检索结果-南通市图书馆

Microstructural Characterization and Tensile Behavior of Rutile(TiO_2)-Reinforced AA6063 Aluminum Matrix Composites Prepared by Friction Stir Processing

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2019年第1期32卷 52-62页

作者： Sahayam Joyson Abraham Isaac Dinaharan Jebaraj David raja Selvam Esther Titilayo Akinlabi Department of Mechanical Engineering V V College of Engineering Department of Mechanical Engineering Science University of Johannesburg Auckland Park Kingsway Campus Department of Mechanical Engineering Karunya Institute of Technology and Sciences

Rutile(TiO_2) particle-reinforced aluminum matrix composites were prepared by friction stir processing. The microstructure was studied using conventional and advanced characterization techniques. TiO_2 particles were found to be dispersed uniformly in the composite. Clusters of TiO_2 particles were observed at a higher particle content of 18 vol%. The interface between the TiO_2 particle and the aluminum matrix was characterized by the absence of pores and reactive ***-grain boundaries, ultra-fine grains and dislocation density were observed in the composites. TiO_2 particles improved the mechanical properties of the composites. However, a drop in tensile strength was observed at a higher particle content due to cluster formation. All the prepared composites exhibited ductile mode of fracture.

关键词： Aluminum matrix composites Friction stir processing Rutile Microstructure Tensile strength

A Comprehensive Systematic Review: Advancements in Skin Cancer Classification and Segmentation Using the ISIC Dataset

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第9期140卷 2131-2164页

作者： Madiha Hameed Aneela Zameer Muhammad Asif Zahoor raja Department of Computer Sciences Pakistan Institute of Engineering and Applied SciencesNilore50700Islamabad Future Technology Research Center National Yunlin University of Science and TechnologyDouliou64002TaiwanChina Directorate of IT Services University of GujratGujrat50700Pakistan

The International Skin Imaging Collaboration(ISIC)datasets are pivotal resources for researchers in machine learning for medical image analysis,especially in skin cancer *** datasets contain tens of thousands of dermoscopic photographs,each accompanied by gold-standard lesion diagnosis *** challenges associated with ISIC datasets have spurred significant advancements,with research papers reporting metrics surpassing those of human *** cancers are categorized into melanoma and non-melanoma types,with melanoma posing a greater threat due to its rapid potential for metastasis if left *** paper aims to address challenges in skin cancer detection via visual inspection and manual examination of skin lesion images,processes historically known for their *** notable advancements in machine learning and deep learning models,persistent challenges remain,largely due to the intricate nature of skin lesion *** review research on convolutional neural networks(CNNs)in skin cancer classification and segmentation,identifying issues like data duplication and augmentation *** explore the efficacy of Vision Transformers(ViTs)in overcoming these challenges within ISIC dataset *** leverage their capabilities to capture both global and local relationships within images,reducing data duplication and enhancing model ***,ViTs alleviate augmentation issues by effectively leveraging original *** a thorough examination of ViT-based methodologies,we illustrate their pivotal role in enhancing ISIC image classification and *** study offers valuable insights for researchers and practitioners looking to utilize ViTs for improved analysis of dermatological ***,this paper emphasizes the crucial role of mathematical and computational modeling processes in advancing skin cancer detection methodologies,highlighting their significance in improving algorithmic

关键词： Medical image skin cancer classification skin cancer segmentation international skin imaging collaboration convolutional neural network deep learning

SDN assisted Stackelberg Game model for LTE-WiFi offloading in 5G networks

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Digital Communications and Networks 2019年第4期5卷 268-275页

作者： Sudha Anbalagan Dhananjay Kumar Gunasekaran raja Alkondan Balaji Department of Computer Science and Engineering SRM Institute of Science and TechnologyKattankulathurIndia Department of Information Technology Anna UniversityChennaiIndia Department of Computer Technology Anna UniversityChennaiIndia

The data traffic that is accumulated at the Macro Base Station(MBS)keeps on increasing as almost all the people start using mobile *** MBS cannot accommodate all user’s demands,and attempts to offload some users to the nearby small cells so that the user could get the expected *** the MBS to offload data traffic to an Access Point(AP),it should offer an optimal economic incentive in a way its utility is ***,the APs should choose an optimal traffic to admit load for the price that it gets from *** balance this tradeoff between the economic incentive and the admittance load to achieve optimal offloading,Software Defined Networking(SDN)assisted Stackelberg Game(SaSG)model is *** this model,the MBS selects the users carefully to aggregate the service with AP,so that the user experiencing least service gets aggregated *** MBS uses the Received Signal Strength Indicator(RSSI)value of the users as the main parameter for aggregating a particular user for a contract period with LTE and *** player involved in the game tries to maximize their payoff utilities,and thus,while incorporating those utilities in real-time scenario,we obtain maximum throughput per user which experiences best data service without any lack in Quality of Experience(QoE).Thus,the proposed SaSG model proves better when compared with other game theory models,and hence an optimal data offloading is achieved.

