• 제목/요약/키워드: Novel engineering

검색결과 8,101건 처리시간 0.032초

A Novel System for Detecting Adult Images on the Internet

  • Park, Jae-Yong;Park, Sang-Sung;Shin, Young-Geun;Jang, Dong-Sik
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제4권5호
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    • pp.910-924
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    • 2010
  • As Internet usage has increased, the risk of adolescents being exposed to adult content and harmful information on the Internet has also risen. To help prevent adolescents accessing this content, a novel detection method for adult images is proposed. The proposed method involves three steps. First, the Image Of Interest (IOI) is extracted from the image background. Second, the IOI is distinguished from the segmented image using a novel weighting mask, and it is determined to be acceptable or unacceptable. Finally, the features (color and texture) of the IOI or original image are compared to a critical value; if they exceed that value then the image is deemed to be an adult image. A Receiver Operating Characteristic (ROC) curve analysis was performed to define this optimal critical value. And, the textural features are identified using a gray level co-occurrence matrix. The proposed method increased the precision level of detection by applying a novel weighting mask and a receiver operating characteristic curve. To demonstrate the effectiveness of the proposed method, 2850 adult and non-adult images were used for experimentation.

Novel Brazing법에 의한 Al의 공정접합에 관한 연구 (A Study of Eutectic Bonding for Aluminium using Novel Brazing Process)

  • 정병호;김무길;이성열
    • Journal of Advanced Marine Engineering and Technology
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    • 제24권1호
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    • pp.59-66
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    • 2000
  • To investigate the optimum brazing condition, variation of bonded structure and mechanical properties of novel brazed pure Al with bonding condition (brazing temperature, time and Si/flux ratio) was studied. A basic study of the bonding mechanism was also examined. The optimum brazing condition was obtained at $590^{\circ}$ for 2 minutes and the bonded structure showed that it is composed of almost entirely eutectic Al-Si with near eutectic composition. At higher brazing temperature $630^{\circ}$, hypoeutectic Al-Si structure was observed in the bonded area and resulted in erosion of base metal. The thickness of eutectic layer formed in optimum brazing temperature increased linearly with the square root of time, showing a general diffusion controlled process. The ultimate tensile strength of bonded joint brazed at an optimum brazing condition was about 60% of base metal and its fracture surface showed a brittle mode.

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Aerodynamic Design of a Novel Low-Reynolds-Number Airfoil for Near Space Propellers

  • Zhang, Shunlei;Yang, Xudong;Song, Bifeng;Song, Wenping
    • International Journal of Aerospace System Engineering
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    • 제2권1호
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    • pp.53-57
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    • 2015
  • For improving the efficiency of near space propellers working over 20km, performances of their streamwise sections, i.e. low-Reynolds-number airfoils which work at $10^4-10^5$ Reynolds numbers, are significant. Based on the low-Reynolds-number CFD technology, this paper designs a novel low-Reynolds-number airfoil. Unsteady characteristics of the laminar separation bubble on novel airfoil and a typical conventional airfoil are studied numerically, and the Reynolds number effect is investigated. Results show that at $10^4-10^5$ Reynolds numbers, unsteady aerodynamic characteristics of the novel airfoil are severely weakened and its lift-to-drag ratio can increase about 100%.

Efficient computational method for joint distributions of heights and periods of nonlinear ocean waves

  • Wang, Yingguang
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제11권1호
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    • pp.597-605
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    • 2019
  • This paper proposes a novel method for efficient prediction of joint distributions of heights and periods of nonlinear ocean waves. The proposed novel method utilizes a transformed linear simulation which is based on a Hermite transformation model where the transformation is chosen to be a monotonic cubic polynomial, calibrated such that the first four moments of the transformed model match the moments of the true process. This proposed novel method is utilized to predict the joint distributions of wave heights and periods of a sea state with the surface elevation data measured at the Gulfaks C platform in the North Sea, and the novel method's accuracy and efficiency are favorably validated by using comparisons with the results from an empirical joint distribution model, from a linear simulation model and from a second-order nonlinear simulation model.

Enhanced Electrical Performance of SiZnSnO Thin Film Transistor with Thin Metal Layer

  • Lee, Sang Yeol
    • Transactions on Electrical and Electronic Materials
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    • 제18권3호
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    • pp.141-143
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    • 2017
  • Novel structured thin film transistors (TFTs) of amorphous silicon zinc tin oxide (a-SZTO) were designed and fabricated with a thin metal layer between the source and drain electrodes. A SZTO channel was annealed at $500^{\circ}C$. A Ti/Au electrode was used on the SZTO channel. Metals are deposited between the source and drain in this novel structured TFTs. The mobility of the was improved from $14.77cm^2/Vs$ to $35.59cm^2/Vs$ simply by adopting the novel structure without changing any other processing parameters, such as annealing condition, sputtering power or processing pressure. In addition, stability was improved under the positive bias thermal stress and negative bias thermal stress applied to the novel structured TFTs. Finally, this novel structured TFT was observed to be less affected by back-channel effect.

