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Estimating costs of salvage logging for large-scale burned forest lands: A case study on Turkey's Mediterranean coast

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Journal of Forestry Research 2021年第5期32卷 1899-1909页

作者： neşe Gülci Faculty of Forestry Kahramanmaras Sutcu Imam University46100 KahramanmarasTurkey

Different forest fires causing different degrees of effects occur in fire-sensitive forests due to various reasons such as climate *** as well as harmful aspects of forest fires are a multi-disciplinary research *** information systems(GIS)and remote sensing(RS)methods offer a number of benefits for researchers and operators in the field of forest fire *** present study analyses timber pricing based on forest contractor demands of post-salvage logging *** effect of timber obtained from compartment units on producers’pricing policy was *** forest fire area(2500 ha)located in Antalya in Turkey was selected as the main study *** parameters(aspect,slope and slope position),stand types(diameter class and crown closure),and burn severity were analyzed together using GIS and R software packages.A multi-linear regression model(R^(2)=0.752)demonstrated that factors that had the most impact on pricing were slope position,aspect,stand age,crown closure and burn *** model can be used to estimate salvage logging prices in Calabrian pine(Pinus brutia Ten.)stands with similar *** administrators and contractors may readily address the unit price of timber by estimating approximate costs in a given forest area for which they are going to *** will help reduce operational planning times of harvesting procedures in burned stands.

关键词： Timber extraction Forest fires Stumpage sale Cost estimation Sustainability Crown fire

Study and Design of a DC/AC Energy Converter for PV System Connected to the Grid Using Harmonic Selected Eliminated (HSE) Approach

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Open Journal of Applied Sciences 2022年第3期12卷 301-316页

作者： Dominique Bonkoungou Éric Korsaga Toussaint Guingané sosthène Tassembédo Zacharie Koalaga François Zougmoré Laboratory of Materials and Environment (LA.M.E) University of Joseph KI-Zerbo Ouagadougou Burkina Faso University of Thomas Sankara (UTS) Ouagadougou Burkina Faso

Nowadays, distributing network-connected photovoltaic (PV) systems are expanded by merging a PV system and a Direct Current (DC)/Alternating Current (AC) energy converter. DC/AC conversion of PV energy is in great demand for AC applications. The supply of electrical machines and transfer energy to the distribution network is a typical case. In this work, we study and design a DC/AC energy converter using harmonic selective eliminated (HSE) method. To this end, we have combined two power stages connected in derivation. Each power stage is constituted of transistors and transformers. The connection by switching of the two rectangular waves, delivered by each of the stages, makes it possible to create a quasi-sinusoidal output voltage of the inverter. Mathematical equations based on the current-voltage characteristics of the inverter have been developed. The simulation model was validated using experimental data from a 25.2 kWp grid-coupled (PV) system, connected to Gridfit type inverters. The data were exported and implemented in programming software. A good agreement was observed and this shows all the robustness and the technical performances of the energy converter device. It emerges from this analysis that the inverter output voltage and the phase angle thus simulated are very important to control in order to orientate the transfer of the power flow from the continuous cell to cell to the alternating part. Simulated and field-testing results also show that increases in the value of the modulation factor (m) for low power output are highly significant. This study is an important tool for DC/AC inverter designers during initial planning stages. A short presentation of the design model of the inverter has been proposed in this article.

关键词： Inverter Modulation Index Transistors Power Stage Harmonic Selective Eliminated Photovoltaic (PV) System

Formally Analyzing Expected Time Complexity of Algorithms Using Theorem Proving

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Journal of Computer Science & Technology 2010年第6期25卷 1305-1320页

作者： Osman Hasan Sofiène Tahar Department of Electrical and Computer Engineering Concordia University

Probabilistic techniques are widely used in the analysis of algorithms to estimate the computational complexity of algorithms or a computational ***,such analyses are performed using paper-and-pencil proofs and the results are sometimes validated using simulation *** techniques are informal and thus may result in an inaccurate *** this paper,we propose a formal technique for analyzing the expected time complexity of algorithms using higher-order-logic theorem *** approach calls for mathematically modeling the algorithm along with its inputs,using indicator random variables,in higher-order *** model is then used to formally reason about the expected time complexity of the underlying algorithm in a theorem *** paper includes the higher-order-logic formalization of indicator random variables,which are fundamental to the proposed *** order to illustrate the practical effiectiveness and utilization of the proposed infrastructure,the paper also includes the analysis of algorithms for three well-known problems,i.e.,the hat-check problem,the birthday paradox and the hiring problem.

