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SEQUENTIAL CONVEX PROGRAMMING METHODS FOR SOLVING LARGE TOPOLOGY OPTIMIZATION PROBLEMS： IMPLEMENTATION AND COMPUTATIONAL RESULTS

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Journal of Computational Mathematics 2005年第5期23卷 491-502页

作者： Qin Ni ch.Zillober K.Sch.ttkowski Nanjing University of Aeronautics and Astronautics 210016 Nanjing China Department of Computer Science University of BayreuthD-95440 BayreuthGermany

In this paper, we describe a method to solve large-scale structural optimization problems by sequential convex programming （SCP）. A predictor-corrector interior point method is applied to solve the strictly convex subproblems. The SCP algorithm and the topology optimization approach.are introduced. Especially, different strategies to solve certain linear systems of equations are analyzed. Numerical results are presented to show the efficiency of the proposed method for solving topology optimization problems and to compare different variants.

关键词： Large scale optimization Topology optimization Sequential convex programming method Predictor-corrector interior point method Method of moving asymptotes

Estimating rock properties using sound signal dominant frequencies during diamond core drilling operations

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Journal of Rock Mech.nics and Geotech.ical Engineering 2019年第4期11卷 850-859页

作者： ch.Vijaya Kumar Harsha Vardhan ch.S.N.Murthy N.C.Karmakar Department of Mining Engineering National Institute of Technology KarnatakaSurathkalIndia Indian Institute of Tech.ology (BHU) VaranasiIndia

In many engineering applications such.as mining,geotech.ical and petroleum industries,drilling operation is widely *** drilling operation produces sound by-product,which.could be helpful for preliminary estimation of the rock ***,determination of rock properties is very difficult by the conventional methods in terms of high accuracy,and thus it is expensive and *** this context,a new tech.ique was developed based on the estimation of rock properties using dominant frequencies from sound pressure level generated during diamond core drilling ***,sound pressure level was recorded and sound signals of these sound frequencies were analyzed using fast Fourier transform (FFT).Rock drilling experiments were performed on five different types of rock samples using computer numerical control (CNC) drilling mach.ne BMV 45 *** simple linear regression analysis,mathematical equations were developed for various rock properties,*** compressive strength,Brazilian tensile strength,density,and dominant frequencies of sound pressure *** developed models can be utilized at early stage of design to predict rock properties.

关键词： Rock properties Sound pressure level Fast Fourier transform (FFT) Sound signal Core drilling Dominant frequencies

Animal life in the ch.moautotrophic ecosystem of the hypogenic groundwater cave of Ayyalon (Israel): A summing up

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Natural Science 2013年第4期5卷 7-13页

作者： F. D. Por ch. Dimentman A. Frumkin I. Naaman Department of Ecology Evolution and Behavior and National Collections of Natural History The Hebrew University of Jerusalem Jerusalem Israel Department of Geography The Hebrew University of Jerusalem Jerusalem Israel Department of Geography The Hebrew University of Jerusalem Jerusalem Israel The Hermann Institute of Earth Sciences The Hebrew University of Jerusalem Jerusalem Israel

Seven years after the discovery of the ch.moautotrophic sulfidic groundwater site of the Ayyalon cave, its macrofauna can be fully reviewed. It consists of six endemic stygobiont and troglo-biont crustaceans and other arthropods and two species still with unclear status. The taxonomic list is followed by brief discussions on the systematics of the species as well as by a few comments concerning the eventual broader zoogeographical and speleological implications of the Ayyalon faunistic findings, as they appeared in literature.

关键词： ch.moautotrophy Sulfidic Groundwaters Hypogenic Pool Ophel Biome Extremophily Anaerobism Ayyalon Cave Thermosbaenacea

Water Runoff Estimation Using Geographical Information System (GIS) for Alrakhmah Basin Valley Northeast of Iraq

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Engineering（科研） 2020年第6期12卷 315-324页

作者： Abdulrazaq K. Abdulwahd Mohammed ch. Liejy Mohanad A. Sulaiman Nadhir Al-Ansari Tech.ical Institute of Haweeja Northern Technical University Kirkuk Iraq General Commission for Running/Irrigation and Drainage Kirkuk Province Ministry of Water Resources Kirkuk Iraq Lulea University of Tech.ology Lulea Sweden

The lack of water resources in many regions is the main ch.llenge for the human being and to extended investigations. Water resources controlling and management is essential in the areas depending on the seasonal rainfall. This research.aims to estimate the surface water runoff for Basin of Alrakhmah Valley located in the southwestern part of Kirkuk Province in northeastern of Iraq. Analyzing of Spatial data and Digital Elevation Model (DEM) data has been conducted using Geographic Information System (GIS) to estimate the hydrological properties for the watershed valley with 158.5 km2 surface area. The results showed that watershed valley type is from the fifth rank with a longitudinal shape and topography percentage of 0.568. The watershed textures found to be 3.24 and the drain density 1.5 at 3.49 river branch.ng. Finally, the annual estimated surface water retreat according to the morpho-hydro climatic elements found to be 0.01286233 milliard cubic meter.

