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Operational feasibility study of stagnation pressure reaction control for a mid-caliber non-spinning projectile

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Defence Technology（防务技术） 2023年第6期24卷 109-121页

作者： f.Bouquet The Netherlands Organisation for Applied Scientific Research Oude Waalsdorperweg 632597 AK Den Haagthe Netherlands

Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering *** Netherlands Organisation for Applied Scientific Research has developed a fin-less control technology called Stagnation Pressure Reaction Control(SPRC)that takes stagnation pressure air and directs it sideways to control non-spinning *** a previous study,this technology was demonstrated at Mach 2 wind-tunnel conditions to achieve up to 1.5°controllable angle of incidence for a non-spinning,aerodynamically unstable projectile-like test *** an operational scenario,the decelerating projectile will experience a decline in control force while the simultaneous forward shift of the center of pressure increases the need for control ***,angles of incidence exceeding 1.5°will be experienced under realistic flight conditions,especially against maneuvering *** work addresses these challenges and presents an operational feasibility study for a practical application of SPRC in a non-spinning mid-caliber gun-launched projectile,using experiment data on control latency and force of the earlier *** illustrates the combined effect of the control-and stability dynamics and underlines the potential of an SPRC projectile as a precisionoperation *** research revealed that SPRC technology can stabilize and control the hypothesized projectile in a direct fire scenario against stationary and maneuvering targets.

关键词： Supersonic projectile feasibility study Ram air Stagnation pressure reaction control Simulation Attitude control

Radiation force and torque on a two-dimensional circular cross-section of a non-viscous eccentric layered compressible cylinder in acoustical standing waves

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Chinese Physics B 2021年第2期30卷 355-366页

作者： f G Mitri Santa fe NM 87508USA

The purpose of this study is to develop an analytical formalism and derive series expansions for the time-averaged force and torque exerted on a compound coated compressible liquid-like cylinder,insonified by acoustic standing waves having an arbitrary angle of incidence in the polar(transverse)*** host medium of wave propagation and the eccentric liquid-like cylinder are *** computations illustrate the theoretical analysis with particular emphases on the eccentricity of the cylinder,the angle of incidence and the dimensionless size parameters of the inner and coating cylindrical fluid *** method to derive the acoustical scattering,and radiation force and torque components conjointly uses modal matching with the addition theorem,which adequately account for the multiple wave interaction effects between the layer and core fluid *** results demonstrate that longitudinal and lateral radiation force components ***,an axial radiation torque component is quantified and computed for the non-absorptive compound cylinder,arising from geometrical asymmetry considerations as the eccentricity *** computational results reveal the emergence of neutral,positive,and negative radiation force and torque depending on the size parameter of the cylinder,the eccentricity,and the angle of incidence of the insonifying ***,based on the law of energy conservation applied to scattering,numerical verification is accomplished by computing the extinction/scattering energy *** results may find some related applications in fluid dynamics,particle trapping,mixing and manipulation using acoustical standing waves.

关键词： radiation force radiation torque liquid compound cylinder multiple scattering acoustical standing waves

Evolutionary model of brain tumor circulating cells: Cellular galaxy

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World Journal of Clinical Oncology 2021年第1期12卷 13-30页

作者： parvin Mehdipour firoozeh Javan Morteza faghih Jouibari Mehdi Khaleghi Masoud Mehrazin Department of Medical Genetics Tehran University of Medical SciencesSchool of MedicineTehran ***TehranIran Department of Neurosurgery Shariati University HospitalTehran ***TehranIran Shariati Hospital Tehran University of Medical SciencesTehran ***TehranIran Tehran University of Medical Science Tehran ***TehranIran

BACKGROUND Although circulating tumor cells(CTCs)have been the focus of consideration for a decade,a categorized cell-based diagnostic strategy is *** personalized management and complementary/analytical-strategy of data require an alphabetic ***,we aimed to determine the behavior of CTCs in tumor and blood in order to provide the hypothetical-based agenda in the brain *** the protein expression(PE)using a single cell-based method would clarify the heterogeneity and diversity in tumor and blood,which are key events in the evolution in brain *** fact,heterogeneity,diversity,and evolution are required for cancer initiation and *** To explore CTCs in brain tumors and blood cells and to assay intensity of PE through personalized *** The focal population included 14 patients with meningioma,and four patients with metastatic brain tumors(T).PE was assayed by immunofluorescence in tumors cells and CTCs in 18 patients with brain *** test was applied between the T cells and CTCs in tumor tissue and in vascular system.T/CTC ratio-based classification of PE in macrophage chemoattractant chemokine ligand 2(CCL2),vascular endothelial growth factor(VEGf),epidermal growth factor(EGf),CD133,cyclin E,neurofilament marker,cytokeratin 19,and leukocyte common antigen(CD45)were *** Total analyzed cells ranged between 10794-92283 for tumor cells and between 117-2870 for *** of histopathologic and status of an ataxiatelangiectasia mutated polymorphism(D1853N)in 18 patients affected with brain tumors were also *** course of evolution and metastatic event relied on the elevated protein expression in CTCs,which could be considered as a prognostic *** protein expression of the migrated cells into the blood stream and the tumor was indicative of the occurrence of ***,the harmonic co-expression between CCL2/EGf and CCL2/VEGf could facilitate the tumor

