Modified attitude pursuit guidance law for low-cost missiles using strap-down seekers

Attitude pursuit guidance law is suitable for low cost missiles.A strap-down seeker is used to achieve this guidance law.The additional angles of attack or sideslip caused by wind and by control system are considered as two disturbing factors which make attitude pursuit law impossible.Therefore,general attitude pursuit guidance law did not account for this two disturbing factors,because with those disturbing factors,it is difficult to apply.To solve the problem,the principle of strap-down seeker detecting target is investigated,the mathematical control model is established,then a modified attitude pursuit guidance law which employs the angular correction for those two disturbing factors is presented.It is proved that the modified attitude pursuit guidance law is appropriated to both in the presence of the additional angle of attack or sideslip via the simulations with the mathematical control model and Monte-Carlo method.

利用Greenseeker法诊断甜菜氮素营养状况

利用Green Seeker法对不同氮素运筹下甜菜冠层归一化植被指数(normalized difference vegetation index,简称NDVI)进行测定,并分析甜菜叶面积指数(leaf area index,简称LAI)、比叶重(specific leaf weight,简称SLW)、叶片叶绿素含量以及全氮含量的变化。结果表明,甜菜冠层NDVI与叶片全氮含量呈极显著正相关,与叶片其他指标相关性不显著,NDVI与叶片全氮含量的拟合度在叶丛快速增长期最高。因此可见,利用Green Seeker法获取的NDVI能够反映甜菜叶片的氮素营养状况,Green Seeker法可以作为甜菜氮素营养快速无损检测的手段。

Internet addiction and problematic Internet use: A systematic review of clinical research

AIM: To provide a comprehensive overview of clinical studies on the clinical picture of Internet-use related addictions from a holistic perspective. A literature search was conducted using the database Web of Science.METHODS: Over the last 15 years, the number of Internet users has increased by 1000%, and at the same time, research on addictive Internet use has proliferated. Internet addiction has not yet been understood very well, and research on its etiology and natural history is still in its infancy. In 2013, the American Psychiatric Association included Internet Gaming Disorder in the appendix of the updated version of the Diagnostic and Statistical Manual for Mental Disorders(DSM-5) as condition that requires further research prior to official inclusion in the main manual, with important repercussions for research and treatment. To date, reviews have focused on clinical and treatment studies of Internet addiction and Internet Gaming Disorder. This arguably limits the analysis to a specific diagnosis of a potential disorder that has not yet been officially recognised in the Western world, rather than a comprehensive and inclusive investigation of Internet-use related addictions(including problematic Internet use) more generally. RESULTS: The systematic literature review identified a total of 46 relevant studies. The included studies used clinical samples, and focused on characteristics of treatment seekers and online addiction treatment. Four main types of clinical research studies were identified, namely research involving(1) treatment seeker characteristics;(2) psychopharmacotherapy;(3) psychological therapy; and(4) combined treatment. CONCLUSION: A consensus regarding diagnostic criteria and measures is needed to improve reliability across studies and to develop effective and efficient treatment approaches for treatment seekers.

Suicide in Immigrants: An Overview

Globalization in the Internet era has rendered job mobility and migration frequent and important social phenomena, with implications at several different levels of societies. In addition, migration, either voluntary or forced, is accompanied by significant changes in suicide ideation, frequency of suicide attempts and rates of suicide of people that migrate compared to the host country. However, several different peculiarities render the interpretation of the interaction of migration-suicidality as quite complex. This article provides an overview of the most significant aspects that contribute to this complexity, in order to provide the reader with a road map for better orientation in a world of rapidly changing landscapes.

