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An Accurate Dynamic Forecast of Photovoltaic Energy Generation

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Fluid Dynamics & Materials Processing 2022年第6期18卷 1683-1698页

作者： Anoir Souissi Imen Guidara Maher Chaabene Giuseppe Marco Tina Moez Bouchouicha Signal Image et Maîtrise de l’Energie(SIME Laboratory)Tunis1008Tunisia Dipartimento di Ingegneria Elettrica Elettronica e InformaticaCatania95125Italy Laboratoire LIS-Equipe SIIM Département GMP IUT Toulon83041France

The accurate forecast of the photovoltaic generation(PVG)process is essential to develop optimum installation sizing and pragmatic energy planning and management.This paper proposes a PVG forecast model for a PVG/Battery installation.The forecasting strategy is built on a Medium-Term Energy Forecasting(MTEF)approach refined dynamically every hour(Dynamic Medium-Term Energy Forecasting(DMTEF))and adjusted by means of a Short-Term Energy Forecasting(STEF)strategy.The MTEF predicts the generated energy for a day ahead based on the PVG of the last 15 days.As for STEF,it is a combination between PVG Short-Term(ST)forecasting and DMTEF methods obtained by selecting the least inaccurate PVG estimation every 15 minutes.The algorithm results are validated by measures taken on a 3 KWp standalone PVG/Battery installation.The proposed approaches have been integrated into a management algorithm in order to make a pragmatic decision to ensure load supply considering relevant constraints and priorities and guarantee the battery safety.Simulation results show that STEF provides accurate results compared to measures in stable and perturbed days.The NMBE(Normalized Mean Bias Error)is equal to-0.58%in stable days and 26.10%in perturbed days.

关键词： Energy Forecasting MTEF DMTEF STEF ARIMA model photovoltaic energy

Assessment of the Recent Hydromorphological Features of Nokoue Lake and Its Channels (South-East Benin)

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Open Journal of Modern Hydrology 2024年第1期14卷 33-55页

作者： Tètchodiwèï Julie-Billard Yonouwinhi Gérard Alfred Franck Assiom d’Almeida Felix Kofi Abagale Akuemaho Virgile Onésime Akowanou laboratory of Applied Hydrology (LHA) National Institute of water (INE) African Centre of Excellence for Water and Sanitation (C2EA) University of Abomey-Calavi (UAC) Cotonou Benin International Chair in Mathematical Physics and Applications (ICMPA–UNESCO Chair) University of Abomey-Calavi (UAC) Cotonou Benin laboratory of Geology Mining and Environment (LGME) Faculty of Science and Technology (FAST) University of Abomey-Calavi (UAC) Cotonou Benin West African Centre for Water Irrigation and Sustainable Agriculture (WACWISA) University of Development Studies (UDS) Tamale Ghana laboratory of Sciences and Technology for Water and Environment (LSTEE) University of Abomey-Calavi (UAC) Cotonou Benin

Based on 2022 and 2023 hydrometric data and satellite images (Sentinel 2022, SPOT 2010), this study aims to present the Nokoué Lake and its channels’ re-cent hydromorphological characteristics. Integrating flow, tributary morphology, and topography data determined specific power values along the axes studied. The values obtained range from 2.69 to 12.92 W/m2 for Ouémé River and 2.46 to 10.99 W/m2 for Sô River. The resulting water erosion on banks and bottoms is of linear, areolar, or gully and claw types. Lake bathymetry varies from -0.5 to -2.6 m (low flow period) and -1 to -4 m;in the Ouémé, Sô, and Totchè rivers, it varies from -5 m to -7 m, reaching -10 m at the Cotonou channel entrance (flood period). Bathymetric profiles reveal varied “U”, “V” and “Intermediate” bottom morphologies, influenced by erosion/sedimentation processes and human activities. The flow facies identified are lentic in the northern tributaries and lotic in the Cotonou and Totchè canals. Spatial analysis identified nine (09) thematic classes. In 2022, the surface area of the water body has increased from 274 km2 at low water to 280 km2 at high water, whereas in 2010 (a recent year of exceptional flooding), the surface area was 270 km2 at low water and 277 km2 at high water. Significant changes in land use are observed between 2010 and 2022. The floodplain area decreased slightly, from 421 km2 in 2010 (year of exceptional flooding) to 419 km2 in 2022. The evolution of land use shows a progressive expansion of the urban environment to the detriment of the natural environment. In the medium to long term, this trend could threaten the hydromorphological balance and even the existence of this important lagoon ecosystem.

