• 제목/요약/키워드: dark surfaces

검색결과 45건 처리시간 0.021초

Acidic hydrogen peroxide를 이용한 어둡거나 다양한 색상의 표면에 부착된 혈흔의 증강 (Enhancement of bloodstain on the dark or multi-colored surfaces by using the acidic hydrogen peroxide)

  • 홍성욱;이원영;변재영;신현주;하재욱
    • 분석과학
    • /
    • 제36권3호
    • /
    • pp.121-127
    • /
    • 2023
  • 범죄 현장에서 혈액을 찾아 식별하는 것은 신원 확인 및 사건 재구성을 하기 위해 중요한 과정이다. 하지만, 혈액은 어둡거나 다양한 색상의 표면에서 육안으로 관찰하기 어려울 수 있다. Acidic hydrogen peroxide (AHP)는 최근에 발표된 혈액 증강 시약으로, 카메라의 장노출 기능을 사용하면 혈액을 높은 감도로 관찰할 수 있다. 그러나 어둡거나 다양한 색상의 표면에서 기존에 알려진 기법과 비교된 바는 없다. 이를 위해, 어둡거나 다양한 색상의 표면 8 종류에 혈흔족적을 남기고 UV나 IR을 비추면서 관찰/촬영하는 방법, alginate 전사법, leuco rhodamine 6G (LR6G), AHP를 적용하여 비교하였다. 그 결과, AHP는 UV 및 IR 촬영법보다 증강한 혈액과 표면의 contrast가 높았고, alginate 전사법과 달리 모든 표면에서 적용이 가능했다. 또한 LR6G와 마찬가지로 AHP 역시 어둡거나 다양한 색상의 표면에 부착된 혈액을 성공적으로 증강하였다.

Effect of Muscle pH and Display Conditions on Surface Color in Hanwoo (Korean Native Cattle) Beef

  • Lee, S.K.;Kim, Y.S.;Kim, J.Y.;Song, Y.H.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제14권3호
    • /
    • pp.365-371
    • /
    • 2001
  • The effects of light exposure and light intensity on surface color of Hanwoo (Korean native cattle) beef and color stability of fresh normal and DFD (dark, firm, dry) muscles during 7 days at $4{\pm}1^{\circ}C$ under three display conditions (Dark, Light1000 and Light3000) were investigated. The $L^*$, $a^*$, $b^*$, $C^*$ values and R630-R580 were significantly (p<0.05) higher in normal beef than in DFD beef. The $a^*$, $b^*$, $c^*$ values and R630-R580 of normal beef increased during the first day of display except Light3000 group, then gradually decreased over time. The surfaces of Hanwoo beef accumulated more metmyoglobin in the light than in the dark. Also, the rate of decrease in redness during refrigerated storage was enhanced by light exposure and increase in light intensity. Discolorations were more rapid in DFD beef than normal beef. Increasing light intensity promoted not only discoloration but also lipid oxidation. Therefore storage in the dark is effective in retarding the formation of a brown color in Hanwoo beef.

도시녹지에 의한 미기후개선의 기능 (Function of Microclimate Amelioration by Urban Greenspace)

  • 조현길;안태원
    • 한국조경학회지
    • /
    • 제27권4호
    • /
    • pp.23-28
    • /
    • 1999
  • This study measured transpiration rate of urban trees and albedos of urban surfaces, and examined the function of microclimate amelioration by urban greenspace. Transpiration rates of trees were highest in July and August of growing months. Transpiration per unit leaf area for the two months was 300-350 g/$m^2$/h for Platanus occidentalis, 210-270 g/$m^2$/h for Ginkgo biloba and Zelkova serrata, and 130-140 g/$m^2$/h for Acer palmatum. Surface albedos were 0.09 for asphalt paving and 0.68 for white wall, which reveals that light-colored surfaces are better than dark-colored ones to lower the heat build-up. Due to lack of evapotranspiration, concrete surfaces were, at t midafternoon maximum, 8$^{\circ}C$ hotter than grass ones, though the albedo of concrete paving was higher thant that of grass and trees. Summer air temperatures at places with 12% and 22% cover of woody plants were, respectively, 0.6$^{\circ}C$ and 1.4$^{\circ}C$ cooler than a place with no vegetation. To mitigate the impacts of urban heat islands, required are minimization of hard surfaces, light-coloring for building surfaces, and greenspace enlargement including more plantings.