Human Immunodeficiency Virus and Immunological Profiles among Suspected Tuberculosis Cases in Mombasa County, Kenya

Background: Human immunodeficiency virus (HIV) is a major public health concern and cause of death globally including Kenya. HIV infection is characterised by CD4+ lymphocyte depletion manifested through the loss of the immune response capacity. Aim: This study aimed to determine the prevalence of HIV infection and CD4+T cell counts among suspected tuberculosis (TB) cases seeking healthcare at TB clinics in Mombasa County, Kenya. Study Design: Hospital and laboratory based cross-sectional study was carried between May 2011 and November 2013 in Coast General Referral Hospital, Tudor, Port-Reitz, Mlaleo, Likoni and Mikandani districts and sub-districts hospitals. Methodology: A total of 500 suspected TB cases (271 males and 229 females) were screened for HIV infection using Trinity Biotech Uni-GoldTM test and positives confirmed with the enzyme- linked immunosorbent assay. CD4+ and CD8+T cells were analyzed using a BD FACS Count flow cytometer. A questionnaire was used to collect demographic data of the participants. Results: In total, 127 (25.4%) of the suspects were HIV infected 55.1% females and 44.9% males. Females were significantly affected than males (OR = 0.78;95% CI: 0.44 - 1.37;p = 0.042). The majority (36.2%) of the HIV cases were in the 25 - 34 years age group followed by the 35 - 44 (33.9%), 45 - 54 (16.5%) and 18 - 24 (7.1%) age groups, respectively. Widowed (AOR = 6.14;95% CI: 1.53 - 20.54;p < 0.033), alcohol (AOR = 2.83;95% CI: 1.71 - 4.87;p < 0.001) and condom use (AOR = 2.31;95% CI: 1.62 = 4.71;p < 0.002) were risk factors associated with HIV infection. The mean CD4 cell count was 333.27 ± 150.59 cells/mm3 and it was higher in males (343.05 ± 149.33 cells/mm3) than females (325.93 ± 152.92 cells). The mean values of white blood cells (5.9 ± 2.42) × 109/l), packed cell value (34.1% ± 4.3%), platelets (195.16 ± 88.7) × 109/l and erythrocyte sedimentation rate (102.0 ± 17.4 mm/hr) were significantly lower than the control group (p < 0.05). Conclusion: The prevalence of HIV infection among suspected TB cases was 25.4% which was higher than the current national average HIV prevalence of 6.9%. Lower CD4+ lymphocyte count was found to be the only predicting factor for HIV. There was a significant relationship between CD4/ESR and HIV infection.

小麦不同生育期水肥管理与产量模型构建

【目的】建立小麦在不同生育期的水肥管理与产量的关系模型。【方法】用主动遥感仪器Green seeker进行检测小麦冠层归一化植被指数(NDVI)以及比值植被指数(RVI),解析小麦冠层植被指数与生长状况的变化规律;分析NDVI、RVI与实际产量关系,建立小麦产量预测模型;最终以NDVI、RVI作为过渡参数,反演产量与小麦在不同生育期的水肥管理的最佳模型。【结果】小麦水肥一体化管理直接影响小麦产量,不同生育期水肥一体化小麦生长模型和植被指数小麦估产模型的标准误差都小于0.05。【结论】建立了小麦不同生育期的产量与水肥一体化管理模型。

Seeker optimization algorithm:a novel stochastic search algorithm for global numerical optimization

A novel heuristic search algorithm called seeker op- timization algorithm （SOA） is proposed for the real-parameter optimization. The proposed SOA is based on simulating the act of human searching. In the SOA, search direction is based on empir- ical gradients by evaluating the response to the position changes, while step length is based on uncertainty reasoning by using a simple fuzzy rule. The effectiveness of the SOA is evaluated by using a challenging set of typically complex functions in compari- son to differential evolution （DE） and three modified particle swarm optimization （PSO） algorithms. The simulation results show that the performance of the SOA is superior or comparable to that of the other algorithms.

