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• 611. [Article] Heuristic solution techniques for a spatial harvest scheduling problem involving wildlife habitat and timber income

  Three heuristic techniques: simulated annealing (SA), tabu search (TS), and tabu search with strategic oscillation (TSSO), were used to schedule silvicultural activities designed to accelerate development ...

  Citation × Citation Citation Abstract Copy Title: Heuristic solution techniques for a spatial harvest scheduling problem involving wildlife habitat and timber income Author: Sharer, Brian K. Three heuristic techniques: simulated annealing (SA), tabu search (TS), and tabu search with strategic oscillation (TSSO), were used to schedule silvicultural activities designed to accelerate development of older forest structure at both stand and landscape scales over a 2450 acre forest located in northwestern Oregon. Goals for the forest over a 100-year planning horizon included reaching at least 500 acres of older forest structure with at least one contiguous 200-acre (or larger) block as soon as possible. The configuration and location, but not the amounts, of the older forest structure acres and the contiguous block were then free to move about the forest through time while best meeting the goal of producing a high, steady revenue flow over the entire planning horizon subject to restrictions on maximum clearcut patch size. The heuristic techniques were able to provide feasible tactical schedules fulfilling the strategic goals over the entire horizon in ways which traditional forest planning tools cannot. Of the three techniques examined, TSSO produced schedules with the best, most consistent objective function values. SA yielded a wider range of values which were always slightly worse but required only a fraction of the computing time. Straightforward TS produced relatively poor objective function values, most likely because of its inability to search the infeasible regions of the diverse solution space. Estimation of the globally optimal objective function value using Weibull distributions suggested that all TSSO solutions were within 1.8% of the optimum, the best being within .03%, while all SA solutions were within 7.6%, the best being within 1 .7%. However, 95% confidence intervals of the Weibull location parameter estimates for the SA and TSSO distributions did not overlap, despite the fact that both distributions of results failed to be rejected as fitting a Weibull distribution. This disparity again suggests that statistical inference by itself of global optima for heuristic results may be an inadequate means of assessing how "good" a heuristic is. Title: Heuristic solution techniques for a spatial harvest scheduling problem involving wildlife habitat and timber income Author: Sharer, Brian K. Three heuristic techniques: simulated annealing (SA), tabu search (TS), and tabu search with strategic oscillation (TSSO), were used to schedule silvicultural activities designed to accelerate development of older forest structure at both stand and landscape scales over a 2450 acre forest located in northwestern Oregon. Goals for the forest over a 100-year planning horizon included reaching at least 500 acres of older forest structure with at least one contiguous 200-acre (or larger) block as soon as possible. The configuration and location, but not the amounts, of the older forest structure acres and the contiguous block were then free to move about the forest through time while best meeting the goal of producing a high, steady revenue flow over the entire planning horizon subject to restrictions on maximum clearcut patch size. The heuristic techniques were able to provide feasible tactical schedules fulfilling the strategic goals over the entire horizon in ways which traditional forest planning tools cannot. Of the three techniques examined, TSSO produced schedules with the best, most consistent objective function values. SA yielded a wider range of values which were always slightly worse but required only a fraction of the computing time. Straightforward TS produced relatively poor objective function values, most likely because of its inability to search the infeasible regions of the diverse solution space. Estimation of the globally optimal objective function value using Weibull distributions suggested that all TSSO solutions were within 1.8% of the optimum, the best being within .03%, while all SA solutions were within 7.6%, the best being within 1 .7%. However, 95% confidence intervals of the Weibull location parameter estimates for the SA and TSSO distributions did not overlap, despite the fact that both distributions of results failed to be rejected as fitting a Weibull distribution. This disparity again suggests that statistical inference by itself of global optima for heuristic results may be an inadequate means of assessing how "good" a heuristic is. Close

• 612. [Article] Why and When Joint 'Exploitation-Ecosystem Dynamics' Models Should be Used

  Fisheries models are generally built to assess the dynamics of a resource with a given fishing mortality which level can be decided by some “decision maker” and/or which can be an observed process, e.g. ...

