An integrated water/sediment approach to study plankton (a case study in the southern Adriatic Sea)

In marine coastal areas many planktonic species produce resting stages (cysts) that sink to the bottom. Integrated sampling from both the water column (to collect active stages), and sediments (to collect cysts), could be useful to achieve more complete information about plankton composition.In the framework of the “INTERREG II Albania-Italy Project” an oceanographic survey was carried out aboard the r/v “Italica” from 20 to 31 October 2000. The survey interested the northern Albanian coast (Gulf of Drin) and the northern Apulian coast (Gulf of Manfredonia) on the opposite sides of the South Adriatic Sea. The plankton was collected from 14 stations. A total of 188 categories were recognized in plankton samples. Among those categories, 130 species were recognized (87 of phytoplankton, 43 of microzooplankton), and only 53 (40.8%) resulted common to both the Adriatic sides. A total of 69 cyst morphotypes were recognized in sediment samples; 38 of them were classified at the level of species. A statistical analysis of the micro-zooplankton species abundance showed a segregation of the two areas better than that obtained with the phytoplankton. Cyst distribution in the sediments showed a good gulf-segregation too. In addition, they allowed us to find complementary information, particularly for dinoflagellates. The most abundant species in the water column were not equally dominant as resting stages in the sediments. Sediment sampling allowed further information about the composition of the plankton communities, and suggested us to search for a new method to enhance the yield of less abundant cysts.     

欧洲绿色交通发展经验

首先探索了绿色交通涉及的因素,指出可持续交通层面下的政策目标。对实现这些目标可以采取的相关策略进行分析,包括新技术的应用以及交通政策的干预。基于欧洲经验,总结了交通政策的效果和作用,包括土地利用、基础设施、交通管理、运营措施、信息和宣传、费用等。最后,针对实施交通战略过程中存在的体制、可接受性、财政三方面的阻碍提出建议。     

Erosion-corrosion damages of water-pump impeller

A steel impeller placed in a water pump has been studied with the aim of understanding the surface erosion-corrosion phenomena responsible for reducing the pumping efficiency of water inside the cooling system. This experiment includes long-term (over about half a year) observations with a powered microscope and precise weight measurements. The experiments were carried out under different conditions of water using several mixtures of water and coolants with water contents of 25%, 50%, 75%, and 100% (i.e., pure tap water). The visual microscopy results reveal that most of the steel surface is pitted and clearly rusty, such that corrosion phenomena are noticeable as time passes. In addition, the amount of weight lost from the sample specimens submerged in static water increased linearly, whereas those placed in mixtures of water and coolant initially gained weight before reaching an almost constant weight. In order to see the dynamic effect of the impeller on the erosion-corrosion phenomena, surface observations of the steel impeller were also made at each time after suitable running conditions in water and water-coolant mixtures, namely around 3∼4 hours of operation per day under changing rotation speeds. The results show that the rate of weight loss was linear and 2∼3 times higher than the impeller in water under both static and dynamic conditions. However, when the impeller was submerged in the mixtures, the weight loss was initially insignificant due to the corrosion-proof ingredients of the coolant, but after around 2 months the weight loss substantially increased and gradually approached a linear curve.     

Torsion beam axle system design with a multidisciplinary approach

This research proposes an automatic torsion beam axle optimization process with a multidisciplinary approach and generates the optimal torsion design parameters, such as thickness and shape. In order to construct an automatic analysis process, multidisciplinary analysis models, such as modal analysis, roll mode dynamic analysis, and fatigue analysis, were applied in batch mode. To understand the design space, a parametric study using the torsion beam thickness and shape was performed. Considering roll durability and K&C characteristics, the torsion beam axle could be optimized. For the automated design process, a PIDO tool called PIAnO was used. In conclusion, a reduction in the computer-aided simulation time was achieved, and the durability and K&C characteristics of the torsion beam were enhanced by optimizing the thickness and shape.     

Online license plate matching procedures using license-plate recognition machines and new weighted edit distance

License-plate recognition (LPR) technology has been widely applied in many different transportation applications such as enforcement, vehicle monitoring, and access control. Recently, there has been effort to exploit an LPR database for vehicle tracking using popular template matching procedures. Existing template matching procedures assume that the true reference string is always available. However, under a two-point LPR survey, a vehicle could have its plate misread at both locations generating a pair of misread strings (or templates) with no reference for matching. To compensate for LPR misreading problem, we propose a new weight function based on a probability model to match the observed outcomes of a dual LPR setup. Also, considering that reversal errors are never made in LPR machines, new editing constraints as a function of the string lengths are proposed to avoid compensation for reversal errors. These editing constraints are incorporated into the constraint edit distance formulation to improve the performance of the matching procedure. Finally, considering that previous template matching procedures do not take advantage of passage time information available in LPR databases, we present an online tracking procedure that considers the properties of probability distribution of vehicle journey times in order to increase the probability of correct matches. Experimental results show that our proposed procedure can improve the accuracy of LPR systems and achieve up to 97% of positive matches with no false matches. Further research is needed to extend the ideas proposed herein to plate-matching with multiple, i.e., more than two, LPR units.     

