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A basal area increment model for individual trees in mixed continuous cover forests in Iranian Caspian forests

Journal of Forestry Research 2020年第1期31卷 99-106页

作者： Nishtman Hatami peter lohmander Mohammad Hadi Moayeri Soleiman Mohammadi Limaei Department of Forestry Faculty of Natural ResourcesGorgan University of Agricultural Sciences and Natural ResourcesP.O.Box 386mGorganIran Optimal Solutions in Cooperation with Linnaeus University Va¨xjo¨Sweden Department of Forestry Faculty of Natural ResourcesUniversity of GuilanP.O.Box 1144Sowmeh SaraIran

The aim of this study was to develop and test a new basal area growth model in mixed species continuous cover forests in northern *** 421 core samples from 6 main species in the forest area to develop our growth *** each plot,we measured variables such as total tree height(m),diameter at breast height(DBH)(cm)and basal area of larger trees as cumulative basal areas of trees(GCUM)ofDBH[5 *** empirical data were analyzed using regression *** was a statistically significant nonlinear function between the annual basal area increment,as the dependent variable,and the basal area of the individual trees and competition as explanatory *** area from the largest trees,was circular plot with area of 0.1 *** was estimated for trees of DBH>5 ***,we investigated the dependencies of diameter growth of different species on stand density at different levels of competition,and diameter development of individual trees through *** results indicate that competition caused by larger neighborhood trees has a negative effect on *** addition,the maximum diameter increment is affected by competition ***,the maximum diameter increment of species occurs when the trees are about 35–40 cm in dense-forest(40 to 0 m^2 per ha)and when the trees are about 60 to 70 cm in very dense forest(60 to 0 m^2 per ha)which is more likely to Caspian natural forests with high level density due to uneven-aged composition of stands.

关键词： Individual-tree model Iranian Caspian forests Continuous cover forestry Mixed stands Uneven-aged management

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Quantitative and financial evaluation of non-timber forest products(case study:Zemkan basin forests,West of Iran)

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Journal of Forestry Research 2017年第2期28卷 371-379页

作者： Sohrab Moradi Soleiman Mohammadi Limaei peter lohmander Mehrdad Khanmohammadi Faculty of Agricultural Sciences Payame Noor UniversityTehranIran University of Guilan Sowmeh SaraIran Department of Forestry Faculty of Natural ResourcesUniversity of GuilanSowmeh SaraIran Department of Forest Economics Faculty of Forest SciencesSwedish University of Agricultural SciencesUmeaSweden Department of Environmental Sciences Faculty of Natural ResourcesUniversity of GuilanSowmeh SaraIran

Although Zagros forests in western Iran lack industrial timber value due to the severe climate and socioeconomics problems, non-timber products are of great value and importance due to their high economic potential and also their potential to improve the welfare of forestdwelling and forest-fringe villagers. This study was done in the forests of the Zemkan basin, an important part of central Zagros forests, Iran, to recognize the non-timber forest products（NTFPS）, investigate their potential economic value and role in people＇s livelihood. Data, collected using forest cruising, participatory observations, interviews with indigenous and local persons and experts, identified wild pistachio resin, wild pistachio fruit, oak fruit and oak syrup（Shokeh manna） among the non-timber products in this basin with total potential harvestable NTFPs of 77.16,771.602, 13248.68, and 1324.868 tons per year,respectively. The economic rent from NTFPs is 33 US$/ha/year and its total expected values with consideration of real interest rate when the exploiter invests the capital in the bank（6.4 %） and when money is borrowed from the bank to execute the incorporated projects（8.4 %） are $516/ha and $393/ha, respectively. Furthermore, families＇ economic share from potential profit of NTFPs is annually$601 per household. In addition wild pistachio resin has the highest share of the total potential profit of NTFPs and its equal to 51 % of the total of potential profit of ***, it is suggested that decisions be made to increase the infrastructure and strengthen the local selling market to enhance the cash income from NTFPs. Forest participatory management practices are suggested to organize and improve traditional use of the forests.

关键词： timber forests profit resin annually recognize fringe income household execute

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Estimation of a basal area growth model for individual trees in uneven-aged Caspian mixed species forests

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Journal of Forestry Research 2018年第5期29卷 1205-1214页

作者： Zohreh Mohammadi Soleiman Mohammadi Limaei peter lohmander Leif Olsson Department of Forestry Faculty of Natural ResourcesUniversity of Guilan P.O. Box 1144 Sowmeh Sara Iran Optimal Solutions in Cooperation with Linnaeus University Umea Sweden Department of Information Systems and Technology Facultyof Sciences Technology and Media Mid Sweden UniversitySundsvall Sweden

The aim of this study was to estimate a basal area growth model for individual trees in uneven-aged Caspian forests.A survey was conducted in order to find a natural forest without any harvesting activities,a so called ＇untouched forest＇ and an area was selected from the Iranian Caspian *** sample plots in the same aspect and of the same forest type were *** each plot,total tree height,diameter at breast height,distance of neighbor trees and azimuth were *** trees were selected and drilled with increment borer to determine the increment *** analysis was used to estimate the growth *** show that,for individual trees,there is a significant nonlinear relationship between the annual basal area increment,as the dependent variable,and the basal *** results also show that the basal area of competing trees has a positive influence on *** the increment is higher with more competing neighboring trees is possibly because plots with higher volume per hectare and more competition,most likely also have higher site index or better soil or better site productivity than the plot with lower volume per hectare.

