Transmit Power Minimization for IRS-Assisted NOMA-UAV Networks

The flexibility of unmanned aerial vehicles(UAVs)allows them to be quickly deployed to support ground users.Intelligent reflecting surface(IRS)can reflect the incident signal and form passive beamforming to enhance the signal in the specific direction.Motivated by the promising benefits of both technologies,we consider a new scenario in this paper where a UAV uses non-orthogonal multiple access to serve multiple users with IRS.According to their distance to the UAV,the users are divided into the close users and remote users.The UAV hovers above the close users due to their higher rate requirement,while the IRS is deployed near the remote users to enhance their received power.We aim at minimizing the transmit power of UAV by jointly optimizing the beamforming of UAV and the phase shift of IRS while ensuring the decoding requirement.However,the problem is non-convex.Therefore,we decompose it into two sub-problems,including the transmit beamforming optimization and phase shift optimization,which are transformed into second-order cone programming and semidefinite programming,respectively.We propose an iterative algorithm to solve the two sub-problems alternatively.Simulation results prove the effectiveness of the proposed scheme in minimizing the transmit power of UAV.

A Survey of Digital Content Required for STD Prevention Education Taught by School Nurses

Purpose: In recent years, there has been concern in Japan about the increase in STDs among adolescents aged 15 - 19. In order to prevent STDs and guide adolescents toward desirable sexual behavior, this study’s goal was to examine the actual state of STD prevention education taught by school nurses as part of the school curriculum, as well as the kinds of digital content they wish to have for teaching on the subject. Method: An anonymous, self-administered questionnaire was distributed by email and leaflet. Targeting the 100 valid responses received from the surveyed school nurses, descriptive statistics were made for each survey item and comparisons were made between the early- and mid-career groups based on years of experience. Results: 70.0% of respondents reported teaching about STDs in Health & Physical Education classes. School nurses in the early-career group used ready-made materials, while the mid-career group used both ready-made and self-made materials. 95% of respondents reported that they had little or no knowledge of STDs, while 84% reported that they were “good” or “fairly good” at teaching classes on sexuality. Both groups reported difficulty with the topics of “phimosis” and “nocturnal emissions” in the physiological category, “sexual behavior” in the “sex-adjacent” category, and “sexual and reproductive issues” in the psychosocial category. Respondents expressed a need for digital content covering the topics of “sexual violence”, “sexual abuse”, “sexually transmitted diseases”, and “how to turn down sex”. The mid-career group desired digital content for more items than the early-career group, with significant differences in the pathogens involved in sexually transmitted diseases and sex-adjacent items. 32.0% of respondents answered that they had done self-study for sex education classes in the past three years, and both groups desired self-study on “sexually transmitted diseases”, with the mid-career group significantly higher than the early-career group on “cervical cancer & HPV”, “emergency contraceptives”, and “media literacy”. Conclusion: Health & Physical Education is the main subject that covers STDs, and pre-existing materials are commonly used. It is expected that this is due to nurses’ busy schedules and the fact that only one school nurse is assigned to each school. The data collected suggested that nurse teachers want categorized digital content that can be used in the classes they are responsible for, rather than educational content on topics they are not comfortable with. In addition, given the changing environment surrounding sex, it was clear that they wish to understand the realities and needs of the high school students they teach, and desire self-study opportunities to improve their teaching methods.

Seroprevalence Survey of HIV and Hepatitis B Virus and Behavioral Characteristics among Heavy Truck Drivers along Port Sudan-Khartoum Highways