Photoelectric detection technology of laser seeker signals

The measurement of the rolling angle of the projectile is one of the key technologies for the terminal correction projectile.To improve the resolution accuracy of the rolling angle in the laser seeker weapon system, the imaging model of the detector, calculation model of the position and the signal-to-noise ratio(SNR) model of the circuit are built to derive both the correlation between the resolution error of the rolling angle and the spot position, and the relation between the position resolution error and the SNR. Then the influence of each parameter on the SNR is analyzed at large,and the parameters of the circuit are determined. Meanwhile, the SNR and noise voltage of the circuit are calculated according to the SNR model and the decay model of the laser energy. Finally,the actual photoelectric detection circuit is built, whose SNR is measured to be up to 53 d B. It can fully meet the requirement of0.5° for the resolution error of the rolling angle, thereby realizing the analysis of critical technology for photoelectric detection of laser seeker signals.

New method for passive radar seeker to antagonize non-coherent radar decoy

Using super resolution direction of arrival（DOA） estimation algorithm to reduce the resolution angle is an effective method for passive radar seeker（PRS） to antagonize non-coherent radar decoy.Considering the power and correlation property between radar and non-coherent decoy,an improved subspace DOA estimation method based on traditional subspace algorithm is proposed.Because this new method uses the invariance property of noise subspace,compared with traditional MUSIC algorithm,it shows not only better resolution in condition of closely spaced sources,but also superior performance in case of different power or partially correlated sources.Using this new method,PRS can distinguish radar and non-coherent decoy with good performance.Both the simulation result and the experimental data confirm the performance of the method.

基于Green Seeker对小麦植被指数与产量形成模型的研究

小麦的产量受品种、光照、昼夜温差、降水、病虫害等自然灾害和耕地面积等综合因素的影响。通过小麦不同品种、不同灌溉方式、不同播种方式在小麦整个生育期的监测,研究小麦在不同的生长环境下建立与小麦的产量关系尤为重要。小麦冠层归一化植被指数(NDVI)以及比值植被指数(RVI)的变化情况,可利用主动遥感仪器——Green Seeker进行检测。对测量数据进行筛选,建立回归模型,解析小麦冠层植被指数与产量的变化规律,寻找基于NDVI和RVI与小麦产量的最佳估算模型,并验证小麦产量预测模型的有效性,对小麦产量预测的公式进行分析。

Microbiological screenings for infection control in unaccompanied minor refugees： the German Armed Forces Medical Service＇s experience

Background:The German Military Medical Service contributed to the medical screening of unaccompanied minor refugees(UMRs)coming to Germany in 2014 and 2015.In this study,a broad range of diagnostic procedures was applied to identify microorganisms with clinical or public health significance.Previously,those tests had only been used to screen soldiers returning from tropical deployments.This instance is the first time the approach has been studied in a humanitarian context.Methods:The offered screenings included blood cell counts,hepatitis B serology and microscopy of the stool to look for protozoa and worm eggs as well as PCR from stool samples targeting pathogenic bacteria,protozoa and helminths.If individuals refused certain assessments,their decision to do so was accepted.A total of 219 apparently healthy male UMRs coming from Afghanistan,Egypt,Somalia,Eritrea,Syria,Ghana,Guinea,Iran,Algeria,Iraq,Benin,Gambia,Libya,Morocco,Pakistan,and Palestine were assessed.All UMRs who were examined at the study department were included in the assessment.Results:We detected decreasing frequencies of pathogens that included diarrhoea-associated bacteria[Campylobacter(C.)jejuni,enteropathogenic Escherichia(E.)coli(EPEC),enterotoxic E.coli(ETEC),enteroaggregative E.coli(EAEC),enteroinvasive E.coli(EIEC)/Shigella spp.),Giardia(G.)duodenalis,helminths(comprising Schistosoma spp.,Hymenolepis(H.)nana,Strongyloides(S.)stercoralis]as well as hepatitis B virus.Pathogenic microorganisms dominated the samples by far.While G.duodenalis was detected in 11.4%of the assessed UMRs,the incidence of newly identified cases in the German population was 4.5 cases per 100,000 inhabitants.Conclusion:We conclude that the applied in-house PCR screening systems,which have proven to be useful for screening military returnees from tropical deployments,can also be used for health assessment of immigrants from the respective sites.Apparently healthy UMRs may be enterically colonized with a broad variety of pathogenic and apathogenic microorganisms.Increased colonization rates,as shown for G.duodenalis,can pose a hygiene problem in centralized homes for asylum seekers.