关键词： Basal area increment Diameter growth Regression analysis Caspian forests

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The effect of climate factors on the size of forest wildfires(case study:Prague-East district,Czech Republic)

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Journal of Forestry Research 2022年第4期33卷 1291-1300页

作者： Zohreh Mohammadi peter lohmander Jan Kašpar Roman Berčák Jaroslav Holuša Robert Marušák Faculty of Forestry and Wood Sciences Czech University of Life Sciences PragueKamýcká12916500 Praha-SuchdolCzech Republic Optimal Solutions in Cooperation with Linnaeus University UmeaSweden

This paper presents a new approach to identifying the climate variables that influence the size of the area burned by forest *** linear regression was used in combination with nonlinear variable transformations to determine relevant nonlinear forest wildfire size *** from the Prague-East District of the Czech Republic was used for model *** burned forest area was hypothesized as a function of water vapor pressure,air temperature and wind *** speed was added to enhance predictions of the size of forest wildfires,and further improvements to the utility of prediction methods were added to the regression *** results show that if the air temperature increases,it may contain less water and the fuel will become *** size of the burned area then *** the relative humidity in the air increases and the wind speed decreases,the size of the burned area is *** model suggests that changes in the climate factors caused by ongoing climate change could cause significant changes in the size of wildfire in forests.

关键词： Climatic variables Burned forest area Climate change Multiple linear regression

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风险状态下混交林最优经营决策(英文)

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林业科学 2009年第11期45卷 83-89页

作者：鲁法典 peter lohmander 山东农业大学林学院泰安271018 瑞典农业科技大学林业经济系 Umea 90183

不同树种对来自不同种类的真菌、昆虫和脊椎动物的伤害反应敏感度不同,而不同树种生产的林产品价格也随时间而不断变化。混交林为后继的适应性决策提供了宝贵的选择。本文建立一个基于麋鹿危害和价格风险的适应性优化模型,用于确定挪威... 详细信息

不同树种对来自不同种类的真菌、昆虫和脊椎动物的伤害反应敏感度不同,而不同树种生产的林产品价格也随时间而不断变化。混交林为后继的适应性决策提供了宝贵的选择。本文建立一个基于麋鹿危害和价格风险的适应性优化模型,用于确定挪威云杉和欧洲赤松混交林的初始混交比例以便达到预测净现值的最大化。结果表明,即使在不考虑风险的情况下,由于混交效益,混交林也比纯欧洲赤松林优越。但考虑麋鹿危害时,混交林的优势将提高5%。如果加入瑞典森林法规定的最低林木株数要求,这种优势将提高24%。当考虑价格风险和选择性间伐时,混交林的优势进一步提高6%。

关键词：森林经营决策不确定性风险适应性优化

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An Interview with peter Deadman—Acupuncture Pioneer and Founder of The Journal of Chinese Medicine

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Chinese Medicine and Culture 2024年第1期7卷 19-28页

作者： Ioannis Solos Charles Buck peter Deadman Saint George Clinic and Research Institute Scottsdale 85251the United States of America Northern College of Acupuncture Micklegate YO16LJthe United Kingdom British Acupuncture Council London W129HQthe United Kingdom The Register of Chinese Herbal Medicine London WC1N 3GSthe United Kingdom

This interview was conducted on August 21st, 2022 by Charles Buck and Ioannis Solos. peter Deadman has worked in the field of health promotion for 50 years. He co-founded Infinity Foods(an organic and natural foods workers co-op) in 1971, followed by the Brighton Natural Health Centre-a charity dedicated to teaching ways to improve personal, community and planetary health and wellbeing. He qualified as an acupuncturist in 1978 and in Chinese herbal medicine in 1990. He founded The Journal of Chinese Medicine(UK) in 1979(Fig. 1), and co-authored A Manual of Acupuncture(published in 1998). He is the author of Live Well Live Long: Teachings from the Chinese Nourishment of Life Tradition. He has taught Chinese medicine and health promotion internationally for decades and is a dedicated practitioner and teacher of Qi Gong(气功).