关键词： LTE WiFi Aggregation Software Defined Networking Stackelberg Game

Screening of Rice Cultivars for Morpho-Physiological Responses to Early-Season Soil Moisture Stress

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rice science 2017年第6期24卷 322-335页

作者： Bhupinder SINGH Kambham raja REDDY Edilberto Diaz REDONA Timothy WALKER Department of Plant and Soil Sciences Mississippi State UniversityMississippi 39762USA Delta Research and Extension Center Mississippi State UniversityMississippi 38776USA Horizon Ag.LLC 8275 Tournament DriveSuite 255MemphisTennessee 38125USA

The majority of rice(Oryza sativa L.) produced in the southern USA is drill-seeded and grown under upland-like conditions because permanent flooding is established after the four-leaf stage. Therefore, rice during the seedling growth stage will be subjected to variable soil moisture content. A greenhouse experiment was conducted to evaluate the performance of 15 rice cultivars commonly grown in Mississippi of USA under early-season soil moisture stress. Twenty morpho-physiological parameters of rice seedlings subjected to three different levels(100%, 66% and 33% field capacity) of soil moisture, from 10 to 30 d after sowing, were measured. Significant moisture stress × treatment interaction(P < 0.001) was observed for most of the parameters. Further, the total drought response index(TDRI) was developed to score the cultivars for drought tolerance with the variation from 26.88 to 36.21. Accordingly, the cultivars were classified into different groups of tolerance. The cultivars CL152 and CL142-AR were classified as the least and the most tolerant to drought based on TDRI and standard deviation, respectively. Even though both total root(R^2 = 0.98) or shoot(R^2 = 0.76) drought responses indices were positively correlated with TDRI, root traits were important in deriving the indices. Therefore, TDRI could be used to select cultivars for drought tolerance in a given environment and develop rice varieties with early-season drought tolerance. However, further research is needed to identify and characterize tolerance at other stages to assist breeding programs in rice.

关键词： drought field capacity morpho-physiological parameter Oryza sativa root shoot soil moisture content total drought response index

Metastasis of hepatocellular carcinoma to Virchow's node:Have the tumor cells gone astray?

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2007年第6期6卷 650-652页

作者： raja Selvasekaran Jijo Velliyappillil Cherian Jayanthi Venkataraman Department of Gastroenterology Stanley Medical College & Hospital Chennai India

BACKGROUND: Virchow’s node is a common site for metastasis in cancers of the stomach and pancreas. It is rarely involved in hepatocellular carcinoma. METHOD: We report on a patient with hepatoma who had metastasis to the left supraclavicular node at presentation. RESULTS: This 25-year-old man presented with abdominal pain, fever, weight loss, hard nodular hepatomegaly and a hard, fixed left supraclavicular lymphadenopathy. He was hepatitis B surface antigen positive, had elevated serum alpha-fetoprotein levels, and transabdominal imaging showed a space-occupying lesion in the right lobe of the liver. Fine needle aspiration of the left supraclavicular node revealed a poorly differentiated carcinoma. CONCLUSION: Metastasis to the Virchow-Trosier node in hepatoma, although uncommon, can occur probably via the hepatic node and then through the thoracic duct.

关键词： hepatoma metastasis Virchow-Trosier node

A theoretical study on the elastic deformation of cellular phase and creation of necrosis due to the convection reaction process inside a spherical tumor

在线全文

学校读者我要写书评

暂无评论

International Journal of Biomathematics 2016年第6期9卷 273-306页

作者： Bibaswan Dey G. P. raja Sekhar Department of MathematicsIndian Institute of Technology Kharagpur Kharagpur 721302 West Bengal India

Several biological processes, such as convective nutrient transport and convective drug delivery in biological tissues involves the transvascular and interstitial movement of biofluids. This work addresses transvascular and interstitial transport of nutrient inside a spherical tumor. Most of the biological tissues behave like deformable porous materiM and show mechanical behavior towards the fluid motion, due to the fact, that the forces like the drag, which is associated with fluid flow may compress the tissue material. On the macroscopic level, transport of solutes like nutrients, drug molecules, etc. within the tumor interstitial space is modeled. The hydrodynamic problem is treated with biphasic mixture theory under steady state and spherically symmetry situation. The transvascular transport of nutrient is modeled with the modified Sterling＇s equation. The present model describes the overall nutrient distribution and predicts various criteria for the necrosis formation inside the tumor. Present study justifies that the parameters, which controls the nutrient supply to the tumor interstitial space through the blood vessel network inside the tumor, competes with reversible nutrient consumption kinetics of the tumor cells. This study also finds the role of some of those parameters on the deformation of cellular phase of the tumor as a consequence of interstitial fluid flow.

关键词： Tumor vasculature isolated tumor biphasic mixture theory effectivenessfactor necrotic core.

