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Accuracy of tree mapping based on hand-held laser scanning comparing leaf-on and leaf-off conditions in mixed forests

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Journal of Forestry Research 2024年第5期35卷 14-25页

作者： Frederico Tupinambá-Simões Adrián Pascual Juan Guerra-Hernández cristóbal Ordóñez Tiago de Conto Felipe Bravo iuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIAValladolidSpain Department of Geographical Sciences University of MarylandCollege ParkMD 20742USA Forest Research Centre School of AgricultureUniversity of LisbonTapada da Ajuda1349‑017 LisbonPortugal

The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3D structures at high *** confirm the con-sistency in the retrieval of forest structural parameters using hand-held laser scanning(HLS),before operationalizing the method,confirming the data is *** analyzed the per-formance of tree-level mapping based on HLS under differ-ent phenology conditions on a mixed forest in western Spain comprising Pinus pinaster and two deciduous species,Alnus glutinosa and Quercus *** area was surveyed twice during the growing season(July 2022)and once in the deciduous season(February 2022)using several scan-ning *** reference data(418 trees,15 snags)was used to calibrate the HLS data and to assess the influence of phenology when converting 3D data into tree-level attrib-utes(DBH,height and volume).The HLS-based workflow was robust at isolating tree positions and recognizing stems despite changes in ***-six percent of all pairs matched below 65 *** DBH,phenology barely altered *** observed a strong agreement when comparing HLS-based tree height *** values exceeded 2 m when comparing height measurements,confirming height data should be carefully used as reference in remote sensing-based inventories,especially for deciduous *** volume was more precise for pines(r=0.95,and rela-tive RMSE=21.3–23.8%)compared to deciduous species(r=0.91–0.96,and relative RMSE=27.3–30.5%).HLS data and the forest structural complexity tool performed remark-ably,especially in tree positioning considering mixed forests and mixed phenology conditions.

关键词： Precision forestry Forest monitoring Mobile laser scanning Forest inventory

Dynamics of Polypropylene Chains in Their Binary Blends of Different Stereochemical Sequences Studied by Monte Carlo Simulations

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Chinese Journal of Polymer Science 2014年第5期32卷 640-650页

作者： Tanissara Pinijmontree Visit vao-soongnern Laboratory of Computational and Applied Polymer Science (LCAPS) School of Chemistry Institute of Science Suranaree University of Technology

The conformational and dynamic properties of polypropylene （PP） for both pure melts and blends with different chain tacticity were investigated by Monte Carlo simulation of isotactic （iPP）, atactic （aPP） and syndiotactic （sPP） polypropylenes. The simulation of coarse-grained PP models was performed on a high coordination lattice incorporating short- and long-range intramolecular interactions from the rotational isomeric state （RIS） model and Lennard-Jones （LJ） potential function of propane pairs, respectively. The dynamics of chains in binary PP/PP mixture were investigated with the composition of C150H302 with different chain taciticity. The diffusion rates of PP with different stereochemistry are generally in the order as： iPP 〉 aPP 〉〉 sPP. For PP/PP blends with 50：50 wt% binary mixtures, immiscibility was observed when sPP was introduced into the mixtures. The diffusion rate of iPP and aPP became slower after mixing, while sPP diffuses significantly faster in the binary mixtures. The mobility of PP chains depends on both intramolecular （molecular size and chain stiffness） and intermolecular （chain packing） interactions. The effect of intramolecular contribution is greater than that of intermolecular contribution for iPP and aPP chains in binary mixtures. For sPP chain, intermolecular interaction has greater influence on the dynamics than intramolecular contribution.

关键词： Binary blends of PP with different stereochemical sequences Dynamics Tacticity effect Monte Carlo Simulation.

Monte Carlo Simulation of the Structure of Mono-and Bidisperse Polyethylene Nanocomposites

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Chinese Journal of Polymer Science 2015年第2期33卷 275-283页

作者： Adisak Takhulee Rahmi Ozisik Visit vao-soongnern Laboratory of Computational and Applied Polymer Science School of Chemistry Institute of Science Suranaree University of Technology Department of Materials Science and Engineering Rensselaer Polytechnic Institute

The structure of bidisperse polyethylene（PE） nanocomposite mixtures of 50：50（by mole） of long and short chains of C160H322/C80H162 and C160H322/C40H82 filled with spherical nanoparticles were investigated by a coarse-grained, on lattice Monte Carlo method using rotational isomeric state theory for short-range and Lennard-Jones for long-range energetic interactions. Simulations were performed to evaluate the effect of wall-to-wall distance between fillers（D）, polymer-filler interaction（w） and polydispersity（number of short chains in the mixture） on the behavior of the long PE chains. The results indicate that long chain conformation statistics remain Gaussian regardless of the effects of confinement, interaction strength and polydispersity. The various long PE subchain structures（bridges, dangling ends, trains, and loops） are influenced strongly by confinement whereas monomer-filler interaction and polydispersity did not have any impact. In addition, the average number of subchain segments per filler in bidisperse PE nanocomposites decreased by about 50% compared to the nanocomposite system with monodisperse PE chains. The presence of short PE chains in the polymer matrix leads to a reduction of the repeat unit density of long PE chains at the interface suggesting that the interface is preferentially populated by short chains.

