نتایج جستجو برای: harvest function

تعداد نتایج: 1234939  

2012
Silvija Vlah Jerić

In this work we consider the supply chain management in olive oil industry. We construct the mixed-integer programming model connecting the optimization of olives harvesting and storage and olive oil production. The goal is to maximize the olive oil producer profit consisting of revenue, production cost and storage cost. In the same time, we have to take into the consideration the farmers’ (sup...

Journal: :Mathematical biosciences 2004
Rui Dilão Tiago Domingos Elman M Shahverdiev

We analyse the effect of harvesting in a resource dependent age structured population model, deriving the conditions for the existence of a stable steady state as a function of fertility coefficients, harvesting mortality and carrying capacity of the resources. Under the effect of proportional harvest, we give a sufficient condition for a population to extinguish, and we show that the magnitude...

2006
Stephen J. Mitchell

The Table Interpolation Program for Stand Yields (tipsy) enables forest managers and timber supply analysts to explore the impacts of variable retention. tipsy variable retention adjustment factors (vrafs) are calculated based on the level and pattern of both group and dispersed tree retention using four primary variables from the retained stand: percent crown cover, average group or crown size...

2008
Xing Sun Ian A. Munn Changyou Sun Anwar Hussain

Understanding how quickly landowners regenerate their timberlands after harvest is critical to developing policies to improve forest productivity. Using survey data from 81 counties in Mississippi from 1996 to 2006, this study investigated the length of the time interval between harvest and reforestation. Non-parametric duration analysis was used to examine how long NIPF landowners waited to re...

2015
WEN J. WANG HONG S. HE FRANK R. THOMPSON JACOB S. FRASER BRICE B. HANBERRY WILLIAM D. DIJAK

Most temperate forests in U.S. are recovering from heavy exploitation and are in intermediate successional stages where partial tree harvest is the primary disturbance. Changes in regional forest composition in response to climate change are often predicted for plant functional types using biophysical process models. These models usually simplify the simulation of succession and harvest and may...

2012
Xiaobai Li Wengui Yan Hesham Agrama Limeng Jia Aaron Jackson Karen Moldenhauer Kathleen Yeater Anna McClung Dianxing Wu

Harvest index is a measure of success in partitioning assimilated photosynthate. An improvement of harvest index means an increase in the economic portion of the plant. Our objective was to identify genetic markers associated with harvest index traits using 203 O. sativa accessions. The phenotyping for 14 traits was conducted in both temperate (Arkansas) and subtropical (Texas) climates and the...

2011
Virginie Rolland Jeffrey A. Hostetler Tommy C. Hines Fred A. Johnson H. Franklin Percival Madan K. Oli

Context. Hunting-related (hereafter harvest) mortality is assumed to be compensatory in many exploited species. However,whenharvestmortality is additive, hunting can lead topopulationdeclines, especially onpublic landwherehunting pressure can be intense. Recent studies indicate that excessive hunting may have contributed to the decline of a northern bobwhite (Colinus virginianus) population in ...

Journal: :Ecological applications : a publication of the Ecological Society of America 2009
Elise F Zipkin Clifford E Kraft Evan G Cooch Patrick J Sullivan

Population control through harvest has the potential to reduce the abundance of nuisance and invasive species. However, demographic structure and density-dependent processes can confound removal efforts and lead to undesirable consequences, such as overcompensation (an increase in abundance in response to harvest) and instability (population cycling or chaos). Recent empirical studies have demo...

2017
Nacer Bellaloui James R. Smith Alemu Mengistu

The timing of harvest is a major factor affecting seed quality in soybean, particularly in Midsouthern USA, when rain during harvest period is not uncommon. The objective of this research was to evaluate the effects of time of harvest on soybean seed quality (seed composition, germination, seed coat boron, and lignin) in high germinability (HG) breeding lines (50% exotic) developed under high h...

2009
E A Schaefers David M Clausen

For analyzing the harvest of the Gulf of Mexico shrimp fishery, Griffin et al. (1976) have developed an equation that relates shrimp yield to freshwater discharge of the Mississippi River and fishing effort of Gulf shrimp vessels. The yield equation (referred to as Griffin's equation) is a modified Spillman production function (Heady and Dillon 1972). The Spillman function had its origin in agr...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید