Analysis of the hydrophysical structure of the Sea of Azov in the period of the bottom anoxia development

The hydrophysical and hydrochemical structure of the Sea of Azov, with developed bottom anoxia, was studied during the RV “Akvanavt” cruise from July 31 to August 03, 2001. The anoxic zone with a thickness from 0.5 to 4 m above the bottom was found in all deep regions of the Sea. Concentrations of hydrochemical parameters were similar to the pronounced anoxic conditions (about 90 mmol m^− 3 of hydrogen sulfide, 17 mmol m^− 3 of ammonia, 6 mmol m^− 3 of phosphate, 7 mmol m^− 3 of total manganese). The hydrophysical structure was characterized by the uniform distribution of temperature in the upper 6–7 m mixed layer (UML). Below this a thin (0.4–0.8 m) thermocline layer was observed, just above the anoxic waters. Formation of this phenomenon was connected with that summer weather conditions. Intensive rains led to increased influx of river waters in June. That resulted in large input of allochtonous organic matter (OM) and inorganic nutrients; the latter were consumed on the additional autochthonous organic matter production. In July the weather was characterized by a significant rise in the daily averaged air temperature and large oscillations of temperature during the day. In this period a wind of constant direction was absent, but wind bursts were observed. The completed analyses showed that the formation of such a structure could be connected with the following factors: (i) positive growth trends of the daily averaged temperature and the daily oscillations of temperature, (ii) presence of wind bursts. The joint action of these factors resulted in the formation of the UML. The amplitude of wind bursts determined the depth of UML, and the value of trend determined the value of the temperature change in the thermocline. An initial presence of bottom halocline (caused by the Black Sea water influx to the bottom of the Sea of Azov) prevented the heating of the bottom layer and therefore led to an increase of vertical gradient of temperature in the thermocline. The spatial distribution of the turbulent exchange coefficient confirmed the existence of a “stagnation” area located above the anoxia zone, which is also, apparently, the reason for its occurrence.     

Site Selection Appraisal for Tidal Turbine Development in the River Mersey

This paper used a specialist software package to produce a detailed model of the River Mersey estuary, which can be subjected to a range of simulated tidal conditions. The aim of this research was to use the validated model to identify the optimal location for the positioning of a tidal turbine. Progress was made identifying a new optimal site for power generation using velocity data produced from simulations conducted using the MIKE 3 software. This process resulted in the identification of site 8, which sits mid-river between the Morpeth Dock and the Albert Dock, being identified as the favoured location for tidal power generation in the River Mersey. Further analysis of the site found that a 17.2-m diameter single rota multidirectional turbine with a 428-kW-rated capacity could produce 1.12 GWh annually.     

梅西河潮流能水轮机开发的场地选择评价研究（英文）

This paper used a specialist software package to produce a detailed model of the River Mersey estuary, which can be subjected to a range of simulated tidal conditions. The aim of this research was to use the validated model to identify the optimal location for the positioning of a tidal turbine. Progress was made identifying a new optimal site for power generation using velocity data produced from simulations conducted using the MIKE 3 software. This process resulted in the identification of site 8, which sits mid-river between the Morpeth Dock and the Albert Dock, being identified as the favoured location for tidal power generation in the River Mersey. Further analysis of the site found that a 17.2-m diameter single rota multidirectional turbine with a 428-kW-rated capacity could produce 1.12 GWh annually.     

基于无损检测技术的公路改扩建路面质量控制

依托开阳高速公路改扩建工程,采用三维探地雷达和落锤式弯沉仪检测旧路面内部损坏、弯沉、结构层模量,评价旧路面状况和制定病害处治方案;采用红外成像仪、无核密度仪和三维探地雷达检测加铺层的施工温度、空隙率和厚度均匀性.旧路面病害具有隐蔽性和发展特性,三维探地雷达可识别路面内部已形成的病害特征,落锤弯沉仪可识别内部发展中的损伤特征.无损检测技术有利于公路改扩建旧路面病害处治和沥青加铺层的施工质量控制.     

Modelling passengers,buses and stops in traffic microsimulation: review and extensions

In the last decade, significant research efforts and technology have been dedicated to the development of microsimulation tools for a better representation of traffic systems. As a result, several commercial packages appeared and they are used nowadays in the detailed modelling of different transportation systems and operations for specific project evaluations and local designs, mostly within the urban context. After reviewing the specialized literature, we realized that most of these microsimulation tools are oriented to the movement of cars, leaving the public transportation systems as a complement, just for a realistic representation of the transportation system as a whole, but always oriented to simulate cars. In this paper, the objective is to provide guidelines on how to incorporate the necessary entities and components for a proper simulation of public transport systems in a microsimulation environment. Thus, the different approaches to simulate transit systems at a microlevel are discussed, highlighting the necessity of including stops, passengers and transit vehicles explicitly as entities within the microsimulation environment, for modelling transfer operations, control strategies, etc. Several examples are then provided to quantify the impact of such representations, for different cases and potential simulation platforms. Copyright © 2010 John Wiley & Sons, Ltd.     

Timing rules for major transportation investments

The timing decision for major transportation investments – when to build – typically is made without an objective approach for considering the economic value of implementation at different times. This paper uses a model of benefit-cost analysis and derives rules for timing major transportation investments. Three sets of conditions are considered, depending on whether annual benefits of an investment are uncertain and whether the objective is to maximize net present value or simply to achieve positive net present value. The timing rules under each set of conditions are stated in three forms: benefit-cost ratio, annual benefits, and implementation time. The paper compares these timing rules analytically, discusses potential applications, and illustrates them with a numerical example. Consequences of incorrectly using the timing rules are also examined with the example. This revised version was published online in June 2006 with corrections to the Cover Date.     

The Combined Naval Commercial Port (CNCP) in a Latin American setting

Inadequate ports are a major problem in many less developed countries (LDCS). In an era in which international trade involving developing countries is growing rapidly, decisions must be made to provide the necessary infrastructure and superstructure to facilitate the movement of cargo from ship to shore and vice versa. In LDCS, the phenonmenon of the Combined Naval-Commercial Port (CNCP) has not undergone scrutiny. This paper is concerned with describing the nature of the Latin American CNCP. The hypothesis is that commercial port interests have been adversely affected by coexistence. The results of an unquiry comprise the main body of this research.     

机务段办公自动化系统中的档案管理

为实现机务段档案管理工作办公自动化、管理规范化、现代化,设计了机务段办公自动化系统中的档案管理子系统。介绍了档案管理系统要实现的功能及其数据流程,同时指出在档案管理系统设计过程中应注意的问题,以及该系统设计过程中应用的安全技术。应用结果表明:整个系统技术先进,效率高、开放性好,完全能满足用户的各项需求,使用后能带来可观的社会效益和经济效益。     

Method for obtaining the modal properties of articulated trains equipped with independently rotating wheels

Independently rotating wheels in railway vehicles could represent an alternative to standard technology as a solution to dynamic problems such as hunting instability or steering forces in curves. Among the proposed design solutions, the train with independently rotating wheels and with the most practical applications is that developed by Talgo. The Talgo technology is based on the use of a passive steering technique of the wheelset through a mechanism. The absence of automatic control systems means that a careful selection of the mechanical parameters of the vehicle is required to improve its dynamic characteristics. Aspects such as dynamic stability or the effect of vibration on passenger comfort could be analysed by extracting the modal properties of the train from mathematical models. In this article, a methodology for determining the low-frequency modal properties of articulated trains equipped with independently rotating wheels and passive steering system (Talgo-type) is proposed. The singularity of this application based on the use of non-conventional wheelsets necessarily involves the development of a specific methodology.