关键词： Geographic Information Systems (GIS) Digital Elevation Model (DEM) Spatial Data Watershed

ENHANCEMENT　OF　INTRAMOLECULAR　EXCIMER　FORMATION　AND　PHOTODIMERIZATION　OF　POLYETHERS　BEARING　NAPHTHALENE　ch.OMOPHORES　VIA　COMPLEXATION　WITH　CATIONS

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ch.nese ch.mical Letters 1995年第2期6卷 113-116页

作者： Tung, ch.Wu, LZ Acad Sinica Inst Photog Chem Beijing 100101 Peoples R China

The fluorescence spectra and photodimerization of naphthalene end-laballed poly(ethylene glycol) oligomers (N-Pn-N) in methanol in the prescence of alkali cations have been investigated. The ion enhances or inhibits intramolecular excimer formation and photodimerization of N-Pn-N, depending on the size of the ion and the length of the polyether ch.in. This observation suggests that the polyether ch.in binds the ion, thus adopts a crown ether-like conformation.

关键词： VIA ch.OMOPHORES COMPLEXATION WITH NAPHTHALENE AND BEARING

Complex dynamics and bifurcation analysis for a Beverton-Holt population model with Allee effect

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生物数学学报:英文版 2023年第7期16卷 165-196页

作者： Karima Mokni Mohamed ch.ch.oui MRI Laboratory FacultéPolydisciplinaire Khouribga Sultan Moulay Slimane University BP:145 Khouribga Principale25000Kingdom of Morocco

In this paper,we have derived a discrete evolutionary Beverton-Holt population *** model is built using evolutionary game theory methodology and takes into consideration the strong Allee effect related to predation *** have discussed the existence of the positive fixed point and examined its asymptotic ***,we demonstrated that the derived model exhibits Neimark-Sacker bifurcation when the maximal predator intensity is at lower *** ch.otic behaviors are justified ***,to avoid these ch.otic features and ach.eve asymptotic stability,we implement two ch.os control methods.

关键词： Evolutionary game theory asymptotic stability Neimark-Sacker bifurcation ch.os control

Artificial intelligence in gastroenterology:where are we heading?

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Frontiers of Medicine 2020年第4期14卷 511-517页

作者： Joseph JY Sung Nich.las ch.Poon Institute of Digestive Disease Faculty of MedicineThe Chinese University of Hong KongHong KongChina Big Data Decision Analytic Cancer The Chinese University of Hong KongHong KongChina

Artificial intelligence(AI)is coming to medicine in a big *** making diagnosis in various medical conditions,following the latest advancements in scientific literature,suggesting appropriate therapies,to predicting prognosis and outcome of diseases and conditions,AI is offering unprecedented possibilities to improve care for *** is a field that AI can make a significant *** is partly because the diagnosis of gastrointestinal conditions relies a lot on image-based investigations and procedures(endoscopy and radiology).AI-assisted image analysis can make accurate assessment and provide more information than conventional *** integration of genomic,epigenetic,and metagenomic data may offer new classifications of gastrointestinal cancers and suggest optimal personalized *** managing relapsing and remitting diseases such.as inflammatory bowel disease,irritable bowel syndrome,and peptic ulcer bleeding,convoluted neural network may formulate models to predict disease outcome,enhancing treatment *** and surgical robots can also assist surgeons in conducting gastrointestinal *** the advancement and new opportunities are exciting,the responsibility and liability issues of AI-assisted diagnosis and management need much.deliberations.

关键词： artificial intelligence endoscopy robotics gastrointestinal diseases

De Broglie–Bohm Interpretation of Canonical Quantum Cosmology Implies Early Stages of the Universe Dominated by Radiation

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Communications in Theoretical Physics 2013年第12期60卷 691-694页

作者： ch.ng Han Siong Shahidan Radiman Sch.ol of Applied Physics Faculty of Science and Technology Universiti Kebangsaan Malaysia

The Einstein＇s genera/relativity is formulated in the Hamiltonian form for a spatia/ly Bat, isotropic and homogeneous universe. Subsequently, we perform the canonical quantization procedure to the Hamiltonian to obtain the Wheeler-DeWitt equation. Solving the Wheeler-DeWitt equation and employing the de Broglie-Bohm interpretation to the wave function of the universe, we obtain a new version of spatia/ly fiat Friedmann equation for the early universe where the scale factor of the universe is taken to be sufilcientlv small.

关键词： de Broglie-Bohm interpretation canonical quantum cosmology Friedmann equation Wheeler-DeWitt equation

The Transient Time-Resolved Absorption Spectra of 1-Naphthylacetic Acid

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ch.nese ch.mical Letters 2000年第3期11卷 261-262页

作者： Li, W Tung, ch.Ye, JP ch.nese Acad Sci Inst Photog Chem Beijing 100101 Peoples R China

The transient absorption spectra of 1-naphthylacetic acid in tetrahydrofuran have been obtained by laser flash photolysis tech.ique. The transient species bands are at 509, 535 and 553 nm. These peak intensities incre... 详细信息

关键词： transient spectra laser ch.mistry 1-naphthylacetic acid