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The Use of 'In Process' Monitoring Equipment in Heat Treatment Today

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材料热处理学报 2004年第5期25卷 591-596页

作者： dave Plester Datapaq limited Cambridge CB4 OGU UK

This paper looks at how in-process temperature monitoring systems are being increasingly used in heat treatment applications such as surface hardening, annealing, normalizing, tempering etc. We look at the basic equipment required to successfully monitor from within a furnace and how developments such as RF transmission have enhanced the effectiveness of profiling trials to the point where on line adjustments to furnace conditions can be seen and analyzed in real time. We examine how continuous processes can benefit from this type of monitoring and also how routine operations such as furnace surveying in batch furnaces can benefit greatly from in-process monitoring. Advances in software are also considered, showing how packages are now designed to speed up the processing of data in day to day heat treatment operations.

关键词：热处理温度监测器射频传输剖面测量

IQR-based approach for DDoS detection and mitigation in SDN

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Defence Technology（防务技术） 2023年第7期25卷 76-87页

作者： Rochak Swami Mayank dave Virender Ranga Department of Computer Engineering National Institute of TechnologyKurukshetraIndia Department of Information Technology Delhi Technological UniversityDelhiIndia

Software-defined networking(SDN) is a trending networking paradigm that focuses on decoupling of the control logic from the data plane. This decoupling brings programmability and flexibility for the network management by introducing centralized infrastructure. The complete control logic resides in the controller, and thus it becomes the intellectual and most important entity of the SDN infrastructure. With these advantages, SDN faces several security issues in various SDN layers that may prevent the growth and global adoption of this groundbreaking technology. Control plane exhaustion and switch buffer overflow are examples of such security issues. Distributed denial-of-service(DDoS) attacks are one of the most severe attacks that aim to exhaust the controller’s CPU to discontinue the whole functioning of the SDN network. Hence, it is necessary to design a quick as well as accurate detection scheme to detect the attack traffic at an early stage. In this paper, we present a defense solution to detect and mitigate spoofed flooding DDoS attacks. The proposed defense solution is implemented in the SDN controller. The detection method is based on the idea of an statistical measure — Interquartile Range(IQR). For the mitigation purpose, the existing SDN-in-built capabilities are utilized. In this work, the experiments are performed considering the spoofed SYN flooding attack. The proposed solution is evaluated using different performance parameters, i.e., detection time, detection accuracy, packet_in messages, and CPU utilization. The experimental results reveal that the proposed defense solution detects and mitigates the attack effectively in different attack scenarios.

关键词： SDN DdoS IQR Controller CPU utilization Packet_in

Microstructural Characteristics and Mechanical Properties of Low-Alloy, Medium-Carbon Steels After Multiple Tempering

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Acta Metallurgica Sinica(English Letters) 2019年第1期32卷 74-88页

作者： Erfan Abbasi Quanshun Luo dave Owens Materials and Engineering Research Institute Sheffield Hallam University Tyzack Machine Knives Ltd

The microstructure and mechanical properties of NiCrMoV-and NiCrSi-alloyed medium-carbon steels were investigated after multiple tempering. After austenitising, the steels were hardened by oil quenching and subsequently double or triple tempered at temperatures from 250 to 500 °C. The samples were characterised using scanning electron microscopy and X-ray diffraction, while the mechanical properties were evaluated by Vickers hardness testing, V-notched Charpy impact testing and tensile testing. The results showed that the retained austenite was stable up to 400 °C and the applied multiple tempering below this temperature did not lead to a complete decomposition of retained austenite in both steels. It was also found that the microstructure, hardness and impact toughness varied mainly as a function of tempering temperature,regardless of the number of tempering stages. Moreover, the impact toughness of NiCrMoV steel was rather similar after single/triple tempering at different temperatures, while NiCrSi steel exhibited tempered martensite embrittlement after single/double tempering at 400 °C. The observed difference was mainly attributed to the effect of precipitation behaviour due to the effect of alloying additions in the studied steels.

