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Design and optimization of cSP power plants for Pakistan:a comparative study

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clean Energy 2023年第3期7卷 690-704页

作者： Kashif liaqat Juan c.Ordonez Department of Mechanical Engineering FAMU-FSU College of EngineeringEnergy and Sustainability Centerand Center for Advanced Power SystemsFlorida State UniversityTallahasseeFL 32310USA

Despite having very high solar irradiance,Pakistan still does not have any installed concentrated solar power(cSP)*** studies have shown that multiple locations within the country are suitable for cSP plants,but there is limited availability of comprehensive comparative ***,this article presents a comparative analysis of different cSP technologies in Pakistan,focusing on their potential to address the country’s energy *** study evaluates the pros and cons of different cSP technologies at various locations through site assessment,modelling,optimization and economic analysis using the System Advisor *** and Nawabshah were selected as the locations for modelling multiple scenarios of 100-MW plants,using central receiver systems,parabolic trough collectors and linear Fresnel *** plants were integrated with thermal energy storage and the storage capacity was optimized using parametric *** results showed that a central receiver system for the location of Quetta was the most favourable option,with an annual energy yield of 622 GWh at 7.44 cents/kWh,followed by a central receiver system for Nawabshah(608 GWh,9.03 cents/kWh).This study is the first to show that switching between line-concentrated and point-concentrated cSP technologies can open new opportunities for sites in Pakistan with relatively high solar resources,resulting in a 21.3%reduction in the levelized cost.

关键词： concentrated solar power parabolic trough collector linear Fresnel reflector central receiver System Advisor Model Pakistan

Finite element implementation of strain-hardening Drucker-Prager plasticity model with application to tunnel excavation

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Underground Space 2017年第3期2卷 168-174页

作者： K.liu S.l.chen Department of civil&Environmental Engineering Louisiana State UniversityBaton RougeLAUSA

This paper presents a finite element implementation of a strain-hardening Drucker-Prager model and its application to tunnel *** computational model was constructed based on the return mapping scheme,in which an elastic trial step was first executed,followed by plastic correction involving the Newton-Raphson method to return the predicted state of stresses to the supposed yield *** combining the plastic shear hardening rule and stress correction equations,the loading index for the strain-hardening Drucker-Prager model was *** is therefore possible to update the stresses,elastic and plastic strains,and slope of the yield locus at the end of each incremental *** an illustrative example,an integration algorithm was incorporated into ABAQUS through the user subroutine UMAT to solve the tunnel excavation problem in strain-hardening Drucker-Prager rock *** obtained numerical results were found to be in excellent agreement with the available analytical solutions,thus indicating the validity and accuracy of the proposed UMAT code,as well as the finite element model.

关键词： Strain-hardening Drucker-Prager model Finite element method UMAT code Tunnel excavation

FASTER–RcNN for Skin Burn Analysis and Tissue Regeneration

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computer Systems Science & Engineering 2022年第9期42卷 949-961页

作者： c.Pabitha B.Vanathi Department of computer Science and Engineering SRM Valliammai Engineering CollegeChennai603203India

Skin is the largest body organ that is prone to the environment mostspecifically. Therefore the skin is susceptible to many damages, including burndamage. Burns can endanger life and are linked to high morbidity and mortalityrates. Effective diagnosis with the help of accurate burn zone and wound depthevaluation is important for clinical efficacy. The following characteristics areassociated with the skin burn wound, such as healing, infection, painand stressand keloid formation. Tissue regeneration also takes a significant amount of timefor formation while considering skin healing after a burn injury. Deep neural networks can automatically assist in the extraction of features from a burn image. Inour approach to burn wound analysis and regeneration of the tissue of the skinburn wound, we use the Faster RcNN (Regional convolutional Neural Network),which is based on their severity of the burn wound. The success rates of skin curefor burning injuries can be dramatically increased with the use of different skinreplacements. Our objective is to analyze different deep learning techniques thatmay help to analyze and classify burn wounds in a superficial, partial and complete thickness, while treating burn wounds more accurately. The application ofFaster RcNN effectively classifies wound without first degree, second and thirddegree confusion, thus providing a suitable solution to burning wounds. Theadvancement in the field of profound training offers an important path in the fieldof the processing and burning of trauma.

