检索结果-南通市图书馆

Study of Reinforcement Distribution,Adhesion between Layers,and Porosity Induced by FDM

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

材料科学与工程（中英文A版） 2021年第2期11卷 56-62页

作者： Arthur Wernke rafael dos santos Leonardo santos Manuel Barcelos Jr Emmanuel Lima Laboratório Associado de Sensores e Materiais Instituto Nacional de Pesquisas Espaciais(INPE)Avenida dos Astronautas 1758São Josédos Campos-SP 12245-970Brazil Faculdade do Gama(FGA) Universidade de Brasília(UnB)St.Leste Projeção AGama-DF 72444-240Brazil

This study aims to understand the distribution of reinforcement material in the matrix,evaluate the adherence between layers,and determine the air gap between printing *** printed the specimen with two different composite materials,Polylactic Acid(PLA)reinforced with acrylic particles,and another filament reinforced with short carbon *** the observations of the samples,we used a Confocal *** estimated the porosity of the material by comparing the expected mass with that achieved after *** pixel count,after binarization,we found the average percentage of acrylate *** showed fair distribution through the PLA matrix even after the manufacturing *** determination of fibers alignment was made by binarization of image,together with k-means and edge *** combination of methods allows estimating the fiber alignment by orientation straight *** manufacturing process did not offer good alignment of the fibers,even with the filament initially well aligned.

关键词： 3D printing porosity in 3D printed parts 3D printed composite materials

Concerns about the application of resistance exercise with blood-flow restriction and thrombosis risk in hemodialysis patients

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Sport and Health Science 2024年第4期13卷 548-558,F0003页

作者： Hugo de Luca Correa Lysleine Alves Deus Dahan da Cunha Nascimento Nicholas Rolnick Rodrigo Vanerson Passos Neves Andrea Lucena Reis Thais Branquinho de Araujo Carmen Tzanno-Martins Fernanda Silveira Tavares Luiz Sinesio Silva Neto Claudio Avelino Rodrigues santos Paolo Lucas Rodrigues-Silva Fernando Honorato Souza Vitoria Marra da Motta Vilalva Mestrinho rafael Lavarini dos santos Rosangela Vieira Andrade Jonato Prestes Thiago dos santos Rosa Post-graduate Program of Physical Education Catholic University of BrasıliaBrasılia 71966-700Brazil The Human Performance Mechanic Lehman CollegeNew YorkNY 10011USA Clinical Group Home Dialysis Center and RenalClass Sao Paulo 01239-040Brazil Department of Medicine Catholic University of BrasıliaBrasılia 71966-700Brazil Faculty of Medicine Federal University of TocantinsTocantins 77001-090Brazil Embrapa Genetic Resources and Biotechnology Brasılia 70770-917Brazil Graduate Program of Genomic Sciences and Biotechnology Brasılia 71966-700Brazil

Background:Hemodialysis(HD) per se is a risk factor for *** the growing body of evidence on blood-flow restriction(BFR) exercise in HD patients,identification of possible risk factors related to the prothrombotic agent D-dimer is required for the safety and feasibility of this training *** aim of the present study was to identify risk factors associated with higher D-dimer levels and to determine the acute effect of resistance exercise(RE) with BFR on this ***:Two hundred and six HD patients volunteered for this study(all with a glomerular filtration rate of 70 years old),and HD ***,RE+BFR significantly increases D-dimer after 4 *** with borderline baseline D-dimer levels(400-490 ng/mL) displayed increased risk of elevating D-dimer over the normal range(≥500 ng/mL).Conclusion:These results identified factors associated with a heightened prothrombotic state and may assist in the screening process for HD patients who wish to undergo RE+BFR.D-dimer and/or other fibrinolysis factors should be assessed at baseline and throughout the protocol as a precautionary measure to maximize safety during RE+BFR.