关键词： Medium-carbon steels Multiple tempering Alloying addition Mechanical properties Retained austenite Precipitation behaviour

Intelligent transportation systems for smart cities:a progress review

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Science China(Information Sciences) 2012年第12期55卷 2908-2914页

作者： COOPER dave E State Key Laboratory of Software Development Environment School of Computer Science and EngineeringBeihang University

To better meet the challenge of providing effective,low-cost,energy efficient transport services,the concept of intelligent transport systems(ITS) has been proposed and lauded as an innovative and promising solution for next generation transport *** this paper,the progress of ITS research around the world is briefly reviewed and current challenges are outlined,thereby offering further insight into ITS development for all researchers in this area.

关键词： intelligent transportation systems traffic information smart city

Age and outcomes of primary percutaneous intervention for ST elevation myocardial infarction in a tertiary center are we there yet？

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Journal of Geriatric Cardiology 2015年第3期12卷 263-269页

作者： Vinoda Sharma Manivannan Srinivasan dave Smith Morriston Cardiac Center Swansea Wales United Kingdom

Background Primary percutaneous intervention （PPCI） is the treatment of choice for ST elevation myocardial infarction （STEMI） but robust evidence in the very elderly is lacking. We compared PPCI outcomes between different age quartiles （quartile I 〈 60 years, quartile 2 〉 60 to 〈 70 years, quartile 3 〉 70 to 〈 80 years, quartile 4 〉 80 years）. Methods Retrospective observational analysis of our Morriston Tertiary Cardiac Center （Abertawe Bro Morgannwg University Health Board） patients from 2005 to 2010 with STEMI who underwent PPCI. Resnlts Of 434 patients, 57 （13%） were in quartile 4 （〉 80 years）. In older age quartiles, patients were less likely to receive a drug eluting stent （DES, P = 0.001） or glycoprotein IlbAIIa inhibitor （GPI, P 〈 0.0001）. Increase in age was associated with reduced time to survival （13-coefficient： -0.192, t： -3,70, 95%CI： --4.91 to -1.50, P 〈 0.0001） as was the presence of cardiogenic shock 03-coefficient： -0.194, t = 3.77, 95%CI： -5.26 to -1.65, P 〈 0.0001）. Use of GPI was associated with increased time to survival （p-coefficient： 0.138, t = 2.82, 95%CI： 1.58-8.58, P = 0.005） but older age quartiles were less likely to receive GPI （P 〈 0.0001）. In-hospital mortality （1.8% quartile 1, 3.6% quartile 2, 10.9% quartile 3 and 12.3% quartile 4, P = 0.002） and 1-year mortality （5.4% quartile 1, 5.5% quartile 2, 16.8% quartile 3 and 24.6% quartile 4, P 〈 0.0001, respectively） was significantly higher in older age quartiles. Conclusions Increased short term and intermediate term mortality is seen in the very elderly after PPCI. Age and cardiogenic shock were prognostic factors. Intervention should not be based on age alone and awareness regarding prognostic factors can help improve management.

关键词： Myocardial infarction Primary percutaneous intervention The elderly

Constitutive model for monotonic and cyclic responses of loosely cemented sand formations

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第4期10卷 740-752页

作者： Mojtaba Rahimi dave Chan Alireza Nouri Department of Mechanical Engineering Azad UniversityKhomeinishahr BranchIsfahanIran Department of Civil and Environmental Engineering University of AlbertaEdmontonT6G 2W2Canada China Three Gorges University YichangChina

This paper presents a model to simulate the monotonic and cyclic behaviours of weakly cemented *** elastoplastic constitutive model within the framework of bounding surface plasticity theory is adopted to predict the mechanical behaviour of soft sandstone under monotonic and cyclic loadings. In this model, the loading surface always passes through the current stress state regardless of the type of loading. Destruction of the cementation bonds by plastic deformation in the model is considered as the primary mechanism responsible for the mechanical degradation of loosely cemented sands/weak *** model cyclic response, the unloading plastic and elastic moduli are formulated based on the loading/reloading plastic and elastic moduli. The proposed model was implemented in FLAC2D and evaluated against laboratory triaxial tests under monotonic and cyclic loadings, and the model results agreed well with the experimental observations. For cyclic tests, hysteresis loops are captured with reasonable accuracy.

