• 제목/요약/키워드: electronic evidence

검색결과 455건 처리시간 0.03초

시간 정보를 활용한 동영상 파일 복원 기법 (Recovery Corrupted Video Files using Time Information)

  • 나기현;심규선;변준석;김은수;이중
    • 한국멀티미디어학회논문지
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    • 제18권12호
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    • pp.1492-1500
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    • 2015
  • In recent crime scene, there is the captured crime scene video at least one. So video files recorded on storage media often provide important evidence. Criminals often attempt to destroy storage saved crime scene video. For this reason recovery of a damaged or deleted video file is important to resolve criminal cases in aspects of digital forensic. In the recent, there is a study to recover video file based on video frames, but it is very poor time efficiency when the connecting video frames. This paper proposed advanced frame-based recovery technique of a damaged video files using time information. We suggest a new connecting algorithm to connect video frames using recorded time information in front of video frame. We also evaluate performance in aspects of time and experiment result shows that proposed method improves performance.

Use of preoperative cone-beam computed tomography to aid in establishment of endodontic working length: A systematic review and meta-analysis

  • Paterson, Andrew;Franco, Vittorio;Patel, Shanon;Foschi, Federico
    • Imaging Science in Dentistry
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    • 제50권3호
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    • pp.183-192
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    • 2020
  • Purpose: This study was performed to assess the accuracy of preoperative cone-beam computed tomography (CBCT), when justified for other reasons, in locating the apical foramen and establishing the working length. Materials and Methods: Six electronic databases were searched for studies on this subject. All studies, of any type, were included if they compared measurements of working length with preoperative CBCT to measurements using an electronic apex locator (EAL) or histological reference standard. Due to the high levels of heterogeneity, an inverse-variance random-effects model was chosen, and weighted mean differences were obtained with 95% confidence intervals and P values. Results: Nine studies were included. Compared to a histological reference standard, CBCT indicated that the apical foramen was on average 0.40 mm coronal of its histological position, with a mean absolute difference of 0.48 mm. Comparisons were also performed to an EAL reference standard, but the conclusions could not be considered robust due to high levels of heterogeneity in the results. Conclusion: A low level of evidence is produced suggesting that preoperative CBCT shows the apical foramen to be on average 0.40 mm coronal to its histological position, with a mean absolute difference of 0.48 mm.

Investigation of the Electronic Structure of Mn12 Molecular Magnet Using Synchrotron Radiation

  • Kang, J.S.;Kim, J. H.;Kim, Yoo-Jin;Jeon, Won-Suk;Jung, Duk-Young;Han, S.W.;Kim, K.H.;Kim, K.J.;Kim, B.S.;Shim, J.H.;Min, B.I.
    • Journal of Magnetics
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    • 제8권4호
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    • pp.149-152
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    • 2003
  • The electronic structure of Mn12-Ac molecular magnet has been investigated using synchrotron radiation. The valence-band photoemission spectroscopy (PES) measurement reveals that Mn 3d states are located near the top of the valence band. The trend in the measured valence-band PES spectra is found to be consistent with that in the calculated local density of states. The Mn 2p x-ray absorption spectroscopy (XAS) measurement provides evidence for the Mn$^{3+}$-Mn$^{4+}$ mixed-valent states.

$Al_2O_3-ZrO_2/A_2O_3$-TZP 세라믹스의 제조 및 기계적.전기적 특성 (Mechanical and Electrical Characteristics of $Al_2O_3-ZrO_2/A_2O_3$-TZP Structural Ceramics)

  • 박재성;남효덕;이희영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 추계학술대회 논문집
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    • pp.335-338
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    • 1999
  • The effect of monoclinic $ZrO_2$(pure) and tetragonal $ZrO_2$ containing 5.35wt% $Y_2$$O_3$(Y-TZP) addition on the mechanical properties and thermal shock resistance of $Al_2$$O_3$ ceramic were investigated. The addition of $ZrO_2$(m) and Y-TZP increased sintering density of $Al_2$$O_3$. The vickers hardness increased with increasing the volume fraction of Y-TZP going through a maximum at 20wt%. The hardness of the specimens was found to be depend on the sintering density. With increasing the volume fraction of $ZrO_2$(m) and Y-TZP, the fracture toughness of the composite is increased. This result may be taken as evidence that toughening of ${Al_2}{O_3}$ can also be achieved by the transformation toughening and microcrack toughening of $ZrO_2$. The property of the& shock for ${Al_2}{O_3}$-$ZrO_2$ composites was improved by increasing the volume fraction of monoclinic $ZrO_2$(pure).Grain size increased with increasing the volume fraction of $ZrO_2$.

