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Open Journal of Antennas and Propagation 2023年第3期11卷 49-59页

作者： Jean Ndoumbe Nelly Tchuenbou charles Hubert Kom Laboratory of energy Materials Modeling and Method (E3M) National Higher Polytechnic School of Douala University of Douala Douala Cameroon

The simulation of the electromagnetic wave propagation plays an important role in predicting the performance of wireless transmission and communication systems. This research paper performs a numerical simulation using the finite element method (FeM) to study electromagnetic propagation through both conductive and dielectric media. The simulations are made using the COMSOL Multiphysics software which notably implements the finite element method. The microwave is produced by a Vivaldi antenna at the respective frequencies of 2.6 and 5 GHz and the propagation equation is formulated from Maxwell’s equations. The results obtained show that in the air, strong electric fields are observed in the slot and the micro-strip line for the two frequencies, they are even greater when the wave propagates in the glass and very weak for the copper. The 3D evolutions of the wave in air and glass present comparable values at equal frequencies, the curves being more regular in air (dielectric). The radiation patterns produced for air and glass are directional, with a large main lobe, which is narrower at 5 GHz. For copper, the wave propagation is quite uniform in space, and the radiation patterns show two main lobes with a much larger size at 2.6 GHz than at 5 GHz. The propagation medium would therefore influence the range of values of the gain of the antenna.

关键词： Radiated Field Propagation Medium Microwave Vivaldi Antenna Finite element Method COMSOL Multiphysics

evaluation of optimization techniques in predicting optimum moisture content reduction in drying potato slices

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Artificial Intelligence in Agriculture 2020年第1期4卷 39-47页

作者： Onu Chijioke elijah K.Igbokwe Philomena T.Nwabanne Joseph O.Nwajinka charles.e.Ohale Paschal Department of Chemical engineering Nnamdi Azikiwe UniveristyP.M.B.5025 AwkaNigeria Department of Agric and Bioresource engineering Nnamdi Azikiwe UniveristyP.M.B.5025 AwkaNigeria

The use of artificial intelligence models in predicting the moisture content reduction in the drying of potato(Ipomoea batata)sliceswas the focus of *** models used were adaptive neuro fuzzy inference systems(ANFIS),artificial neural network(ANN)and response surface methodology(RSM).The parameters considered were drying time,drying air speed and *** capability and sensitivity analysis of the three models were evaluated using the correlation coefficient(R2)and some statistical error functions such as the average relative error(ARe),root mean square error(RMSe),Hybrid Fractional error Function(HYBRID)and absolute average relative error(AARe).The result showed that the three models demonstrated significant predictive behaviourwith R2 of 0.998,0.997 and 0.998 for ANFIS,ANN and *** calculated error functions of ARe(RSM=1.778,ANFIS=1.665 and ANN=4.282)and RMSe(RSM=0.0273,ANFIS=0.0282 and ANN=0.1178)suggested good harmony between the experimental and predicted *** was concluded that though the three models gave adequate predictions that were in good agreement with the experimental data,the RSM and ANFIS gave better model prediction than ANN.

关键词： Moisture content Potato Adaptive neuro fuzzy inference systems Artificial neural network Response surface methodology

Comparison of near-infrared spectroscopy and DeM simulations for tracing spatial dispersion of water during mixing

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Particuology 2018年第3期16卷 94-102页

作者： Roland Hohl Nicolas Heigl Daniel Koller charles A. Radeke Research Center Pharmaceutical engineering GmbH lnffeldgasse 13 8010 Graz Austria

The aim of this work was to validate a wet mixing process, in which a liquid spray is used to impregnate particles during mixing. The experimental results obtained using a bladed-mixer with a near-infrared sensor were compared with the results obtained using a 1 ： 1 discrete element method simulation. The porous particles used in both cases absorbed the sprayed liquid for a process time of about 18 min. Mul- tiple sensors attached to the mixer wall continuously monitored the liquid contents of passing particles. The sensors were modeled in the simulation and the resulting signals were analyzed and compared with the experimental results. We show that the algorithms used for spray and liquid absorption can be used to predict the moisture distribution inside granular materials in chemical and pharmaceutical processes. Such simulations can help to save money, e.g., in resource-intensive experimental plans and equipment design studies, and by varying material parameters.

关键词： Mixing DeM Spray Near-infrared Particles

Ultra-broadband and polarization-independent planar absorber based on multilayered graphene

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Chinese Physics B 2017年第11期26卷 186-192页

作者：王娇高超宁姜彦南 charles Nwakanma Akwuruoha Guangxi Key Laboratory of Wireless Wideband Communication and Signal Processing Key Laboratory of Cognitive Radio and Information Processing (Ministry of education) Guilin University of Electronic Technology School of electrical and electronic engineering University of Manchester

We propose an ultra-broadband and polarization independent planar absorber comprising multilayered graphene. The bandwidth of the proposed absorber is extended by increasing the number of layers of graphene, and it is polarization independent due to its symmetrical unit structure. The full wave simulation results show that an absorber with three graphenebased layers can efficiently harvest an electromagnetic wave with random polarization from 17.9 GHz to 188.7 GHz（i.e.,covering frequency regimes from K to D bands and relative bandwidth of - 165%）. The physical absorption mechanism of ultra-broadband absorption has been elaborated upon using the destructive interference method and multiple resonances approach in a multilayered medium. The proposed absorber can be used in many applications such as medical treatment,electromagnetic compatibility, and stealth technique.