The Echo Modelling and Simulation of the Semi-Active Radar Seeker against a Sea Skimming Target

This paper has proposed a new modelling and simulating technique for the echo of the semi-active radar seeker against the sea skimming target. The echo modelling is based on the electromagnetic scattering mechanisms. A modified Four-path model based on the radar detection scene is used to describe the multipath scattering between the target and rough sea surface. A Facet-based Small Slope Approximation (FBSSA) method is employed to calculate the scattering from the sea surface. The Physical Optics (PO) and the Equivalent Edge Current (EEC) Method is used to calculate the target scattering. In the echo simulations. The results present the original echo and the echo processed by the signal processing procedures, where the clutter and multipath effect can be observed.

Signal processing method of a novel polarized array radar seeker

This paper proposes a novel polarized radar seeker based on the polarized antenna array. A fully polarized signal processing method for the proposed radar seeker is studied under the environments with electromagnetic interferences. A dual polarized antenna array is employed to transmit and receive the radar signals. The instantaneous polarization signal processing technique is used to detect and recognize the targets. The direction of arrival （DOA） of the target is measured through the spatial spectrum with high resolution for the polarized array radar seeker system. The fully polarized signal model of the polarized array radar seeker is formulated and a specific signal processing algorithm is expounded. The theoretical research and numerical simulation results demonstrate that the proposed radar seeker has good performances in target detection and electronic warfare. The research results can provide an effective technical approach to develop and research the new generation radar seeker.

Influence of roll-pitch seeker DRR and parasitic loop on Lyapunov stability of guidance system

This paper focuses on the influence of the disturbance rejection rate(DRR)and parasitic loop parameters on the stability domain of the roll-pitch seeker's guidance system.The DRR models of the roll-pitch seeker caused by different types of disturbance torques and the scale deviation of different sensors are established.The optimal DRR model of the roll-pitch seeker,which contains the scale deviation model,is proposed by formula derivation.The model of the roll-pitch seeker's guidance system is established and equivalently simplified by the dimensionless method.The Lyapunov stability criterion for stability analysis of the guidance system is given by means of the passivity theorem and related definitions and lemmas.A simplified model of the roll-pitch seeker's guidance system,which is suitable for the Lyapunov stability criterion,is established by formula derivation and equivalent transformation.Three conditions that satisfy the Lyapunov stability criterion are obtained.Mathematical simulation with Nyquist plots is used to analyze the influence of different DRR parameters on the stability domain of the roll-pitch seeker's guidance system.Simulation results of this paper can provide reference for the stability analysis of systems related to the roll-pitch seeker.

论华东野战军的首战及其意义

论华东野战军的首战及其意义陈建洲建国以来．我国许多史书和高校教材中，关于华东野战军集中其主力所进行的一个运动歼灭战──宿北战役．有某些相互矛盾的记述．８０年代，笔者曾在编辑（宿北战役资料选》之后，发表（试论宿北战役的胜利及其重要意义）一文，阐述该战役...

Seeker Optimization with Deep Learning Enabled Sentiment Analysis on Social Media;

World Wide Web enables its users to connect among themselves through social networks,forums,review sites,and blogs and these interactions produce huge volumes of data in various forms such as emotions,sentiments,views,etc.Sentiment Analysis(SA)is a text organization approach that is applied to categorize the sentiments under distinct classes such as positive,negative,and neutral.However,Sentiment Analysis is challenging to perform due to inadequate volume of labeled data in the domain of Natural Language Processing(NLP).Social networks produce interconnected and huge data which brings complexity in terms of expanding SA to an extensive array of applications.So,there is a need exists to develop a proper technique for both identification and classification of sentiments in social media.To get rid of these problems,Deep Learning methods and sentiment analysis are consolidated since the former is highly efficient owing to its automatic learning capability.The current study introduces a Seeker Optimization Algorithm with Deep Learning enabled SA and Classification(SOADL-SAC)for social media.The presented SOADL-SAC model involves the proper identification and classification of sentiments in social media.In order to attain this,SOADL-SAC model carries out data preprocessing to clean the input data.In addition,Glove technique is applied to generate the feature vectors.Moreover,Self-Head Multi-Attention based Gated Recurrent Unit(SHMA-GRU)model is exploited to recognize and classify the sentiments.Finally,Seeker Optimization Algorithm(SOA)is applied to fine-tune the hyperparameters involved in SHMA-GRU model which in turn enhances the classifier results.In order to validate the enhanced outcomes of the proposed SOADL-SAC model,various experiments were conducted on benchmark datasets.The experimental results inferred the better performance of SOADLSAC model over recent state-of-the-art approaches.