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수면단계 뇌파 검출을 위한 Fourier 와 Wavelet해석 (Fourier and Wavelet Analysis for Detection of Sleep Stage EEG)

  • 서희돈;김민수
    • 대한의용생체공학회:의공학회지
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    • 제24권6호
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    • pp.487-494
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    • 2003
  • 수면뇌파의 해석에 있어서 수면단계는 뇌파의 특성파 검출에 특히 중요하다. 수면단계는 여러 수면질환의 진단에 가장 기초적일 단서를 제공한다. 본 연구에서 수면뇌파 신호를 이산 웨이브렛 변환 뿐 만 아니라 퓨우리에 변환, 연속 웨이브렛 변환을 이용해서 해석하였다. 제안된 시스템 방범인 퓨우리에와 웨이브렛은 수면뇌파의 중요한 특성파(유파, 수면방추파, K복합, 구파 REM) 검출을 위해서 수면상태를 분석했다. 수면뇌파 분석에는 Daubechies 웨이브렛 변환 방법과 고속 퓨우리에를 이용했다. 모의실험결과 신경망 시스템이 특성 파형의 분류에 높은 성능을 발휘함을 알 수 있었다.

Gapped Nearly Free-Standing Graphene on an SiC(0001) Substrate Induced by Manganese Atoms

  • Hwang, Jinwoong;Lee, Ji-Eun;Kang, Minhee;Park, Byeong-Gyu;Denlinger, Jonathan;Mo, Sung-Kwan;Hwang, Choongyu
    • Applied Science and Convergence Technology
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    • 제27권5호
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    • pp.90-94
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    • 2018
  • The electron band structure of manganese-adsorbed graphene on an SiC(0001) substrate has been studied using angle-resolved photoemission spectroscopy. Upon introducing manganese atoms, the conduction band of graphene, that is observed in pristine graphene indicating intrinsic electron-doping by the substrate, completely disappears and the valence band maximum is observed at 0.4 eV below Fermi energy. At the same time, the slope of the valence band decreases by the presence of manganese atoms, approaching the electron band structure calculated using the local density approximation method. The former provides experimental evidence of the formation of nearly free-standing graphene on an SiC substrate, concomitant with a metal-to-insulator transition. The latter suggests that its electronic correlations are efficiently screened, suggesting that the dielectric property of the substrate is modified by manganese atoms and indicating that electronic correlations in grpahene can also be tuned by foreign atoms. These results pave the way for promising device application using graphene that is semiconducting and charge neutral.

마미증후군의 한의학적 치료에 대한 연구 분석 (Review of the Studies on the Treatment of Cauda Equina Syndrome Using Korean Medicine)

  • 박종한;정수현
    • 한방재활의학과학회지
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    • 제29권2호
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    • pp.159-169
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    • 2019
  • Objectives The purpose of this study was to assess the use of Korean Medicine for treating cauda equina syndrome. Methods We searched for studies of the use of Korean Medicine for the treatment of cauda equina syndrome in 8 electronic databases and analyzed these studies. Results We found 297 studies on cauda equina syndrome from 8 electronic databases. We excluded 230 duplicate studies, 53 studies that did not involve the use of Korean Medicine and 1 review article. In addition, 13 case studies (13 patients) were included. Acupuncture, herbal medicine (13 times), moxibustion (9 times), pharmacopuncture (8 times), physical therapy (6 times), cupping therapy (5 times), and the bladder stimulation technique (4 times) were used. ST36 for acupuncture, Bojoongikgi-tang as a herbal medicine, CV4 for moxibustion, bee venom as a pharmacopuncture material and BL23 in pharmacopuncture point were the most frequently used. Conclusions Korean Medcine for cauda equina syndrome was effective. However, we found limited evidence regarding Korean Medicine for cauda equina syndrome. Thus, we think various type of studies including much more case reports, for cauda equina syndrome should be performed in the future.