关键词： Blood-flow restriction Chronic kidney disease Coagulation Hemodialysis Vascular occlusion exercises

GPR Tomographic Imaging of Concrete Tubes and Steel/Plastic Tanks Buried in IAG/USP Geophysical Test Site, Brazil

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

International Journal of Geosciences 2017年第5期8卷 647-658页

作者： Jorge Luís Porsani Emerson Rodrigo Almeida Bruno Poluha Vinícius rafael Neris dos santos Universidade de Sã o Paulo Instituto de Astronomia Geofísica e Ci&ecirc ncias Atmosféricas Departamento de Geofísica. Rua do Mat&atilde o 1226 Butant&atilde S&atilde o Paulo Brazil

In this paper, the Ground Penetrating Radar (GPR) method was used to characterize concrete tubes and steel/plastic tanks buried in IAG/USP test site. The microwave tomography was used to improve the GPR images, aiming to retrieve the geometry of the targets. The numerical modeling studies also were done in order to predict the GPR results of the buried targets and to give more reliability to the results interpretation. The targets were installed in the first shallow geophysical test site of the Brazil located at Institute of Astronomy, Geophysics, and Atmospheric Science (IAG) of the University of S?o Paulo (USP). GPR profiles of 200 MHz (shielded bistatic antennas) were acquired along three lines containing concrete tubes and steel/plastic tanks buried in subsoil. The concrete tubes show a hyperbolic reflector for the top, and the vertical tube also presented a reflection on its bottom. The horizontal steel tanks were characterized by a strong GPR reflection on their top. The empty plastic tank shows a strong reflector for the top with normal polarity. On the other hand, the plastic tank filled with water shows a weaker reflector for its top characterized by the inverted polarity of GPR signal when compared with empty plastic tank. The plastic tank filled with water also went characterized by the strong reflection to its bottom, being a good indicative to interpret GPR data on target in subsoil with some types of fluid inside of tank. The results of polarity difference for the top of tank can be used as guide pattern to identify buried tank empty or filled with water. The application of microwave tomography to the GPR data permitted to determine the position and get a good identification of the edges of the targets studied. The numeric modeling presented a good accordance with real data reducing the ambiguities in interpretation of results. These results can be used as a reference, and they can be extrapolated for areas where there is no subsurface information.

关键词： Ground Penetrating Radar (GPR) Microwave Tomography Numeric Modeling Concrete Tubes Steel Tanks Plastic Tanks IAG/USP Test Site Brazil

Depth Estimates of Buried Utility Systems Using the GPR Method: Studies at the IAG/USP Geophysics Test Site

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Geosciences 2017年第5期8卷 726-742页

作者： Bruno Poluha Jorge Luís Porsani Emerson Rodrigo Almeida Vinicius rafael Neris dos santos Scott Joseph Allen Universidade de Sã o Paulo Instituto de Astronomia Geofísica e Ciências Atmosféricas Departamento de Geofísica. Rua do Mat&atilde o S&atilde o Paulo Brazil Universidade Federal de Pernambuco. Departamento de Arqueologia. Avenida Professor Moraes Rego Cidade Universitária Pernambuco Brazil

Identifying underground utilities and predicting their depth are fundamental when it comes to civil engineering excavations, for example, to install or repair water, sewer, gas, electric systems and others. The accidental rupture of these systems can lead to unplanned repair costs, delays in completing the service, and risk injury or death of workers. One way to detect underground utilities is using the GPR-Ground Penetrating Radar geophysical method. To estimate depth, the travel time (two-way travel time) information provided by a radargram is used in conjunction with ground wave velocity, which depends on the dielectric constant of materials, where it is usually assumed to be constant for the area under investigation. This procedure provides satisfactory results in most cases. However, wrong depth estimates can result in damage to public utilities, rupturing pipes, cutting lines and so on. These cases occur mainly in areas that have a marked variation of water content and/or soil lithology, thus greater care is required to determine the depth of the targets. The present work demonstrates how the interval velocity of Dix (1955) can be applied in radargram to estimate the depth of underground utilities compared to the conventional technique of constant velocity applied to the same data set. To accomplish this, synthetic and real GPR data were used to verify the applicability of the interval velocity technique and to determine the accuracy of the depth estimates obtained. The studies were carried out at the IAG/USP test site, a controlled environment, where metallic drums are buried in known positions and depths allowing the comparison of real to estimated depths. Numerical studies were also carried out aiming to simulate the real environment with variation of dielectric constant in depth and to validate the results with real data. The results showed that the depths of the targets were estimated more accurately by means of the interval velocity technique in contrast