关键词： Cyclic loading Monotonic loading Cemented sand Plasticity Constitutive model

Changes in sleep parameters following biomimetic oral appliance therapy: A case report

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World Journal of Clinical Cases 2021年第10期9卷 2312-2319页

作者： G dave Singh Shamshudin Kherani Institute of Craniofacial Sleep Medicine Vivos TherapeuticsInc.Highlands RanchCO 80129United States Dental Clinic Kherani Dental at AspenCalgary T3H0N6Canada

BACKGROUND Mandibular advancement devices(MADs)are used to treat mild to moderate obstructive sleep apnea(OSA),but there is a risk that the underlying condition can worsen in the ***,this case report is based on biomimetic oral appliance therapy as an alternative to MADs,which was found to be beneficial in the treatment of a case with severe *** SUMMARY An overnight sleep study was undertaken in a 50-year-old male with excessive daytime sleepiness that lead to a diagnosis of severe OSA as the apnea-hypopnea index(AHI)was found to be 32.8/*** the patient was unable to comply with continuous positive airway pressure therapy and declined surgical intervention,treatment with a MAD was *** 10 years later,another sleep study was performed with no MAD in the mouth,which revealed an AHI of 67.9/*** view of the deterioration in sleep quality,the patient sought alternative treatment and elected on biomimetic oral appliance therapy,using a mandibular repositioning nighttime appliance(mRNA appliance®,Vivos Therapeutics,Inc.,United States).After 10 mo,another sleep study was performed with no device in the patient’s mouth,which revealed an AHI of 11.8/h,a mean oxygen saturation of 94%and a mean oxygen desaturation index of 5.3%while *** analysis of the pre-and post-treatment study models of the upper jaw showed localized size increases of 15%-17%in the premolar regions and 15%-23%in the molar *** In adults with severe OSA that are unable to accept continuous positive airway pressure or surgical treatment,biomimetic oral appliance therapy may be preferable over MADs since biomimetic oral appliance therapy may be able to prevent worsening of sleep parameters by remodeling the nasomaxillary ***-term follow up studies are required to verify these novel findings.

关键词： Obstructive sleep apnea Biomimetic oral appliance therapy Continuous positive airway pressure Mandibular advancement device Case report

A note on Optimal weights and variable selections for multivariate survival data

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Science China Mathematics 2009年第6期52卷 1131-1133页

作者： Zhao Sihai dave Department of Biostatistics Harvard School of Public Health and Dana-Farber Cancer Institute Boston MA 02115 USA

Fan et al. are to be congratulated for this important contribution to the analysis of multivariate failure time data. They have provided three regression parameter estimators for multiple covariates in the marginal ha... 详细信息

关键词： weights multivariate estimating variance marginal hazard likelihood asymptotically estimates choose

The catalytic activity of transition metal oxide nanoparticles on thermal decomposition of ammonium perchlorate

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Defence Technology（防务技术） 2019年第4期15卷 629-635页

作者： Jalpa A. Vara Pragnesh N. dave Shalini Chaturvedi Department of Chemistry K S K V Kachchh University Mundra Road Bhuj 370 001 Gujarat India Department of Chemistry Sardar Patel University Vallabh Vidyangar 388 120 Gujarat India Samarpan Science and Commerce College Gandhinagar Gujarat India

The catalytic proficiency of three MONs for AP thermal decomposition was studied in this work.A chemical co-precipitation method was used for synthesis of MONs(CuZnO,CoZnO,and NiZnO)and their characterization carried out by utilizing XRD,FTIR,and *** TGA/DSC technique was employed for the investigation of the catalytic proficiency of MONs on the *** DSC data were used for measuring activation energy of catalyzed AP by using Ozawa,Kissinger,and Starink *** MONs were much sensitive for AP decomposition,and the performance of AP decomposition was further *** all the MONs,the CuZnO exhibits higher catalytic action than others and decomposition temperature of AP is descending around 117℃ by *** reduction in the activation energy was noticed after the incorporation of MONs in AP.

关键词： Metal oxide nanoparticles(MONs) Ammonium perchlorate(AP) Catalytic activity Activation energy