  Citation × Citation Citation Abstract Copy Title: Why and When Joint 'Exploitation-Ecosystem Dynamics' Models Should be Used Author: Laloë, Francis Fisheries models are generally built to assess the dynamics of a resource with a given fishing mortality which level can be decided by some “decision maker” and/or which can be an observed process, e.g. times series proportional to some observed values of fishing effort. In these cases, the resource dynamics is represented “conditionally to” fishing mortality. This mortality must be therefore primarily defined in reference to the definition of the resource Such models can be used to make stock assessment from historical data and to find which fishing mortality values could lead to some objective that can be some optimal or acceptable situation. If the values of fishing mortality can be decided by some unique institution, this knowledge of “best or acceptable mortality values” is of great interest for decision support. If not, it becomes insufficient to identify which decision of which institution could lead to obtain some given set of fishing mortalities. This situation may arise if there is a high number of fishing units belonging to various fishing fleets that may decide to generate fishing mortalities distributions among several available possibilities, according to their own interest. Examples of such problems will be presented from a Senegalese case study where several fishing fleets harvest on a common multispecies resource. Some other examples will be given from case studies identified in the context of the program ECOST with the development of a generic model which represents the joint dynamics of fishing activity and resource. Title: Why and When Joint 'Exploitation-Ecosystem Dynamics' Models Should be Used Author: Laloë, Francis Fisheries models are generally built to assess the dynamics of a resource with a given fishing mortality which level can be decided by some “decision maker” and/or which can be an observed process, e.g. times series proportional to some observed values of fishing effort. In these cases, the resource dynamics is represented “conditionally to” fishing mortality. This mortality must be therefore primarily defined in reference to the definition of the resource Such models can be used to make stock assessment from historical data and to find which fishing mortality values could lead to some objective that can be some optimal or acceptable situation. If the values of fishing mortality can be decided by some unique institution, this knowledge of “best or acceptable mortality values” is of great interest for decision support. If not, it becomes insufficient to identify which decision of which institution could lead to obtain some given set of fishing mortalities. This situation may arise if there is a high number of fishing units belonging to various fishing fleets that may decide to generate fishing mortalities distributions among several available possibilities, according to their own interest. Examples of such problems will be presented from a Senegalese case study where several fishing fleets harvest on a common multispecies resource. Some other examples will be given from case studies identified in the context of the program ECOST with the development of a generic model which represents the joint dynamics of fishing activity and resource. Close

• 613. [Article] Production Efficiency of the Tuna fleet of Azores and Madeira: a technical and strategic analysis

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Production Efficiency of the Tuna fleet of Azores and Madeira: a technical and strategic analysis Author: Dias, Joao, Mendonca, Marta Abstract only. Title: Production Efficiency of the Tuna fleet of Azores and Madeira: a technical and strategic analysis Author: Dias, Joao, Mendonca, Marta Abstract only. Close

• 614. [Article] Capture-based aquaculture - sustainable value adding to capture fisheries?

  Capture-based aquaculture (CBA) is an industry that utilizes wild-captured specimens as stocking animals for ongrowing or storage. This yields an intriguing direct link between capture fisheries and aquaculture ...

  Citation × Citation Citation Abstract Copy Title: Capture-based aquaculture - sustainable value adding to capture fisheries? Author: Dreyer, Bent, Hermansen, Oystein Capture-based aquaculture (CBA) is an industry that utilizes wild-captured specimens as stocking animals for ongrowing or storage. This yields an intriguing direct link between capture fisheries and aquaculture of these resources. Examples of CBA are collection of early life stages of many crustaceans and adolescent tunas for grow-out in aquaculture systems. Cod CBA competes with capture fisheries and closed-cycle aquaculture. This paper discusses value adding properties of these in order to evaluate the relative costs and value positions according to the Hunt and Morgan (1995) competitiveness matrix. CBA on cod is found to be in a superior value position and at a cost disadvantage. Advantages primarily stem from a quantitatively high yield, ability to supply during the lean season and large fish for sale. Higher capture, farming and slaughter costs are negative factors. Capture of juveniles for CBA imposes an externality on the capture fishery. When evaluating potential or ongoing CBA operations, this has to be taken into account. For cod CBA, this is internalized as cod for stocking has to be caught within regular quotas. Attention from economics and resource management research is scarce, as we find only one study that calculates the economic benefits from alternative uses of juveniles. FAO have proposed strict criteria for CBA evaluation. Our findings indicate that CBA can be economically preferable, even if not satisfying these criteria. Title: Capture-based aquaculture - sustainable value adding to capture fisheries? Author: Dreyer, Bent, Hermansen, Oystein Capture-based aquaculture (CBA) is an industry that utilizes wild-captured specimens as stocking animals for ongrowing or storage. This yields an intriguing direct link between capture fisheries and aquaculture of these resources. Examples of CBA are collection of early life stages of many crustaceans and adolescent tunas for grow-out in aquaculture systems. Cod CBA competes with capture fisheries and closed-cycle aquaculture. This paper discusses value adding properties of these in order to evaluate the relative costs and value positions according to the Hunt and Morgan (1995) competitiveness matrix. CBA on cod is found to be in a superior value position and at a cost disadvantage. Advantages primarily stem from a quantitatively high yield, ability to supply during the lean season and large fish for sale. Higher capture, farming and slaughter costs are negative factors. Capture of juveniles for CBA imposes an externality on the capture fishery. When evaluating potential or ongoing CBA operations, this has to be taken into account. For cod CBA, this is internalized as cod for stocking has to be caught within regular quotas. Attention from economics and resource management research is scarce, as we find only one study that calculates the economic benefits from alternative uses of juveniles. FAO have proposed strict criteria for CBA evaluation. Our findings indicate that CBA can be economically preferable, even if not satisfying these criteria. Close