  • PDF

법광원을 이용한 복잡한 배경의 잠재지문 시각화 및 증강에 관한 연구 (A study on Visualization and Enhancement the Latent Fingerprints on Multi-colored Surfaces using the Forensic Light Sources)

  • 조형우;고현서;한상균;유제설
    • 한국콘텐츠학회논문지
    • /
    • 제16권3호
    • /
    • pp.72-80
    • /
    • 2016
  • 범죄 현장에서 발견되는 증거물에서 지문을 현출하는 다양한 방법이 있다. 다양한 기법 중에 증거물의 상태와 조건에 따라 가장 적합한 것을 적용해야 한다. 본 연구에서는 여러 색상으로 이루어진 복잡한 배경의 표면에 유류된 지문을 현출할 수 있는 법광원 이용 기법 세 가지를 비교하여 보았다. 색상, 표면의 모양, 표면의 질감에 따라 다양한 검체를 선정하였으며 형광 분말, 적외선 사진 촬영, 에피스코픽 동축 조명을 이용하여 잠재지문을 현출하였다. 형광 분말은 모든 표면에서 지문과 배경의 대조비가 커서 좋은 결과를 보였고 IR사진 촬영은 지문과 배경의 대조가 뚜렷하게 관찰되었으나 검정색이 포함된 배경에서는 대조비가 떨어졌다. 에피스코픽 동축 조명 촬영은 광택이 있는 평면 표면에서만 좋은 결과를 나타냈다. 전반적으로 형광 분말이 표면의 특성에 관계없이 지문 현출 효과가 우수하였으나 특정 표면에서는 IR사진 촬영이 더 뛰어나다는 것을 확인하였다.

Impacts of Different Urban Surfaces on Summer Thermal Performance

  • Jo, Hyun-Kil;Wu, Qian
    • 한국환경과학회지
    • /
    • 제24권6호
    • /
    • pp.819-826
    • /
    • 2015
  • This study measured temperatures and albedos of urban surfaces for different colors and materials during summer, and calculated the energy budget over different urban surfaces to find out the thermal performance affecting the heat built-up. The study selected six surface colors and 13 materials common in urban landscape. Their surface temperatures (Ts) and albedos were measured at a given time interval in the daytime from June to August. Average Ts over summer season for asphalt-colored brick was $4.0^{\circ}C$ higher than that for light red-colored one and $9.7^{\circ}C$ higher than that for white-colored one. The Ts for artificial surface materials of asphalt paving, brown brick wall, and green concrete wall was $6.0^{\circ}C$ higher than that for natural and semi-natural ones of grass, grassy block, and planted concrete wall. There was the greatest difference of $16.3^{\circ}C$ at midafternoon in the Ts between asphalt paving and planted concrete wall. Average albedo over summer season of surface materials ranged from 0.08 for asphalt paving to 0.67 for white concrete wall. This difference in the albedo was associated with a maximum of $15.7^{\circ}C$ difference at midafternoon in the Ts. Increasing the albedo by 0.1 (from 0.22 to 0.32) reduced the Ts by about $1.3^{\circ}C$. Average storage heat at midday by natural and semi-natural surfaces of grass and grassy block was about 10% lower than that by artificial ones of asphalt, light-red brick, and concrete. Reflected radiation, which ultimately contributes to heating the urban atmosphere, was 3.7 times greater for light-red brick and concrete surfaces than for asphalt surface. Thus, surfaces with in-between tone and color are more effective than dark- or white-colored ones, and natural or semi-natural surfaces are much greater than artificial ones in improving the urban thermal environment. This study provides new information on correlation between Ts and air temperature, relationship between albedo and Ts, and the energy budget.

Photoluminescence of Porous Silicon Carbide in Solvents

  • Lee, Ki-Hwan;Lee, Tae-Ho;Yoon, Seok-Won;Lee, Seung-Koo;Jeon, Hae-Kwon;Choi, Chang-Shik
    • Journal of Photoscience
    • /
    • 제12권3호
    • /
    • pp.171-174
    • /
    • 2005
  • The relationship between porous surfaces and photoluminescence (PL) behavior of porous silicon carbide (PSC) in various solvents has been studied. The porous surfaces of p-type silicon carbide can be fabricated by electrochemical anodization from the 6H, 15R, 4H-${\alpha}$-SiC substrates in dark-current mode (DCM) condition. We have been investigated the dependence of the PL spectra of PSC under the medium having the different dielectric constants. It has been found that PL depends sensitively on the environment surrounding the surface. The extent of chemically stability on the surface of PSC due to the various solvents was confirmed by reflectance Fourier transform infrared (FTIR) spectroscopy. Detailed IR experiments on the PSC samples were carried out before and after various solvents immersion. These results will be offered important information on the origin of PL in porous structure.

  • PDF

초등학교(初等學校) 교실(敎室)의 시환경(視環境)에 관한 조사연구(調査硏究) (A Survey on the Visual Environment in the Classrooms of Elementary Schools)

  • 정진현
    • 교육시설
    • /
    • 제3권1호
    • /
    • pp.53-58
    • /
    • 1996
  • The purpose of this study was to obtain a new guideline on designing the visual environment in the classrooms of elementary schools. This study was carried out through the field measurements on the classrooms and a survey using the questionnaire about the visual environment for learning. The major findings of the study were as follows: (1) It was unbalanced among the illumination, luminance, and color distributions in the classrooms. (2) It was too bright or dark around the surrounding surfaces (walls, floors, and ceilings) of students in the classrooms. Therefore, it is needed to be careful attention on the light distribution and the reflection ratio around the surrounding surfaces of students in the classrooms.