关键词： formal method higher-order logic probability theory theorem proving birthday paradox hat-check problem hiring problem

Ultrastructural Pathologic Observation on the Gut-Associated Lymphoid Tissues of Sacculus Rotundus of Rabbits Infected with Rabbit Haemorrhagic Disease Virus

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Agricultural Sciences in China 2003年第4期2卷 446-453页

作者： SHERui-ping YANGHan-chun JIAJun-zheng LIUHai-hong mayi-xin ItakuraC CollegeofAnimalMedicine ChinaAgriculturalUniversityBeijing100094P.R.China VeterinaryFaculty HokkaidoUniversitySapttoro062Japan

Ultrastructural pathological changes in the gut-associated lymphoid tissues of sacculus rotundus (SR) of rabbits infected with rabbit haemorrhagic disease virus (RHDV) were first observed. There were numerous holes at the luminal and basement membrane surfaces of the dome epithelium (DE), consistently accompanied by necrosis of lymphocytes and M-cells, and pronounced depletion of lymphocytes in the domes and follicles, decrease of DE complex with formation of pseudomembranous structure on the surface of the dome epithelium. A specific finding in lymphocytes and macrophages was that severe destruction detraction of the membrane of rough endoplasmic reticulum(RER) was accompanied by conspicious increase of solitary, ribo-some-like particles in the cytoplasm, with appearances of intranuclear particles and intranuclear inclusions. It was found that there were many round and dense virion-like particles, with 26 nm in diameter, in the nuclei and cytoplasm of lymphoctes, plasma cells, macrophages and fibroblasts, or in degenerated cells and cellular debris. At the same time, another round virion-like particles about 34 nm in diameter were also seen in the cytoplasm of some cells and interstitium. The results indicated that the appearances of the ribosome-like particles, virion-like particles and inclusion bodies were related to the replication and assembly of RHDV. The present observations suggested that DE of sacculus rotundus could be a open pathway and a transporting route for the entry of antigens into hosts. While the antigen is profoundly deleterious, DE may be as a closed portal or a barrier preventing the foreign antigenic materials from invading.

关键词： Succulus rotundus Rabbit haemorrhagic disease M-cells Dome epithelium Ultrastructural pathological changes

SYNTHESIS OF SOLUBLE POLY(3,4-DIHYDROXY-o-TOLYLEne):REDOX POLYMER

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Chinese Journal of Polymer Science 2006年第1期24卷 41-46页

作者： Sad Moulay Fatima M'zyène Laboratoire de Chimie-Physique Moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Département de Chimie Industrielle Université de BlidaRoute de SoumèaB.P.270Blida 09000Algeria. Laboratoire de Chimie-Physique Moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Département de Chimie Industrielle Université de BlidaRoute de SoumaB.P.270Blida 09000Algeria.

Conventional chloromethylation, paraformaldehyde/hydrogen chloride in acetic acid medium, was applied to 1,2- dimethoxybenzene. Chloroform-soluble poly（3,4-dimethoxy-o-tolylene） was obtained with an intrinsic viscosity of 0.034 dL g^-1. The polymer was evaluated as a condensation redox polymer precursor formed by a Friedel-Crafts reaction. Cleavage of the methoxy groups present in this polymer resulted in poly（3,4-dihydroxy-o-tolylene） which manifested a great air-oxidation resistance. The redox property of the latter polymer was found to be 1017 mV by potentiometric titration with 0.05 N ceric ammonium nitrate at 25℃. This midpotential was compared to that of catechol, a monomeric analogue, under the same titration conditions.

关键词： Poly(3,4-dimethoxy-o-tolylene) Poly(3,4-dihydroxy-o-tolylene) Redox polymer.

Formal Reasoning About Finite-State Discrete-Time Markov Chains in HOL

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Journal of Computer Science & Technology 2013年第2期28卷 217-231页

作者： Liya Liu Osman Hasan Sofiène Tahar Department of Electrical and Computer Engineering Concordia University

Markov chains are extensively used in modeling different aspects of engineering and scientific systems, such as performance of algorithms and reliability of systems. Different techniques have been developed for analyzing Markovian models, for example, Markov Chain Monte Carlo based simulation, Markov Analyzer, and more recently probabilistic model- checking. However, these techniques either do not guarantee accurate analysis or are not scalable. Higher-order-logic theorem proving is a formal method that has the ability to overcome the above mentioned limitations. However, it is not mature enough to handle all sorts of Markovian models. In this paper, we propose a formalization of Discrete-Time Markov Chain （DTMC） that facilitates formal reasoning about time-homogeneous finite-state discrete-time Markov chain. In particular, we provide a formal verification on some of its important properties, such as joint probabilities, Chapman-Kolmogorov equation, reversibility property, using higher-order logic. To demonstrate the usefulness of our work, we analyze two applications： a simplified binary communication channel and the Automatic Mail Quality Measurement protocol.

