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Target Capturing in an Ellipsoidal Region for a Swarm of Double Integrator Agents

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IEEE/CAA Journal of Automatica Sinica 2022年第5期9卷 801-811页

作者： Antonio Bono Luigi D'Alfonso Giuseppe Fedele Veysel Gazi IEEE Department of Informatics ModelingElectronics and Systems EngineeringUniversity of CalabriaRende 87036Italy Dept.Electrical and Electronics eng. Faculty of EngineeringMarmara UniversityIstanbul 34722 Department of Control and Automation eng.neering Faculty of Electrical and Electronics EngineeringYildiz Technical UniversityEsenler 34220Turkey

In this paper we focus on the target capturing problem for a swarm of agents modelled as double integrators in any finite space *** agent knows the relative position of the target and has only an estimation of its velocity and *** that the estimation errors are bounded by some known values,it is possible to design a control law that ensures that agents enter a user-defined ellipsoidal ring around the moving *** know the relative position of the other members whose distance is smaller than a common detection ***,in the case of no uncertainty about target data and homogeneous agents,we show how the swarm can reach a static configuration around the moving *** simulations are reported to show the effectiveness of the proposed strategy.

关键词： Agents-based systems cooperative control swarms target-capturing

Numerical Simulation of Tidal Current in a Bay

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China Ocean eng.neering 2000年第1期15卷 121-128页

作者：曾一非 Coll. of Nav. Arch. and Ocean eng. Shanghai Jiaotong University Shanghai 200030 China faculty of eng.neering University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113 Japan

Based on the multilevel model, numerical calculations of tidal current affected by the M-2 tide in the Tokyo Bay have been carried out. The results of calculation are compared with the data observed in the Tokyo Bay and the result calculated by an approximate formula as the Tokyo Bay is regarded as a rectangular bay, and good agreement is found. It is proved that the mathematical model and the calculation method are correct and useable.

关键词： multilevel model Navier-Stokes equations M-2 tide numerical calculation

The Hidden Side of the Story between the Placenta and Preeclampsia: Preliminary Results of a Prospective Cohort of Pregnant Women in Cameroon

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Open Journal of Obstetrics and Gynecology 2024年第4期14卷 610-620页

作者： Junie Annick Metogo Ntsama Ambroise Merci eng.unou Seme Urielle Julie Tchuente Sutchueng.Wilfried Loic Tatsipie Christian Vagoda Henry-Leonard Chatelin Mol Madye Ngo Dingom Felix Essiben Cyrille Claude Noa Ndoua Yann chris eng.Odile Fernande Zeh faculty of Medicine and Biomedical Sciences University of Yaound&#233 I Yaound&#233 Cameroon faculty of Medicine and Pharmaceutical Sciences University of Dschang Dschang Cameroon

Introduction: Pre-eclampsia is a complication of pregnancy that generally occurs in the third trimester. It is associated with a maternal and foetal mortality rate of around 27%. In view of the grim picture painted by this condition for both mother and newborn, studies have been carried out into the early detection of patients at risk of developing pre-eclampsia. These make it possible to introduce pregnancy-specific monitoring and preventive strategies to reduce the incidence of the condition. Objective: To establish the link between placental ultrasound characteristics and the onset of pre-eclampsia. Methodology: A multicentre prospective cohort study was conducted in two hospitals in Yaoundé, namely the Yaoundé Gynaecological Obstetrics and Paediatrics Hospital and the Nkolndongo Health and Social Animation Centre, in the gynaecology and radiology departments over a period of 11 months, from October 2022 to August 2023. It included pregnant women who had undergone obstetric ultrasound between 12 and 18 weeks’ gestation. In addition to routine obstetric ultrasound, we performed obstetric Doppler measurements in these patients. The resistance index of the left and right uterine arteries, the umbilical artery and the placental volume were the characteristics sought. At the end of this examination, two groups were formed: cases (pathological Doppler group) and controls (normal Doppler group). Blood pressure and urine dipstick were taken at each antenatal visit until delivery, then during the immediate postpartum period and finally at 7 days, 21 days and 42 days after delivery. Results: Sixty-seven (67) patients were included. Of these, 35 (47.8%) had pathological Dopplers. Sixteen patients had arterial hypertension associated with proteinuria and were therefore labelled as pre-eclampsia (PE). This gives a prevalence of 23.9%. Fifteen (42.8%) of these patients belonged to the exposed group and one to the unexposed group. The mean IR of the pre-eclampsia patients was s

关键词： Pre-Eclampsia Doppler Ultrasound Placenta

Time Variant Spectral Factorization for Quality improvement of Synthesised Speech

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Time Variant Spectral Factorization for Quality improvement ...