The prevalence of human immunodeficiency virus (AIDS) and hepatitis B virus among heavy truck drivers and their assistants has been well documented globally in correlation with their behavioral characteristics. The present study aimed to screen for human immunodeficiency virus (HIV), hepatitis B virus (HBV), and behavioral characteristics among heavy truck drivers in Port Sudan. A cross-sectional study was conducted on 274 heavy truck drivers and their assistants who used the highway Port Sudan-Khartoum in Port Sudan city during 2019-2021. Data on behavioral characteristics and substance use habits were collected using a structured questionnaire, and an ELISA test was used to screen for HIV and HBV infections in the study participants. The chi-square test, odds ratio, and confidence intervals were used to find the association between behavioral characteristics and seropositive HIV/HBV. Of the 274 enrolled participants, the seroprevalence rates of HIV were 2.7% and HBV was 23.7%. Ninety-four (34.3%) of them had a history of high-risk sexual behavior outside of marriage;only two (0.7%) used condoms;14.2% of participants reported alcohol use;and 1.1% reported drug use. Univariate analysis revealed that having a sex history outside of marriage with ≥1 sex partner and never using a condom with a spouse or casual partner were significant risk factors for HIV and HBV among drivers. Fortunately, we found that most of the drivers reported low alcohol and drug use. Concerning this study, the seroprevalence of HIV and HBV is highly associated with a history of having sex outside of marriage and sexual behavior among truck drivers and assistances. Additional studies are needed to further investigate other STIs and behavioral characteristics associated with factors in truck drivers/assistance in different truck stop regions in Sudan.

Discrete Phase Shifts Control and Beam Selection in RIS-Aided MISO System via Deep Reinforcement Learning

Reconfigurable intelligent surface(RIS)for wireless networks have drawn lots of attention in both academic and industry communities.RIS can dynamically control the phases of the reflection elements to send the signal in the desired direction,thus it provides supplementary links for wireless networks.Most of prior works on RIS-aided wireless communication systems consider continuous phase shifts,but phase shifts of RIS are discrete in practical hardware.Thus we focus on the actual discrete phase shifts on RIS in this paper.Using the advanced deep reinforcement learning(DRL),we jointly optimize the transmit beamforming matrix from the discrete Fourier transform(DFT)codebook at the base station(BS)and the discrete phase shifts at the RIS to maximize the received signal-to-interference plus noise ratio(SINR).Unlike the traditional schemes usually using alternate optimization methods to solve the transmit beamforming and phase shifts,the DRL algorithm proposed in the paper can jointly design the transmit beamforming and phase shifts as the output of the DRL neural network.Numerical results indicate that the DRL proposed can dispose the complicated optimization problem with low computational complexity.

Hybrid absorbing boundary condition based on transmitting boundary and its application in 3D fractional viscoacoustic modeling

An accurate numerical simulation for wave equations is essential for understanding of wave propagation in the earth's interior as well as full waveform inversion and reverse time migration. However, due to computational cost and hardware capability limitations, numerical simulations are often performed within a finite domain. Thus, an adequate absorbing boundary condition (ABC) is indispensable for obtaining accurate numerical simulation results. In this study, we develop a hybrid ABC based on a transmitting boundary, which is referred to as THABC, to eliminate artificial boundary reflections in 3D second-order fractional viscoacoustic numerical simulations. Furthermore, we propose an adaptive weighted coefficient to reconcile the transmitting and viscoacoustic wavefields in THABC. Through several numerical examples, we determine that the proposed THABC approach is characterized by the following benefits. First, with the same number of absorbing layers, THABC exhibits a better ability in eliminating boundary reflection than traditional ABC schemes. Second, THABC is more effective in computation, since it only requires the wavefields at the current and last time steps to solve the transmitting formula within the absorbing layers. Benefiting from a simple but effective combination between the transmitting equation and the second-order wave equation, our scheme performs well in the 3D fractional Laplacian viscoacoustic numerical simulation.

