• Title/Summary/Keyword: model reduction technique

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On-Line/Off-Line Signature Schemes with Tight Security Reduction to the RSA Problem (RSA 문제와 동등한 안전성을 갖는 온라인/오프라인 서명 기법)

  • Choi, Kyung-yong;Park, Jong Hwan
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.28 no.2
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    • pp.327-338
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    • 2018
  • On-line/off-line signature is a technique for performing heavy computations required for signature generation in the off-line stage and completing the final signature by a simple operation in the online stage. This is suitable for application environments that require immediate signing responses to multiple users. In this paper, we propose two new on-line/off-line signature schemes based on RSA problem. The first technique can generate a signature with a fixed base exponentiation when signing online, and the second technique can complete an online signature with a very simple calculation such as a hash operation. The security of both signatures is based on the RSA problem, which is proven to be tightly secure without security loss in the random oracle model.

A Study on Ship Shape Design Optimization for RCS Reduction Using Taguchi Method (다구치 방법을 이용한 함정 RCS 형상최적화에 관한 연구)

  • Cho, Yong-Jin;Park, Dong-Hoon;Ahn, Jong-Woo;Park, Cheol-Soo
    • Journal of the Society of Naval Architects of Korea
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    • v.43 no.6 s.150
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    • pp.693-699
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    • 2006
  • This paper proposes a design optimization technique for ship RCS signature reductions using Taguchi method. The proposed technique comprises of i)evaluating initial RCS signatures, ii)defining critical areas which should be modified as design parameters, and threat factors which can't be controlled artificially as noise parameters, and finally iv)finding optimum parameters via analyzing signal to noise ratios for designated characteristics. We applied the technique to a model ship and found that it is suitable for radar stealth designs. In addition, the proposed technique is applicable to submarine designs against sonar threats.

Experimental Study on Consolidation and Bearing Capacity Characteristics of Marine Large Pack Pile (MLPP 공법의 압밀 및 지지력 특성에 관한 실험적 연구)

  • Lee, Sang-Ik;Park, Yong-Won;Ihm, Chul-Woong;Kim, Il-Gon
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.272-279
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    • 2005
  • This paper introduces a new method of improvement for marine soft ground, MLPP(Marine Large Pack Pile). The MLPP is a reinforcement technique for the conventional SCP or GCP piles by confining with geotextile pack. A pilot project at Busan New Port site and laboratory model tests were carried out to investigate the settlement reduction and bearing capacity enhancement effect of pack pile. The results of field and laboratory tests show that MLPP method can be a safe and economic alternative method for SCP and GCP.

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A Study on the Reduction of Detent Force caused by End-Effect for Moving Coil Type PMLSM Using Auxiliary-teeth (보조치를 이용한 가동 코일형 PMLSM의 단부효과에 의한 Detent Force 저감에 관한 연구)

  • Jeong, Su-Kwon;Zhou, Jian-Pei;Lee, Dong-Yeup;Kim, Gyu-Tak
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.55 no.9
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    • pp.459-464
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    • 2006
  • The detent force by end-effect has an undesired influence on moving coil type Permanent Magnet Linear Synchronous Motor(PMLSM). So, the reduction of detent force by end-effect is especially required for the improvement of thrust characteristics. In this paper, in order to reduce detent force by end-effect, the auxiliary-teeth is installed at the end part of mover. It is also analyzed by Finite Element Analysis(FEA) and optimized by using neural network. By comparison, the detent force is reduced about 41.4[%] comparing to that of basic model.

Feedback Controller Design for a In-plane Gimbaled Micro Gyroscope Using H-infinity and State Weighted Model Reduction Techniques

  • Song, Jin-Woo;Lee, Jang-Gyu;Taesam Kang;Kim, Yong-Kweon;Hakyoung Chung;Chang, Hyun-Kee
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.39.3-39
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    • 2002
  • In this paper, presented is a feedback control loop, for an in-plane gimbaled micro gyroscope based on methodology and state weighted model reduction technique. The micro gyroscope is the basic inertial sensors. To improve the performances such as stability, wide dynamic range, bandwidth and especially robustness, it is necessary to design a feedback control loop, which must be robust, because the manufacturing process errors can be large. Especially, to obtain wide bandwidth, the feedback controller is indispensable, because the gyroscope is high Q factor system and has small open loop bandwidth. Moreover, the feedback controller reduces the effect...

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Wind loading characteristics of super-large cooling towers

  • Zhao, L.;Ge, Y.J.
    • Wind and Structures
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    • v.13 no.3
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    • pp.257-273
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    • 2010
  • The aerodynamic and aero-elastic model tests of the China''s highest cooling tower has been carried out in the TJ-3 Boundary Layer Wind Tunnel of Tongji University. By adopting a scanivalve system, the external wind pressure is firstly measured on $12{\times}36$ taps for a single tower, two and four grouped towers under the condition of both smooth flow and the boundary layer due to surrounding geographic and building topography. The measurements of internal wind pressure distribution of $6{\times}36$ taps are taken for a single tower under the various ventilation ratios ranging from 0% to 100% of stuffing layers located at the bottom of the tower. In the last stage, the wind tunnel tests with an aero-elastic model are carefully conducted to determine wind-induced displacements at six levels (each with eight points) with laser displacement sensors. According to the measurement results of wind pressure or vibration response, the extreme aerodynamic loading values of the single or grouped towers are accordingly analyzed based on probability correlation technique.

