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Symmetry analysis of differential equations with Mathematica /

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Mathematica for theoretical physics

2000年

作者： Baumann gerd.

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Basic Structures and Political Implications of a Sustainable Welfare Model

1000年

作者： Baumann gerd.

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Journal of Environmental Science and Engineering(A) 2014年第4期3卷 189-203页

作者： gerd Ahlertt Bemd Meyer Roland Zieschank Hans Diefenbacher GWS (Institute of Economic Structures Research) Osnabriick 49080 Germany FFU (Environmental Policy Research Centre) Berlin 14195 Germany FEST (Institute of Interdisciplinary Research) Heidelberg 69118 Germany

A synopsis of political welfare concepts, which are currently discussed under labels such as ＂green growth＂, ＂zero growth＂ and ＂degrowth＂, has identified fundamental shortcomings concerning the informational bases of the complex links between ecological, social and economic systems, which were taken into account in the creation of the concept. In the development of a concept for political action, a rationally acting environmental policy cannot neglect reflecting on which economic, ecological and social contexts have to be taken into account and on which normative statements its decisions should be grounded. The proposed sustainable welfare model consists of a positive impact and a normative decision model. The positive model provides a description of the ＂world＂ with which the effects of the various options for action on the environmental, social and the economic systems can be assessed. The normative model is a tool for selecting and assessing the options for action in pursuing the desired goal of sustainable welfare development. Principally the key environmental goals are prearranged to socio-economic goals. The model at hand provides the reference points for the development of a sustainable welfare concept, which can be used as a political action plan in the context of environmental policy.

关键词： Planetary boundaries environmental and socio-economic goals sustainable welfare model sustainable development green economy.

Research on Traffic Sign Detection Based on Improved YOLOv8

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Journal of Computer and Communications 2023年第7期11卷 226-232页

作者： Zhongjie Huang Lintao Li gerd Christian Krizek Linhao Sun School of Computer and Information Engineering Xinxiang University Xinxiang China Department of Applied Mathematics and Physics UAS Technikum Wien Vienna Austria

Aiming at solving the problem of missed detection and low accuracy in detecting traffic signs in the wild, an improved method of YOLOv8 is proposed. Firstly, combined with the characteristics of small target objects in the actual scene, this paper further adds blur and noise operation. Then, the asymptotic feature pyramid network (AFPN) is introduced to highlight the influence of key layer features after feature fusion, and simultaneously solve the direct interaction of non-adjacent layers. Experimental results on the TT100K dataset show that compared with the YOLOv8, the detection accuracy and recall are higher. .

关键词： Traffic Sign Detection Small Object Detection YOLOv8 Feature Fusion

光化学条件下(β-重氮-α,α-二氟乙基)膦酸酯与羧酸的酯化反应

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化学学报 2021年第6期79卷 747-750页

作者：刘江徐敬成 Romana Pajkert 梅海波 gerd-Volker Röschenthaler 韩建林江苏省林业资源高效加工利用协调创新中心化学工程学院南京林业大学南京210037 不来梅雅各布大学生命科学与化学学院 28759

利用可见光促进的O-H插入反应可以在温和条件下实现羧酸与原位生成的(β-重氮-α,α-二氟乙基)膦酸酯的酯化反应,以良好的产率得到了含有α,α-二氟甲基膦酸酯的羧酸酯类化合物.该反应操作简单,对于不同的官能团具有良好的适应性.因此,... 详细信息

利用可见光促进的O-H插入反应可以在温和条件下实现羧酸与原位生成的(β-重氮-α,α-二氟乙基)膦酸酯的酯化反应,以良好的产率得到了含有α,α-二氟甲基膦酸酯的羧酸酯类化合物.该反应操作简单,对于不同的官能团具有良好的适应性.因此,这一反应为α,α-二氟甲基膦酸酯衍生物的合成提供了一种高效的策略.

关键词：二氟重氮乙烷 (β-重氮-α,α-二氟乙基)膦酸酯可见光促进 O-H插入掩蔽的卡宾

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德国FDI在中国失败的原因与对策研究

德国FDI在中国失败的原因与对策研究

作者： gerd-Andreas Straβer 华东理工大学

学位级别：硕士

纵然这些失败案例目前很少受到重视甚至被完全忽视,但它们却可能是帮助鉴别并最终克服这些障碍的有力方式。论文第一部分在详细研究现有文献及调查结果的基础上着重分析外商在华直接投资的模式及所面临的困难,以便找出导致外商撤资退出... 详细信息