关键词： Nokoué Lake Ouémé River Sô River Cotonou Channel Hydromorphology

Fast and Accurate Thoracic SPECT Image Reconstruction

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Computer Modeling in Engineering & Sciences 2022年第5期131卷 881-904页

作者： Afef Houimli Issam Ben Mhamed Bechir Letaief Dorra Ben-Sellem University of Tunis El Manar Higher Institute of Medical Technologies of TunisResearch Laboratory in Biophysics and Medical Technologies LR13ES07Tunis1006Tunisia University of Tunis Higher National School of Engineers of TunisSignal Image and Energy Management Laboratory:LR13 ES03 SIMEENSITMontfleury1008Tunisia Faculty of Medicine of Tunis University of Tunis El ManarTunis1007Tunisia Nuclear Medicine Department Salah AZAIEZ InstituteTunis1006Tunisia

In Single-Photon Emission Computed Tomography(SPECT),the reconstructed image has insufficient contrast,poor resolution and inaccurate volume of the tumor size due to physical degradation factors.Generally,nonstationary filtering of the projection or the slice is one of the strategies for correcting the resolution and therefore improving the quality of the reconstructed SPECT images.This paper presents a new 3D algorithm that enhances the quality of reconstructed thoracic SPECT images and reduces the noise level with the best degree of accuracy.The suggested algorithm is composed of three steps.The first one consists of denoising the acquired projections using the benefits of the complementary properties of both the Curvelet transformand theWavelet transforms to provide the best noise reduction.The second step is a simultaneous reconstruction of the axial slices using the 3D Ordered Subset Expectation Maximization(OSEM)algorithm.The last step is post-processing of the reconstructed axial slices using one of the newest anisotropic diffusion models named Partial Differential Equation(PDE).The method is tested on two digital phantoms and clinical bone SPECT images.A comparative study with four algorithms reviewed on state of the art proves the significance of the proposed method.In simulated data,experimental results show that the plot profile of the proposed model keeps close to the original one compared to the other algorithms.Furthermore,it presents a notable gain in terms of contrast to noise ratio(CNR)and execution time.The proposed model shows better results in the computation of contrast metric with a value of 0.68±7.2 and the highest signal to noise ratio(SNR)with a value of 78.56±6.4 in real data.The experimental results prove that the proposed algorithm is more accurate and robust in reconstructing SPECT images than the other algorithms.It could be considered a valuable candidate to correct the resolution of bone in the SPECT images.

关键词： SPECT image resolution correction thoracic SPECT images wavelet transform curvelet transforms 3D-OSEM PDE

Four-coordinate disilyl cobalt(Ⅱ)complexes with NHC ligation:Synthesis,characterization,and reactivity

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Chinese Chemical Letters 2024年第3期35卷 292-298页

作者： Lan Zhou Dongyang Wang Chengbo Yang Liang Deng College of Chemistry and Materials Science University of Science and Technology of ChinaHefei 230026China State Key laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

Silyl cobalt species are putative intermediates in cobalt-catalyzed transformations of hydrosilanes.However,their reactivity has remained poorly understood.Reported here is the investigation on four-coordinate disilyl Co(Ⅱ)complexes with N-hetereocyclic carbene ligation.The reactions of[(ICy)_(2)Co(vtms)](ICy=1,3-dicyclohexylimidazol-2-ylidene,vtms=vinyltrimethylsilane)with primary and secondary hydrosilanes(3 equiv.)furnish the four-coordinate disilyl complexes[trans-(ICy)_(2)Co(SiHRR')_(2)](SiHRR'=SiH_(2)Mes,1;SiH_(2)Ph,2;SiH_(2)Cy,3;SiHPh_(2),4;SiHEt_(2),5)in moderate to good yields.The structures of 1,2 and 4 were established by single-crystal X-ray diffraction.Solution magnetic susceptibility measurement and EPR spectroscopy indicate their low-spin nature(S=1/2).Reactivity studies on 4 led to the establishment of the conversions of 4 to the disilyl dihydride Co(Ⅲ)complex[K(THF)][(ICy)_(2)Co(H)_(2)(SiHPh_(2))_(2)]_n(6)and the fluorosilyl Co(Ⅱ)complex[(ICy)_(2)Co(THF)(SiFPh_(2))][BF_(4)](7)when 4 was treated with excess amount of K and AgBF_(4),respectively,in THF.These conversions hint at the high activity of low-valent and high-valent disilyl cobalt species[trans-(ICy)_(2)Co(SiHPh_(2))_(2)]^(1-)and[trans-(ICy)_(2)Co(SiHPh_(2))_(2)]^(2+).Complex 4 is reactive toward terminal alkynes,but inert toward alkenes and internal alkynes.The reactions of 4 with terminal alkynes CyC≡CH and Me_(3)SiC≡CH(3 equiv.)yield the Co(Ⅱ)complexes[(ICy)_(2)Co(C≡CCy)_(2)](8)and[(ICy)_(2)Co(C≡Csime_(3))((sime_(3))C=CH_(2))](9),respectively,along with H_(2)SiPh_(2)and alkynylsilanes RC≡CSiHPh_(2)(R=Cy,sime_(3)),whereas the reaction with 4-CF_(3)C_(6)H_(4)C≡CH(3 equiv.)produce[(ICy)_(2)Co(C≡CAr)((Ar)C=CH(SiHPh_(2))C=CHAr)](Ar=4-CF_(3)C_(6)H_(4))(10)and H_(2)SiPh_(2).These reactions are proposed to involveσ-bond metathesis reactions between alkyne C(sp)-H bonds and Co-Si bonds in 4.Complexes 6–10 have been characterized by NMR spectroscopy,X-ray diffraction study,and elemental analysis.