2009 2nd IEEE International Conference on Computer Science and Information Technology（ICCSIT 2009）

作者： Hassan Farsi M.A.Mozaffarian Dept.of Electronic and Electrical eng. Faculty of Eng.Islamic Azad UniversityBirjandIran Dept.of Electronic and Electrical eng. Faculty of Eng.University of BirjandBirjandIran

An adaptive time-domain postfiltering technique based on the synthesis LP filter factorisation is *** is gathered about the relation between the LP filter poles and formants for this *** technique shapes the main formant differently from the other *** locations representing the main formant are modified and optimum shaping constants for each formant are searched to make more narrower main formant bandwidth while maintaining other formant information and more attenuation in valley regions.

关键词： Spectral shaping Synthesis filter LPC filter formant frequencies.

PRECIPITATION HARDENING IN B2-ORDERED NiAl BY Ni_(2)AlTi COMPOUND

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Acta Metallurgica Sinica(eng.ish Letters) 2001年第5期14卷 313-318页

作者： W.H. Tian, K. Ohishi and M. Nemoto 1)Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083, China 2)Department of Materials Science and eng.neering, faculty of eng.neering 36, Kyushu University, Fuk Dept. of Mat. Phys. and eng. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Microstructural variations and correlated hardness changes in B2-ordered NiAl containing fine precipitation of Ni2AlTi have been investigated by means of transmission electron microscopy (TEM) and hardness tests. The amount of age hardening is not large as compared to the large microstructural variations during aging. TEM observations have revealed that the L21-type Ni2AlTi precipitates keep a lattice coherency with the NiAl matrix at the beginning of aging. By longer periods of aging Ni2AlTi precipitates lose their coherency and change their morphology to the globular ones surrounded by misfit dislocations. The temperature dependence of the yield streng.h of precipitate-containing B2-ordered NiAl was investigated by compression tests over the temperature range of 873-1273 K. The fine precipitation of Ni2AlTi was found to enhance greatly the yield streng.h and the high-temperature streng.h is comparable with that of superalloy Mar-M200.

关键词： Aluminum Hardening Mechanical properties Nickel Precipitation (chemical)

COMPARISON STUDY BETWEEN INTEGRATED FIXED FILM ACTIVATED SLUDGE（IFAS）, MEMBRANE BIOREACTOR（MBR） AND CONVENTIONAL ACTIVATED SLUDGE（AS） PROCESSES

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COMPARISON STUDY BETWEEN INTEGRATED FIXED FILM ACTIVATED SLU...

Sixteenth International Water Technology Conference

作者： Abdel Amr M. faculty of eng. Northern Border University Saudi Arabia faculty of eng. Alexandria University AlexandriaEgypt

Comparison study is required to evaluate the treatment efficiency of three alternative secondary treatment processes. These Processes are Integrated Fixed-film Activated Sludge（IFAS）, Membrane Bioreactor（MBR） and Conventional Activated Sludge（AS）. This study is required for a new wastewater treatment plant. The characteristics of the influent domestic wastewater for the proposed plant were measured. The influent wastewater is varied from low, medium and high concentrations. The treated effluent of the wastewater plant should be complied with the reuse regulations of the international standards for several purposed including non-restricted irrigation. The IFAS process has recently become popular for enhanced nitrification and denitrification in aerobic zones because it is an alternative to increasing the volume of treatment plant units to accomplish year round nitrification and nitrogen removal. The mathematical model is used to investigate the performance and treatment capability of the three proposed processes. The GPS-X（version 5.0） simulation program is used in this study to simulate the three treatment processes. The proposed plant model is consisted of three treatment stages. First stage is pretreatment unit（grit chamber）. Second treatment stage is a rectangular primary clarifier. Third treatment stage is the secondary treatment units. The IFAS, AS and MBR processes are used as the three alternative secondary treatment units. It can be concluded from this results that, the treatment efficiency of the IFAS system based on BOD removal is ranged between 97.7 to 98.2 %, and based on TSS removal is ranged between 95.1 to 97.1 % for all cases of operation. Also, the treatment efficiency of the MBR system based on BOD removal is ranged between 98.1 to 99.4 %, and based on TKN removal is ranged between 97.9 to 99.1 % for all cases of operation.