Impact of surgery for chronic pancreatitis on the risk of pancreatic cancer:Untying the Gordian knot

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2021年第27期27卷 4371-4382页

作者： raja Kalayarasan Sankar Narayanan Jayaprakash Sahoo Pazhanivel Mohan Department of Surgical Gastroenterology JIPMERPuducherry 605006India Department of Endocrinology JIPMERPuducherry 605006India Department of Medical Gastroenterology JIPMERPuducherry 605006India

Pancreatic ductal adenocarcinoma is an aggressive tumor with poor long-term *** pancreatitis(CP)is considered a risk factor for the development of pancreatic cancer(PC).Persistent pancreatic inflammation and activation of pancreatic stellate cells play a crucial role in the pathogenesis of CPrelated PC by activating the oncogene *** genetic mutations increase the possibility of recurrent and persistent pancreatic inflammation,they are not directly associated with the development of *** studies suggest that early surgical intervention for CP might have a protective role in the development of CP-related ***,the physician faces the clinical question of whether early surgical intervention should be recommended in patients with CP to prevent the development of ***,the varying relative risk of PC in different subsets of CP underlines the complex gene-environment interactions in the disease ***,it is essential to stratify the risk of PC in each individual *** review focuses on the complex relationship between CP and PC and the impact of surgical intervention on PC *** proposed risk stratification based on the genetic and environmental factors could guide future research and select patients for prophylactic surgery.

关键词： Chronic pancreatitis Pancreatic adenocarcinoma Pancreatic cancer Surgery Hereditary pancreatitis Pancreatitis

Path Planning of Quadrotors in a Dynamic Environment Using a Multicriteria Multi-Verse Optimizer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2021年第11期69卷 2159-2180页

作者： raja Jarray Mujahed Al-Dhaifallah Hegazy Rezk Soufiene Bouallègue Research Laboratory in Automatic Control(LARA) National Engineering School of Tunis(ENIT)University of Tunis El ManarTunis1002Tunisia Department of Systems Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia College of Engineering at Wadi Addawaser Prince Sattam Bin Abdulaziz UniversityAl-Kharj11911Saudi Arabia Department of Electrical Engineering Faculty of EngineeringMinia UniversityMinia61517Egypt High Institute of Industrial Systems of Gabès(ISSIG) University of GabèsGabès6011Tunisia

Paths planning of Unmanned Aerial Vehicles(UAVs)in a dynamic environment is considered a challenging task in autonomous flight control *** this work,an efficient method based on a Multi-Objective MultiVerse Optimization(MOMVO)algorithm is proposed and successfully applied to solve the path planning problem of quadrotors with moving *** a path planning task is formulated as a multicriteria optimization problem under operational *** proposed MOMVO-based planning approach aims to lead the drone to traverse the shortest path from the starting point and the target without collision with moving *** vehicle moves to the next position from its current one such that the line joining minimizes the total path length and allows aligning its direction towards the *** choose the best compromise solution among all the non-dominated Pareto ones obtained for compromise objectives,the modified Technique for Order Preference by Similarity to Ideal Solution(TOPSIS)is investigated.A set of homologous metaheuristics such as Multiobjective Salp Swarm Algorithm(MSSA),Multi-Objective Grey Wolf Optimizer(MOGWO),Multi-Objective Particle Swarm Optimization(MOPSO),and Non-Dominated Genetic Algorithm II(NSGAII)is used as a basis for the performance *** results and statistical analyses show the superiority and effectiveness of the proposed MOMVO-based planning *** obtained results are satisfactory and encouraging for future practical implementation of the path planning strategy.

关键词： Quadrotors path planning dynamic obstacles multi-objective optimization global metaheuristics TOPSIS decision-making Friedman statistical tests

Takotsubo syndrome with underlying pheochromocytoma

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 Geriatric Cardiology 2021年第12期18卷 1068-1070页

作者： Tooba Sahar Asaad Akbar Khan raja Wajid Shabbir Cardiology Department Shifa International HospitalIslamabadPakistan

Takotsubo cardiomyopathy(TTC),also re-ferred as broken heart syndrome,is a type of non-ischemic cardiomyopathy usually preceded by exposure to significant physical or emotional stress.[1]Reported by Sato,et al.[2]in 1990 for the first time,the condition resembles acute coronary syndrome(ACS),characterised by chest pain and dyspnoea.[3]ST-segment elevation and/or T wave inversion and pathological Q waves are pre-sent in almost 40%of patients on electrocardiogram.[4]It is recently established that TTC causative factor is not only an acute emotional stress,but also sudden intracranial events,including haemorrhage,trauma and ischemic events;acute medical diseases such as sepsis and surgical interventions;increased secre-tion of endogenous catecholamines(pheochromocy-toma);and administration of exogenous catechola-minergic agents can contribute to the disease *** has been recognized by the American College of Cardiology/American Heart Association as a dis-tinctive form of reversible cardiomyopathy.

关键词： acute cardiomyopathy al.