关键词： Faster R-cNN skin burn deep learning RPN computer vision

Molecular level simulations on multi-component systems --a morphology prediction method

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Frontiers of chemical Science and Engineering 2013年第1期7卷 49-54页

作者： c. ScHMIDT J. UlRIcH center for Engineering Science Thermal Process Engineering Martin Luther University Halle-Wittenberg D-06099 Halle (Saale) Germany

The crystal morphology grown from a solution composed of an organic solvent, solute and additive can be predicted reliably by a computational method. Modeling the supersaturated solution as liquid phase is achieved by employing commercial software. The molecular composition of this solution is a required input parameter. The face specific diffusion coefficient of the solid （crystal surface） and liquid （solution） system is determined using the molecular dynamics procedure. The obtained diffusion coefficient is related to the specific face growth rate via the attachment energy of the pure morphology. The significant improvements are achieved in the morphology prediction because the investigation on the face growth rates in a complex growth environment （as multi-component solutions with additives） can be carried out based on the diffusion coefficients.

关键词： crystallization morphology molecular dynamics solution

On Quasi-Reduced Quadratic Forms

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Acta Mathematica Sinica,English Series 2010年第8期26卷 1425-1448页

作者： E. DUBOIS c. lEVESQUE Eugene Dubois UMR 6138 CNRS Dep. de mathematiques et mecanique BP 5186 U. de Caen Basse-Normandie 14032 Caen France claude levesque CICMA et Departement de mathematiques et de statistique U. Laval Quebec P. Qudbec Canada G1K 7P4

With the help of continued fractions, we plan to list all the elements of the set Q△ = {aX2 ＋ bXY ＋ cY2 ： a,b, c ∈Z, b2 - 4ac = △ with 0 ≤ b 〈 √△}of quasi-reduced quadratic forms of fundamental discriminant △. As a matter of fact, we show that for each reduced quadratic form f = aX2 ＋ bXY ＋ cY2 = （a, b, c） of discriminant △〉0（and of sign σ（f） equal to the sign of a）, the quadratic forms associated with f and defined by {〈a＋bu＋cu2,b＋2cu.c〉},with 1≤σ（f）u≤b/2｜c｜（whenever they exist）, 〈c,-b-2cu,a＋bu＋cu2〉 with b/2｜c｜≤σ（f）u≤[w（f）]=[b＋√△/2｜c｜], are all different from one another and build a set I（f） whose cardinality is #I（f）={1＋[ω（f）],when（2c）｜b,[ω（f）],when （2c）｜b. If f and g are two different reduced quadratic forms, we show that I（f） ∩ I（g） = Ф. Our main result is that the set Q△ is given by the disjoint union of all I（f） with f running through the set of reduced quadratic forms of discriminant △〉0. This allows us to deduce a formula for #（Q△） involving sums of partial quotients of certain continued fractions.

关键词： Quadratic forms reduced forms equivalence of forms class numbers quadratic fields,continued fractions

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PI3K-AKT-mTOR signaling in prostate cancer progression and androgen deprivation therapy resistance

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Asian Journal of Andrology 2014年第3期16卷 378-386页

作者： Merritt P Edlind Andrew c Hsieh Perelman School of Medicine University of Pennsylvania Philadelphia PA USA Division of Hematology/Oncology and Department of Internal Medicine University of California San Francisco CA USA.

Prostate cancer （Pca） is the second most common malignancy among men in the world. castration-resistant prostate cancer （cRPc） is the lethal form of the disease, which develops upon resistance to first line androgen deprivation therapy （ADT）. Emerging evidence demonstrates a key role for the PI3K-AKT-mTOR signaling axis in the development and maintenance of cRPc. This pathway, which is deregulated in the majority of advanced Pcas, serves as a critical nexus for the integration of growth signals with downstream cellular processes such as protein synthesis, proliferation, survival, metabolism and differentiation, thus providing mechanisms for cancer cells to overcome the stress associated with androgen deprivation. Furthermore, preclinical studies have elucidated a direct connection between the PI3K-AKT-mTOR and androgen receptor （AR） signaling axes, revealing a dynamic interplay between these pathways during the development of ADT resistance. Thus, there is a clear rationale for the continued clinical development of a number of novel inhibitors of the PI3K pathway, which offer the potential of blocking cRPc growth and survival. In this review, we will explore the relevance of the PI3K-AKT-mTOR pathway in Pca progression and castration resistance in order to inform the clinical development of specific pathway inhibitors in advanced Pca. In addition, we will highlight current deficiencies in our clinical knowledge, most notably the need for biomarkers that can accurately predict for response to PI3K pathway inhibitors.

