• 제목/요약/키워드: Packed technique

검색결과 79건 처리시간 0.019초

좀비 클라이언트 차단을 위한 실행 압축 기술에 관한 연구 (A Study on Generic Unpacking to Prevent Zombie Client on Mobile Platform)

  • 고종빈;이상하;손태식
    • 한국항행학회논문지
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    • 제17권5호
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    • pp.545-551
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    • 2013
  • 다양한 악성코드 탐지 및 분석 회피 기술 중 실행 압축 기술은 악성코드의 용량을 줄이고 분석가가 코드를 분석할 때 혼란을 주도록 코드가 변형되기 때문에 악성코드의 확산이 용이해지고 분석하는데 시간이 오래 걸려 신속한 대응이 어렵게 만들고 있다. 본 논문에서는 실행 압축 도구들을 분석하고 엔트로피 값의 변화량을 기반으로 하는 실행 압축 기술 무력화 방법을 제안한다.

랭뮤어-블롯젯을 통해 형성된 고밀도 양자점 박막과 이를 기반으로 한 발광다이오드 (Light-emitting Diodes based on a Densely Packed QD Film Deposited by the Langmuir-Blodgett Technique)

  • 이승현;정병국;노정균
    • 센서학회지
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    • 제31권4호
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    • pp.249-254
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    • 2022
  • To achieve high-performance colloidal quantum dot light-emitting diodes (QD-LEDs), the use of a densely packed QD film is crucial to prevent the formation of leakage current pathways and increase in interface resistance. Spin coating is the most common method to deposit QDs; however, this method often produces pinholes that can act as short-circuit paths within devices. Since state-of-the-art QD-LEDs typically employ mono- or bi-layer QDs as an emissive layer because of their low conductivities, the use of a densely packed and pinhole-free QD film is essential. Herein, we introduce the Langmuir-Blodgett (LB) technique as a deposition method for the fabricate densely packed QD films in QD-LEDs. The LB technique successfully transfers a highly dense monolayer of QDs onto the substrate, and multilayer deposition is performed by repeating the transfer process. To validate the comparability of the LB technique with the standard QD-LED fabrication process, we fabricate and compare the performance of LB-based QD-LEDs to that of the spin-coating-based device. Owing to the non-destructiveness of the LB technique, the electroluminescence efficiency of the LB-based QD-LEDs is similar to that of the standard spin coating-based device. Thus, the LB technique is promising for use in optoelectronic applications.

코드은닉을 이용한 역공학 방지 악성코드 분석방법 연구 (A New Analysis Method for Packed Malicious Codes)

  • 이경률;임강빈
    • 한국항행학회논문지
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    • 제16권3호
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    • pp.488-494
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    • 2012
  • 본 논문은 악성코드가 사용하는 자기방어기법을 방식에 따라 분류하고, 악의적인 코드를 보호하는 방법의 일종인 패킹에 대해 소개하였으며, 패킹을 이용하는 악성코드를 보다 빠르게 분석할 수 있는 방안을 제시하였다. 패킹기법은 악의적인 코드를 은닉하고 실행 시에 복원하는 기술로서 패킹된 악성코드를 분석하기 위해서는 복원 후의 진입점을 찾는 것이 필요하다. 기존에는 진입점 수집을 위하여 악성코드의 패킹 관련 코드를 자세히 분석하여야만 했다. 그러나 본 논문에서는 이를 대신하여 악성코드를 생성한 표준 라이브러리 코드 일부를 탐색하는 방법을 제시하였다. 제시한 방안을 실제로 구현하여 보다 신속히 분석할 수 있음을 증명하였다.

평판형 유전체 장벽 방전 반응기에서 충진물질에 따른 아세토나이트릴의 분해 특성 (Decomposition of Acetonitrile Using a Planar Type Dielectric Barrier Discharge Reactor Packed with Adsorption and Catalyst Materials)

  • 김관태;송영훈;김석준
    • 한국대기환경학회지
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    • 제19권2호
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    • pp.157-165
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    • 2003
  • A combined process of non-thermal plasma and catalytic technique has been investigated to treat $CH_3$CN gas in the atmosphere. A planar type dielectric barrier discharge (DBD) reactor has been used to generate the non-thermal plasma that produces various chemically active species, such as O, N, OH, $O_3$, ion, electrons, etc. Several different types of the beads. which are Molecular Sieve (MS) 5A, MS 13X, Pt/alumina beads, are packed into the DBD reactor, and have been tested to characterize the effects of adsorption and catalytic process on treating the $CH_3$CN gas in the DBD reactor. The test results showed that the operating power consumption and the amounts of the by-products of the non-thermal plasma process can be reduced by the assistance of the adsorption and catalytic process.

A Capillary Electrochromatographic Microchip Packed with Self-Assembly Colloidal Carboxylic Silica Beads

  • Jeon, In-Sun;Kim, Shin-Seon;Park, Jong-Man
    • Bulletin of the Korean Chemical Society
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    • 제33권4호
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    • pp.1135-1140
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    • 2012
  • An electrochromatographic microchip with carboxyl-group-derivatized mono-disperse silica packing was prepared from the corresponding colloidal silica solution by utilizing capillary action and self-assembly behavior. The silica beads in water were primed by the capillary action toward the ends of cross-patterned microchannel on a cyclic olefinic copolymer (COC) substrate. Slow evaporation of water at the front of packing promoted the self-assembled packing of the beads. After thermally binding a cover plate on the chip substrate, reservoirs for sample solutions were fabricated at the ends of the microchannel. The packing at the entrances of the microchannel was silver coated to fix utilizing an electroless silver-plating technique to prevent the erosion of the packed structure caused by the sudden switching of a high voltage DC power source. The electrochromatographic behavior of the microchip was explored and compared to that of the microchip with bare silica packing in basic borate buffer. Electrophoretic migration of Rhodamine B was dominant in the microchip with the carboxyl-derivatized silica packing that resulted in a migration approximated twice as fast, while the reversible adsorption was dominant in the bare silica-packed microchip. Not only the faster migration rates of the negatively charged FITC-derivatives of amino acids but also the different migration due to the charge interaction at the packing surface were observed. The electrochromatographic characteristics were studied in detail and compared with those of the bare silica packed microchip in terms of the packing material, the separation potential, pH of the running buffer, and also the separation channel length.

