but that of new foliage 17 ppm only.