Visual landscape classification in the coastal strip of Santander (Spain)

Abstract

The coastal landscape in Santander, Spain, is analyzed in terms of landscape quality and fragility (or vulnerability). Quality is intended to indicate those areas of major landscape value for conservation purposes. Fragility is utilized to detect areas which could easily deteriorate if certain human activities are carried out. The authors’ study has three clearly differentiated phases. In the first, landscape units are defined and mapped. In the second, units are classified by computerized techniques and grouped according to significance. In the third phase, the true significance of the groups is interpreted. A mountainous, coastal zone in northern Spain was chosen for this study. Landscape units were determined by visual criteria with strong topographical bias. The area covered by each unit is that visible to an observer situated approximately in its center. Each unit is represented by certain biophysical and visual variables. Data were subjected to clustering analysis on the basis of using three ad casum defined “distances.”; The first distance gives unit classifications grouped according to similarity or proximity of their characteristic variables. In this case, inventory data only are used, no subjective value judgments were introduced in the process. Value judgments are made at the end on the resulting groupings of units. Two other distance classifications are determined by the similarity or proximity of the units making up each group according to the landscape quality and fragility values of each unit. In these latter cases, classification is influenced by value judgments introduced at the beginning of the process. These procedures are more subjective but give more congruent results. With each mathematical distance configuration, an analysis is made of the variables shown to be most representative and which have, therefore, shown greatest discriminatory power in selecting final groups. Finally, the different possibilities of the above techniques are discussed as well as their potential generalization to other fields demanding the treatment of qualitative landscape variables.     

Second international conference on new survey methods in transport Hungerford Hill,Australia 12–16 September 1983

The Second International Conference on New Survey Methods in Transport was held at Hungerford Hill, Australia in September 1983. The aims of the conference were to provide a focus for discussion of survey methodology and to establish bench‐marks with respect to the state of the art in various facets of transport surveys. The conference evolved around workshops in twelve key areas: sample design, survey needs for modelling, questionnaire design and piloting, perceptual studies, diary surveys, longitudinal studies, interactive survey methods, freight surveys, traffic surveys, total design concepts, response errors and data correction, and coding and computing.

A number of plenary keynote papers were also presented describing the state of the art in cross‐sectional, longitudinal and interactive survey methods. Emerging from the conference discussions, six key issues were prominent; the gap between the state of the art, as espoused by researchers, and the state of practice, as employed by practioners; the differences in results obtained when employing different survey methods to collect essentially the same data; the emerging use of the telephone for the conduct of interview travel surveys; the interaction between survey methods and demand modelling and the disparate levels of sophistication in the two areas; the role of microcomputers in the design, conduct and analysis of transport surveys; and the need for practitioners to engage in controlled experimentation, so that methodological advances may continue to be made in the field of transport surveys.     

Nigerian railways: problems and prospects

The very special topography of Greece with the hundreds of mainland and island ports generates vast possibilities for developing routing networks to link the ports to each other while satisfying total demand. An algorithm which minimizes total operating costs (fixed and variable) has been adapted and used to determine an optimal network solution. The total operating costs of this solution is compared to the total operating costs of the existing (1964 data) network and the optimal networks when fixed and variable costs are minimized independently. It is found that the actual network follows the minimal total operating costs solution quite closely.     

Sea space capacity and operation strategy analysis system

Sea space planning and congestion management is receiving more attention. However, little work on sea space capacity and strategy analyses can be found in the literature. Compared to other transportation systems, a sea space system has some special features that require consideration. The system capacity also depends on the pattern of traffic using the system. In this paper, we model a sea space as a directional network and capacity models for berthing areas, anchorage areas, fairways and their intersections, as well as the entire sea space system are developed. These models can be used to compute capacity for any given traffic pattern which can be extracted from vessel trip records or from traffic forecasts. To implement these models, a software system called Sea Space Capacity and Strategy Analysis System (SCSAS) has been developed in Visual C + + and is now being used in Singapore.     

Structure,conduct and performance on the major liner shipping routes 1

Market concentration on the major container shipping routes has the potential to reduce contestability, impede effective competition and, as a consequence, inhibit the positive relationship between trade and economic growth. This development could also hamper the ability of economic regions to realize their respective competitive and comparative advantages. Within this context, the structure-conduct-performance (SCP) framework is used to analyse liner shipping dynamics in the transpacific, Europe–Far East and transatlantic trade routes. The analysis finds no conclusive evidence that either the increased concentration of slot capacity or the attempts by shipping lines to boost potential slot capacity (mainly through collaborative arrangements) lead to improved financial performance. The paper concludes that, despite high and increasing concentration among carriers on each of the trade routes analysed, these markets remain contestable.     

