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| 1 | Reconstructing the size of individual trees using log data from cut-to-length harvesters in Pinus radiata plantations: a case study in NSW, Australia显示文摘With their widespread utilization, cut-to-length harvesters have become a major source of ‘‘big data'' for forest management as they constantly capture, and provide a daily flow of, information on log production and assortment over large operational areas. Harvester data afford the calculation of the total log length between the stump and the last cut but not the total height of trees. They also contain the length and end diameters of individual logs but not always the diameter at breast height overbark(DBHOB) of harvested stems largely because of time lapse, operating and processing issues and other system deficiencies. Even when DBHOB is extracted from harvester data, errors and/or bias of the machine measurements due to the variation in the stump height of harvested stems from that specified for the harvester head prior to harvesting and diameter measurement errors may need to be corrected. This study developed(1) a system of equations for estimating DBHOB of trees from diameter overbark(DOB) measured by a harvester head at any height up to 3 m above ground level and(2) an equation to predict the total height of harvested stems in P. radiata plantations from harvester data. To generate the data required for this purpose, cut-to-length simulations of more than 3000 trees with detailed taper measurements were carried out in the computer using the cutting patterns extracted from the harvester data and stump height survey data from clearfall operations. The equation predicted total tree height from DBHOB, total log length and the small end diameter of the top log. Prediction accuracy for total tree height was evaluated both globally over the entire data space and locally within partitioned subspaces through benchmarking statistics. These statistics were better than that of the conventional height-diameter equations for P. radiata found in the literature, even when they incorporated stand age and the average height and diameter of dominant trees in the stand as predictors. So this equation when used with harvester data would outperform the conventional equations in tree height prediction. Tree and stand reconstructions of the harvested forest is the necessary first step to provide the essential link of harvester data to conventional inventory, remote sensing imagery and Li DAR data. The equations developed in this study will provide such a linkage for the most effective combined use of harvester data in predicting the attributes of individual trees, stands and forests, and product recovery for the management and planning of P. radiata plantations in New South Wales, Australia. | Kuan Lu Huiquan Bi Duncan Watt Martin Strandgard Yun Li | 2018 | Journal of Forestry Research2018，29，1： | 4 |
| 2 | 反思金融深化:新兴市场的稳定与发展显示文摘有深度和流动性良好的金融系统,加上有丰富的金融工具可抵御金融冲击,还可以增加一国金融的稳定性。但是金融发展或许存在一个边界,越过此边界进一步发展其收益或将下降。本文通过研究新兴市场发现:一、大部分新兴市场金融进一步发展仍然对经济的增长和稳定有利。二、金融发展对经济增长的促进作用是倒U型的,在越过高点之后金融深化对要素生产率的促进作用将下降。三、如果金融发展过快,快速深化的金融产业可能引发经济和金融动荡。四、提升金融稳定与金融发展之间没有太大冲突,更好的金融监管有助于提升金融稳定,促进金融发展。五、发展金融机构或金融市场不存在通用的顺序,尽管前者对经济的作用在下降而后者在上升。 | IMF课题组 Ratna Sahay Martin Cihak Papa N’Diaye Adolfo Barajas Ran Bi Diana Ayala Yuan Gao Annette Kyobe Lam Nguyen Christian Saborowski Katsiaryna Svirydzenka Seyed Reza Yousefi 胡妍斌 王辰 | 2015 | 新金融2015，0，10： | 2 |
| 3 | A new model for predicting the total tree height for stems cut-to-length by harvesters in Pinus radiata plantations显示文摘A new model for predicting the total tree height for harvested stems from cut-to-length(CTL)harvester data was constructed for Pinus radiata(D.Don)following a conceptual analysis of relative stem profi les,comparisons of candidate models forms and extensive selections of predictor variables.Stem profi les of more than 3000 trees in a taper data set were each processed 6 times through simulated log cutting to generate the data required for this purpose.The CTL simulations not only mimicked but also covered the full range of cutting patterns of nearly 0.45×106 stems harvested during both thinning and harvesting operations.The single-equation model was estimated through the multipleequation generalized method of moments estimator to obtain effi cient and consistent parameter estimates in the presence of error correlation and heteroscedasticity that were inherent to the systematic structure of the data.The predictive performances of our new model in its linear and nonlinear form were evaluated through a leave-one-tree-out cross validation process and compared against that of the