智慧BIM乔木模型：从设计图纸到施工 现场

现有的BIM应用软件提供的乔木模型多为RPC或高 精度3D模型等3D CAD类型。这些模型着重于表达美感或进 行展示,无法反映根系情况。虽然可能包含一定附加属性,但 表达乔木生长和空间需求的功能有限。因而,冲突检查、工序 调度等BIM的优势功能无从应用。风景园林实践领域已就此问 题开始构建自己的模型库,但能够准确反映现状树木真实尺寸 体量,以及现状树木和规划树木未来空间需求的模型仍未广泛 出现。提出一种基于树冠、树干和根系构型与生长功能的实体/ 网面封装建模方法构建BIM乔木模型。模型形态通过一组参数 调整,并根据树龄和反映环境限制因子的值来反映其变化。所 包含的数据和参数数量随后期设计阶段所需的LoD(详细层级) 及专业实践的具体要求而增加。该模型可以与提供本地区内外 苗木商品信息的植物数据库连接使用。     

International Commodity Taxation under Monopolistic Competition

We analyze non‐cooperative commodity taxation in a two‐country trade model characterized by monopolistic competition and international firm and capital mobility. In this setting, taxes in one country affect foreign welfare through the relocation of mobile firms and through changes in the rents accruing to capital owners. With consumption‐based taxation, these fiscal externalities exactly offset each other and the non‐cooperative tax equilibrium is Pareto efficient. With production‐based taxation, however, there are additional externalities on the foreign tax base and the foreign price level that lead non‐cooperative tax rates to exceed their Pareto efficient levels.     

A Theory of Menu Federalism: Decentralization by Political Agreement

This paper analyzes agreements between governments that determine the division of policy-making power between central and regional governments. Our analysis demonstrates that initial circumstances and political risks affect the degree of centralization that will be adopted, and that asymmetric forms of federalism are often consequences of ongoing negotiations between regional and central governments over the assignment of policy-making authority. We analyze three settings where gains from constitutional exchange may exist: (i) the under-centralized state, (ii) the over-centralized state, and (iii) the constitutional convention. In each case, an asymmetric form of federalism is the predicted outcome, although the degree of asymmetry differs according to starting point. Modern and historical examples are used to illustrate the relevance of our analysis.     

Interbank Relationships and the Credit Channel in Germany

A crucial condition for the existence of a credit channel through bank loansis that monetary policy should be able to change bank loan supply. This papercontributes to the discussion on this issue by presenting empirical evidence fromdynamic panel estimations based on a dataset that comprises individual balancesheet information on all German banks. It shows that the average bank reduces itslending more sharply in reaction to a restrictive monetary policy measure the lowerits ratio of short-term interbank deposits to total assets. A dependence on its size canonly be found if explicitly controlled for this dominating effect. Overall, the evidenceis compatible with the existence of a credit channel but the results indicate that it is weakened by the network structures that exist in the German banking system.     

Gamified interactions: whether,when, and how games facilitate self–brand connections

Firms increasingly use games to interact with their customers. Yet, surprisingly little is known about whether, when, and how such “gamified” interactions engage consumers with a firm’s brand, thereby facilitating self–brand connections. Building on flow theory, we show that gamified interactions that are highly interactive and optimally challenging facilitate self–brand connections, because such games lead to emotional and cognitive brand engagement. A field study and three experiments across various product domains and game designs support our theory. We also identify conditions under which consumers do not become engaged with a brand, namely when firms restrict their decisional control either to voluntarily participate in the game (i.e., compulsory play) or to spend as much time as desired playing the game (i.e., time pressure). Our findings advance existing knowledge about the use of games in marketing and provide important implications for how marketers can harness their potential to build self–brand connections.     

WILL GERMAN BANKS EARN THEIR COST OF CAPITAL?

In recent years, the German banking sector has overcome major challenges such as the global financial crisis and the European debt crisis. This paper analyzes a recent development as a particular determinant of the future outlook for the German banking sector. Interest rates are at historically low levels and may remain at these levels for a considerable period of time. Such levels pose a specific challenge to banks which are heavily dependent on interest income, as is the case for most German banks. We consider different interest rate scenarios and analyze the extent to which they cause a further narrowing of the interest rate margin. Our results indicate that a projected decline in this margin will result in no more than 20% of German banks earning a cost of capital of 8% by the end of this decade. However, we show that this decline is alleviated by the fact that German banks can apply a special feature of German accounting standards by using hidden and open reserves. We discuss how these income smoothing tools will provide a cushion that supports short‐ and medium‐term adjustments through a buffer effect. (JEL G21, G28)     

GOVERNMENT SIZE AND GROWTH: A REJOINDER

In our 2011 survey of the literature in the Journal of Economic Surveys on the effect of government size on economic growth in wealthy countries we find a relatively consistent pattern: An increase in government size by 10 percentage points is associated with a 0.5–1 percentage point lower annual growth rate. This conclusion is questioned by Colombier. In this rejoinder we present a rebuttal of Colombier's argument based on a detailed scrutiny of his own statistical evidence and regression results. Furthermore, we note that several new papers that have appeared since our original paper was published give support to our main conclusion.     

Walking and Talking Corporate Social Responsibility: Implications of Firm Size and Organizational Cost

In this paper we address two interrelated research gaps in the Corporate Social Responsibility (CSR) literature. The first results from a lack of understanding of different patterns of CSR engagement with respect to CSR talk (impression management and the creation of symbolic images and documentation) and CSR walk (substantive implementation of CSR policies, structures and procedures). Related to this, the second gap concerns limited knowledge about the influence of firm size on CSR engagement. We develop a conceptual model that explains differences in CSR talk versus walk based on organizational cost and firm size. This allows us to theorize the antecedents of what we call the large firm implementation gap (large firms tend to focus on communicating CSR symbolically but do less to implement it into their core structures and procedures) and vice versa the small firm communication gap (less active communication and more emphasis on implementation). Our model expands a new theoretical understanding of CSR engagement based on as yet underemphasized firm‐level antecedents of CSR, and opens up several new avenues for future, and in particular comparative, research.     

Macroeconomic Fluctuations and Bank Lending: Evidence for Germany and the Euro Area

Abstract. This paper analyzes the dynamic response of loans to the private sector and of economic activity to aggregate supply, demand and monetary policy shocks in Germany and the euro area based on a standard macroeconomic VAR using sign restrictions to identify the structural shocks. The main results of this analysis are that (i) with the exception of the response to the supply shock in Germany, the response of loans to the three macroeconomic shocks is rather weak and in most cases insignificant; (ii) the 2000–05 credit slowdown and weak economic performance in Germany were primarily driven by adverse supply shocks; and (iii) the marked slowdown in credit creation in Germany over this period actually represents a realignment of the outstanding stock of loans with its deterministic level. In order to assess the role of bank lending in the transmission of macroeconomic shocks, we further perform counterfactual simulations and analyze the dynamic responses of German loan subaggregates in order to test the distributional implications of potential credit market frictions. These exercises do not indicate that credit market frictions play an amplifying role in the transmission of macroeconomic fluctuations.