Dynamic characterization of tailing dam using fully coupled dynamic analysis with different boundary conditions-a case study

The seismic response analysis of a tailing dam is studied using a fully coupled effective stress approach in conjunction with an advanced multi yield surface plastic constitutive model for tailing material.Strain controlled static and cyclic triaxial tests were carried out to obtain the constitutive model for the tailing material.The tailing materials were collected from the Rampura Agucha tailing dam(Rajasthan State,India).A 2D nonlinear finite element(FE)model was then developed using different boundary conditions from the tailing embankment constructed using the downstream and upstream method of rising using OpenSees software.In first case,the model boundary was fixed in both the X and Y directions,and in the second case,viscous dashpots were introduced for both side and horizontal boundaries.The model was validated with experimental results on tailing material.Analyses were carried out considering five different earthquake motions,which were applied at the base.Comparisons of the different boundary conditions in terms of displacement flow vectors,pore pressure and stress-strain curves during shaking are presented.From the analysis,it was observed that the viscous boundary condition replicates the actual field conditions more accurately than the fixed boundary condition.In addition,it was found that the tailing embankment constructed by the downstream and upstream method of rising is not susceptible to liquefaction and lateral spreading for earthquake motions,even for a magnitude>5.5.

Colorectal motility patterns and psychiatric traits in functional constipation and constipation-predominant irritable bowel syndrome:A study from China

BACKGROUND Functional constipation(FC)and constipation-predominant irritable bowel syndrome(IBS-C)represent a spectrum of constipation disorders.However,the majority of previous clinical investigations have focused on Western populations,with limited data originating from China.AIM To determine and compare the colorectal motility and psychiatric features of FC and IBS-C in an Eastern Chinese population.METHODS Consecutive chronic constipation patients referred to our motility clinic from December 2019 to February 2023 were enrolled.FC and IBS-C diagnoses were established using ROME IV criteria,and patients underwent high-resolution anorectal manometry(ARM)and a colonic transmit test using the Sitz marker study.Constipation-related symptoms were obtained through questionnaires.Anxiety and depression were assessed by the Hamilton anxiety rating scale and the Hamilton Depression Rating Scale-21.The clinical characteristics and colorectal motility patterns of FC and IBS-C patients were compared.RESULTS No significant differences in sex,age or abdominal discomfort symptoms were observed between IBS-C and FC patients(all P>0.05).The proportion of IBS-C patients with delayed colonic transit was higher than that of patients with FC(36.63%vs 15.91%,P<0.05),while rectosigmoid accumulation of radiopaque markers was more common in the FC group than in the IBS-C group(50%vs 26.73%,P<0.05).Diverse proportions of these dyssynergic patterns were noted within both the FC and IBS-C groups by ARM.IBS-C patients were found to have a higher prevalence of depression than FC patients(66.30%vs 42.42%,P<0.05).The scores for feelings of guilt,suicide,psychomotor agitation,diurnal variation,obsessive/compulsive disorder,hopelessness,self-abasedment and gastrointestinal symptoms were significantly higher in IBS-C patients than that in FC patients(P<0.05).For IBS-C(χ^(2)=5.438,P<0.05)but not FC,patients with normal colon transit time were significantly more likely to have anxiety than those with slow colon transit time.For IBS-C patients but not FC patients,the threshold of first constant sensation,desire to defecate and sustained urgency were all weakly correlated with the degree of anxiety(r=0.414,r=0.404,and r=0.418,respectively,P<0.05).The proportion of patients with a low threshold of desire to defecate among IBS-C patients with depression was lower than that in those without depression(69.6%vs 41.9%,χ2=4.054,P<0.05).CONCLUSION Our findings highlight both overlapping and distinctive patterns of colon transit,dyssynergic patterns,anorectal sensation,psychological distress,and associations of psychiatric and colorectal motility characteristics in FC and IBS-C patients in an Eastern Chinese population,providing valuable insights into the pathophysiological underpinnings of these disorders.