关键词： Disilyl Cobalt N-Heterocyclic carbene Four-coordinate

False Positive Responses Optimization for Intrusion Detection System

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Journal of Information Security 2014年第2期5卷 19-36页

作者： Jalal Baayer Boubker Regragui Aziz Baayer sime laboratory ENSIAS Mohammed V Suissi University Rabat Morocco

In Intrusion Detection Systems (IDS), the operation costs represent one of the big challenges for researchers. They are apart from the IDS cost acquisition and they comprise the costs of maintenance, administration, response, running and errors reactions costs. In the present paper, we focus on the missed reactions which include False Positive (FP) and False Negative (FN) reactions. For that a new optimization cost model is proposed for IDS. This optimization proposes a minimal interval where the IDSs work optimally. In simulation, we found this interval as a trade-off between the damage costs and the FP.

关键词： Cost Model Intrusion Detection System False Positive False Negative Damage Costs and Optimization

On abelian 2-ramification torsion modules of quadratic fields

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Science China Mathematics 2022年第12期65卷 2459-2482页

作者： Jianing Li Yi Ouyang Yue Xu Research Center for Mathematics and Interdisciplinary Sciences Shandong UniversityQingdao 266237China CAS Wu Wen-Tsun Key laboratory of Mathematics University of Science and Technology of ChinaHefei230026Chin Hefei National laboratory Hefei 230088China

For a number field F and a prime number p, the Z_(p)-torsion module of the Galois group of the maximal abelian pro-p extension of F unramified outside p over F, denoted by T_(p)(F), is an important subject in the abelian p-ramification theory. In this paper, we study the group T_(2)(F) = T_(2)(m) of the quadratic field F = Q(m_(1/2)). Firstly, assuming m > 0, we prove an explicit 4-rank formula for quadratic fields that rk4(T_(2)(-m))= rk2(T_(2)(-m))-rank(R), where R is a certain explicitly described Rédei matrix over F_(2). Furthermore, using this formula, we obtain the 4-rank density formula of T_(2)-groups of imaginary quadratic fields. Secondly, for l an odd prime, we obtain the results about the 2-power divisibility of orders of T_(2)(±l) and T_(2)(±2l), both of which are cyclic 2-groups. In particular, we find that #T_(2)(l) ≡ 2#T_(2)(2l) ≡ h_(2)(-2l)(mod 16) if l ≡ 7(mod 8),where h_(2)(-2l) is the 2-class number of Q((-2l)_(1/2)). We then obtain the density results for T_(2)(±l) and T_(2)(±2l)when the orders are small. Finally, based on our density results and numerical data, we propose distribution conjectures about T_(p)(F) when F varies over real or imaginary quadratic fields for any prime p, and about T_(2)(±l)and T_(2)(±2l) when l varies, in the spirit of Cohen-Lenstra heuristics. Our conjecture in the T_(2)(l) case is closely connected to Shanks-sime-Washington’s speculation on the distributions of the zeros of 2-adic L-functions and to the distributions of the fundamental units.