A Novel Cooperative Spectrum Sensing Algorithm in Cognitive Radio Systems

  • Zheng, Xueqiang;Wang, Jinlong;Wu, Qihui;Shen, Liang
    • Journal of Communications and Networks
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    • 제11권2호
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    • pp.115-121
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    • 2009
  • In cognitive radio (CR) systems, cognitive users can use the frequency bands when the primary users are not present. Hence, reliable detection of available spectrum is foundation of cognitive radio technology. To ensure unimpaired operation of primary users, cooperative spectrum sensing is needed. To reduce the network overhead of cooperative spectrum sensing, a novel cooperative spectrum sensing algorithm based on credibility is proposed. In particular, the close-form expressions for probability of detection and false-alarm are derived for the novel algorithm, and expression for the average overhead used for cooperation is given. The thresholds design method for the algorithm is also discussed. The conclusion is proved by computer simulations.

Design of a Novel Multi-Dimensional HCOC Multi-code Spread Spectrum System Using Pre-coding Technique for High Speed Data Transmission of DS-CDMA

  • Kong, Hyung-Yun;Lee, Dong-Un
    • Journal of electromagnetic engineering and science
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    • 제7권1호
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    • pp.1-6
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    • 2007
  • Recently, Mc(Multi-code) modulation/demodulation(modem) technique has been explored for high speed data transmission in wireless environment. The conventional Mc modem generates some side effects such as allocating Walsh codes, which motivates to propose a novel Mc modem method with sub-code. Our proposed system should expanded the size of sub-code to provide high-rate data transmission, which also affect adversely to the performance of the system with high PAPR(Peak to Average Power Ratio). Thus, in this paper, we propose a novel pre-coded Multi-Dimensional HCOC(High Capacity Orthogonal Code) Mc modem technique to reduce the high PAPR, which enables the performance improvement. This proposed system can be easily designed by concatenating HCOC Mc modem with the generic Mc modem. The pre-coding technique that is used in this paper is CAC(Constant Amplitude Coding), that helps the system maintain the constant transmission power and reduce the maximum transmission power.

Goertzel 알고리즘을 이용한 새로운 단독운전 방지 기법 (A novel anti-islanding method using Goertzel Algorithm)

  • 원동조;김재형;김준구;원충연;이태원
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2009년도 정기총회 및 추계학술대회 논문집
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    • pp.299-301
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    • 2009
  • In this paper, a novel anti-islanding method of DC-AC single phase inverter is proposed. The inverter injects a little harmonic current with the output current of a PCS(Power Conditioning System). When the islanding condition is occurred, the voltage harmonic components appear on the output voltage of the PCS due to the injection of a little harmonic current. So, the PCS detects the voltage harmonic components using the Goertzel algorithm, and then the PCS decides that the islanding condition is occurred. When the PCS recognizes the islanding condition, the PCS are stopped. The proposed a novel anti-islanding method is analyzed, and its validity is proven through simulation.

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Cyclosophoraose as a Novel Chiral Stationary Phase for Enantioseparation

  • JUNG, YUN-JUNG;LEE, SANG-HOO;PAIK, SEUNG-R.;JUNG, SEUN-HO
    • Journal of Microbiology and Biotechnology
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    • 제14권6호
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    • pp.1338-1342
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    • 2004
  • Cyclosophoraoses (Cys), cyclic ${\beta}-(1{\rightarrow}2)-D-glucans$ produced by Rhizobium meliloti 2011, were used as a novel chiral stationary phase for the enantiomeric separation. A novel Cys stationary phase, chemically immobilized onto porous silica via aminopropyltrimethoxysilane as a molecular linker, showed good separation for each racemate of bupivacain (separation factor, $\alpha$=1.3), propranolol ($\alpha$=1.3), and fenoprofen ($\alpha$=2.9), respectively, under the mobile phase of water: methanol (80:20, v/v) at a constant flow rate of 0.9 ml/min at pH7.

Nonlinear Observer-based Control of Synchronous Machine Drive System

  • Sundrica, Marijo;Erceg, Igor;Maljkovic, Zlatko
    • Journal of Electrical Engineering and Technology
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    • 제10권3호
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    • pp.1035-1047
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    • 2015
  • Starting from a new dynamic system description novel synchronous machine deterministic observers are proposed. Reduced and full order adaptive observer variations are presented. Based on the feedback linearization control law and the use of deterministic observer a novel control system is built. It meets the requirements of high performance tracking system. Adaptivity to stator and rotor resistance and the torque sensorless application is included. The comparison of the proposed novel control with conventional linear and nonlinear control systems is discussed. The given simulational study includes complete drive system integration.