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On the Alternative Approach to Active Control

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Journal of Applied Mathematics and Physics 2018年第11期6卷 2303-2312页

作者： Vladimir V. Arabadzhi Division of Geophysical Research Institute of Applied Physics (RAS) Nizhny Novgorod Russia

Paper is devoted to problem of acoustical visibility reduction and gives brief description of alternative approach to active control. This approach allows satisfy jointly the four conditions: a) effective suppression of acoustical radiation and scattering caused by elastic body immersed in compressible medium (water);b) cloacking at any important temporal frequencies of ob-servant sound waves;c) cloacking at any important spatial frequencies or at any observation directions;(d) thickness of the masking shell is much smaller than the length of suppressed waves. Technological development gives more and more fast and miniature control elements and fast, accurate calculations. On the other hand, the lengths of waves to be damped are con-stant due to the constant conditions of their far propagation. The approach suggested uses operations of high space-time resolution for long waves controlling. Because the joint fulfillment of the conditions of acoustic support absence and the thinness of the shell and also the causality of control lead to the need to operate at frequencies of much higher than frequencies of waves to be damped. It is assumed that the incident waves are represented by a discrete set of plane waves of finite duration. Also it is assumed only that the characteristic spatial scale of the distribution of normal velocities on the surface of the protected body is limited from below. The boundary value problem with initial conditions is considered.

关键词： Boundary and Initial Conditions Flat Impact Flat Imprint Imprint Relaxa-tion Depth of Imprint Transparent Supportless Unidirectional Sources of Acoustical Wavelets Leading Edge of incident Wave Leading Pair of Micro-phones

Reduction of Interference Oscillations in Observing Intersubband Transitions in AlSb/GaSb Superlattices by Fourier Transform Infrared Spectroscopy

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Chinese Physics Letters 1995年第11期12卷 685-688页

作者： RU Guoping LI Aizhen State Key Laboratory of Functional Materials for Informatics Shanghai Institute of MetallurgyAcademia SinicaShanghai 200050

Intersubband transitions from L_(1) to L_(2) subbands in AISb/GaSb superlattices in the 8-18μm wavelength range are observed by employing normal-and oblique-incident Fourier transform infrared(FTIR)spectroscopic *** AlSb rather than GaSb as the buffer layer,interference oscillations in normal-incident FTlR spectra are significantly reduced,which facilitates one to distinguish intersubband transition *** the oblique-incident mode where a 45°thallium hexahedron is used for internal reflection,interference oscillations are eliminated,making it possible to observe weak intersubband transitions that cannot be distinguished in normal-incident absorption spectra.

关键词： spectra. incident transitions

THE DIFFRACTION SPOTS PRODUCED BY α-LilO_3 SINGLE CRYSTALS UNDER THE ACTION OF A DC FIELD

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Chinese Science Bulletin 1984年第12期29卷 1596-1601页

作者：王琇顾世杰 Department of physics Sichuan University Chengdu Institute of Physics Academia Sinica Beijing

α-LiIO8 crystals are non-linear optical materials with very good optical homogeneity, and have been widely used in the second hamonic generation （SHG） *** a DC field is applied along the c-axis of the crystal, the light beam passing through it will be diffracted, and the diffraction patterns, such as direct line or arc bands, starshaped streaks and spots vary with the directions of the incident light. The dif-

关键词： spots directions bands ACTION homogeneity satis distr latter incident bright

Structure and Oscillation of Underexpanded Jet

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Open Journal of Fluid Dynamics 2013年第2期3卷 85-91页

作者： Hiromasa Suzuki Masaki Endo Yoko Sakakibara Division of Electronic and Mechanical Engineering Tokyo Denki University Saitama Japan Graduate School of Advanced Science and Technology Tokyo Denki University Saitama Japan

In this study, flow characteristics are experimentally and numerically discussed, especially concerning shock-cell structure and oscillatory phenomena of supersonic jet. The jet becomes underexpanded when the nozzle pressure ratio of convergent nozzle exceeds the critical value. The underexpanded jet is not uniform because of the presence of the expansion wave, the compression wave and the shock wave formed in it. Many vortices are induced in jet boundary region by shearing stress generated between supersonic jet flow and atmospheric air. They interact with shock waves composing cell node of jet, which is closely related to a noise radiating from the jet. In experiment, flow field is visualized and the shape of cell structure is examined. Furthermore, frequency of vortex generation is measured. The jet is simulated using TVD scheme and the results are compared with the experimental ones. Distortion of cell structure caused by three dimensional oscillation of jet and behavior of vortices are discussed.

关键词： Underexpanded Jet Plate Shock incident Shock Visualization TVD Scheme

MAMNID: A Load Balance Network Diagnosis Model Based on Mobile Agents

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Journal of Information Security 2012年第4期3卷 281-294页

作者： Thomas Djotio Ndié Claude Tangha Guy Bertrand Fopak Lirima/Aloco University of Yaounde 1 Yaounde Cameroon Lirima/Masecness University of Yaounde 1 Yaounde Cameroon

In this paper, we propose MAMNID, a mobile agent-based model for networks incidents diagnosis. It is a load-balance and resistance to attack model, based on mobile agents to mitigate the weaknesses of centralized systems like that proposed by Mohamed Eid which consists in gathering data to diagnose from their collecting point and sending them back to the main station for analysis. The attack of the main station stops the system and the increase of the amount of information can equally be at the origin of bottlenecks or DDoS in the network. Our model is composed of m diagnostiquors, n sniffers and a multi-agent system (MAS) of diagnosis management of which the manager is elected in a cluster. It has enabled us not only to reduce the response time and the global system load by 1/m, but also make the system more tolerant to attacks targeting the diagnosis system.