关键词： quadratic fields density theorems abelian 2-ramification

Synthesis of pyrrolidinyl-ethylene fluorenyl rare-earth metal complexes and catalysis for 2-vinylpyridine polymerization

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Journal of Rare Earths 2023年第3期41卷 381-387,I0003页

作者： Yinjun Wang Hao Jiang Huifei Wang Zehuai Mou Key laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province School of Material Science and Chemical EngineeringNingbo UniversityNingbo 315211China

The metathesis reaction between pyrrolidinyl-ethylene fluorenyl lithium salts with in situ prepared cationic rare-earth metal dialkyl species[Ln(CH_(2)sime_(3))_(2)(THF)_(x)][BPh_(4)]afford efficiently the corresponding constrained-geometry complexes L^(1)Ln(CH_(2)sime_(3))_(2)(L^(1)=FluCH_(2)CH_(2)NC_(4)H_(8),Ln=Y(1a),Lu(1b),Sc(1c))and L^(2)Ln(CH_(2)sime_(3))_(2)(L^(2)=(2,7-di-tert-butyl)FluCH_(2)CH_(2)NC_(4)H_(8),Ln=Y(2a),Lu(2b),Sc(2c))in good yields.All these complexes were characterized by NMR spectroscopy,and the solid-state molecular structure of yttrium complex 1a was defined with single-crystal X-ray diffraction analysis.The catalytic performance of these complexes towards 2-vinylpyridine polymerization was investigated,where these complexes alone can efficiently promote the polymerization of 2-vinylpyridine giving isotactic poly(2-vinylpyridine).Upon the activation with[Ph_(3)C][B(C_(6)F_(5))_(4)],the yttrium and lutetium complexes also afford isotactic poly(2-vinylpyridine),while the scandium complexes produce syndiotactic poly(2-vinylpyridine).

关键词： Rare-earth metal Constrained-geometry complex 2-Vinylpyridine Stereoselective polymerization

Dinitrogen Functionalization Affording Structurally Well-Defined Cobalt Diazenido Complexes

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CCS Chemistry 2022年第2期4卷 532-539页

作者： Mingdong Zhong Xianlu Cui Botao Wu Gao-Xiang Wang Wen-Xiong Zhang Junnian Wei Lili Zhao Zhenfeng Xi Beijing National laboratory for Molecular Sciences(BNLMS) Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of ChemistryPeking UniversityBeijing 100871 Institute of Advanced Synthesis School of Chemistry and Molecular EngineeringJiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing Tech UniversityNanjing 211816

Cobalt-bis(dinitrogen)complexes[LCo(N_(2))_(2)]−(3,4)with simple and commercially available bidentate phosphine ligands(L:Cy_(2)PCH_(2)CH_(2)PCy_(2))were synthesized and structurally characterized.Further N2 functionalization by treating the complex 3b with i Pr_(3)SiCl afforded the first structurally characterized cobalt diazenido complex 5.These complexes 3–5 were found to be effective catalysts for the transformation of N2 into N(sime_(3))_(3).The electronic structure of the cobalt diazenido complex 5 is supported by quantum computational calculations based on stateof-the-art energy decomposition analysis(EDA)in conjunction with the natural orbitals for chemical valence(NOCV)method.

关键词： bidentate phosphine ligand cobalt-bis(dinitrogen)complex cobalt diazenido complex dinitrogen functionalization dinitrogen silylation EDA-NOCV method

Lanthanide-catalyzed cyclocarbonylation and cyclothiocarbonylation: a facile synthesis of benzannulated 1,3-diheteroatom five- and six-membered heterocycles

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Science China Chemistry 2014年第8期57卷 1117-1125页

作者： JING YuFeng LIU RuiTing LIN YangHui ZHOU XiGeng Shanghai Key laboratory of Molecular Catalysis and Innovative Material Department of Chemistry Fudan University State Key laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry

La[N(sime3)2]3 proves to be an efficient catalyst system for the cyclocarbonylation of 1,2-disubstituted benzenes with isocyanates. In this approach, aryl/alkyl isocyanates react with o-phenylenediamine, o-aminophenol, o-aminothiophenol, catechols and anilines ortho-substituted by CH2NH2 and CONH2 to form, respectively, the corresponding benzimidazolones, benzoxazolones, benzothiazolones, benzodioxolones, 3,4-dihydroquinazolin-2(1H)-one, and quinazolinediones. These results represent the first example of lanthanide-catalyzed carbonylation. This methodology is also applicable for the preparation of various benzannulated 1,3-diheteroatom cyclic thioketones starting from aryl/alkyl isothiocyanates or CS2 in good to excellent yields. Based on the results of experiments performed using an o-aminobenzamido dianion lanthanide complex, a general mechanism, involving the tandem reaction of two lanthanide-ligand bonds with one heterocumulene molecule, is proposed as well.

关键词：稀土催化六元杂环化合物简便合成苯并咪唑酮邻氨基苯硫酚镧系元素异氰酸酯邻苯二胺