关键词： GPR Depth Estimation Interval Velocity Constant Velocity Urban Planning IAG/USP Test Site Brazil

GPR Tomography as Support for an Archaeological Excavation in AripuanãIndigenous Cemetery, Amazon Region, Brazil

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Geosciences 2017年第10期8卷 1264-1277页

作者： Jorge Luís Porsani Renato Kipnis Vinícius rafael Neris dos santos Emerson Rodrigo Almeida Iris Fernandes Universidade de Sã o Paulo Instituto de Astronomia Geofísica e Ciências Atmosféricas Departamento de Geofísica S&atilde o Paulo Brazil Scientia Consultoria Científica S&atilde o Paulo Brazil

We present here a series of Ground Penetrating Radar (GPR) survey carried out in different areas of the Dardanelos 1 archaeological site in order to generate information about subsurface anomalies associated with archaeological material that could be use in decision making within the environmental licensing process of the Dardanelos Hydroelectric Power Plant, located near of the Aripuan? city, Mato Grosso State, northwest region of Brazil. GPR surveys with 200 MHz antenna were carried out in two blocks aiming to locate archaeological resources and features. The analysis of GPR 2D and 3D results allowed detecting anomalous regions characterized by hyperbolic reflections, shallow elongated continuous targets with high amplitudes, as well as sub-horizontal reflectors. Microwave tomography allowed estimating the geometry of the GPR anomalies sources. Excavations were done by archaeologists at the locations where hyperbolic anomalies were found, revealing interesting structures related to urns in the middle of a rich in organic matter consisting of black and ceramic materials up to about 1 m deep. The first sub-horizontal reflector at approximately 1 m depth is related to the base of the black soil layer rich in organic matter and the second sub-horizontal reflector between 2 and 3 m deep suggests a lithological change or may be related to presence of the water table. The continuous elongated shallow targets observed in the depth slices are related to tree roots in the middle of the archaeological strata. The GPR results guided archaeological excavations, reduced the time and costs involved in research, and contributed to the preservation of Brazilian historical heritage.

关键词： Ground Penetrating Radar (GPR) Microwave Tomography Archaeology Anthropogenic Soil Dardanelos Hydroelectric Power Plant Amazon Region Brazil

Response to Commentary by Dr. Matthew J. Clarkson on

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Sport and Health Science 2024年第5期13卷 670-671页

作者： Hugo de Luca Corrêa Lysleine Alves Deus Dahan da Cunha Nascimento Nicholas Rolnick Rodrigo Vanerson Passos Neves Andrea Lucena Reis Thais Branquinho de Araújo Carmen Tzanno-Martins Fernanda Silveira Tavares Luiz Sinésio Silva Neto Cláudio Avelino Rodrigues santos Paolo Lucas Rodrigues-Silva Fernando Honorato Souza Vitória Marra da Motta Vilalva Mestrinho rafael Lavarini dos santos Rosangela Vieira Andrade Jonato Prestes Thiago dos santos Rosa Post-graduate Program of Physical Education Catholic University of BrasıliaBrasılia 71966-700Brazil The Human Performance Mechanic Lehman CollegeNew YorkNY 10011USA Clinical Group Home Dialysis Center and RenalClass Sao Paulo 01239-040Brazil Department of Medicine Catholic University of BrasıliaBrasılia 71966-700Brazil Faculty of Medicine Federal University of TocantinsTocantins 77001-090Brazil Embrapa Genetic Resources and Biotechnology Brasılia 70770-917Brazil g Graduate Program of Genomic Sciences and Biotechnology Brasılia 71966-700Brazil