关键词： multilayered graphene absorber ultra-broadband polarization independent

Mental health status in veterans residing in rural versus non-rural areas: results from the veterans’ health study

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Military Medical Research 2021年第1期8卷 79-89页

作者： Joseph J.Boscarino charles R.Figley Richard e.Adams Thomas G.Urosevich H.Lester Kirchner Joseph A.Boscarino Clinical Psychology Department William James CollegeNewtonMA 02459USA School of Social Work Tulane UniversityNew OrleansLA 70112USA Department of Sociology Kent State UniversityKentOH 44242USA Ophthalmology Service Geisinger ClinicMount PoconoPA 18344USA Department of Population Health Sciences Geisinger Clinic100 N.Academy Avenue44-00DanvillePA 17822USA

Background: The majority of Veterans Affair(VA) hospitals are in urban areas. We examined whether veterans residing in rural areas have lower mental health service use and poorer mental health ***: Veterans with at least 1 warzone deployment in central and northeastern Pennsylvania were randomly selected for an interview. Mental health status, including posttraumatic stress disorder(PTSD), major depression, alcohol abuse and mental health global severity, were assessed using structured interviews. Psychiatric service use was based on self-reported utilization in the past 12 months. Results were compared between veterans residing in rural and non-rural areas. Data were also analyzed using multivariate logistic regression to minimize the influence by confounding ***: A total of 1730 subjects(55% of the eligible veterans) responded to the survey and 1692 of them had complete geocode information. Those that did not have this information(n=38), were excluded from some analyses. Veterans residing in rural areas were older, more often of the white race, married, and experienced fewer stressful events. In comparison to those residing in non-rural areas, veterans residing in rural areas had lower global mental health severity scores;they also had fewer mental health visits. In multivariate logistic regression, rural residence was associated with lower service use, but not with PTSD, major depression, alcohol abuse, and global mental health severity score after adjusting confounding factors(e.g., age, gender, marital status and education).Conclusions: Rural residence is associated with lower mental health service use, but not with poor mental health in veterans with former warzone deployment, suggesting rural residence is possibly protective.

关键词： Veterans Rural Risk factors PTSD Alcohol abuse Depression Service use Census data

基于离散元的砂土在不同应力路径和剪切模式下的强度和临界状态行为

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Journal of Central South University 2023年第6期30卷 1964-1980页

作者：朱旻奕龚国斌张雪夏骏 MOY charles-K.S. WILKINSON Stephen Department of Civil engineering Design SchoolXi’an Jiaotong-liverpool UniversitySuzhou 215123China Department of Civil engineering and Industrial Design University of LiverpoolLiverpool L693BXUnited Kingdom engineering and Information Sciences University of Wollongong in DubaiDubai 20183United Arab Emirates

本文通过离散元模拟的方法研究了砂土在不同轴对称应力路径和剪切模式下的强度和临界状态行为。其中,应力路径包括轴向压缩和轴向拉伸,而剪切模式包括常规三轴和恒定平均应力三轴。试样分为松砂和密砂两种,初始围压范围控制在100~900 kP... 详细信息

本文通过离散元模拟的方法研究了砂土在不同轴对称应力路径和剪切模式下的强度和临界状态行为。其中,应力路径包括轴向压缩和轴向拉伸,而剪切模式包括常规三轴和恒定平均应力三轴。试样分为松砂和密砂两种,初始围压范围控制在100~900 kPa。当轴向应变(绝对值)接近45%时,所有样品均达到临界状态。模拟结果表明在相同围压下,偏应力的临界状态值是唯一的,与初始密度无关,但与应力路径有关:临界状态下轴向压缩的偏应力通常大于轴向拉伸的偏应力。应力比在临界状态下的值与剪切模式和围压均无关,但取决于应力路径。在围压一定的条件下,摩擦角在临界状态下具有唯一性,且不受剪切模式、应力路径和初始密度的影响,这表明Mohr-Coulomb准则(在轴对称条件下等效于Matsuoka准则)是有效的临界状态强度准则。在围压和剪切方式一定的条件下,孔隙率在临界状态下的值与初始密度无关。在临界状态下,不同试样机械配位数的差异是由平均应力的变化所引起的。

关键词：离散元轴对称应力路径剪切模式砂土临界状态破坏准则

Transcriptional Regulation of the Ambient Temperature Response by H2A.Z Nucleosomes and HSF1 Transcription Factors in Arabidopsis

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Molecular Plant 2017年第10期10卷 1258-1273页