Active Control of Earthquake Responses using LQG/LTR Method (LQ/LTR 제어기법을 이용한 지진응답의 능동적 진동제어)

  • 고현무
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1999.10a
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    • pp.244-250
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    • 1999
  • Active vibration control method for the reduction of vibration of structures have been developed. For the application of real structures active control system that has robustness must be designed because the mathematical model incompletely described has intrinsically modeling error. In this research we propose LQG/LTR method in designing control system with robustness. A combination of acceleration feedback and model-order reduction technique is used for the application of real structures and the computation efficiency. In case of such structures as the building and the tower the inter-story relative displacements represent an important constraint in seismic design. Therefore selection method of design parameters is also proposed in order to reduce the inter-story relative displacements.

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Short Communication of Novel Application of Food Irradiation

  • Cheorun Jo;Lee, Ju-Wosn;Byunl, Myung-Woo
    • Preventive Nutrition and Food Science
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    • v.6 no.4
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    • pp.253-256
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    • 2001
  • Irradiation of food is not only used for sanitation purposes but can be used for processing techniques to reduce or eliminate toxic or undesirable compounds on food. Irradiation wag effective to reduce the allergenicity of food by modification of the structure of proteins causing allergy reactions. Volatile N-nitrosmaine was reduced or eliminated by irradiation in the model system study and the breakdown products by irradiation did not recombine under human stomach conditions (pH 2,3, and 4,37$^{\circ}C$). The possibility of residual chlorophyll b reduction by irradiation was also found, and the model study indicated that irradiation be used to destroy chlorophyll b, resulting in protection from photooxidation in oil without acceleration of lipid oxidation during irradiation. In this paper, several on-going research projects for the application of food irradiation as a new processing technique are introduced, including reduction of food allergens, breakdown of volatile N-nitrosamine and residual chlorophyll b.

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DNA Based Cloud Storage Security Framework Using Fuzzy Decision Making Technique

  • Majumdar, Abhishek;Biswas, Arpita;Baishnab, Krishna Lal;Sood, Sandeep K.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.7
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    • pp.3794-3820
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    • 2019
  • In recent years, a cloud environment with the ability to detect illegal behaviours along with a secured data storage capability is much needed. This study presents a cloud storage framework, wherein a 128-bit encryption key has been generated by combining deoxyribonucleic acid (DNA) cryptography and the Hill Cipher algorithm to make the framework unbreakable and ensure a better and secured distributed cloud storage environment. Moreover, the study proposes a DNA-based encryption technique, followed by a 256-bit secure socket layer (SSL) to secure data storage. The 256-bit SSL provides secured connections during data transmission. The data herein are classified based on different qualitative security parameters obtained using a specialized fuzzy-based classification technique. The model also has an additional advantage of being able to decide on selecting suitable storage servers from an existing pool of storage servers. A fuzzy-based technique for order of preference by similarity to ideal solution (TOPSIS) multi-criteria decision-making (MCDM) model has been employed for this, which can decide on the set of suitable storage servers on which the data must be stored and results in a reduction in execution time by keeping up the level of security to an improved grade.

Development of Predictive Model for Length of Stay(LOS) in Acute Stroke Patients using Artificial Intelligence (인공지능을 이용한 급성 뇌졸중 환자의 재원일수 예측모형 개발)

  • Choi, Byung Kwan;Ham, Seung Woo;Kim, Chok Hwan;Seo, Jung Sook;Park, Myung Hwa;Kang, Sung-Hong
    • Journal of Digital Convergence
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    • v.16 no.1
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    • pp.231-242
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    • 2018
  • The efficient management of the Length of Stay(LOS) is important in hospital. It is import to reduce medical cost for patients and increase profitability for hospitals. In order to efficiently manage LOS, it is necessary to develop an artificial intelligence-based prediction model that supports hospitals in benchmarking and reduction ways of LOS. In order to develop a predictive model of LOS for acute stroke patients, acute stroke patients were extracted from 2013 and 2014 discharge injury patient data. The data for analysis was classified as 60% for training and 40% for evaluation. In the model development, we used traditional regression technique such as multiple regression analysis method, artificial intelligence technique such as interactive decision tree, neural network technique, and ensemble technique which integrate all. Model evaluation used Root ASE (Absolute error) index. They were 23.7 by multiple regression, 23.7 by interactive decision tree, 22.7 by neural network and 22.7 by esemble technique. As a result of model evaluation, neural network technique which is artificial intelligence technique was found to be superior. Through this, the utility of artificial intelligence has been proved in the development of the prediction LOS model. In the future, it is necessary to continue research on how to utilize artificial intelligence techniques more effectively in the development of LOS prediction model.