  • PDF

회전 원판 위 액막 유동 찢김 가시화 (Visualization of rupturing of rotating films)

  • 김동주;김대겸
    • 한국가시화정보학회지
    • /
    • 제22권1호
    • /
    • pp.28-33
    • /
    • 2024
  • We visualized the rupturing of liquid films flowing over a disk rotating with large angular velocity. A setup of high speed imaging for liquid flows on dark and reflective surfaces are suggested. From the result, rivulet structures are revealed to be strongly governed by three-dimensional surface structures developed in the film flow. Additionally, unique flow structures including the rivulet sliding and internal meandering are investigated. Generation mechanism of such structures are discussed in terms of the dynamic contact angle theory.

배경에 따른 혈문증강 시약(Fuchsin Acid, Eosin-Y, Acid Yellow 7) 적용의 현출도 비교실험 (Development Comparative Experiments of Blood Prints Enhancement Reagent (Fuchsin Acid, Eosin-Y, Acid Yellow 7))

  • 김아람;김우중;정혜영
    • 한국콘텐츠학회논문지
    • /
    • 제13권6호
    • /
    • pp.194-201
    • /
    • 2013
  • 강력사건에서 혈액지문은 범인과 피해자를 연결하는 중요한 증거물이기에 현재까지도 이에 대한 많은 실험과 연구가 이루어지고 있다. 과거부터 Fuchsin Acid와 Acid Yellow7간의 비교는 이루어져왔으나, Eosin-Y의 경우 국내에 조직염색시약으로만 알려졌을 뿐 직접적으로 지문에 적용된 사례가 없다. Fuchsin Acid는 특유의 붉은색으로 인해 밝은 배경에서 좋은 대조비를 보이지만, 어두운 배경에서는 Gel lifter를 적용해야 형광이 관찰되는 등 번거로움이 있다. 또한 Gel lifter 사용 시 지문의 좌우가 바뀌기 때문에 주의를 기울여야 한다. Acid Yellow 7은 노란색의 결과물이 현출되기 때문에 밝은 배경에서는 대조비가 좋지 않지만, 어두운 배경에서 매우 강한 형광을 나타냈다. Eosin-Y의 경우 분홍색의 결과물로 인해 밝은 배경에서 Acid Yellow 7에 비해 대조비가 좋았으며, 어두운 배경에서는 Fuchsin Acid 보다나은 형광이 관찰되었다. 물론 Eosin-Y가 밝은 배경에서의 Fuchsin Acid 및 어두운 배경에서의 Acid Yellow 7 형광에 비해서 효과성은 다소 떨어지나 배경에 구애받지 않는다는 장점이 있기에 현장에서 근무하는 수사요원에게는 보다 효과적인 혈액지문증강이 될 것이다.

CELLULAR ATTACHMENT AND GENE EXPRESSION OF OSTEOBLAST-LIKE CELLS ON ZIRCONIA CERAMIC SURFACES

  • Pae, Ah-Ran;Lee, Hee-Su;Kim, Hyeong-Seob; Baik, Jin;Woo, Yi-Hyung
    • 대한치과보철학회지
    • /
    • 제46권3호
    • /
    • pp.227-237
    • /
    • 2008
  • STATEMENT OF PROBLEM: Zirconium oxide can be a substitute to titanium as implant materials to solve the esthetic problems of dark color in the gingival portion of implant restorations. PURPOSE: This study was performed to define attachment and growth behavior of osteoblast- like cells cultured on grooved surfaces of zirconium oxide and evaluate the genetic effect of zirconium oxide surfaces using the reverse transcriptase-polymerase chain reaction (RT-PCR). MATERIAL AND METHODS: MC3T3-E1 cells were cultured on (1) commercially pure titanium discs with smooth surface (T group), (2) yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) with machined surface (ZS group), and (3) Y-TZP with $100{\mu}m$ grooves (ZG group). Cell proliferation activity was evaluated through MTT assay and cell morphology was examined by SEM. The mRNA expression of Runx2, alkaline phosphatase, osteocalcin, TGF-${\beta}1$, IGF-1, G3PDH in E1 cells were evaluated by RT-PCR. RESULTS: From the MTT assay, after 48 hours of adhesion of MC3T3-E1 cells, the mean optical density value of T group and ZG group significantly increased compared to the ZS group. SEM images of osteoblast-like cells showed that significantly more cells were observed to attach to the grooves and appeared to follow the direction of the grooves. After 24 hours of cell adhesion, more spreading and flattening of cells with active filopodia formation occurred. Results of RT-PCR suggest that T group, ZS group, and ZG group showed comparable osteoblast-specific gene expression after 24 hours of cell incubation. CONCLUSION: Surface topography and material of implants can play an important role in expression of osteoblast phenotype markers. Zirconia ceramic showed comparable biological responses of osteoblast-like cells with titanium during a short-time cell culture period. Also, grooves influence cell spreading and guide the cells to be aligned within surface grooves.