作者： Sandra Cortijo Varodom Charoensawan Anna Brestovitsky Ruth Buning charles Ravarani Daniela Rhodes John van Noort Katja e. Jaeger Philip A. Wigge The Sainsbury Laboratory University of Cambridge 47 Bateman Street Cambridge CB2 1LR UK Department of Biochemistry Faculty of Science Mahidol University 272 Rama Vl Road Ratchathewi District Bangkok 10400 Thailand Integrative Computational BioScience (ICBS) Center Mahidor University 999 Phuttamonthon 4 Road Salaya Nakhon Pathom 73170 Thailand Biological and Soft Matter Physics Huygens-Kamerlingh Onnes Laboratory Leiden University Niels Bohrweg 2 2333 CA Leiden the Netherlands Medical Research Council Laboratory for Molecular Biology Francis Crick Avenue Cambridge CB2 0QH UK Institute of Structural Biology Nanyang Technical University 50 Nanyang Avenue Singapore 639798 Singapore

Temperature influences the distribution, range, and phenology of plants. The key transcriptional activators of heat shock response in eukaryotes, the heat shock factors （HSFs）, have undergone large-scale gene amplification in plants. While HSFs are central in heat stress responses, their role in the response to ambient temperature changes is less well understood. We show here that the warm ambient temperature transcriptome is dependent upon the HSFA1 clade ofArabidopsis HSFs, which cause a rapid and dynamic eviction of H2A.Z nucleosomes at target genes. A transcriptional cascade results in the activation of multiple downstream stress-responsive transcription factors, triggering large-scale changes to the transcriptome in response to elevated temperature. H2A.Z nucleosomes are enriched at temperature-responsive genes at non-inducible temperature, and thus likely confer inducibility of gene expression and higher responsive dynamics. We propose that the antagonistic effects of H2A.Z and HSF1 provide a mechanism to activate gene expression rapidly and precisely in response to temperature, while preventing leaky transcription in the absence of an activation signal.

关键词： gene expression regulation plant temperature sensing and signaling transcriptomics nucleosome dynamics histone variant H2A.Z heat shock transcription factors

ectopic expression of neurotrophic peptide derived from saposin C increases proliferation and upregulates androgen receptor expression and transcriptional activity in human prostate cancer cells

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Asian Journal of Andrology 2007年第5期9卷 601-609页

作者： Yan Ding Hui-Qing Yuan Feng Kong Xiao-Yan Hu Kai Ren Jie Cai Xiao-Ling Wang charles Y. e Young Department of Biochemistry and Molecular Biology School of Medicine Shandong University Jinan 250012 China Departments of Urology and Biochemistry and Molecular Biology Mayo Graduate School Mayo Clinic Rochester MN55905 USA

Aim： To determine the effects of the functional domain of saposin C （neurotrophic peptide [NP]） on androgen receptor （AR） expression and transcriptional activity. Methods： We constructed DNA vectors expressing NP or a chimeric peptide of the viral TAT transduction domain and NP （TAT-NP） using gene cloning technology. The effects of ectopic expression of NP or TAT-NP on cell growth were examined by 3-（4, 5-dimethylthiazol-2-yl）-2, 5-diphenyl-2H-tetrazolium bromide （MTT） assay. Reverse transcription-polymerase chain reaction （RT-PCR）, Western blot, transient transfection and reporter gene assays were used to determine the effects of NP on AR expression and activation. Results： NP stimulated proliferation of androgen responsive LNCaP cells in the absence of androgens. RT-PCR and Western blot analyses showed that ectopic expression of NP resulted in induction of AR gene expression, and that the NP-stimulated expression of AR could be synergistically enhanced in the presence of androgens. Furthermore, reporter gene assay results showed that NP could enhance AR transactivation by increasing androgen-inducible gene reporter activity. Conclusion： We provided evidence that ectopic expression of saposin C-originated NP could upregulate AR gene expression and activate the AR transcriptional function in an androgen-independent manner in prostate cancer cells.

关键词： neurotrophic peptide, androgen receptor saposin C prostate carcinoma cell lines

Review of the United States Refractories Industry

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China's Refractories 2003年第1期12卷 1-5页

作者： charles.e.Semler Semler Materials Services PhoenixArizona 85248USA

Factors affecting the U.S. refractories industry, such as decreasing demand, mergers , and decreased education are discussed, along with manufacturing statistics (i. e. , annual value and product trends ) , indicating that the U.S. market has declined for five straight years. Research activities have changed, with more emphasis on practical, applied projects , which have continued to produce important advances. Many challenges and opportunities remain, based on the current and future business requirements .

关键词： Refractories situation the United States

Commentary on a novel technique for distal hypospadias repair using forked corpus spongiosum

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Asian Journal of Andrology 2021年第1期23卷 122-122页

作者： Hannah Kay e charles Osterberg Dell Medical School University of Texas at Austin1601 Trinity StreetSuite 704AustinTX 78704USA

First-line treatment for hypospadias is surgical repair between 6 and 18 months of *** of treatment may include improved urinary stream,a cosmetically pleasing appearance,and reduction of penile curvature(chordee).1 G... 详细信息

关键词： urinary treatment curvature