Evaluate bus emissions generated near far-side and near-side stops and potential reductions by ITS: An empirical study

In this paper, we use second-by-second automatic vehicle location data to estimate bus emissions near far-side and near-side stops. We classify the bus running state near a stop into approach, dwell, and departure. A vehicle specific power approach is used to estimate bus emissions for each state. We show that bus emissions generated near stops can be significantly reduced by using certain intelligent transportation systems techniques.     

High‐speed rail cost recovery time based on an integer optimization model

With increasing gasoline prices, electric high‐speed rail (HSR) systems represent one means to mitigate overexposure to volatile prices. However, additional research is needed related to funding this infrastructure. In this paper, we develop a new integer optimization model to address this problem and use a hypothetical case study to demonstrate the approach. The objective of the approach is to minimize the time period in which the cost of HSR construction and operation can be recovered. This is an iterative process based on an integer optimization model, whose objective function is to determine the optimum recovery time (ORT), by setting the HSR ticket price and frequency. Embedded in the optimization model is a multinomial logit model for calculating the demand for HSR as a function of these decision variables, thus capturing the effects of level of service on market share. In particular, the optimization model accounts for the role of different types of subsidies toward HSR construction (one‐time subsidies at construction, annual subsidies, and subsidies depending on frequency). This method can also help determine whether an HSR system should be built or how much subsidy should be provided given a fixed expected cost recovery time. By integrating the logit model into the objective function evaluation, the effects of ticket price and service frequency on service demand can be directly captured. Copyright © 2014 John Wiley & Sons, Ltd.     

Social inclusivity through public transportation: a strategic approach to improve quality of life in developing countries

Welfare services such as healthcare and education are commonly recognised as determinants of physical quality of life indices during the early phases of development in the third world. In order to benefit from these services, it is important that the general public have the mobility means to access welfare provision centres. However, very low vehicle ownership under the conditions of low per‐capita incomes and large shares of population living in deep rural areas prevent the masses from accessing such services, thereby retarding the process of social development, which is reflected in the very poor physical quality of life indices in low‐income countries. Public transportation could offer a viable and affordable solution to this apparent ambivalence. It could permit mobility for poor masses in spite of low per‐capita vehicle ownership enabled by the national income levels. The present research demonstrates this strategic niche through an econometric examination of the evolution of the physical quality of life indices such as maternal mortality, infant mortality and literacy as against the healthcare, education and affordable mobility proxies in post‐independent Sri Lanka. The country, which was then referred to as Ceylon, is often cited as a rare example of achieving social inclusion and reduced marginalisation and thereby a high social welfare standing, in spite of relatively poor per‐capita income levels. Copyright © 2015 John Wiley & Sons, Ltd.     

绕Wigley船自由表面粘性流场计算

本文采用商用粘性流场求解软件COMET计算带自由液面绕Wigley船的粘性流动,网格数约为216000。计算中使用标准k-ε湍流模式和壁函数。用HRIC算法确定自由面。同时域步进法得到稳态解,计算的在傅氏数为0.30时的阻力结果与模型试验测量值吻合良好。预报的船体周围的波型及船体表面的波面形状也较合理。     

Water masses and cyclonic circulation in Bay of La Paz, Gulf of California, during June 1998

The Bay of La Paz, a coastal and shallow basin of the Gulf of California (depth<420 m), exchanges mixed-layer waters with the Gulf of California predominantly through Boca Grande (Big Mouth), in the northeastern part of the bay. Equatorial Surface Water (ESW) flows from the gulf to the bay; once there, due to evaporation processes, this water increases its salinity above 35.00, therefore becoming Gulf of California Water (GCW) Mass. During June 1998, the baroclinic circulation in the bay was dominated by a cyclonic gyre. The hydrographic dome, related to this gyre, is depicted until approximately 150-m depth. However, the vertical mixing of water between the mixed-layer and the ones below practically does not occur because of the development of a sharp pycnocline. This fact and the isolation of the bottom of the bay by a bathymetric sill (approximately 250-m depth) at Boca Grande induce low oxygen content, particularly in the bottom-waters (O₂<0.1 ml/l). Chlorophyll values are higher and with larger vertical fluctuations within the Bay of La Paz than outside.