关键词： androgen receptor cRPc kinase inhibitors mTOR prostate cancer PI3K resistance

Transhiatal versus transthoracic esophagectomy for esophageal cancer

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World Journal of Gastroenterology 2010年第30期16卷 3804-3810页

作者： J camilo Barreto Mitchell c Posner Section of General Surgery and Surgical Oncology Department of SurgeryUniversity of Chicago Pritzker School of Medicine5841 S. Maryland AveMC 5094ChicagoIL 60637United States

Esophageal cancer continues to represent a formidable challenge for both patients and clinicians. Relative 5-year survival rates for patients have improved over the past three decades, probably linked to a combination of improved surgical outcomes, progress in systemic chemotherapy and radiotherapy, and the increasing acceptance of multimodality treatment. Surgical treatment remains a fundamental component of the treatment of localized esophageal adenocarcinoma. Multiple approaches have been described for esophagectomy, which can be thematically grouped under two major categories: either transthoracic or transhiatal. The main controversy rests on whether a more extended resection through thoracotomy provides superior oncological outcomes as opposed to resection with relatively limited morbidity and mortality through a transhiatal approach. After numerous trials have addressed these issues, neither approach has consistently proven to be superior to the other one, and both can provide excellent short-term results in the hands of experienced surgeons. Moreover, the available literature suggests that experience of the surgeonand hospital in the surgical management of esophageal cancer is an important factor for operative morbidity and mortality rates, which could supersede the type of approach selected. Oncological outcomes appear to be similar after both procedures.

关键词： Esophageal cancer Transhiatal esophageal resection Transthoracic esophageal resection

Exact solution and dynamic buckling analysis of a beam-column system having the elliptic type loading

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Applied Mathematics and Mechanics(English Edition) 2010年第10期31卷 1317-1324页

作者： H.S.ARTEM l.AYDIN Department of Mechanical Engineering Izmir Institute of Technology

This paper presents a closed form solution to the dynamic stability problem of a beam-column system with hinged ends loaded by an axial periodically time-varying compressive force of an elliptic type,i.e.,a1cn 2（τ,k 2）＋a2sn 2（τ,k 2）＋a3dn 2（τ,k 2）.The solution to the governing equation is obtained in the form of Fourier sine *** resulting ordinary differential equation is solved *** the exact analytical solutions to the dynamic buckling problems is ***,the availability of exact solutions can provide adequate understanding for the physical characteristics of the *** this study,the frequency-response characteristics of the system,the effects of the static load,the driving forces,and the frequency ratio on the critical buckling load are also investigated.

关键词： dynamic buckling exact solution stability-instability Jacobi elliptic functions

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Petrogenesis of shoshonitic granitoids,eastern India:Implications for the late Grenvillian post-collisional magmatism

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Geoscience Frontiers 2014年第6期5卷 821-843页

作者： B.Goswami c.Bhattacharyya Department of Geology University of Calcutta35 Ballygunge Circular RoadKolkata 700 019India

Many elongated, lenticular plutons of porphyritic granitoids are distributed mainly near the southern and northern margin of the chhotanagpur Gneissic complex （cGc） which belongs to the EW to ENE-WSW tending 1500 km long Proterozoic orogenic belt amalgamat ng the North and South Indian cratonic blocks. The late Grenvillian （1071 ±64 Ma） Raghunathpur porphyritic granitoid gneiss （PGG） batholith comprising alkali feldspar granite, granite, granodiorite, tonalite, quartz syenite and quartz monzonite intruded into the granitoid gneisses of southeastern part of cGc in the Purulia district, West Bengal and is aligned with ENE-WSW trending North Purulia sr^ear zone, Mineral chemistry, geochemistry, physical condition of crystallization and petrogenetic model of Raghunathpur PGG have been discussed for the first time. The petrographic and geochemical features （including major and trace- elements, mineral chemistry and S7Sr/S6Sr ratio） suggest these granitoids to be classified as the shosh- onitic type. Raghunathpur batholith was emplaced at around 800 ~c and at 6 kbar pressure tectonic discrimination diagrams reveal a post-collision tectonic setting while structural studies reveal its emplacement in the extensional fissure of North Purulia shear zone. l＇he Raghunathpur granitoid is compared with some similar granitoids of Europe and china to draw its petrogenetic model. Hybridi- zation of mantle-generated enriched mafic magma and crustal magma at lower crust and later fractional crystallization is proposed for the petrogenesis of this PGG. Mafic magma generated in a post-collisional extension possibly because of delamination of subducting slab. Raghunathpur batholith had emplaced in the cGc during the final amalgamation （~ 1.0 Ga） of the North and South Indian cratonic blocks. Granitoid magma, after its generation at depth, was transported to its present level along megadyke channel, ways within shear zones.

关键词： Granitoids Petrology Geochemistry Shoshonitic Post-collisiooal chhotanagpur Gneissic complex

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