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停车收费合理定价——基于需求的旧金山停车定价模式评价

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城市交通 2014年第6期12卷 82-94页

作者： Gregory Pierce donald shoup 石飞王宇袁泉美国加州大学城市规划系洛杉矶ca900951360 南京大学建筑与城市规划学院江苏南京210008 美国南加州大学公共政策学院洛杉矶90089

除少数能够找到便宜停车位的幸运驾驶人外，价格过低和过度拥挤的路内停车位给每个人都制造了难题；其他所有为寻找可用停车位而巡游的驾驶人因此浪费了时间和燃料，导致交通拥堵并且污染空气。价格过高和占用率过低的路内停车位同样存... 详细信息

除少数能够找到便宜停车位的幸运驾驶人外，价格过低和过度拥挤的路内停车位给每个人都制造了难题；其他所有为寻找可用停车位而巡游的驾驶人因此浪费了时间和燃料，导致交通拥堵并且污染空气。价格过高和占用率过低的路内停车位同样存在问题，当路内停车位闲置时，商家失去潜在的顾客，员工失去工作，而城市失去税收。为了解决这些问题，旧金山启动了SFpark项目，通过价格调整实现每个街区有1~2个可用停车位的目标。为了衡量价格如何影响路内停车位占用率，根据项目第一年内超过5000次价格和占用率变动数据计算价格需求弹性。价格需求弹性的平均值为-0.4，但是随时间、地点及其他因素大幅变化。在第一年内平均停车价格下降1%，因此，SFpark调整了停车价格但总体上并未涨价。首次使用测量出的占用率估计路内停车的需求弹性，同时也首次评价随时间和地点而变化的定价模式以用于路内停车管理。指出旧金山可以通过增加驾驶人对变动停车价格的意识，减少残疾标志的滥用以及引入季节性价格调整来改进该项目。其他城市可吸纳绩效停车定价作为拥挤收费的一种形式。

关键词：绩效停车价格需求弹性最优定价

Technology development for ultraintense all-OPcPA systems

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High Power Laser Science and Engineering 2019年第1期7卷 27-37页

作者： J.Bromage S.-W.Bahk I.A.Begishev c.Dorrer M.J.Guardalben B.N.Hoffman J.B.Oliver R.G.Roides E.M.Schiesser M.J.shoup III M.Spilatro B.Webb D.Weiner J.D.Zuegel Laboratory for Laser Energetics University of Rochester

Optical parametric chirped-pulse amplification(OPcPA) [Dubietis et al., Opt. commun. 88, 437(1992)] implemented by multikilojoule Nd:glass pump lasers is a promising approach to produce ultraintense pulses(>1023 W/cm2).Technologies are being developed to upgrade the OMEGA EP Laser System with the goal to pump an optical parametric amplifier line(EP OPAL) with two of the OMEGA EP beamlines. The resulting ultraintense pulses(1.5 kJ, 20 fs,1024 W/cm2) would be used jointly with picosecond and nanosecond pulses produced by the other two beamlines. A midscale OPAL pumped by the Multi-Terawatt(MTW) laser is being constructed to produce 7.5-J, 15-fs pulses and demonstrate scalable technologies suitable for the upgrade. MTW OPAL will share a target area with the MTW laser(50 J, 1 to 100 ps), enabling several joint-shot configurations. We report on the status of the MTW OPAL system, and the technology development required for this class of all-OPcPA laser system for ultraintense pulses.

关键词： nonlinear optics optical parametric chirped-pulse amplification ultrafast lasers ultraintense lasers

MTW-OPAL:a technology development platform for ultra-intense optical parametric chirped-pulse amplification systems

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High Power Laser Science and Engineering 2021年第4期9卷 200-211页

作者： J.Bromage S.-W.Bahk M.Bedzyk I.A.Begishev S.Bucht c.Dorrer c.Feng c.Jeon c.Mileham R.G.Roides K.Shaughnessy M.J.shoupⅢ M.Spilatro B.Webb D.Weiner J.D.Zuegel Laboratory for Laser Energetics University of RochesterNY 14623USA

Optical parametric chirped-pulse amplification implemented using multikilojoule Nd:glass pump lasers is a promising approach for producing ultra-intense pulses(>10^(23)W/cm^(2)).We report on the MTW-OPAL Laser System,an optical parametric amplifier line(OPAL)pumped by the Nd:doped portion of the multi-terawatt(MTW)*** midscale prototype was designed to produce 0.5-PW pulses with technologies scalable to tens of *** choices made for MTW-OPAL were guided by the longer-term goal of two full-scale OPALs pumped by the OMEGA EP to produce 2×25-PW beams that would be co-located with kilojoule-nanosecond ultraviolet *** MTWOPAL campaigns that have been completed since“first light”in March 2020 show that the laser design is fundamentally sound,and optimization continues as we prepare for“first-focus”campaigns later this year.

关键词： nonlinear optics optical parametric chirped-pulse amplification ultra-intense lasers ultrafast lasers

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结直肠癌骨盆复发:切除可能性的决定因素

世界核心医学期刊文摘（胃肠病学分册） 2005年第4期1卷 16-17页

作者： Moore H.G. shoup M. Riedel E. J.G.Guillem 李康 1275 York Avenue New York NY 10021 United StatesDr.

PURPOSE: This study was designed to identify preoperative and intraoperative features of locally recurrent colorectal cancer that predict R0 resection in patients scheduled for attempted complete resection followed by intraoperative radiation therapy. METHODS: Review of a prospective data base identified 119 patients brought to the intraoperative radiation therapy suite for planned complete resection of locally recurrent rectal (n=101) and colon (n=18) cancer between January 1994 and November 2000. R0 resection was achieved in 61 patients. This group was compared with patients in which an R1 (n=38), R2 (n=7), or palliative procedure (n=13) was performed. Variables evaluated included: tumor location, features of the primary tumor, and preoperative findings on computed tomography , magnetic resonance imaging, and history/physical. Tumor location was establish ed by review of operative/pathologic reports and classified as axial (anastomoti c/perineal), anterior (bladder/genitourinary organs), posterior (presacral), or lateral (pelvic sidewall). RESULTS: When recurrence was confined to the axial location only, or axial and anterior locations, R0 resection was achieved signific antly more often than when other locations were involved (P ctively). When a lateral component was present, R0 resection was achieved s ignificantly less often than when there was no lateral component (P = 0.002). For patients with available preoperative computed tomography and/or magnetic reson ance imaging results (n = 70), the finding of lateral tumor involvement was asso ciated with R0 resection significantly less often than when lateral disease was not identified (P = 0.004). cONcLUSIONS: Pelvic recurrences confined to the axial location, or axial and anterior locations, are more likely to be completely re sectable (R0) than those involving the pelvic sidewall. Efforts to enhance preop erative identification and imaging of these patients are clearly justified.

关键词：结直肠癌术中放疗结肠癌姑息手术肿瘤位置原发肿瘤后位患者术前诊断吻合口体格检查