关键词： discrete-time Markov chain higher-order logic probability theory theorem prover

Direct Ni Electroless Metallization of Poly(etherimide) without Using Palladium as a Catalyst

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材料热处理学报 2004年第05B期25卷 1106-1111页

作者： Marlène Charbonnier Maurice Romand Yves Goepfert Laboratoire de Sciences et Ingenierie des Surfaces Universite Claude Bernard - Lyon 1 69622 Villeurbanne Cedex FranceLaboratoire de Sciences et Ingenierie des Surfaces Universite Claude Bernard - Lyon 1 69622 Villeurbanne Cedex FranceUMR 5180 des Sciences Analytiques Universite Claude Bernard - Lyon 1 69622 Villeurbanne Cedex France

Nickel or copper electroless metallization of polymers needs the grafting of a catalyst (palladium in the Pd(0) oxidation state) on the substrate surface to be coated. Our previous works on this topic [1-5] have allowed to develop a simple, tin-free method to attach Pd(+2) species from a palladium chloride (PdCl2) solution on any insulating surface and subsequently to reduce them, in the wet way, into the Pd(0) oxidation state. This Pd(0) state of the catalyst allows an instantaneous initiation of the Ni or Cu deposit by immersion in a plating bath. As palladium is an expensive chemical, it appears interesting to replace it by Ni(0) or Cu(0) species which are catalysts of their own ion reduction. Concerning the direct Ni electroless plating, the polymer surface (PI) was made catalytic for the electroless process by deposition (spin- coating or dipping) of an ultra-thin film of an organic nickel salt in an alcoholic solution. The chemical reduction of this salt, checked by XPS, was performed by chemical or photochemical ways and by plasma. Under these conditions, the initiation, by autocatalysis, of the Ni film deposition in an industrial plating bath was immediate i.e. without any initiation time. The film obtained was homogeneous, dense, bright, well-adhering up to thicknesses reaching

关键词：镍非电金属喷镀等离子处理 XPS 聚酰亚胺

Assessment of Liver Fibrosis in HBsAg-negative and Anti HBc Positive Patients

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Open Journal of Gastroenterology 2024年第10期14卷 331-339页

作者： Kounpiélimé sosthène Somda Aboubacar Coulibaly Oyétoundé Taofick Amanda Sandrine Marie Odile Soudre Lawagoulé Joseph Emile Ky Christiane Bere Arsène Roger Sombie Department of Hepato-Gastroenterology Yalgado Ouedraogo University Hospital (CHU-YO) Ouagadougou Burkina Faso Department of Medicine University Joseph KI-ZERBO Ouagadougou Burkina Faso

Background: Surface antigen (HBsAg) is the mean marker of hepatitis B virus infection. During the course of the infection, some patients lose the HBsAg and only the presence of anti-HBc antibody indicates previous contact with the virus. Among these patients, some have detectable viral load (occult infection) but most without viral replication. There is no guideline regarding these patients. The aim of this study was to assess hepatic fibrosis in patients with only the hepatitis B virus contact marker “total anti-HBc”. Patients and methods: it was a descriptive and analytical cross-sectional study, conducted in three private hospitals from January to August 2022. Were included HBsAg-negative and HBc-positive patients, consulting in Gastroenterology departments. Noninvasive methods (APRI, FIB-4 and FIBROSCAN) were used to evaluate liver stiffness because of their easy accessibility and low-cost. The hepatic fibrosis was considered significant when the score determined by APRI, FIB-4 and FIBROSCAN® tests was respectively greater than 1.5;2.67 and 8 kPa corresponding to fibrosis level 2 (F2). Results: A total of 63 HBsAg-negative/total HBcAg-positive patients were included. The mean age was 49.9 ± 13.4 years. The male/female sex ratio was 1.78. Of the 63 patients, 19 had significant liver fibrosis (30.1%) among which 9 patients had HCC. The FIB-4 score outperformed the APRI score in assessing liver fibrosis, with a sensitivity of 84.2%, a specificity of 100% and a negative predictive value of 93.6%. In univariate analysis, there was a significant association between the occurrence of significant liver fibrosis and age over 40 years, dyslipidaemia, obesity, alcohol consumption, smoking, herbal medicine, negative anti-HBs immunological status and detectable viral load. Conclusion: Our study revealed a high prevalence of significant to severe hepatic fibrosis in anti-HBc positive patients. In most of the cases, the fibrosis was severe. Progression to HCC has also been pos

关键词： Anti HBc Positives Liver Fibrosis Sub-Saharan Hepatitis B Virus

A new Approach to Diagnosing Signals from Multivariate EWMA Control Chart

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International Journal of Plant Engineering and Management 2003年第4期8卷 193-198页

作者： mayi-zhong ZHAOFeng-yu BusinessandManagementSchool BeijingUniversityofAeronauticsandAstronauticsBei3＂ing100083P.R.China ZhengzhouInstituteofAeronautics Zhengzhou450005P.R.China

Since Lowry et al. [1992] proposed a multivariate version of theexponentially weighted moving average (EWMA) control chart, the multivariate EWMA control chart hasbecome more and more popular in monitoring production processes, especially in chemical processes.A major advantage of multivariate EWMA statistics is that it is sensitive to small and moderateshifts in the mean vector. However, when a multivariate EWMA chart issues a signal, it is difficultto identify which variable or set of variables is out of control. In this paper, we introduce anew approach to diagnosing signals from a multivariate EWMA control chart. The implementationprocedure is that when the multivariate EWMA control chart issues a signal, we adopt a univariatediagnostic procedure to identify the variables or/and the principal components that caused thesignal.

关键词： multivariate process control EWMA special cause identification diagnosticprocedure