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.

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.

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.

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.

Partial transmitting sequence method based on trellis factor search

To obtain good trade-offs between complexity and performance onpeak-to-average power ratio (PAPR) reduction in orthogonal frequency division multiplexing (OFDM)using partial transmitting sequence (PTS) schemes, a trellis structure based PTS factor searchmethod is proposed. The trellis search is with a variant constraint length L_C, 1 ≤ L_C ≤ V-1,where V is the number of PTS subblocks. The method is to decide a PTS factor by searching all thepossible paths obtained by varying L_C consecutive factors. The trellis search can be viewed as ageneral PTS factor search model. If L_C = V-1, it is a full search, and if L_C = 1, it is aniterative search. Using different constraint lengths, trellis factor search PTS exhibits differentPAPR reduction performances. A larger L_C results in a better performance and L_C = V-1 results inthe optimum. However, a larger L_C requires more computation. This helps to choose a good trade-offbetween complexity and performance.

FINITE ELEMENT-ARTIFICIAL TRANSMITTING BOUNDARY METHOD FOR WAVE SCATTERING FROM IRREGULAR CYLINDER

The finite element artificial transmitting boundary method is employed here to treat the near field scattering of a cylindrical wave from an irregular cylinder. A comparison is made between this method and the analytical one. And then examples are given to demonstrate the solution of several problems of the irregular object scattering. The method can not only produce clear physical pictures, but can efficiently handle many complicated scattering problems.

Socio-Demographic, Clinical, and Hygiene Profile of Syndromically Managed Sexually Transmitted Diseases: A Cross Sectional Study in a Tertiary Care Center in India

Background: Sexually transmitted diseases are one of the several major public health concerns, the burden of which is borne by low- and middle-income countries like India. Purpose: The purpose is to evaluate the relationship between menstrual and sanitary hygiene and sexually transmitted diseases (STD) based on syndromic diagnosis Methods: An out-patient department (OPD) based cross sectional survey to determine these associations, if any exist, which would help critically analyze syndromic management. STD was reported by the presence of vaginal/cervical/urethral discharge with or without irritation and itching, lower abdominal pain and ulcer. Results: The prevalence of STD was 66.84% with the most commonly reported symptoms being discharged (31.18%), followed by abdominal pain (17.92%) and itching/irritation (12.90%), with ulcer (4.83%) being the least reported symptom. Perimenopausal age ((AOR: 0.420 [CI: 0.189 - 0.915];p = 0.030), higher grades of education ((AOR: 0.228 [CI: 0.119 - 0.424];p < 0.001) for secondary), urban residency (AOR: 0.435 [CI: 0.686 - 2.733];p < 0.001), and contraception use (AOR: 0.531 [CI: 0.308 - 0.887];p = 0.018) were associated with lesser odds of presenting with an STD symptom. Belonging to a minority religious community (AOR: 7.20 [CI: 1.866 - 48.251];p < 0.012) or backward castes (AOR: 3.753 [CI: 1.587 - 10.144];p < 0.001), having similar illness (AOR: 4.205 [CI: 2.795 - 6.439];p < 0.001) or having an invasive gynecological procedure done in the past one year (AOR: 1.953 [CI: 1.184 - 3.295];p = 0.010) and washing the reusable sanitary material only with water (AOR: 4.900 [CI: 2.701 - 9.116];p < 0.001) as compared to washing it with water and soap, had a higher association with presenting with STD symptoms. Stratified analysis also showed that women presenting discharge (AOR: 2.049 [CI: 1.343 - 3.146] for vaginal and cervical;AOR: 1.426 [CI: 0.826 - 2.482] for urethral) were more likely to not have a toilet facility in an accessible condition. Women with sanitary napkin use had lesser odds (AOR: 0.780 [CI: 0.516 - 1.180];p = 0.293) of presentation for STD in OPD than women who used other material. Conclusion: To better manage the group of diseases that may present with symptoms of STD under syndromic approach, we propose interventions such as menstrual hygiene education and promotion of the use of sanitary napkins among women especially those belonging to lower socio-economic sections of the society.

Epidemiological Analysis of Sexually Transmitted Disease Control and Prevention from 1998 to 2003 in Chongqing

Objectives： To understand trends and epidemiology of STDs in Chongqing from 1998 to 2003 and to provide scientific evidence for developing preventive strategies and distributing government health resources effectively. Methods： STD case-reporting data collected from 43 counties and districts in Chongqing from 1998 to 2003 were analyzed with STD Data Management Software and Excel Software. Results： A total of 133,323 cases of eight different STDs were reported from 1998-2003. The annual incidence of all eight STDs combined was 71.89/10^5.Generally, reported cases and incidence have decreased since 2001. Although gonorrhoea diagnoses made up a significant proportion of the STD burden, this proportion decreased annually. The proportion of the STD burden attributed to Condyloma accuminatum （CA） was always above 30 percent. The proportions of non-gonoccocal urethritis, genital herpes and syphilis within the combinedSTD burden increased gradually from 1998 to 2003.Reported cases of HIV increased rapidly over this time. A total of 214 HIV cases were reported from 1998 to 2003,the majority of which were among men. For HIV, the maleto-female ratio was 1.17, but CA was found among more women than men. Incidence for all STDs was highest among 20-39 year olds, who accounted for 72.2% of reported infections. The majority of STDs were transmitted through extra-marital intercourse,accounting for 55.3%. Conclusion： The STD epidemic in Chongqing changed from 1998-2003. STD incidence declined, as a result of various factors. The epidemiology of STDs has changed.HIV incidence has increased rapidly. This indicates that the AIDS epidemic has reached a critical period. The results of this study suggest a need for readjusting control measures and redistributing health resources.