NOMA with Adaptive Transmit Power Using Intelligent Reflecting Surfaces

In this article,we use Intelligent Reflecting Surfaces(IRS)to improve the throughput of Non Orthogonal Multiple Access(NOMA)with Adaptive Transmit Power(ATP).The results are valid for Cognitive Radio Networks(CRN)where secondary source adapts its power to generate low interference at primary receiver.In all previous studies,IRS were implemented with fixed transmit power and previous results are not valid when the power of the secondary source is adaptive.In CRN,secondary nodes are allowed to transmit over the same band as primary users since they adapt their power to minimize the generated interference.Each NOMA user has a subset of dedicated reflectors.At any NOMA user,all IRS reflections have the same phase.CRN-NOMA using IRS offers 7,13,20 dB gain vs.CRN-NOMAwithout IRS for N=8,16,32 reflectors.We also evaluate the effects of primary interference.The results are valid for any number of NOMA users,Quadrature Amplitude Modulation(QAM)and Rayleigh channels.

PSO-DBNet for Peak-to-Average Power Ratio Reduction Using Deep Belief Network

Data transmission through a wireless network has faced various signal problems in the past decades.The orthogonal frequency division multiplexing(OFDM)technique is widely accepted in multiple data transfer patterns at various frequency bands.A recent wireless communication network uses OFDM in longterm evolution(LTE)and 5G,among others.The main problem faced by 5G wireless OFDM is distortion of transmission signals in the network.This transmission loss is called peak-to-average power ratio(PAPR).This wireless signal distortion can be reduced using various techniques.This study uses machine learning-based algorithm to solve the problem of PAPR in 5G wireless communication.Partial transmit sequence(PTS)helps in the fast transfer of data in wireless LTE.PTS is merged with deep belief neural network(DBNet)for the efficient processing of signals in wireless 5G networks.Result indicates that the proposed system outperforms other existing techniques.Therefore,PAPR reduction in OFDM by DBNet is optimized with the help of an evolutionary algorithm called particle swarm optimization.Hence,the specified design supports in improving the proposed PAPR reduction architecture.

Misdiagnosis of Sexually Transmitted Diseases in Hong Kong Outpatient Private Healthcare

Background and objective: Early and accurate diagnosis is one of the critical requirements for successful management of all diseases. Yet, delayed diagnosis and misdiagnosis remain as vital problems, consequently impose adverse effects on patient treatment. Sexually transmitted disease (STD) is one of the most common infectious diseases, and more than one million of STD cases are acquired every day globally. Misdiagnosis of STD inevitably exists, therefore should not be overlooked. Being a medical diagnostic laboratory providing various STDs diagnosing service in Hong Kong, we aimed to determine the misdiagnosis rate of STDs and investigate the possible underlying cause. Methods: Specimens were collected for STD diagnosis from multiple clinics during 1 June 2021 to 20 October 2021 from different clinics and hospitals were included in the study. DNA extraction was performed using magnetic bead based method;then the extracted DNA was tested using the DiagCor GenoFlowTM STD Array kit to detect the existence of any targeted pathogens. Results: 1459 specimens were collected and included during the designated time period, with 643 specimens found to be positive with at least one targeted STD pathogen. 494 of these were found to be aligned with test ordered by physicians, and the remaining 149 positive cases had at least one pathogen detected but not requested to be tested by the physicians resulting in misdiagnosis. The overall misdiagnosis rate was determined to be 23.2% (149/643), with high frequency of misdiagnosis occurred to tests ordered for one to three pathogens detection. Also, Ureaplasma urealyticum and/or Ureaplasma parvum (UU/UP) was the commonest pathogen detected in this study. Conclusion: The findings suggested incorrect test selection made by physicians was one of the major reasons of STDs misdiagnosis in outpatient settings. To reduce diagnostic errors in STD diagnosis, physicians are encouraged to select and request test that allow detection of multiple pathogens, as co-infection of multiple pathogens in STD patients is commonly observed. The correct selection of test would not only benefit the patient, but also the public health.