关键词： Diagnosis incident Intrusion MAMNID MAS

A descriptive analysis of injury triage, surge of medical demand, and resource use in an university hospital after 8.12 Tianjin Port Explosion, China

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Chinese Journal of Traumatology 2015年第6期18卷 314-319页

作者： Guo-Qiang Li Shi-Ke Hou Xin Yu Xiang-Tao Meng Liang-Liang Liu Peng-BoYan Meng-Na Tian Shao-Lei Chen Hui-Juan Han Institute of Disaster and Emergency Rescue Medicine Pingjin Hospital Logistics College of The Chinese People's Armed Police Forces Tianjin 300162 China Department of Intensive Care Medicine Pingjin Hospital Logistics College of The Chinese People's Armed Police Forces Tianjin 300162 China contributed equally to this article as the co-firstauthor.

Objective： The 8.12 Tianjin Port Explosion in 2015 caused heavy casualties. Pingjin Hospital, an affiliated college hospital in Tianjin, China participated in the rescue activities. This study aims to analyze the emergency medical response to this event and share experience with trauma physicians to optimize the use of medical resource and reduce mortality of critical patients. Methods： As a trauma centre at the accident city, our hospital treated 298 patients. We retrospectively analyzed the data of emergency medical response, including injury triage, injury type, ICU patient flow, and medical resource use. Results： There were totally 165 deaths, 8 missing, and 797 non-fatal injuries in this explosion. Our hospital treated 298 casualties in two surges of medical demand. The first one appeared at 1 h after explosion when 147 wounded were received and the second one at 4 h when 31 seriously injured pa- tients were received, among whom 29 were transferred from Tianjin Emergency Center which was responsible for the scene injury triage. After reexamination and triage, only 11 cases were defined as critical ill patients, The over-triage rate reached as high as 62.07%. Seventeen patients underwent surgery and 17 patients were admitted to the intensive care unit, Conclusions： The present pre-hospital system is incomplete and may induce two surges of medical de- mand. The first one has a much larger number of casualties than predicted but the injury level is mild; while the second one has less wounded but almost all of them are critical patients. The over-triage rate is high. The hospital emergency response can be improved by an effective re-triage and implementation of a hosoital-wide damage control.

关键词： Mass casualty incident Over-triage Surge of medical demand Damage control

Investigation on acoustic holography reconstruction of scattering field of target

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Chinese Journal of Acoustics 2000年第1期19卷 44-59页

作者： BAO Xuemei HE Zuoyong (Dept. of Underwater Acoustical Eng., Harbin Engineering University Harbin 150001) Dept. of Underwater Acoustical Eng. Harbin Engineering University Harbin150001

The BEM-based (Boundary Element Method) scattering near field acoustic holography technique, which can be used to reconstruct the scattering sound field on the surface of a target and predict the whole scattering field from measured scattering near field, is described. First, the fundamental equations of this method and the related separation method for scattering field are brought forward. Then the problems such as the affect of different hologram to reconstructed result, the availability of singular value filter method and the applicability of separation method for scattering field are analyzed by means of numerical simulation.

关键词： holography holographic reconstructed Helmholtz coordinate superposition spherical gotten conveniently incident

A STUDY OF THE PRISM-GRATING COUPLER

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Chinese Science Bulletin 1983年第11期28卷 1460-1465页

作者： XU Dewei Changchun Institute of Physics Academia Sinica

The principal advantage of the prism coupler is that any gnide mode can be excited by properly selected incident angle of ***,the prism coupler has become a very useful device for investigating the properties of various thin film *** refractive index of the prism selected must be higher than the index of waveguide thin film material.

关键词： PRISM waveguide coupler refractive grating incident properly excited inequality mater

Disease Development Caused by Ascochyta rabiei on Chickpea Detached-Leaves in Petri Dishes

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American Journal of Plant Sciences 2012年第10期3卷 1369-1375页

作者： Nunung Harijati Philip J. Keane Department of Biology Brawijaya University Malang Indonesia Department of Botany LaTrobe University Melbourne Australia

A study using detached-leaves aimed to improve selection method. The improving method was done by scoring both disease symptom and lesion size. The research was begun by selecting agar concentration and dose of conidia that could distinguish response of very susceptible or resistant chickpea genotype. The result was used to determine disease severity (DS) and disease incident (DI) of eight genotypes that were previously tested in the field. Results of the tested agar concentration and dose of conidia showed that 1.5% and 2% agar were good to determine susceptible or resistant genotype;while 1 × 105 or 5 × 104 conidia dose was suitable for inoculation. The formula of DS (no. of leaflets in category × category value/Total no. of leaflets ×10) × 100, and DI (no. leaflets with pycnidial lesions + no. leaflets with necrotic lesions)/Total no. of leaflets × 100 successfully measured genotype response. The lesions development on detached leaves of the susceptible cultivar (Lasseter) began as circular, pale-colored areas, extending to the area covered by the drop of inoculum, then became light brown and finally dark brown. However, the response of resistant line (FLIP508) was restricted in area (and often confined to a tiny speck) surrounded by chlorosis or drying of the tissue.

关键词： Disease Severity (DS) Disease incident (DI) Ascochyta rabiei Chickpea Detached-Leaves