Digital core based transmitted ultrasonic wave simulation and velocity accuracy analysis

Transmitted ultrasonic wave simulation （TUWS） in a digital core is one of the important elements of digital rock physics and is used to study wave propagation in porous cores and calculate equivalent velocity. When simulating wave propagates in a 3D digital core, two additional layers are attached to its two surfaces vertical to the wave-direction and one planar wave source and two receiver-arrays are properly installed. After source excitation, the two receivers then record incident and transmitted waves of the digital rock. Wave propagating velocity, which is the velocity of the digital core, is computed by the picked peak-time difference between the two recorded waves. To evaluate the accuracy of TUWS, a digital core is fully saturated with gas, oil, and water to calculate the corresponding velocities. The velocities increase with decreasing wave frequencies in the simulation frequency band, and this is considered to be the result of scattering. When the pore fluids are varied from gas to oil and finally to water, the velocity-variation characteristics between the different frequencies are similar, thereby approximately following the variation law of velocities obtained from linear elastic statics simulation （LESS）, although their absolute values are different. However, LESS has been widely used. The results of this paper show that the transmission ultrasonic simulation has high relative precision.

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.

The prevalence of transfusion transmitted virus infection in blood donors

INIRODUCIIONA newly discovered DNA virus,transfusiontransmitted virus (TTV),was reported as a cause ofpost-transfusion hepatitis of unknown etiology inJapan.In order to investigate TTV prevalence insouthern China,a study was carried out amongblood donors,patients with liver diseases andhemodialysis to determine the epidemiologicalcharateristics.

Transmitted and Reflected Coefficients for Horizontal or Vertical Plate Type Breakwater

Surface or submerged horizontal or vertical plate can be considered as a new concept breakwater. This paper investigates the wave-plate interaction of this type of breakwater by use of the boundary element method. The relationships of wave transmitted and reflected among plate thickness, submergence and length are carefully studied by numerical simulation. It is shown that： （1） The transmitted coefficients of submerged horizontal plate or vertical plate will become larger with the increase of plate thickness and reduce rapidly with the decrease of plate submergence. （2） Both surface horizontal and vertical plate are efficient for intermediate and short wave elimination, but vertical plate is more effective. （3） Submerged horizontal plate can act more effectively than submerged vertical plate does. With all wave frequencies, the vertical plate almost has no wave elimination effect.

Dynamic analysis of a sexually transmitted disease model on complex networks

In this paper,a sexually transmitted disease model is proposed on complex networks,where contacts between humans are treated as a scale-free social network.There are three groups in our model,which are dangerous male,non-dangerous male,and female.By mathematical analysis,we obtain the basic reproduction number for the existence of endemic equilibrium and study the effects of various immunization schemes about different groups.Furthermore,numerical simulations are undertaken to verify more conclusions.

Performance Evaluation of Space-Time Spreading and Orthogonal Transmit Diversity

Space-time spreading (STS) and orthogonal transmit diversity (OTD) are towtransmit diversity schemes proposed by cdma2000 standard. In this paper, performance comparisonanalysis of the two transmits diversity schemes in multipath channel under multiuser situation arecarried out. Link level simulation in forward link cdma2000 is performed in IMT-2000 channel.Performance analysis and simulation results show that the performance improvement provided STS overOTD decreases as the increase of propagation path number and decrease of the user number.

Donor transmitted and de novo cancer after liver transplantation

Cancers in solid organ recipients may be classified as donor transmitted,donor derived,de novo or recurrent.The risk of donor-transmitted cancer is very low and can be reduced by careful screening of the donor but cannot be abolished and,in the United Kingdom series is less than 0.03%.For donors with a known history of cancer,the risks will depend on the nature of the cancer,the interventions given and the interval between diagnosis and organ donation.The risks of cancer transmission must be balanced against the risks of death awaiting a new graft and strict adherence to current guidelines may result increased patient death.Organs from selected patients,even with high-grade central nervous system(CNS)malignancy and after a shunt,can,in some circumstances,be considered.Of potential donors with non-CNS cancers,whether organs may be safely used again depends on the nature of the cancer,the treatment and interval.Data are scarce about the most appropriate treatment when donor transmitted cancer is diagnosed:sometimes substitution of agents and reduction of the immunosuppressive load may be adequate and the impact of graft removal should be considered but not always indicated.Liver al-lograft recipients are at increased risk of some de novo cancers,especially those grafted for alcohol-related liver disease and hepatitis C virus infection.The risk of lymphoproliferative disease and cancers of the skin,upper airway and bowel are increased but not breast.Recipients should be advised to avoid risk behavior and monitored appropriately.

