• Title/Summary/Keyword: Fingerprints

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A Study on How to Improve Empty Print to Cyanoacrylate Fuming Developed by Vacuum Metal Deposition (Vacuum Metal Deposition으로 현출된 Empty Print를 Cyanoacrylate Fuming로 개선하는 방법에 관한 연구)

  • Lee, Wonyoung;Kim, Youjin;Lee, Munhee;Yu, Jeseol
    • The Journal of the Korea Contents Association
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    • v.21 no.12
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    • pp.331-336
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    • 2021
  • Vacuum metal deposition(VMD) using gold and zinc is known as a very sensitive technique of developing latent fingerprints on nonporous surfaces by excellent malleability and ductility of gold. However, VMD produces empty print which cannot be identified. There is only presumption about the cause of occurrence of empty print, the exact cause is not known. In this study, we experiment on the freshness of fingerprints and sensitivity of techniques that are estimated as the factors causing empty print, based on this, we suggest cyanoacrylate fuming is effective to redevelop empty print.

Robust Audio Fingerprinting Using Compressed-Domain Features (압축 도메인 특징을 이용한 강인한 오디오 핑거프린팅)

  • Seo, Jin-Soo;Lee, Seung-Jae
    • The Journal of the Acoustical Society of Korea
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    • v.28 no.4
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    • pp.375-382
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    • 2009
  • This paper proposes a new audio fingerprinting method based on compressed-domain features. By basing on the compressed domain, the computational efficiency of the proposed method can be greatly enhanced. Especially we deal with MDCT domain, which is widely employed in audio compression, and extract three kinds of subband features; energy, centroid, and flatness. By taking signs after differentially filtering each feature, binary audio fingerprints are obtained. The identification performance of the three kinds of fingerprints are experimentally compared. Among the considered compressed-domain subband features, the subband energy showed the best performance for fingerprinting.

A Preliminary Study on the Source Fingerprints of Volatile Organic Compounds (휘발성유기화합물의 배출원 구성물질 성분비에 관한 기초 연구)

  • 이영재;이학성;강병욱;신대윤
    • Journal of Environmental Science International
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    • v.12 no.4
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    • pp.487-496
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    • 2003
  • The purpose of this study was to develop the preliminary source fingerprints of volatile organic compounds (VOC). The source categories studied were vehicles, gasoline vapor, gasoline storage tank, coating, dry cleaning and road covering. The source samples were collected using 6L electro-polished stainless steel canisters for about 20 seconds. From this study, the main component emitted from VOC sources in Korea was toluene. The toluene proportion for road covering, vehicles, coating and gasoline vapor were 35, 18, 16 and 5%, respec- tively. The C$_2$-C$\sub$5/ alkane and alkene compounds were mainly emitted from vehicles, gasoline vapor and gasoline storage tank. The main compounds of coating were m/p-xylene(34%), toluene(16%), 1,2,4-TMB(10%) and o-xylene(9%), which are aromatic hydrocarbons. In the case of dry cleaning, nonane(41%), 1,2,4-TMB (22%) and 1,3,5-TMB(13%) were mainly emitted.

Enhancement of cyanoacrylate-developed marks using p-dimethylaminobenzaldehyde (DMAB) on semi-porous surfaces and analysis of the influence factors on fluorescence intensity (반다공성 재질에 유류된 지문의 CA 훈증 후 p-dimethylaminobenzealdehyde(DMAB) 형광시약 적용 시 표면적과 주변 온도, 기압이 형광착색에 미치는 효과에 관한 연구)

  • Yu, Je-Sul;Kim, Ju-Hah
    • Analytical Science and Technology
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    • v.27 no.4
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    • pp.187-195
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    • 2014
  • It is very important to minimize the damage of latent fingerprints at enhancing the contrast. This study proves the enhancement effects of cyanoacrylate-fumed latent fingerprints using p-dimethylaminobenzealdehyde (DMAB) on semi-porous surfaces and the influence factors. The latent fingerprints in experiment were developed for cyanoacrylate treatment in a vacuum chamber and used after drying at room temperature for 24 hours. For fluorescence staining, the cyanoacrylate-developed marks using DMAB were sublimated during 48 hours under the different conditions of surface area, temperature, atmospheric pressure. First experiment showed how surface area effects on the sublimation rate and fluorescence intensity by DMAB of particle size and container size. In addition, the fluorescence staining using DMAB with solvent-free contact method had the greatest fluorescence intensity after 36 hours and a low fluorescence intensity over a certain size of surface area. Second experiment showed that the evaporation of DMAB solid crystals got a satisfying result in a temperature of $20^{\circ}C$ and reduced time to get the greatest fluorescence intensity. It took a long time to get a optimum level of fluorescence intensity at $30^{\circ}C$ or more and it was less effective in fluorescence intensity. Third experiment on the pressure indicated that the fluorescence intensity of vacuum was weaker than nonvacuum but it was inapplicable to very high variations in pressure.