关键词： Circulating tumor cells Brain tumor Protein expression Personalized Somatic/circulating tumor cell evolution Metastasis

The Recurrence of Natural Disasters in Jowhar, Middle Shabelle Region, Somalia: The Causes and Impacts

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Journal of Environmental Protection 2022年第9期13卷 657-670页

作者： Mohamed Ali Ahmed Mohamed Hassan Mohamed Mst. Mahmuda parvin Predrag Ilić Department of Environmental Science Stamford University Bangladesh Dhaka Bangladesh Department of Public and Environmental Health Somali International University Mogadishu Somali PSRI Institute for Protection and Ecology of the Republic of Srpska Banja Luka Bosnia and Herzegovina

Natural disasters usually involve a phenomenon with consequences that exceed the response capabilities of local communities and have a significant impact on the region’s socioeconomic development. Droughts, floods, and hurricanes are all natural disasters that jeopardize the environment and the lives of Somalis. Severe floods have devastated the south and central parts of the country multiple times, destroying infrastructure and homes and killing many vulnerable people. Droughts in the south and central parts of the country, particularly in the Middle Shebelle region, have killed a number of children and mothers. It also had a negative influence on crops and cattle. Objective of this study is to know the recurrence of Natural Disasters in Jowhar, Middle Shabelle region, Somalia: The Causes and Impacts. The Somali people are completely aware of natural disasters such as droughts and floods, and they are self-sufficient in dealing with the consequences of these disasters. furthermore, the Somali government has not fully created environmental laws to protect and conserve the environment, and the majority of laws, rules, acts, and regulations are not used or administered effectively. We also found that the Somali government is not yet financially prepared to deal with these crises, and that there are no strategic plans in the central government or even state administrations to prevent or at least control these disasters from causing extreme harm to the community and the environment.

关键词： Natural Disasters floods and Droughts Causes Impacts of the Environment

Investigation on the influence of the initial RDX crystal size on the performance of shaped charge warheads

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Defence Technology（防务技术） 2019年第5期15卷 802-807页

作者： f.Majiet f.J.Mostert Rheinmetall Denel Munition Somerset WestSouth Africa Centre for Scientific&Industrial Research PretoriaSouth Africa

Copper lined wave shaped shaped charges of particular design and liner metallurgy were used to investigate the effect of explosive crystal size on the resultant shaped charge jet *** A3 with RDX of three different average crystal sizes,i.e.30μm,100μm and 300μm were used in the *** other parameters in the charge were kept constant and in particular,care was given to obtain consistent dimensional quality and liner microstructure,in order to prohibit the variation of other *** flash-X-ray diagnostics were used in field tests to obtain the jet parameters from multiple firings of similar *** is found that the varying crystal size of the RDX has a marginal influence in the total jet length of the ***,it is also found that there is less variation between firings in the jet parameters for jets from the charges loaded with the crystal size of 100 μm.

关键词： shaped size crystal

frame Length Dependency for fundamental frequency Extraction in Noisy Speech

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Journal of Signal and Information Processing 2024年第1期15卷 1-17页

作者： Md. Saifur Rahman Any Chowdury Nargis parvin Arpita Saha Moinur Rahman Department of Information and Communication Technology Comilla University Cumilla Bangladesh Department of Computer Science and Engineering Bangladesh Army International University of Science and Technology (BAIUST) Cumilla Bangladesh Department of Information Technology University of Information Technology and Sciences (UITS) Dhaka Bangladesh

The fundamental frequency plays a significant part in understanding and perceiving the pitch of a sound. The pitch is a fundamental attribute employed in numerous speech-related works. for fundamental frequency extraction, several algorithms have been developed which one to use relies on the signal’s characteristics and the surrounding noise. Thus, the algorithm’s noise resistance becomes more critical than ever for precise fundamental frequency estimation. Nonetheless, numerous state-of-the-art algorithms face struggles in achieving satisfying outcomes when confronted with speech recordings that are noisy with low signal-to-noise ratio (SNR) values. Also, most of the recent techniques utilize different frame lengths for pitch extraction. from this point of view, This research considers different frame lengths on male and female speech signals for fundamental frequency extraction. Also, analyze the frame length dependency on the speech signal analytically to understand which frame length is more suitable and effective for male and female speech signals specifically. for the validation of our idea, we have utilized the conventional autocorrelation function (ACf), and state-of-the-art method BaNa. This study puts out a potent idea that will work better for speech processing applications in noisy speech. from experimental results, the proposed idea represents which frame length is more appropriate for male and female speech signals in noisy environments.

