Adapting the light · biomass (BZI) models of phytoplankton primary production to shallow marine ecosystems

Several authors have reported a strong linear relationship between daily phytoplankton production and the product of chlorophyll biomass, photic depth, and incident irradiance for a variety of estuaries. This “light · biomass” (BZ_pI_o) formulation has been proposed as an alternative to traditional mechanistic approaches for computing phytoplankton production in numerical estuarine models. One limitation to their application in shallow systems is that the BZ_pI_o models have been developed in relatively deep estuaries where light does not reach the bottom. We propose a nonlinear correction factor to adapt the BZ_pI_o relationship to shallow systems where light does reach the bottom. Our function takes into account variations in incident irradiance, attenuation coefficient for light, photosynthetic efficiency, and maximum rate of photosynthesis. A series of correction polynomials are proposed for various ranges of incident irradiance, and are integrated into a single multiple polynomial which applies across all irradiance levels. Our new correction factor was tested against a ¹⁴C-based productivity dataset from shallow stations in Narragansett Bay, RI and an O₂-based dataset from shallow (1.1 m) lagoon mesocosms at the University of Rhode Island. Results showed that our polynomials accurately correct BZ_pI_o-predicted rates of production in shallow water columns. Application of our correction factor to a series of shallow water productivity datasets from the literature together with theoretical calculations show how significant the shallow water correction can be, especially in very shallow water columns with low turbidity.     

Study of in-vehicle route guidance systems for improvement of right-side drivers in the Japanese traffic system

A country can adopt one of two standards for traffic flow — cars may travel on the left or right side of the road. When drivers who are accustomed to driving on the right side of the road drive on the left side, and vice versa, the mental workload is likely increased due to the driver’s unfamiliarity with a new language, the position of the driver’s seat, different driving directions, and other factors that differ from those of their home country. One method of doing this is to make sure that the in-vehicle route guidance information (RGI) is not overly complicated — thereby assisting drivers in improving their safety. Consequently, the aim of this study was to facilitate mobility and improve safety for natural right-side drivers driving temporarily in left-side traffic. In this study, driver behavior and workload — given various types of RGI — were evaluated in a driving simulator with a variety of prescribable test conditions. This research was composed of two experiments. In the first, various types of in-vehicle route guidance systems were tested and evaluated in terms of their characteristics and associated driver behaviors (while driving). In the second experiment, systemic factors and effectiveness were evaluated by two combined systems, arrow and map-type information, based on the results of the first experiment. In light of both experiments, the various types of route guidance systems were discussed in terms of their results. A navigation system was proposed to alleviate some of the secondary tasks such as route selection.     

HBeAg特异免疫复合物检测及临床意义

采用单克隆抗－ＨＢｅ固相ＥＬＩＳＡ法检测１１８例ＨＢＶ感染者血清中ＨＢｅＡｇ特异免疫复合物（ＨＢｅＡｇ／ＩＣ），结果表明∶ＨＢｅＡｇ／ＩＣ与ＨＢＶ复制相关，可作为ＨＢＶ复制的一种血清学标志，ＨＢｅＡｇ阴性、ＨＢＶＤＮＡ阳性者中，６２．２％患者ＨＢｅＡｇ／ＩＣ阳性，提示ＨＢｅＡｇ／ＩＣ的形成致使夹心法不能检出ＨＢｅＡｇ，这类患者仍可以是ＨＢＶ野毒株感染，并非均为ＨＢｅＡｇ缺陷变异株感染；ＨＢｅＡｇ／ＩＣ阳性血清ＡＬＴ异常率明显高于ＨＢｅＡｇ／ＩＣ阴性血清（Ｐ＜０．０１），提示ＨＢｅＡｇ／ＩＣ存在与肝损伤有关。     

基于多点源沥青混合料同步供应与摊铺的施工监理研究

常规沥青混合料供应都是一个拌合站供料,上海A15公路因建设任务紧、工作量大,故采用多个拌合站同时供应一个摊铺点的操作方式。该文从配合比设计及前场摊铺施工等几个方面阐述了多点源的差异性控制要点,保证了沥青混合料的级配、色泽外观一致。     