纵然这些失败案例目前很少受到重视甚至被完全忽视,但它们却可能是帮助鉴别并最终克服这些障碍的有力方式。论文第一部分在详细研究现有文献及调查结果的基础上着重分析外商在华直接投资的模式及所面临的困难,以便找出导致外商撤资退出中国市场的问题所在。本文介绍了外商对华直接投资的历史和结构,以及吸引外商对华直接投资的重要因素。本部分还概述了外商直接投资对中国经济的影响以及外资公司遇到的常见问题。此外,还将印度作为外商直接投资领域的竞争对手,与中国进行了比较。第二部分重点介绍了德国外商对华直接投资的特征,突出中国市场对德国公司的重要性并说明德国外商对华直接投资的规模和范围。第三部分涵盖对德国公司在华投资过程中所遇到的问题进行的研究。并借助两起针对近期退出中国市场的德国公司案例的调查研究分析德企所面临的难题。案例研究是一种合适的形式,原因是只有为数不多的公司愿意参与此类研究,因而无法使用定量数据,而且通过案例研究,可以提供深入的信息。从中得出的结论为：外商在进入中国市场前需做好充足的准备并预先考虑自身商业模式是否合适;以效率为核心的德国在华投资企业未来有必要通过改变自身以获得并保持成功。

关键词：外商直接投资中德外商直接投资决定性因素难题障碍印度

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用GPS进行乡村地籍测量

测绘译丛 1993年第3期 39-45页

作者： gerd.,GP 李全信

Misplaced faith—limitations of the first appearance datum(FAD) in chronostratigraphy and proposal of more robust Lower Cambrian correlation standards

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Misplaced faith—limitations of the first appearance datum(F...

Microvascular invasion of hepatocellular carcinoma predicts microvascular invasion of its recurrence: potential implications for salvage liver transplantation?

The 17th Field Conference of the Cambrian Stage Subdivision Working Group,International Subcommission on Cambrian Stratigraphy and Celebration of the 30th Anniversary of the Discovery of the Kaili Biota

作者： E D LANDING gerd GEYER New York State Museum 222 Madison AvenueAlbanyNew York 12230USA Department of Earth Sciences(Palaeobiology) Uppsala UniversityVillavagen 16752 36 UppsalaSweden Bayerisches Landesamt fur Umwelt Hans - Hogn - Straβe 1295030 HofGermany

The use of the first appearance datum(FAD) of a fossil to define the base of a regional or global chronostratigraphic unit ultimately leads to intractable problems in the resolution allowed by its use as a correlation...

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Hepatobiliary Surgery and Nutrition 2023年第2期12卷 183-191页

作者： Stefan Heinrich Jens Mittler Juliane Theurer Dirk ARidder Jens UMarquardt Arndt Weinmann Uwe Scheuermann gerd Otto Peter RGalle Beate KStraub Hauke Lang General Visceral and Transplantation SurgeryUniversity Hospital of MainzMainzGermany Institute of Pathology University Hospital of MainzMainzGermany Department of Medicine I University Medical Center Schleswig-HolsteinCampus LübeckGermany Department of Medicine I University Hospital of MainzMainzGermany Visceral TransplantationThoracic and Vascular SurgeryUniversity Hospital LeipzigLeipzigGermany

Background:Microvascular invasion(MVI)can only be assessed on a full surgical *** aimed at evaluating,whether the histology of the primary tumor is predictive of MVI in a hepatocellular carcinoma(HCC)***:Patients,who underwent liver resection or orthotopic liver transplantation(OLT)for recurrent HCC from January 2001 until June 2018 were eligible for this retrospective *** specimens were evaluated for HCC subtype/morphology,vessels encapsulating tumor clusters(VETC)-pattern and *** parameters were analyzed using χ^(2)-test andϕ-values,with P values<0.05 being considered ***:Of 230 HCC recurrences,37(16.1%)underwent repeated liver resection(n=22)or OLT(n=15).Of these,67.6%initially exceeded the Milan *** correlated Milan criteria(P=0.005),tumor size(P=0.015)and VETC-pattern(P=0.034)in the primary *** recurrences shared many features of the primary HCC such as tumor grade(P=0.002),VETC-pattern(P=0.035),and MVI(P=0.046).In recurrences,however,only the concordance with the Milan criteria correlated with MVI(P=0.018).No patient without MVI in the primary HCC revealed MVI on early recurrence(<2 years)(P=0.035).Conclusions:HCC recurrences share many biological features of the primary ***,early recurrences of MVI-negative HCC never revealed *** finding offers novel concepts,e.g.,patient selection for salvage OLT.

关键词： Microvascular invasion(MVI) resection selection vessels encapsulating tumor clusters(VETC) angioinvasion salvage transplantation