• 615. [Article] Strategies for Market Inclusion of Small Scale Fish Farmers of the Tocantins State / Brazil

  presentation

  Citation × Citation Citation Abstract Copy Title: Strategies for Market Inclusion of Small Scale Fish Farmers of the Tocantins State / Brazil Author: Barroso, Renata, Prysthon, Adriano, Pedroza, Manoel, M. V. Flores, Roberto presentation Title: Strategies for Market Inclusion of Small Scale Fish Farmers of the Tocantins State / Brazil Author: Barroso, Renata, Prysthon, Adriano, Pedroza, Manoel, M. V. Flores, Roberto presentation Close

• 616. [Article] Silvicultural and financial analysis of three case studies in the Oregon Coast Range

  Three data sets were examined to determine the costs with and without constrained forest management practices. Two adjacent sites in the Coast Range of Oregon were studied. One of the units was broadcast ...

  Citation × Citation Citation Abstract Copy Title: Silvicultural and financial analysis of three case studies in the Oregon Coast Range Author: Rudd, Christopher Channing Three data sets were examined to determine the costs with and without constrained forest management practices. Two adjacent sites in the Coast Range of Oregon were studied. One of the units was broadcast burned while the adjacent site was left unburned. The stands were projected for growth and yield in the Douglas-Fir Simulator (DFSIM) and Oregon Growth and Yield Projection System (ORGANON). For the simulations a 70 year rotation at 4% interest was used. The total timber volume differed by (1-4%) with the higher volume on the burned unit. Soil expectation value was 4% ($400) higher on the burned unit. Black Rock plot 31, a stand of conifers, was analyzed for retention of various amounts of overstory Douglas-fir trees with an understory of hemlock. Eight different rotations of varying amounts of retained green trees and rotation lengths were forecast with ORGANON. The lowest opportunity cost was realized on the shorter rotation when two trees were left in the overstory and understory hemlocks were pre-commercially thinned. Forest weeding in the first two years of plantations was analyzed at four sites of increasing site index. DFSIM and the stand projection system (SPS) were used to project two different thinning regimes on weeded and non-weeded sites. Weeded sites produced consistently higher timber yields. Thinning to 100 trees per acre (TPA) produced higher yields on the weeded sites and thinning to 150 TPA produced higher yields on non-weeded sites. All weeded sites produced higher value stands ranging between (5-75%). The most pronounced weeding value difference was at the low productivity site and the least value difference was at the high productivity site. Title: Silvicultural and financial analysis of three case studies in the Oregon Coast Range Author: Rudd, Christopher Channing Three data sets were examined to determine the costs with and without constrained forest management practices. Two adjacent sites in the Coast Range of Oregon were studied. One of the units was broadcast burned while the adjacent site was left unburned. The stands were projected for growth and yield in the Douglas-Fir Simulator (DFSIM) and Oregon Growth and Yield Projection System (ORGANON). For the simulations a 70 year rotation at 4% interest was used. The total timber volume differed by (1-4%) with the higher volume on the burned unit. Soil expectation value was 4% ($400) higher on the burned unit. Black Rock plot 31, a stand of conifers, was analyzed for retention of various amounts of overstory Douglas-fir trees with an understory of hemlock. Eight different rotations of varying amounts of retained green trees and rotation lengths were forecast with ORGANON. The lowest opportunity cost was realized on the shorter rotation when two trees were left in the overstory and understory hemlocks were pre-commercially thinned. Forest weeding in the first two years of plantations was analyzed at four sites of increasing site index. DFSIM and the stand projection system (SPS) were used to project two different thinning regimes on weeded and non-weeded sites. Weeded sites produced consistently higher timber yields. Thinning to 100 trees per acre (TPA) produced higher yields on the weeded sites and thinning to 150 TPA produced higher yields on non-weeded sites. All weeded sites produced higher value stands ranging between (5-75%). The most pronounced weeding value difference was at the low productivity site and the least value difference was at the high productivity site. Close