Performance Comparison of Space-Time Trellis Codes and Space-Time Transmit Diversity under the Same Bandwidth Efficiency

Space time coding can provide high data rate and performance gain for wireless communication system. Performance comparison of space time trellis codes and space time transmit diversity is carried out under the same bandwidth efficiency in this paper. We also propose some optimum low rate space time trellis codes in quasi static Rayleigh fading chan￣nel. Performance analysis and simulation show that the low rate space time trellis codes outperform space time transmit diversity at the same bandwidth efficiency, and are more suitable for the power limited wireless communication system which has no strict requirement on bandwidth efficiency.

Time-Domain Full Waveform Inversion Using the Gradient Preconditioning Based on Transmitted Wave Energy

The gradient preconditioning approach based on seismic wave energy can effectively avoid the huge memory consumption of the gradient preconditioning algorithms based on the Hessian matrix. However, the accuracy of this approach is prone to be influ- enced by the energy of reflected waves. To tackle this problem, the paper proposes a new gradient preconditioning method based on the energy of transmitted waves. The approach scales the gradient through a precondition factor, which is calculated by the ‘ap- proximate transmission wavefield’ simulation based on the nonreflecting acoustic wave equation. The method requires no computing nor storing of the Hessian matrix and its inverse matrix. Furthermore, the proposed method can effectively eliminate the effects of geometric spreading and disproportionality in the gradient illumination. The results of model experiments show that the time-domain full waveform inversion (FWI) using the gradient preconditioning based on transmitted wave energy can achieve higher inversion accuracy for deep high-velocity bodies and their underlying strata in comparison with the one using the gradient preconditioning based on seismic wave energy. The field marine seismic data test shows that our proposed method is also highly applicable to the FWI of field marine seismic data.

Distributed Transmit Beamforming for UAV to Base Communications

Distributed transmit beamforming(DTB) is very efficient for extending the communication distance between a swarm of UAVs and the base,particularly when considering the constraints in weight and battery life for payloads on UAVs.In this paper,we review major function modules and potential solutions in realizing DTB in UAV systems,such as timing and carrier synchronization,phase drift tracking and compensation,and beamforming vector generation and updating.We then focus on beamforming vector generation and updating,and introduce a concatenated training scheme,together with a recursive channel estimation and updating algorithm.We also propose three approaches for tracking the variation of channels and updating the vectors.The effectiveness of these approaches is validated by simulation results.

Current Status of Soil-transmitted Nematode Infection in China

Objective To carry out national surveys for ascertaining the current status and trends of soil-transmitted nematode infections in China, providing scientific basis for further developing control strategies. Methods In 1988-1992 （hereinafter abbreriated as ＂survey in 1990＂）, a stratified cluster random sampling method was used in the survey. In 2001-2004 （hereinafter abbreriated as ＂survey in 2003＂）, in order to compare with the survey in 1990, two-characteristic stratified cluster random sampling method was used and 687 investigation spots were sampled from the 2848 spots selected in the survey in 1990. Kato-Katz thick smear method was used to examine the eggs of soil-transmitted nematodes in fecal samples. Results The prevalence rates were 53.6% and 19.6% for soil-transmitted nematodes, 14.6% and 6.120% for hookworms, 44.6% and 12.7% for Ascaris lumbricoides, 17.4% and 4.630% for Trichuris trichiura in survey 1990 and survey 2003, respectively. The prevalence rates of soil-transmitted nematodes were higher in 13 provinces than the average level in China in the survey in 1990, and higher in 8 provinces than the average level in the survey in 2003. The prevalence of hookworms, Ascaris lumbricoides, Trichuris trichiura and the overall prevalence of soil-transmitted nematodes were higher in females than in males. It is estimated from the results of survey in 2003 that the number of persons with soil-transmitted nematode infections in the country is about 129 million, less than that in the survey in 1990. Conclusion The prevalence of soil-transmitted nematodes has declined considerably but is still relatively high in some provinces and autonomous regions. Control activities and socioeconomic development may have contributed to the decreased prevalence.

Performance Analysis of Uplink Massive Spatial Modulation MIMO Systems in Transmit-Correlated Rayleigh Channels

In this paper,the performance of uplink multiuser massive multiple-input multipleoutput(MIMO)system with spatial modulation over transmit-correlated Rayleigh fading channel is investigated,where a large number of antennas are deployed at the base station and linear zero-forcing(ZF)receiver is employed for detection.By taking the transmit correlation and the randomness of shadow fading in to account,the bit error rate(BER)performance of the system is analyzed.According to the performance analysis,an approximated expression of overall average BER of the system is attained.Besides,asymptotic performance is studied and the corresponding BER expression at high signal-to-noise ratio is derived.On this basis,the diversity gain of the system can be obtained for performance evaluation.Simulation results show that the derived theoretical expressions match the simulated values well,which verifies the correctness of our analysis.