Torque characteristics analysis for optimal design of a copper-layered eddy current brake system

An enhanced parametric model for a copper-layered eddy current electric machine (retarder) is introduced in this paper. The modeled torque characteristics of the copper-layered electromagnetic retarders are based on the results from a detailed electromagnetic finite element analysis (FEA) of these eddy current machines. The model uses a parameterized double-exponential function to model the steady state speed-torque characteristics of the retarder. The parameters are adjusted for optimal braking performance in conjunction with predicted speed-torque characteristics of a copper-layered retarder. A full vehicle model, along with the proposed retarder speed-torque model has been used to simulate a series braking events. The simulation results show that the peaks of the retarder speed-torque curves must be designed to occur within a specific range of speeds for optimal braking performance.     

Topological analysis of powertrains for refuse-collecting vehicles based on real routes–Part I: Hybrid hydraulic powertrain

In this two-part paper, a topological analysis of powertrains for refuse-collecting vehicles (RCVs) based on the simulation of different architectures (internal combustion engine, hybrid electric, and hybrid hydraulic) on real routes is proposed. In this first part, a characterization of a standard route is performed, analyzing the average power consumption and the most frequent working points of an internal combustion engine (ICE) in real routes. This information is used to define alternative powertrain architectures. A hybrid hydraulic powertrain architecture is proposed and modelled. The proposed powertrain model is executed using two different control algorithms, with and without predictive strategies, with data obtained from real routes. A calculation engine (an algorithm which runs the vehicle models on real routes), is presented and used for simulations. This calculation engine has been specifically designed to analyze if the different alternative powertrain delivers the same performance of the original ICE. Finally, the overall performance of the different architectures and control strategies are summarized into a fuel and energy consumption table, which will be used in the second part of this paper to compare with the different architectures based on hybrid electric powertrain. The overall performance of the different architectures indicates that the use of a hybrid hydraulic powertrain with simple control laws can reduce the fuel consumption up to a 14 %.     

Optimal scheduling of the flexray static segment based on two-dimensional bin-packing algorithm

FlexRay is a reliable and hard real-time in-vehicle communication protocol that is strongly promoted by car manufacturers as the de facto standard in the automotive domain. The protocol offers both a time-triggered and an eventtriggered architecture. This paper focuses on the optimal scheduling of the time-triggered component of FlexRay known as the static (ST) segment using a two-dimensional bin-packing technique. To maximize the bandwidth utilization in the ST segment, a fast heuristic as well as an efficient integer linear programming approach are proposed. Our methods directly schedule signals into slots including frame packing, according to signal-based data scheduling and the slot/ cycle multiplexing mechanisms presented by the latest version of the FlexRay protocol. The benefits of our proposed methods are demonstrated by extensive experiments on synthetic and an automotive X-by-wire system case study. An additional test case is examined to emphasize the superior performance of the proposed approach relative to that of existing optimal scheduling approaches.     

发展我国铁路短途旅客运输的策略

立足我国铁路短途旅客运输市场发展状况,就客运量变化、旅客运输需求特点、客运周转量、运输收入、运输距离增长变化等进行分析;将国外铁路与我国铁路短途客运运价水平进行比较,并计算我国铁路近年客运量的价格弹性;介绍国外铁路发展短途旅客运输营销方式与策略,提出我国铁路短途旅客运输发展建议。     

摩托车用数字式CDI点火器

根据点火储能元件的不同，点火器主要有电容充放电点火（ＣＤＩ）和晶体管点火（ＴＣＩ）两种类型。介绍了摩托车用数字式ＣＤＩ的工作原理及软、硬件结构。其突出的优点在于能够根据预先给定的进角曲线对发动机点火提前角进行精确控制，从而使发动机在各种工作转速范围内均能够达到最佳性能。