Lip repositioning with or without myotomy: a systematic review

  • Ardakani, Mohammadreza Talebi;Moscowchi, Anahita;Valian, Nasrin Keshavarz;Zakerzadeh, Elham
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제47권1호
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    • pp.3-14
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    • 2021
  • Excessive gingival display is an esthetic issue that is commonly managed by different procedures. Lip repositioning is a modality to address concerns of affected patients. The aim of this review was to investigate the scientific evidence on outcomes and long-term stability of lip repositioning surgery with or without myotomy. The electronic search was conducted in three databases: MEDLINE, Embase, and the Cochrane Library up to October 2019. No publication status, language, or time restrictions were applied. The electronic search was complemented by a manual search of the reference lists. Three hundred thirty-eight studies were screened by title, and 16 articles remained for data extraction. The included studies assessed the lip repositioning procedure in 144 patients aged between 15-59 years (134 females and 10 males). Based on the available data, lip repositioning with myotomy/muscle containment can be a successful treatment for minor discrepancies in gingival display in selected cases. However, further well-organized controlled clinical trials are recommended to derive a conclusion about the long-term stability compared with other alternatives.

Consumption Value, Consumer Innovativeness and New Product Adoption: Empirical Evidence from Vietnam

  • DU, Chung Thi;NGO, Thu Thi;TRAN, Thi Van;NGUYEN, Ngoc Bich Tram
    • The Journal of Asian Finance, Economics and Business
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    • 제8권3호
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    • pp.1275-1286
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    • 2021
  • The purpose of this study is to employ the theory of consumption value and consumers' innovative personality characteristics to explain the adoption of new personal electronics devices in Vietnamese market. This study adapts a quantitative survey-based approach to test hypotheses about relationship between consumption value, product specific innovativeness and new product adoption. The study uses a quantitative data set of 915 consumers who owned one mobile electronic device at least in Ho Chi Minh city, one of the biggest cities of Vietnam. The data was collected through personal interview and convenient sampling method. The conceptual model was tested using PLS structural equation model. The findings of this study suggest that both consumption value and product specific innovativeness influence the adoption of new electronic products. The results also reveal that product specific innovativeness mediates the relationship between consumption value and new product adoption. The study further identified that consumption value was taken as a second-order multidimensions construct with five components, namely functional value, epistemic value, economic value, social value and emotional value. As a result, the research suggests some implications to enhance marketers' capabilities to develop strategies for launching new hi-tech products in an emerging market as Vietnam.

Resistive Switching Properties of N and F co-doped ZnO

  • Kim, Minjae;Kang, Kyung-Mun;Wang, Yue;Chabungbam, Akendra Singh;Kim, Dong-eun;Kim, Hyung Nam;Park, Hyung-Ho
    • 마이크로전자및패키징학회지
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    • 제29권2호
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    • pp.53-58
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    • 2022
  • One of the most promising emerging technologies for the next generation of nonvolatile memory devices based on resistive switching (RS) is the resistive random-access memory mechanism. To date, RS effects have been found in many transition metal oxides. However, no clear evidence has been reported that ZnO-based resistive transition mechanisms could be associated with strong correlation effects. Here, we investigated N, F-co-doped ZnO (NFZO), which shows bipolar RS. Conducting micro spectroscopic studies on exposed surfaces helps tracking the behavioral change in systematic electronic structural changes during low and high resistance condition of the material. The significant difference in electronic conductivity was observed to attribute to the field-induced oxygen vacancy that causes the metal-insulator Mott transition on the surface. In this study, we showed the strong correlation effects that can be explored and incorporated in the field of multifunctional oxide electrons devices.