Dear editor:We sincerely thank Matthew *** for his insightful commentary1 on our recent publication in the Journal of Sport and Health Science.2 Clarkson's pioneering work in the development and application of blood flow restriction (BFR) exercise protocols has undeniably laid the groundwork for subsequent investigations in this field,including our own.(3-6)His commentary not only highlights the relevance and timeliness of our study but also offers valuable perspectives on refining safety considerations for intradialytic BFR exercise among hemodialysis patients.

关键词： patients application flow

Variations in Atmospheric Electromagnetism and Their Impacts on Mortality Rates in the Southern and Northeastern Regions of Brazil

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Atmospheric and Climate Sciences 2025年第1期15卷 248-274页

作者： Rose Ane Pereira de Freitas Julio Renato Quevedo Marques Reynerth Pereira da Costa Júlia Alves Menezes Isabela de Brito Ferreira Rhavena Barbosa dos santos Ulisses Eugenio Cavalcanti Confalonieri Department of Meteorology Federal University of Pelotas (UFPel) Pelotas Brazil National Observatory (ON) Ministry of Science Rio de Janeiro Brazil Laboratory of Analysis and Development of Indicators for Sustainability (LADIS) Division of Impacts Adaptation and Vulnerability (DIIAV) National Institute for Space Research (INPE) So Jos dos Campos Brazil Department of Parasitology Institute of Biological Sciences Federal University of Minas Gerais (UFMG) Belo Horizonte Brazil Department of Nursing and Medicine Federal University of Viosa (UFV) Viosa Brazil Department of Food Technology Federal Fluminense University (UFF) and Rene Rachou Institute Fiocruz Belo Horizonte Brazil

This study examines the relationship between geomagnetic indices and mortality rates from specific diseases in the Northeast (NE) and Southern (S) regions of Brazil from 1996 to 2020. Solar activity data, including the Ap and Sudden Ionospheric Disturbance (SID) indices, were sourced from the World Data Center, while mortality data were obtained from the Mortality Information System (SIM-DATASUS). Acute Myocardial Infarction (AMI) emerged as the leading cause of mortality, with average death rates of 60.4, 56.8, and 58.3 deaths per 100,000 inhabitants in Pernambuco (PE), Rio Grande do Sul (RS), and Paraná (PR), respectively. Temporal analysis revealed a consistent upward trend in AMI mortality across most states, except for Santa Catarina (SC). Seasonal patterns identified through Principal Component Analysis (PCA) demonstrated that geomagnetic and climatic indices influenced mortality differently across regions and seasons. The Ap geomagnetic index was strongly correlated with higher AMI mortality rates during summer, while the SID index showed greater relevance during winter. A dipole phenomenon was observed, with AMI deaths increasing alongside geomagnetic activity in the S region but showing an inverse relationship in the NE region. These findings highlight the significant influence of geomagnetic variations on public health, particularly cardiovascular mortality. The study underscores the need for further research into the biological mechanisms underlying these associations and recommends the development of early warning systems and targeted preventive measures to mitigate the potential health impacts of geomagnetic disturbances, especially for vulnerable populations.