关键词： Pitch Estimation fundamental frequency BaNa ACf frame Length

Mycosis fungoides: Epidemiology in Isfahan, Iran

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Journal of Cosmetics, Dermatological Sciences and Applications 2012年第3期2卷 229-233页

作者： farahnaz fatemi Naeini Jamshid Najafian Mansoor Salehi Zahra Azimi parvin Rajabi Department of Genetics and Molecular Biology Medical School Isfahan University of Medical Sciences Isfahan Iran Isfahan Cardiovascular Research Center Isfahan Cardiovascular Research Institue Isfahan University of Medical Sciences Isfahan Iran Isfahan University of Medical Sciences Isfahan Iran Skin and Stem Cell Research Center Tehran University of Medical Sciences Tehran Iran Skin Diseases and Leishmaniasis Research Center Isfahan University of Medical Sciences Isfahan Iran

Background: Mycosis fungoides (Mf) is the most common and indolent form of Cutaneuse T-cell Lymphomas (CTCL), that usually occurs in old adults. Objectives: To determine epidemiologic features and patients characteristics of Mf in Isfahan (Iran). Methods: We performed a retrospective study in Mf clinic of alzahra hospital that is the main center for treatment of Mf patients in Isfahan (Iran) and evaluated clinicopathologic features. Results: In 3 years 25 patients were referred to Alzahra Mf clinic. 18 patients diagnosed as Mf. Seven (38.9%) patients were male and 11 (61.1%) were female with male to female ratio of 1:1.57. The mean age of patients was 41.06 years. 88.9% of our patients were in stages ΙA and ΙB. Conclusion: Most of our patients presented in early stages that were similar to other studies, while male: female ratio is different from other studies.

关键词： Mycosis fungoides Epidemiology Clinical features Iran

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Journal of Cancer Metastasis and Treatment 2017年第1期3卷 209-216页

作者： Nayyereh Aminisani Mehdi fatemi parvin Sarbakhsh Alireza Nikanfar Amirtaher Eftekharsadat Esmat Jafari Epidemiology and Statistics Department Faculty of Health SciencesTabriz University of Medical SciencesTabriz ***Iran Haematology and Oncology Research Center of Tabriz University of Medical Sciences Tabriz ***Iran Pathology Department Emam Reza HospitalTabriz ***Iran.

Aim:The objective of this study was to examine the health-related quality of life(HRQOL),and its correlates among rectal cancer ***:This cross-sectional study was conducted in the northwest of *** cancer survivors were selected from teaching *** was estimated using the European Organization for Research and Treatment of Cancer Quality-of-Life Questionnaire *** about socio-demographic,lifestyle and clinical features of disease was obtained by trained ***:A total of 96 patients were included in this study with mean age of 57.31±14.15 years,54%were male and 59%over 55 years of *** performed poorer than men in many dimensions of HRQOL(Pf symptoms was higher in those who had a higher stage of the *** with insufficient physical activity had a lower score in physical and role dimensions and a higher score of pain and fatigue(Pf disease,and physical activity were important predictive factors of ***:Some clinico-epidemiological factors were associated with a reduced score of HRQOL and its dimensions in this ***,better performance in the presence of a modifiable factor;physical activity,is an opportunity for interventional strategies to improve the HRQOL.

关键词： Health quality of life rectal cancer treatment socioeconomic status

Model of homogenisation for analysing the effect of micrometre pore sizes on the elastic moduli of porous materials

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Acta Mechanica Sinica 2019年第5期35卷 1060-1066页

作者： A.f.fedotov Department of Mechanics Samara State Technical UniversitySamara 443100Russian Federation

A homogenisation model for analysing the effect of micrometre pore sizes on the engineering moduli of elasticity of porous materials was *** the proposed model,the engineering coefficients of localization of total strains(LTS coefficients)are considered instead of the classical strain localization *** a pore,these coefficients represent the ratio of the sum of the strains in the volume of the pore to the sum of the strains in the volume of the porous *** estimate the elastic moduli of a material with an arbitrary pore size,it is sufficient to have information about the elastic moduli and the LTS coefficient of a material with one basic pore ***,in Eshelby's model of equivalent inclusion,a transition to LTS coefficient for material with arbitrary pore size is achieved,and its elasticity moduli are *** results for Young's modulus of porous titanium,with different sizes of spherical pores,completely conform with the experimental *** have obtained a model theoretic estimate of the upper bounds of Young's modulus of porous materials with infinitely small pore *** the spherical pores,the proposed assessment coincides with the upper limits of the Hashin-Shtrikman bounds.

关键词： Elastic moduli Porous material Pore sizes