Line-of-sight rates extraction of roll-pitch seeker under anti-infrared decoy state

In this paper,the method of extracting guidance information such as the line-of-sight(LOS)rates under the anti-infrared decoy state for the roll-pitch seeker is researched.Coordinate systems which are used to describe the angles transform are defined.The LOS angles reconstruction model of the roll-pitch seeker in inertial space is established.A Kalman filter model for extracting LOS rates of the roll-pitch seeker is proposed.In this model,the target performs constant acceleration(CA)model maneuvers.The error model of LOS rates extraction under infrared decoy state is established.Several existing methods of extracting LOS rates under anti-infrared decoy state are listed in this paper.Different from the existing methods,a novel method that uses extrapolated values of target accelerations as filter measurements is proposed to solve the guidance information extraction problem under the anti-infrared decoy state.Numerical simulations are conducted to verify the effectiveness of the proposed method under different target maneuvering models such as the CA model,the CA extended model and the singer model.The simulation results show that the proposed method of extracting guidance information such as LOS rates for the rollpitch seeker under the anti-infrared decoy state is effective.

Brillouin scattering spectrum character extraction based on genetic algorithm and seeker optimization algorithm

A new hybrid optimization method based on genetic algorithm(GA)and seeker optimization algorithm(SOA)is presented in this paper.The hybrid algorithm optimizes SOA by using crossover and mutation operations in GA in order to improve the global search ability of SOA.Four algorithms,i.e.particle swarm optimization(PSO),SOA,GA and quantum-behaved particle swarm optimization(GA-QPSO)and GA-SOA are used to process the simulation and experimental data of Brillouin scattering spectrum(BSS)at different temperatures.The results show that GA-SOA improves the accuracy of extracting the center frequency shift and the minimum center frequency of Brillouin scattering spectrum compared with other three algorithms.The shift error is 0.203 MHz.Therefore,GA-SOA can be applied to the accurate extraction of BSS characteristics.

Proton Exchange Membrane Fuel Cell Modeling Based on Seeker Optimization Algorithm

Seeker optimization algorithm （SOA） has applications in continuous space of swarm intelligence. In the fields of proton exchange membrane fuel cell （PEMFC） modeling, SOA was proposed to research a set of optimized parameters in PEMFC polarization curve model. Experimental result showed that the mean square error of the optimization modeling strategy was only 6.9 × 10^-23. Hence, the optimization model could fit the experiment data with high precision.

主动遥感光谱仪在滴灌棉花上的应用

本文利用主动遥感光谱仪Green Seeker监测滴灌棉花的生长情况,从不同氮营养条件下NDVI随生育期的动态变化、各生育时期的不同氮营养NDVI值动态变化进行了全面分析。试验结果表明,不同氮营养条件下,NDVI值变化呈"低-高-低"变化趋势,在棉花出苗后100 d出现最大值,总体上高氮处理条件下NDVI值高于低氮处理的NDVI值;棉花盛铃期冠层NDVI值最大,盛蕾期最小,花期和初絮期NDVI值相差不明显。在棉花各生育,随着施氮量的增加,冠层NDVI值呈逐渐增加趋势。表明使用主动遥感光谱仪获得的NDVI值能够真实反映作物的生长状况,有利于提高棉花的田间精准管理。