软弱地层浅埋大跨隧道跳仓法拆撑空间效应研究北大核心CSCD

对于在软弱、破碎、富水地层中采用双侧壁导坑法修筑的暗挖大跨隧道,跳仓法施工依赖于初期支护的“棚护效应”维持拆撑后大跨结构的稳定性,常常面临拆撑步距小、风险高、效率低、代价大的困境,一旦拆撑方案采取不当,极易造成塌方安全事故。针对这一问题,以青岛地铁4号线错埠岭站为依托工程,通过理论分析与数值计算相结合的手段,论证了拆撑后初期支护“空间棚护效应”主要由“横向成拱效应”和“纵向成梁效应”组成,二者共同维持大跨结构的安全性与稳定性;同时确定了合理、安全、高效、快速的拆撑分区长度与隔仓分区长度,分别为L=9 m、S=18 m,并顺利通过了现场施工的检验。结果表明:软弱地层大跨隧道采用“隔二拆一、先内部后洞口”的拆撑方案是切实可行的,可为后续工程提供借鉴与指导。     

Research developments in numerical methods of fluid-structure interactions in naval architecture and ocean engineering北大核心CSCD

流固耦合问题较为复杂,通常难以通过理论推导求得,而数值模拟则能提供一种有效的解决方案,并被广泛用于船舶与海洋工程领域。流固耦合数值方法根据其网格离散方式,可以分为贴体网格方法、非贴体网格方法、重叠网格方法和粒子类方法 4类,对这4类方法的特点及研究进展进行概述并总结得出:贴体网格方法和重叠网格方法均能精确捕捉界面的变形和演化,适合高雷诺数流动问题,在考虑结构变形时一般采用贴体网格方法,而考虑复杂几何形状的刚体运动时则常采用重叠网格方法;非贴体网格方法能够避免网格的更新操作,使计算较为简单,目前多用于模拟流动控制、水下柔性仿生航行器的研发以及多体运动干扰等问题;粒子类方法因其固有的拉格朗日属性,在模拟涉及自由液面剧烈变形、砰击、爆炸等强非线性流固耦合问题中发挥着重要作用。不同的流固耦合问题属性决定了不同方法的适用性,如何选取适合的数值方法,同时结合各类方法的优势开发新的计算方法以应对更为复杂的问题,是流固耦合算法开发的重要发展方向。     

An interpretation of inter-container port relationships from the demand perspective

Container ports serve as important conduits to facilitate the efficient flow of containerized cargo. As part of value-driven chain systems that intersect between hinterlands, efficiency gains that are generated within the container port will have a direct impact on the competitive advantage of its users and affect the economic potential of both the origin and destination hinterlands. As such, the paper proposes the usage of indifference analysis propounded in microeconomic theory as a useful means to examine inter-container port competition and complementarity. The framework presented can also be combined with Porter's ‘Diamond’ model in order for inter-container port demand relationships to be quantified, measured and analysed in an holistic manner. Apart from analysing inter-port relationships from the standpoint of container ports, the framework can also be used to analyse inter-port relationships from the perspective of other key players in the value-driven chain system and modified accordingly to incorporate various indicators that are deemed to be relevant to these parties.     

土地开发利用和社会经济发展对家庭汽车拥有量的影响——沙特阿拉伯利雅得市和澳大利亚墨尔本市的比较(英文)

汽车保有量取决于城市的土地开发模式。在一定时期内,一个地区的就业、住房、休闲、教育和购物条件以及家庭成员的年龄、性别、收入和家庭规模都会影响到人们对出行目的地和出行方式的选择,而家庭住房位置的影响则是长期的。应用沙特阿拉伯利雅得和澳大利亚墨尔本两座城市数据,分析了城市总体用地水平和人均水平、家庭人口及其距离工作地点的路程等对家庭汽车拥有量的影响,建立了家庭汽车拥有量多项式逻辑模型。模型表明,城市扩张是影响家庭汽车拥有量的主要因素,利雅得市家庭汽车拥有量在2辆以上,而墨尔本市不少于1辆。     

The effect of sloshing on the sway motions of 2D rectangular cylinders in regular waves

In this paper, we investigated the effect of sloshing on the sway motions of two-dimensional rectangular cylinders in regular waves, bearing in mind possible applications for LNG-FPSO and LNG-FSRU. First, we carried out experiments for two models with different drafts, or the same draft but different filling ratios, in which the models were firmly connected to each other. The sway motion was measured with a noncontact video camera. This is an extension of Rognebakke and Faltinsen’s work for a single model (J Ship Res 47(3):208–221, 2003). It was found that the sway motion became small when the incident wave frequency was close to the lowest natural frequency of each model. The sway motion greatly increased when the wave frequency was higher than this frequency. The measured data were compared with numerical results obtained by a single-dominant multi-modal method; relatively good agreement was noted. However, the numerical results deviated from the experimental results near the lowest natural frequency of the smaller model, which was believed to be due to overturning waves, as observed during the experiment. Since this is out of the valid range for the single-dominant multi-modal method, other, more appropriate, methods such as the multi-dominant modal method must be applied instead.