• 617. [Article] Analysis of a multispecies fishery : the commercial fishery fleet of Iquitos, Amazon Basin, Peru

  In this study an analysis of the commercial fishery of the Loreto Region, with emphasis on the fishery fleet of Iquitos, Amazon Basin, Peru, is presented. There is evidence of a progressive replacement ...

  Citation × Citation Citation Abstract Copy Title: Analysis of a multispecies fishery : the commercial fishery fleet of Iquitos, Amazon Basin, Peru Author: Tello, Salvador In this study an analysis of the commercial fishery of the Loreto Region, with emphasis on the fishery fleet of Iquitos, Amazon Basin, Peru, is presented. There is evidence of a progressive replacement of large species by smaller, more productive and lower value species in the landing of the commercial fishery in the Loreto region. Strong fishing pressure has produced a decrease of large valuable species such as Brachyplaiystoma flavicans in the commercial landings of the last ten years. No studies have evaluated the association between catch of the fishery fleet and amplitude and duration of the flooding and fishing effort in the Ucayali and Amazon rivers. Hydrological indices were based on the Amazon water stage taken at Iquitos gauge station in the last ten years. Hydrological indices and fishing effort were used as explanatory variables in a multiple linear regression to answer the question whether the factor responsible for the fluctuation in catch per guilds was the intensity of flooding or the severity of the draw-down period while accounting for fishing effort. This analysis was performed with index of the same year and index of the preceding year. The most significant variables were flood index of the same year and number of fishermen-trips. A positive influence of flooding on the omnivore group was evident in the Ucayali (p-value = 0.03) and Amazon (p-value = 0.001) rivers. However, this influence was negative (p-value = 0.03) on the detritivore group in the Ucayali River at high water which is interpreted as being due to reduced feeding places and stranding process. Number of fishermen-trips explains 90% and 96% of the variance of annual catches in the Ucayali and Amazon rivers, respectively. Additionally, six catch prediction models are presented. Title: Analysis of a multispecies fishery : the commercial fishery fleet of Iquitos, Amazon Basin, Peru Author: Tello, Salvador In this study an analysis of the commercial fishery of the Loreto Region, with emphasis on the fishery fleet of Iquitos, Amazon Basin, Peru, is presented. There is evidence of a progressive replacement of large species by smaller, more productive and lower value species in the landing of the commercial fishery in the Loreto region. Strong fishing pressure has produced a decrease of large valuable species such as Brachyplaiystoma flavicans in the commercial landings of the last ten years. No studies have evaluated the association between catch of the fishery fleet and amplitude and duration of the flooding and fishing effort in the Ucayali and Amazon rivers. Hydrological indices were based on the Amazon water stage taken at Iquitos gauge station in the last ten years. Hydrological indices and fishing effort were used as explanatory variables in a multiple linear regression to answer the question whether the factor responsible for the fluctuation in catch per guilds was the intensity of flooding or the severity of the draw-down period while accounting for fishing effort. This analysis was performed with index of the same year and index of the preceding year. The most significant variables were flood index of the same year and number of fishermen-trips. A positive influence of flooding on the omnivore group was evident in the Ucayali (p-value = 0.03) and Amazon (p-value = 0.001) rivers. However, this influence was negative (p-value = 0.03) on the detritivore group in the Ucayali River at high water which is interpreted as being due to reduced feeding places and stranding process. Number of fishermen-trips explains 90% and 96% of the variance of annual catches in the Ucayali and Amazon rivers, respectively. Additionally, six catch prediction models are presented. Close

• 618. [Article] Determining the validity and reliability of the Nicholas Manual Muscle Tester as a measure of isometric strength in women with arthritis

  The purpose of this investigation was to determine the validity and reliability of the Nicholas Manual Muscle Tester (NMMT), a portable dynamometer, as a measure of the isometric strength in women with ...