复杂外圆轮廓车铣复合编程

西门子数控系统提供了一种端面转换(TRANSMIT)和柱面转换(TRACYL)的方法,大大降低了车铣复合铣削的编程难度。以实例说明如何采用西门子数控系统的SinuTrain软件对复杂外圆轮廓零件进行车铣复合编程。

MIMO-OFDM系统中联合时域和空间域信号处理的改进PTS算法

为了降低多输入多输出正交频分复用(multiple input multiple output orthogonal frequency division multiplexing,MIMO-OFDM)系统中传统部分传输序列(partial transmit sequence,PTS)算法的计算复杂度,提出了联合时域和空间域信号处理的改进PTS算法。在时域信号处理部分,通过信号子块循环移位实现备选序列的增加;在空间域部分,利用天线间信号子块交换实现峰均功率比(peak to average power ratio,PAPR)抑制。同时在接收端,利用子块相位旋转引起的相位差异,本方法通过比较接收信号与星座点的距离,可以实现信号的盲检测,从而有效提高MIMO-OFDM系统的频谱利用率。仿真结果表明,提出的方法能有效地抑制MIMO-OFDM信号的PAPR,而且明显降低了传统PTS算法的计算复杂度,同时可获得跟传统PTS方法已知边带副信息时相似的比特误码率(bit error rate,BER)性能。

LTE系统中采用SGA-PTS技术降低OFDM峰均比的研究与仿真

LTE系统以OFDM技术为核心,但OFDM技术自身存在高峰均比的问题。随着硬件技术的迅速发展,概率类技术被认为是最有希望解决OFDM系统峰均比PAPR问题的一类方法。部分传输序列PTS(Partial Transmit Sequence)技术作为概率类技术中的代表技术一直广受关注,其关键问题在于搜索到合适的相位因子序列,使OFDM信号的峰均比性能最好。本文将混合的模拟退火遗传算法SGA(Simulated Annealing Genetic Algorithm)应用于PTS技术中相位因子序列的搜索,并通过仿真验证其有效性及优越性。对于相同的峰均比阈值要求,SGA算法能更好地改善PTS技术搜索最优相位因子序列的复杂度问题,使其更易于实现。

用于计算机无线局域网的微波收发信机

用于计算机无线局域网的微波收发信机陈忆元，朱晓维（东南大学毫米波国家重点实验室，南京２１００１８）目前的计算机局域网数据传输媒介仍以各种有线传输媒介为主；有线传输媒介的优点是传输可靠以及传输信息量大（如光纤），但不够方便灵活，近年来，国外很多人都致力...

西门子数控系统车铣转换功能在凸轮铣床上的改造应用

利用西门子数控系统的车铣转换功能TRANSMIT,对靠模凸轮铣床成功地进行了数控化改造,提高了机床的加工柔性,降低生产和维护成本。

不同叠加训练序列PTS降低PAPR性能比较

部分传输序列(PTS)能有效降低正交频分复用(OFDM)系统的峰均功率比(PAPR),但是其存在降低性能有限和边带信息占用频谱资源的问题。文中在传统PTS方法的基础上,基于叠加训练序列PTS降低PAPR的方法,分析了叠加不同训练序列、不同训练序列作相位旋转因子及功率分配因子对降低PAPR性能的影响。仿真结果表明:叠加自相关性较好的训练序列,降低PAPR的能力更强;不同训练序列作相位旋转因子时,对降低PAPR的效果影响不大;采用Hadama码、功率分配因子大于0.15时,降低PAPR的能力增强。该方法中的训练序列,不仅可以用于同步﹑信道估计,而且可以降低PAPR,并提高系统频谱利用率。

漫谈英语中的拉丁词

《大学英语》(复旦大学主编)精读第一册二单元课文中有这样一个单词:transatlantic(横渡大西洋的)。该词的前缀trans-源于拉丁语,有across,beyond,through的意思。相同前缀的常用词还有transform(转变),transcend(超出),translate(翻译),transmit(传送),transplant(移植),transport(运输)等等。无独有偶,在该精读第三册七单元课文中还有一个拉丁语的输入词semi-(半)