关键词： Solar Activity Cardiovascular Mortality Geomagnetic Disturbances

Capacitorless Solid-state Power Filter for Single-phase DC-AC Converters

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CES Transactions on Electrical Machines and Systems 2024年第3期8卷 367-377页

作者： Haitham Kanakri Euzeli C.dos santos Purdue University Electrical and Computer Engineering DepartmentIndianapolisIN46202 USA

Converters rely on passive filtering as a crucial element due to the high-frequency operational characteristics of power *** filtering methods involve a dual inductor-capacitor(LC)cell or an inductor-capacitor-inductor(LCL)***,capacitors are susceptible to wear-out mechanisms and failure ***,the necessity for monitoring and regular replacement adds to an elevated cost of ownership for such *** utilization of an active output power filter can be used to diminish the dimensions of the LC filter and the electrolytic dc-link capacitor,even though the inclusion of capacitors remains an indispensable part of the *** paper introduces capacitorless solid-state power filter(SSPF)for single-phase dc-ac *** proposed configuration is capable of generating a sinusoidal ac voltage without relying on *** proposed filter,composed of a planar transformer and an H-bridge converter operating at high frequency,injects voltage harmonics to attain a sinusoidal output *** design parameters of the planar transformer are incorporated,and the impact of magnetizing and leakage inductances on the operation of the SSPF is *** analysis,supported by simulation and experimental results,are provided for a design example for a single-phase *** total harmonic distortion observed in the output voltage is well below the IEEE 519 *** system operation is experimentally tested under both steady-state and dynamic conditions.A comparison with existing technology is presented,demonstrating that the proposed topology reduces the passive components used for filtering.

关键词： Solid-state power filter(SSPF) Capacitorless topology Active output power filter(AOF) Planar transformer Electrolytic capacitor Lifetime Wear-out mechanisms

The use of Vis-NIR-SWIR spectroscopy in the prediction of soil available ions after application of rock powder

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Information Processing in Agriculture 2024年第1期11卷 26-44页

作者： Marlon Rodrigues Josiane Carla Argenta Everson Cezar Glaucio Leboso Alemparte Abrantes dos santos ÖnderÖzal Amanda Silveira Reis Marcos rafael Nanni Department of Agronomy State University of MaringáColombo AvenueMaringá87020900Brazil Department of Plant and Soil Sciences Mississippi State UniversityMS 39762USA International Agricultural Research and Training Center Izmir 35660Turkey

Some of the problems attributed to traditional laboratory analyses that limit the correct assessment of the nutrient contents in the soil are time requirements and high cost of the soil nutrient *** solve these problems,a study was carried out to evaluate the use of visible,near-infrared,and short-wave infrared(Vis-NIR-SWIR)spectroscopy in the prediction of soil available ions submitted to the application of rock *** study was carried out on an Arenosol in ParanavaíCity/***(rock powders)were arranged within a split-plot system designed in randomized blocks with four *** was cultivated for 14 months after the application of rock ***,96 soil samples were collected for measuring the pH and available ions P,K^(+),Ca^(2+),Mg^(2+),S-SO_(4)^(2-),Si,Cu^(2+),Fe^(2+),Mn^(2+),and Zn^(2+)as well as spectral reading through a Vis-NIR-SWIR spectroradiometer to predict the soil chemical attributes through the partial least square regression(PLS)*** results showed that the elements K^(+),Ca^(2+),Mg^(2+),Cu^(2+),and Fe^(2+)could be predicted with a reasonable rightness degree(R^(2)_(p)>0.50,RPDp>1.40)from spectral ***,for the attributes pH,P,S-SO_(4)^(2-),Si,Mn^(2+),and Zn^(2+),there were no satisfactory models(R^(2)_(p)<0.50,RPDp<1.40).Thus,the application of rock powder changed the spectral curves and,because of that,allows the building of PLS models to predict the elements K^(+),Ca^(2+),Mg^(2+),Cu^(2+),and Fe^(2+).Therefore,Vis-NIR-SWIR spectroscopy is a promising alternative to the routine analyses of soil fertility since it has advantages such as fast analytical speed,low cost,easy to operate,non-destructive,and environmentally friendly,because it does not use harmful chemicals.

关键词： Alternative inputs Available Ions Multivariate analysis Soil Spectroscopy