  Citation × Citation Citation Abstract Copy Title: Determining the validity and reliability of the Nicholas Manual Muscle Tester as a measure of isometric strength in women with arthritis Author: Sierra, Nelson The purpose of this investigation was to determine the validity and reliability of the Nicholas Manual Muscle Tester (NMMT), a portable dynamometer, as a measure of the isometric strength in women with arthritis. Female subjects (N=13; 66 ± 13.89 yrs.) with arthritis were tested for isometric muscle strength on the shoulder and hip (abduction, adduction, flexion, extension). Subjects were tested on three separate days using NMMT and Kincom 500-H dynamometers. Each subject performed three maximal isometric contractions for each joint action. A visual analog pain scale was used to determine level of pain prior to testing. Reliability values based on intraclass correlations coefficients (R) ranged from .85 to .93., with the exception of shoulder abduction being .49. Validity was determined correlating the mean value of the NMMT score with corresponding Kincom isometric measure. Pearson product moment correlations ranged from (r) .02 to .86, with 4 of 8 values meeting .05 level of significance. Correlation coefficients for pain and isometric force values were inconclusive and ranged from -.305 to .218. Major conclusions were: a) NMMT had high test-retest reliability in this sample; b) NMMT provides little criterion evidence of validity with the Kincom for most movements of hip and shoulder; c) level of pain was not a significant factor in subject reliability. Title: Determining the validity and reliability of the Nicholas Manual Muscle Tester as a measure of isometric strength in women with arthritis Author: Sierra, Nelson The purpose of this investigation was to determine the validity and reliability of the Nicholas Manual Muscle Tester (NMMT), a portable dynamometer, as a measure of the isometric strength in women with arthritis. Female subjects (N=13; 66 ± 13.89 yrs.) with arthritis were tested for isometric muscle strength on the shoulder and hip (abduction, adduction, flexion, extension). Subjects were tested on three separate days using NMMT and Kincom 500-H dynamometers. Each subject performed three maximal isometric contractions for each joint action. A visual analog pain scale was used to determine level of pain prior to testing. Reliability values based on intraclass correlations coefficients (R) ranged from .85 to .93., with the exception of shoulder abduction being .49. Validity was determined correlating the mean value of the NMMT score with corresponding Kincom isometric measure. Pearson product moment correlations ranged from (r) .02 to .86, with 4 of 8 values meeting .05 level of significance. Correlation coefficients for pain and isometric force values were inconclusive and ranged from -.305 to .218. Major conclusions were: a) NMMT had high test-retest reliability in this sample; b) NMMT provides little criterion evidence of validity with the Kincom for most movements of hip and shoulder; c) level of pain was not a significant factor in subject reliability. Close

• 619. [Article] Lies, Damned Lies, and Journalism: Why Journalists Are Failing to Vindicate First Amendment Values and How a New Definition of “The Press” Can Help

  74 pages

  Citation × Citation Citation Abstract Copy Title: Lies, Damned Lies, and Journalism: Why Journalists Are Failing to Vindicate First Amendment Values and How a New Definition of “The Press” Can Help Author: Edelson, Chris Year: 2013, 2012 74 pages Title: Lies, Damned Lies, and Journalism: Why Journalists Are Failing to Vindicate First Amendment Values and How a New Definition of “The Press” Can Help Author: Edelson, Chris Year: 2013, 2012 74 pages Close

• 620. [Article] δ¹³C record of Upper North Atlantic Deep Water during the past 2.6 million years

  Copyright 1995 by the American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: δ¹³C record of Upper North Atlantic Deep Water during the past 2.6 million years Author: Wright, J. D., Oppo, D. W., Prell, W. L., Raymo, M. E., Mix, Alan C., Lohmann, G. P. Copyright 1995 by the American Geophysical Union Title: δ¹³C record of Upper North Atlantic Deep Water during the past 2.6 million years Author: Wright, J. D., Oppo, D. W., Prell, W. L., Raymo, M. E., Mix, Alan C., Lohmann, G. P. Copyright 1995 by the American Geophysical Union Close