丙型肝炎研究现状

很长一段时间,对于那些确定为病毒性肝炎而通过现有技术查不到甲肝病毒、乙肝病毒指标,同时又排除了巨细胞病毒、EB病毒和疱疹病毒感染的肝炎定名为非甲非乙型肝炎(NonA,nonB,hepatitis HNANB);简言之,这是一个通过排除法而建立的一个概念含糊的诊断。1987年以来,又按实际存在的不同流行病学特征分成两大类:经肠道传播的HNANB[enterieally transmitted HNANB,HNANB(E)]和经肠道外传播的HNANB[parenterally transmitted HNANB,HNANB(P)]。然而进一步研究表明,HNANB至少由两类不同的病原体引起,在1989年9月东京召开的国际非甲非乙型肝炎及血液传染性疾病会议上。

Global epidemiology of sexually transmitted diseases

Sexually transmitted diseases （STDs） are among the first ten causes of unpleasant diseases in young adult males in developing countries and the second major cause of unpleasant diseases in young adult women. Adolescents and young adults （15-24 years old） make up only 25% of the sexually active population, but represent almost 50% of all new acquired STDs. In general, STDs are epidemics and present an enormous health and economic consequences. An adequate screening for STDs should be done on a routine basis in every part of the world. Many STDs are asymptomatic and therefore can difficult to control. The purpose of reporting of STDs is to ensure that persons who are infected will be quickly diagnosed and appropriately treated to control the spread of infection and also so that partners are notified, tested and appropriately treated. It is estimated that reported cases of STDs represent only 50%-80% of reportable STD infections in the United States, reflecting limited screening and low disease reporting. High-risk sexual behavior is a highly contributive factor of this process as it often leads to teenage pregnancies and HIV/AIDS. One possible explanation for this behavior is that people do not have enough information about the transmission of STDs or ignore the precautions required for safe sex. Approximately 60% of new HIV infections worldwide occur in young people. The frequency of high-risk behaviors among youths may also be influenced by opportunity to engage in them, particularly the amount of time that they are unsupervised by adults. However, in diagnosing and treating these patients, we can effectively prevent the spread of HIV/AIDS. Individuals infected with STDs are 5-10 times more likely than uninfected individuals to acquire or transmit HIV through sexual contact. The breaking of the genital tract lining or skin creates a portal of entry for HIV and, hence, HIV-infected individuals with other STDs are more likely to shed HIV in their genital secretions. To date, the condom is the most effective method available for males for protection against STDs. It is important to control STDs, and prevention can be the key of this process. Prevention can be achieved through education of the population, identification of symptomatic and asymptomatic people, and effective diagnosis and treatment of these patients and their partners.

Hepatitis B virus coinfection in human immunodeficiency virus-infected patients: A review

Hepatitis B virus(HBV)infection is a leading cause of chronic hepatitis,liver cirrhosis,and hepatocellular carcinoma worldwide.Due to the shared modes of transmission,coinfection with HBV and human immunodeficiency virus(HIV)is not uncommon.It is estimatedthat 10%of HIV-infected patients worldwide are coinfected with HBV.In areas where an HBV vaccination program is implemented,the HBV seroprevalence has declined significantly.In HIV/HBV-coinfected patients,HBV coinfection accelerates immunologic and clinical progression of HIV infection and increases the risk of hepatotoxicity when combination antiretroviral therapy(cART)is initiated,while HIV infection increases the risk of hepatitis events,cirrhosis,and end-stage liver disease related to chronic HBV infection.With the advances in antiviral therapy,concurrent,successful longterm suppression of HIV and HBV replication can be achieved in the cART era.To reduce the disease burden of HBV infection among HIV-infected patients,adoption of safe sex practices,avoidance of sharing needles and diluent,HBV vaccination and use of cART containing tenofovir disoproxil fumarate plus emtricitabine or lamivudine are the most effective approaches.However,due to HIV-related immunosuppression,using increased doses of HBV vaccine and novel approaches to HBV vaccination are needed to improve the immunogenicity of HBV vaccine among HIV-infected patients.