Modified technique to fabricate a hollow light-weight facial prosthesis for lateral midfacial defect: a clinical report

  • Patil, Pravinkumar G.
    • The Journal of Advanced Prosthodontics
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    • 제2권3호
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    • pp.65-70
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    • 2010
  • Large oro-facial defects result from cancer treatment consequences in serious functional as well as cosmetic deformities. Acceptable cosmetic results usually can be obtained with a facial prosthesis. However, retention of a large facial prosthesis can be challenging because of its size and weight. This article describes prosthetic rehabilitation of a 57-year-old man having a right lateral mid-facial defect with intraoral-extraoral combination prosthesis. A modified technique to fabricate a hollow substructure in heat-polymerizing polymethyl-methacrylate to support silicone facial prosthesis was illustrated. The resultant facial prosthesis was structurally durable and light in weight facilitating the retention with magnets satisfactorily. This technique is advantageous as there is no need to fabricate the whole prosthesis again in case of damage of the silicone layer because the outer silicone layer can be removed and re-packed on the substructure if the gypsum-mold is preserved.

양친매성 다중층막의 전기적 도전성 및 전기적 특성 (The Electrical Conductivity and Electrochemical Characteristics of Amphiphilic Milecules Multilayer Film confined with Hetero Type)

  • 최인희;박수길;임기조;이주성
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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    • pp.269-272
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    • 1996
  • The electrochemical behavior of Ru complex and PD complex monolayer, deposited on conductive substrate by the Langmuir-Blodgett(LB) technique as monolayer and multilayer, has been studied by cyclic voltammetry. Monolayer films show stable reversible state. Atomic resolution imaging of LB highly-conductive, environmently stable organic films has been obtained by atomic force microscopy (AFM) showing their closely packed structure,

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AFM을 이용한 폴리술폰막의 표면구조와 상분리현상에 관한 연구 (Surface structure and phase separation mechanism of polysulfone membranes by AFM)

  • 김제영;이환광;김성철
    • 한국막학회:학술대회논문집
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    • 한국막학회 1998년도 추계 총회 및 학술발표회
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    • pp.103-105
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    • 1998
  • Asymmetric polymeric membranes prepared by the phase transition technique usually have either a top layer consisting of closely packed nodules or pores dispersed throughout the membrane surfaces. In this study, we present AFM image of a polysulfone membrane which show a clear evidence for the nodular structure and porous structure resulted from different phase separation mechanisms; spinodal decomposition and nucleation and growth. The surface morphology obtained by SEM and AFM was also compared.

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Purification of TiCl$_4$ by Adsorption Technique

  • Choi Q. Won;Lee Kyung Ae
    • Bulletin of the Korean Chemical Society
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    • 제9권1호
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    • pp.15-17
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    • 1988
  • Titanium tetrachloride is purified using adsorption column packed with activated silica gel. When 120 ml of titanium tetrachloride was passed through an adsorption column filled with 7 g silica gel, iron content in titanium tetrachloride has been reduced from 7 ppm to less than 1 ppm, and aluminum from 46 ppm to 11 ppm, while silicon content being unchanged at about 60 ppm.

고동아말감과 Glass ionomer-silver cement의 생물학적 평가에 관한 연구 (A BIOLOGICAL EVALUATION OF HIGH COPPER AMALGAM AND GLASS IONOMER-SILVER CEMENT)

  • 오병원;최호영;민병순;박상진
    • Restorative Dentistry and Endodontics
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    • 제15권2호
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    • pp.1-16
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    • 1990
  • This study was to evaluate the cytotoxic effect in vitro and the tissue response within the rat peritoneal cavity to high copper amalgam and glass ionomer-silver cement, suggested for use as a retrograde endodontic filling material. In the cytotoxicity experiment, the radioactively ($^{51}Cr$) labeled L929 mouse fibroblasts were employed to determine the relative cytotoxicity of two experimental materials. Those materials were evaluated immediately after set and after one and seven days setting. In the tissue response experiment, two experimental materials were to evaluate mean peritoneal cellular count, differential cell count and the content of silver and copper in pooled packed cells and eluate samples taken by peritoneal lavage technique, and compared with surgical control after one day. two, four and six weeks of implantation. The results were as following: 1. High copper amalgam exhibited significant cytotoxicity immediately after set but showed no sign of toxicity after one day and seven days setting materials. 2. Glass ionomer-silver cement showed no sign of toxicity immediately after set and after one day and seven days setting. 3. High copper amalgam and glass ionomer-silver cement groups produce no significant difference in the mean peritoneal cell count when compared with the surgical control group after one day, two and four weeks of implantation. Surgical control group exhibited significantly a greater cell count when compared with the High copper amalgam group after six weeks. 4. High copper amalgam group increased significantly in the percentage macrophages after four and six weeks of implantation when compared with surgical control group. 5. The trace metal analysis involved an increased silver content in the elutes and an increased copper content in the packed cells of high copper amalgam group, and an increased silver content in the packed cells and elutes of glass ionomer-silver cement group.

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