关键词： Monte Carlo simulation Polymer nanocomposites Bidisperse

Spring Inserts for the Intensification of the Heat Exchange Process during Boiling in Vertical Tubes--Optimization of Geometric Parameters

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Journal of Thermal Science 2018年第5期27卷 440-448页

作者： NIEZGODA-ZELASKO beata Faculty of Mechanical Engineering Institute of Thermal and Process Engineering Cracow University of Technology31-864 Cracow Poland

The paper presents new criteria for calculation of heat transfer coefficients and flow resistance during boiling inside vertical tubes with spring inserts, developed on the basis of own experimental research. Calculations of the geometric parameters of the spring insert were carried out using the Nelder-Mead optimization method for various optimization criteria(maximizing the increase ratios for heat transfer coefficient and flow resistance, minimizing entropy, own optimization criterion). The results of optimization calculations were verified by the optimization procedures available in Statistica.

关键词： boiling heat transfer flow resistance spring inserts optimization

Modeling of Thermal Properties of Thermal Insulation Layered with Transparent,Opaque and Reflective Film

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Journal of Thermal Science 2018年第5期27卷 463-469页

作者： GRABOWSKA beata KASPERSKI Jacek Faculty of Mechanical and Power Engineering Wroclaw University of Science and TechnologyWroclaw 50-370 Poland

The popular and effective food preservation technology based on refrigeration is not sufficient for high-quality products while undergoing logistic operations(transport and retail). One of the basic factors that affects the quality of chilled and frozen food products during storage and transport is packaging. A protective function of packaging strongly depends on the material used and its composition. There are different kinds of thermal insulation used for food packaging. One of them, proposed by the authors is a multilayer structure of insulation made of rectangular air cells. The insulation can be prepared by means of plastic film featuring various properties. The paper presents how to improve an effective material designed for food freezing and transport aiming to enhance its thermal resistance through the application of different transparency, reflectivity and emissivity of the film. Mathematical model based on heat exchange equations, including conduction, convection and radiation throughout a number of parallel internal sheets of film of multilayer structures was proposed. Thermal properties depending on different transparency, reflectivity and emissivity of the film were analyzed. The model was verified experimentally showing its compatibility and obtaining a significant influence of thermal resistance according to the type of film used to make air structures, the number and thickness of its layers as well as the gaps between internal folds. For multi-layer insulation designed for the insulation of packed frozen food in the shape of a rectangle, it was recommended to apply film transmittance as small as possible for the internal parts of the structure.

关键词： frozen food heat transfer transparency reflectance thermal isolation food package

Computer simulation of the coagulation of suspended solids——The applicability of the Müller–Smoluchowski theory

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Journal of Environmental Sciences 2016年第6期28卷 197-203页

作者： Regina Wardzynska beata Zaleska-Chróst Department of Chemistry University of Warmia and Mazury in Olsztyn

The results of studies carried out using a computer programme simulating the coagulation of suspensions containing spherical sol particles and spherical coagulant particles are *** influence of the degree of dispersion of the system on the coagulation reaction kinetics was investigated. The obtained results of kinetic studies were tested in the light of classical Müller–Smoluchowski equations. The influence of the physical properties of the coagulant,such as size, density and mass, on the coagulation rate was tested. It was found that within the range described in this paper, the rate of the simulated coagulation process fulfils both the kinetic equation of a first-order reaction, and the kinetic equation of a second-order *** the tested range, a significant influence of the mass and size of the coagulant on the coagulation rate was ascertained. The kinetic Müller–Smoluchowski dependence is fulfilled in a broader range of the degree of dispersion, when the coagulant particle mass and the sol particle mass are equal. When the particle mass increases with an increase in the particle radius, the coagulation rate increases faster that it would result from the Müller＇s dependence.

关键词： Aggregation Computer simulation Coagulation rate Sol

The Graft Thickness in Descemet Stripping Automated Endothelial Keratoplasty:What Is the Importance to the Final Visual Outcome?