关键词： Acupuncture Medicine herbal

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Experimental investigation on slip conditions during thread rolling with flat dies

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Friction 2024年第1期12卷 136-143页

作者： Stefan VOLZ peter GROCHE Institute for Production Engineering and Forming Machines Technical University DarmstadtOtto-Berndt Straße 2Darmstadt 64287Germany

The process design of flat die rolling operations can be a tedious and costly process due to the challenges posed by small process *** this work,an effort is made to closely investigate and understand the process limits caused by excessive slippage of the *** measurements are carried out to capture the characteristics of excessive slippage and the influence of the stroke rate and the tribological system on this process *** differences in slippage were observed,depending on the tribological *** systems with polymer based lubricants showed excessive slippage at low stroke rates,systems using oil or no lubricant endured higher stroke rates before process limits were *** optical measurements revealed three major forms of slippage:successful rolling without slippage,failure due to excessive slippage at process start,and failure due to excessive slippage at around one workpiece rotation.

关键词： rolling incremental forming thread rolling slippage profile rolling

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Skeletal muscle as a molecular and cellular biomarker of disease progression in amyotrophic lateral sclerosis:a narrative review

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Neural Regeneration Research 2024年第4期19卷 747-753页

作者： peter H.King Department of Neurology and Center for Neurodegeneration and Experimental Therapeutics The University of Alabama at BirminghamBirminghamALUSA Birmingham Veterans Affairs Medical Center BirminghamALUSA

Amyotrophic lateral sclerosis is a fatal multisystemic neurodegenerative disease with motor neurons being a primary *** progressive weakness is a hallmark feature of amyotrophic lateral sclerosis,there is considerable heterogeneity,including clinical presentation,progression,and the underlying triggers for disease *** on longitudinal studies with families harboring amyotrophic lateral sclerosis-associated gene mutations,it has become apparent that overt disease is preceded by a prodromal phase,possibly in years,where compensatory mechanisms delay symptom *** 85-90%of amyotrophic lateral sclerosis is sporadic,there is a strong need for identifying biomarkers that can detect this prodromal phase as motor neurons have limited capacity for *** Food and Drug Administration-approved therapies work by slowing the degenerative process and are most effective early in the *** muscle,including the neuromuscular junction,manifests abnormalities at the earliest stages of the disease,before motor neuron loss,making it a promising source for identifying biomarkers of the prodromal *** accessibility of muscle through biopsy provides a lens into the distal motor system at earlier stages and in real *** advent of“omics”technology has led to the identification of numerous dysregulated molecules in amyotrophic lateral sclerosis muscle,ranging from coding and non-coding RNAs to proteins and *** technology has opened the door for identifying biomarkers of disease activity and providing insight into disease mechanisms.A major challenge is correlating the myriad of dysregulated molecules with clinical or histological progression and understanding their relevance to presymptomatic phases of *** are two major goals of this *** first is to summarize some of the biomarkers identified in human amyotrophic lateral sclerosis muscle that have a clinicopathological correlation with disease activi

关键词： amyotrophic lateral sclerosis biomarkers clinicopathological correlation disease progression muscle biomarkers neurogenic atrophy neuromuscular junction non-coding RNAs presymptomatic stages skeletal muscle SOD1G93A mouse model

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A product version of the Hilton-Milner-Frankl theorem

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Science China Mathematics 2024年第2期67卷 455-474页

作者： peter Frankl Jian Wang Alfréd Rényi Institute of Mathematics Hungarian Academy of SciencesBudapest H-1053Hungary Department of Mathematics Taiyuan University of TechnologyTaiyuan 030024China

Two families F and G of k-subsets of {1, 2,..., n} are called non-trivial cross t-intersecting if|F ∩ G|≥t for all F ∈ F, G ∈ G and | ∩ {F : F ∈ F}| < t, | ∩ {G : G ∈ G}| < t. In the present paper,we determine the maximum product of the sizes of two non-trivial cross t-intersecting families of k-subsets of{1, 2,..., n} for n≥4(t + 2)2k2, k≥5, which is a product version of the Hilton-Milner-Frankl theorem.

关键词： extremal set theory cross t-intersecting family product version non-trivial

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A Population Dynamics Approach to the Distribution of Space Debris in Low Earth Orbit

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Communications on Applied Mathematics and Computation 2024年第1期6卷 340-353页

作者： John Jurkiewicz peter Hinow Department of Mathematical Sciences University of Wisconsin-MilwaukeeMilwaukeeWI53201USA

The presence of the debris in the Earth’s orbit poses a significant risk to human activity in outer *** debris population continues to grow due to ground launches,the loss of external parts from space ships,and uncontrollable collisions between objects.A computationally feasible continuum model for the growth of the debris population and its spatial distribution is therefore *** we propose a diffusion-collision model for the evolution of the debris density in the low-Earth orbit and its dependence on the ground-launch *** parametrize this model and test it against data from publicly available object catalogs to examine timescales for the uncontrolled ***,we consider sensible launch policies and cleanup strategies and how they reduce the future risk of collisions with active satellites or space ships.

关键词： Population dynamics Space debris Kessler syndrome Diffusion Low-Earth orbit

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