only such existing model.The evaluations and comparisons were made through benchmarking statistics both globally over the entire data space and locally within specifi c subdivisions of the data space.These statistics indicated that the nonlinear form of our model was the best and its linear form ranked second.The prediction accuracy of our nonlinear model improved when the total log length represented more than 20%of the total tree height.The poorer performance of the existing model was partly attributed to the high degree of multicollinearity among its predictor variables,which led to highly variable and unstable parameter estimates.Our new model will facilitate and widen the utilization of harvester data far beyond the current limited use for monitoring and reporting log productions in P.radiata plantations.It will also facilitate the estimation of bark thickness and help make harvester data a potential source of taper data to reduce the intensity and cost of the conventional destructive taper sampling in the fi eld.Although developed for P.radiata,the mathematical form of our new model will be applicable to other tree species for which CTL harvester data are routinely captured during thinning and harvesting operations. | Chenxi Shan Huiquan Bi Duncan Watt Yun Li Martin Strandgard Mohammad Reza Ghaff ariyan | 2021 | Journal of Forestry Research2021，32，1： | 2 |
| 4 | Revision surgery following operations for lumbar stenosis显示文摘 | Deyo RA Martin BI Kreuter W | 2011 | ] Bone Joint Surg Am2011，93，21： | 1 |
| 5 | Trends,major medical complieations and charges associated with surgery for lumbar spinal stenosis in older adults显示文摘 | Deyo RA Mirza SK Martin BI | 2010 | JAMA2010，303，13： | 1 |
| 6 | Interspinous spacers compared with decompression or fusion for lumbar stenosis:complications and repeat operations in the Medicare population显示文摘 | Deyo RA Martin BI Ching A | 2013 | Spine2013，38，10： | 1 |
| 7 | Using the spine surgical invasiveness index to identify risk of surgical site infection:a multivariate analysis显示文摘 | Cizik AM Lee MJ Martin BI | 2012 | J Bone Joint Surg Am2012，94，4： | 1 |
| 8 | Reoperation rates following lumbar spine surgery and the influence of spinal fusion procedures 显示文摘 | Martin BI Mirza SK Comstock BA | 2007 | Spine2007，32，3： | 1 |
| 9 | Coping with a layoff:A longitudinal study of victims显示文摘 | Bennett N Martin C L Bies R J | 1995 | Journal of Management1995，21，6： | 1 |
| 10 | Trends, major medical complications, and charges associated with surgery for lumbar spinal stenosis in older adults 显示文摘 | Deyo RA Mirza SK Martin BI | 2010 | JAMA2010，303，13： | 1 |
| 11 | Trends,Major Medical Complications,and Charges Associated With Surgery for Lumbar Spinal Stenosis in Older Adults显示文摘 | Deyo RA Mirza SK Martin BI | | 0，，13： | 1 |
| 12 | Reoperation rates following lumbar spine surgery and the influence of spinal fusion procedures显示文摘 | Martin BI Mirza SK Comstock BA | 2007 | Spine2007，32，3： | 1 |
| 13 | Trends, major medical corn-plications, and charges associated with surgery for lumbar spinal stenosis in older aduhs显示文摘 | Deyo RA Mirza SK Martin BI | 2010 | JAMA2010，303，13： | 1 |
| 14 | Expenditures and health status among adults with back and neck problems显示文摘 | Martin BI Deyo RA Mirza SK | 2008 | JAMA2008，299，6： | 1 |
| 15 | Back pain prevalence and visit rates:estimates from US national surveys 2002显示文摘 | Deyo RA Mirza SK Martin BI | | 0，，23： | 1 |
| 16 | Reoperation rates following lumbar spine surgery and the influence of spinal fu- sion procedures 显示文摘 | Martin BI Mirza SK Comstock BA | 2007 | Spine ( Phila Pa 1976)2007，32，： | 1 |
| 17 | IL28B polymorphism is associated with treatment response in patients with genotype 4 chronic hepatitis C显示文摘 | Tarik Asselah Simon De Muynck Philippe Bro?t Julien Masliah-Planchon Maud Blanluet Ivan Bièche Martine Lapalus Michelle Martinot-Peignoux Olivier Lada Emilie Estrabaud Qian Zhang Ahmed El Ray Dominique Vidaud Marie-Pierre Ripault Nathalie Boyer Pierre Bed | 2011 | Journal of Hepatology2011，，3： | 1 |
| 18 | Reoperation rates following lumbar spine surgery and the influence of spinal fusion procedures显示文摘 | Martin BI Mirza SK Comstoek BA | 2007 | Spine2007，32，3： | 1 |
| 19 | Using the spine surgical invasiveness index to identify risk of surgical site infection:a multivariate analysis显示文摘 | Cizik AM Lee MJ Martin BI | 2012 | J Bone Joint Surg Am2012，94，4： | 1 |
| 20 | Interactive Effects of Procedural Jus-tice and Outcome Negativity on Victims and Survivors of Job Loss显示文摘 | BROCKNER J KONOVSKY M COOPER-SCHNEIDER R FOL-GER R MARTIN C BIES R J | 1994 | Academy of Management Journal1994，37，2： | 1 |
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