关键词： Integrated Fixed-film Activated Sludge Membrane Bioreactor GPS-X Activated Sludge Biological Treatment

Sustainability of lime stabilized road subgrade in mountainous regions of Türkiye

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Journal of Mountain Science 2023年第8期20卷 2436-2452页

作者： Yavuz ABUT İlknur BOZBEY Ece KURT BAL Department of Transportation eng.neering Faculty of EngineeringYalova UniversityYalova 77200Türkiye Geotechnical eng.neering Division Civil Engineering DepartmentAvcilar CampusIstanbul University-CerrahpasaAvcilar/Istanbul 34320Türkiye Civil eng. M.Sc.&Geoph.Eng.Sentez Geopier FoundationsIstanbul 34320Türkiye

In this paper the use of lime stabilized subgrade for low volume roads in two regions with high mountains and different frost penetration conditions in Türkiye was investigated in terms of design,performance,and *** on unstabilized and stabilized subgrade were designed for two regions(Izmir and Van),covering all climate *** resilient modulus of the lime stabilized subgrade with different soil pulverization levels for non-freezing and freezing conditions were taken from a previous laboratory *** effects were considered in pavement design using two different approaches,including limited subgrade frost penetration method and reduced subgrade streng.h *** application and evaluation were performed for all *** stabilized subgrades significantly reduced the thickness of base courses,and the benefit of lime stabilization was highly dependent on soil pulverization level.A detailed cost analysis on the unstabilized and stabilized cases found that the use of lime stabilization in the subgrade provided significant initial cost *** analysis by using the AASHTO(1993)method and KENPAVE software,and quantity effect of soil pulverization level on the performance of low volume roads from a service life perspective,show that subgrade resilient modulus can be *** is also possible to make correct performance estimation in the *** results of the study show that lime stabilization is a good solution for low volume roads in the mountainous regions of Türkiye.

关键词： Aggregate Surfaced Roads Lime Stabilization Soil Pulverization Levels Road Design Service Life Cost analyses

An Investigation of Metal Flow Behavior between Flat and Overlapping Dies during Copper Forging

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An Investigation of Metal Flow Behavior between Flat and Ove...

2012 2nd International Conference on Materials,Mechatronics and Automation(ICMMA 2012)

作者： Bashir Raddad Mustafa Al-Maghrabi Mech. and Industrial eng. Dept. Faculty of Eng. Tripoli University

Forging in overlapping dies have many industrial applications, and many parts can be produced, with ends of different shapes, and study of such process is important to understand the mechanic, and affect of different variables, Specimen shape, and die geometry. In this work, a study forging of copper specimens between flat dies and overlapping dies having cylindrical, rectangular and square cavities, fixed cross-section area in all specimens and changing the shape of crosssection area. Load displacement relationships are presented and study the effect of friction and constrained volume shapes on flow behavior and effect of (H0/D0) ratio are also investigated. Double extruded part with a hub are produced by the combined forward and backward extrusion forging process, and comparison between the results of constrained volume with double extrusion part was made as well.

关键词：

DISTRIBUTION OF LOCAL FRICTION IN AN OPEN CHANNEL

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DISTRIBUTION OF LOCAL FRICTION IN AN OPEN CHANNEL

第九次河流泥沙国际学术大会

作者： Mirali MOHAMMADI Dept. of Civil eng. Faculty of Eng. The University of Urmia Urmia 57169-33111 Iran Dept. of Civil Eng. Faculty of Eng. The Islamic Azad University Khoy Unit Khoy Iran

＜正＞In open channels, estimation of the local and global friction factor is one of the most important tasks and it sometimes is very difficult. This difficulty arises from the existence of the secondary flow cells and the boundary induced turbulence, both of which affect the distributions of depth-averaged velocity and boundary shear stress, and consequently the local friction factors. A series of measurements was undertaken for velocity and boundary shear stress in fully developed turbulent uniform flow for a smooth open channel. Equations relating the transverse distribution of apparent shear force across the channel boundary for various flow conditions are presented. The experimental overall friction factors were evaluated from the stage-discharge relationships applying the Darcy-Weisbach equation. Using the measured local depth-averaged velocity, Ud, and me local bed shear stress, τb, the local depth-averaged bed friction factor,fb, can be calculated for each lateral position by applying fb=8τb/ρUd 2 . The lateraldistribution of local depth-averaged friction factors show that the distributions are close together for low flow discharges in both sub critical and supercritical flows, but they are more variable for the higher flow discharges. In other words, the normalized local friction factors, fb/f, illustrate that the discrepancy in the higher flow rates are larger than the lower flow rates. More importantly, the Figures show that the local friction factor values tend towards a more constant distribution at high flow rates as the Froude numbers increase. It can also be seen that the local friction factor is found to be decreased from the sidewalls to the channel centerline.

关键词： Open channel flow Friction factor Depth-averaged velocity Boundary shear stress