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Open Journal of Ophthalmology 2017年第3期7卷 167-175页

作者： Diana cristóvao Ana Fonseca Nuno Alves Vítor Maduro Joao Feijao Pedro Candelária Instituto de Oftalmologia Dr.Gama Pinto(IOGP) LisbonPortugal Centro Hospitalar de Lisboa Central(CHLC) LisbonPortugal

Introduction: Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) is currently considered the procedure of choice for the treatment of endothelial dysfunctions. Despite DSAEK being a promising procedure to improve visual acuity (VA), the ideal graft thickness donor still remains under discussion. Purpose: To analyze the influence of graft thickness on postoperative VA and complications in DSAEK surgery. Methods: Retrospective study of 112 eyes that underwent DSAEK surgery. Donor grafts were obtained by dissection with automatic microkeratome, using different head sizes. Central corneal thickness (CCT) of donor corneas before dissection was measured by ultrasound pachymetry. The choice of the cutting depth was based on CCT measurements and the final desired residual corneal thickness, corresponding to the estimated donor graft thickness (EDGT). The eyes were divided into 3 groups, depending on the EDGT: 200 μm (Group 3). Intraoperative, postoperative complications and the best corrected visual acuity (BCVA) at 6 months postoperatively were evaluated, comparing these 3 groups. Results: The average EDGT was 164 ± 10 μm in Group 1188 ± 7 μm in Group 2 and 234 ± 30 μm in Group 3. At 6 months postoperative the average BCVA was significantly better in Group 1 (BCVA: 0.74 ± 0.20), compared to Group 2 (BCVA: 0.54 ± 0.20) and Group 3 (BCVA: 0.39 ± 0.18). Intraoperative and postoperative complications included: graft perforation during cutting (0.9% of cases), graft rejection (3.6%), primary graft failure (4.5%), and graft detachment (3.6%). Its distribution was uniform between the 3 groups. Conclusion: The study proves that DSAEK is an effective surgical technique for the treatment of endothelial dysfunction, demonstrating that the use of thinner grafts (EDGT < 180 μm) can improve the final visual outcome, with a significant improvement on BCVA, without increasing the risk of complications.

关键词： DSAEK Graft Thickness Visual Acuity Complications

Hepatectomy for bile duct injuries: When is it necessary?

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World Journal of Gastroenterology 2013年第38期19卷 6348-6352页

作者： beata Jablońska Department of Digestive Tract Surgery University Hospital of the Medical University of Silesia40-752 KatowicePoland

Iatrogenic bile duct injuries(IBDI)are still a challenge for *** most frequently,they are caused by laparoscopic cholecystectomy which is one of the commonest surgical procedure in the *** techniques are recommended as initial treatment of *** endoscopic treatment is not effective,surgery is *** surgical biliary reconstructions are performed in most patients in ***-Y hepaticojejunostomy is the commonest biliary reconstruction for *** some patients with complex IBDI,hepatectomy is ***,Liet al analyzed the factors that had led to hepatectomy for patients with IBDI after laparoscopic cholecystectomy(LC).Authors concluded that hepatectomy might be necessary to manage early or late complications after *** study showed that proximal IBDI(involving hepatic confluence)and IBDI associated with vascular injuries were the two independent risk factors of hepatectomy in this *** distinguished two main groups of patients that require liver resection in IBDI:those with an injury-induced liver necrosis necessitating early intervention,and those in whom liver resection is indicated for treatment of liver atrophy following long-term *** this commentary,indications for hepatectomy in patients with IBDI are *** biliovascular injuries as indications for hepatectomy are ***-and long-term results in patients following liver resection for IBDI are also *** is not a standard procedure in surgical treatment of IBDI,but in some complex injuries it should be considered.

关键词： Hepatectomy Bile duct injury Cholecystectomy Laparoscopic cholecystectomy

Biliary cysts:Etiology,diagnosis and management

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World Journal of Gastroenterology 2012年第35期18卷 4801-4810页

作者： beata Jabońska Department of Digestive Tract Surgery University Hospital of the Medical University of Silesia

Biliary cysts(BC) are rare dilatations of different parts of a biliary *** account for approximately 1% of all benign biliary *** occur the most frequently in Asian and female *** are an important problem for pediatricians,gastroenterologists,radiologists and *** presentation and management depend on the BC *** is the most serious and dangerous BC *** other complications associated with BC involve cholelithiasis and hepatolithiasis,cholangitis,acute and chronic pancreatitis,portal hypertension,liver fibrosis and secondary liver cirrhosis and spontaneous cyst *** BC classifications have been described in the *** classification dividing BC into five types is the most useful in clinical *** early diagnosis and proper treatment are very important,because BC are associated with a risk of carcinogenesis.A malignancy risk increases with the *** investigations(ultrasonography,computed tomography,endoscopic retrograde cholangiopancreatography and magnetic resonance cholangiopancreatography) play an important role in BC ***,prenatal diagnosis using ultrasonography is *** allows to differentiate biliary disorders in fetals and to perform the early surgical treatment that improves *** most patients,total cyst excision with Roux-Y hepaticojejunostomy is the treatment of *** treat-ment of BC is associated with high success rate and low morbidity and *** early treatment is associated with a lower number of *** following BC surgery require permanent and careful postoperative observation using laboratory and imaging investigations because of possibility of biliary anastomosis stricture and biliary cancer in tissue remnant.

关键词： Biliary cysts Biliary drainage Hepaticojeju-nostomy