Developing of latent fingerprint on human skin (생체피부에서의 잠재지문 현출)

  • Lee, Hee-Il;Choi, Mi-Jung;Kim, Jai-Hoon;Park, Sung-Woo
    • Analytical Science and Technology
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    • v.21 no.3
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    • pp.222-228
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    • 2008
  • On living skin the chances of a successfully developing latent fingerprint are very limited. This is due to the fact that continual perspiration and rapid absorption diffuse into the lipophillic layer on skin. A study was conducted to investigate effectively developing method of latent fingerprints on human skin surfaces and pig skin likely corpse's skin. We used commercial fingerprint powder, black powders, black magnetic powder, fluorescence magnetic powder, Cyanoacrylate fuming (CA) and direct lifting methods (lifting paper, glasses and photo glossy paper). Developing of fresh fingerprints on living skin was achieved with S-powderblack, CA fuming and CA fuming following S-powder, fluorescence powder. The other powder tends to overwhelm the latent print and the background. But, latent fingerprint residue was disappeared with time after deposit on a living surface. In case of pig skin likely corpse's skin, latent fingerprint detection was achieved with CA fuming following S-powder and deposited print during 6 hr at $25^{\circ}C$, 40% relative moisture yielded excellent fingerprints with clear ridge details using 1 min CA fuming. And enhancement of fingerprint detection image using forensic light source was achieved.

Fingerprint Minutia Matching Using Adaptive Distance (적응적 거리를 이용한 지문 정합 방법)

  • 이동재;김선주;이상준;김재희
    • Proceedings of the IEEK Conference
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    • 2000.11d
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    • pp.263-266
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    • 2000
  • We proposes a new fingerprint minutia matching algorithm which matches the fingerprint minutiae by using adaptive distance. In general, fingerprint is deformed by pressure and orientation when a user press his fingerprint to sensor. These nonlinear deformations change the distance between minutiae and reduce verification rate. We define the adaptive distance using ridge frequency. Adaptive distance normalizes the distance between minutiae and compensates for nonlinear deformation. Our algorithm can distinguish two different fingerprints better and is more robust. Experimental results show that the performance of the proposed algorithm is superior to using Euclidean distance.

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Comparison of Contour-Tracing Based Thinning Algorithms (윤곽선 추적 기반의 세선화 알고리듬 비교)

  • 김기수;이정환;심재창
    • Proceedings of the IEEK Conference
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    • 1999.11a
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    • pp.1101-1104
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    • 1999
  • This paper performed a comparative study on contour tracing based thinning algorithms. These algorithms are widely used for extracting skeleton due to its superiority to other techniques in processing speed to perform comparison. We selected general eight images consisted of fingerprints, characters, and figures. According to experimental results, we compared each algorithm in performance and ability made skeleton.

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PAH Source Fingerprints for Municipal Incinerator and Motor Vehicle Fuels and Industrial Boilers Emission (발생원별에 따른 PAHs 배출특성)

  • 박찬구;윤중섭;김민영;김명희
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.11a
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    • pp.165-166
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    • 2003
  • 국내에서의 PAHs 연구결과 들은 아직도 측정·분석방법의 평가 등에 관한 수준에 머무르고 있으며, 전국적인 PAHs의 배출원 조사와 배출량 추정 등 체계적인 배출상태조사(emission inventory)와 배출특성 등에 관한 조사·연구 사례는 전무한 실정이다. 더욱이 오래 전부터 이 분야에 많은 관심을 가진 나라에서도 이 분야에 대한 연구가 입자상 물질에 흡착되어 있는 PAHs에 국한되고 있는 실정이다. (중략)

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