The marine electronic highway in the Straits of Malacca and Singapore—an assessment of costs and key benefits

The Straits of Malacca and Singapore are an important trade route linking the Indian Ocean to the South China Sea and Pacific Ocean. They are also rich in resources and support a range of activities that benefit the economies of the littoral states (Indonesia, Malaysia and Singapore). This important shipping route is a very congested waterway and the authorities are keen to improve navigation facilities to promote ship safety and reduce the risk of groundings, collisions and accidents. This will also help to protect the marine environment from the effects of pollution and hence reduce its damaging impact on activities related to the Straits, e.g. fisheries and tourism. The Marine Electronic Highway (MEH) is an attempt to bring together maritime safety technologies and environmental management systems. The paper examines the costs of providing such a highway and considers some of the benefits which could accrue from its implementation. The analysis, conducted in the form of a cost-benefit study, clearly shows the economic viability of the scheme.     

Gain and noise figure analysis of Er<Superscript>3+</Superscript>-doped YAG transparent ceramic microchip amplifier

The rate equations and the power evolution equations based on excited state absorption (ESA) and cooperative upconversion (CUC) of high concentration erbium-doped yttrium aluminum garnet (YAG) transparent ceramic waveguide amplifier are set up to analyze the effects of the pump power, active ion concentration and waveguide length on the amplifier gain and noise figure (NF). The numerical analysis predicts that with a pump power of 100mW, an active ion concentration of 1.0×10²⁶ ion/m³ and a waveguide length of 3 cm, a small-signal gain of 30 dB and an NF of 5 dB can be achieved in the micro-chip amplifier.     

Study of the helicopter blade running elevation measurement system

Helicopter blade running elevation measurement is an important measure target in helicopter blade dynamic balance experimentation. The elevation influences the helicopter＇ s security and other performance capabilities. In testing, however, it has been difficult to measure the elevation when the rotor reaches high speeds. To get a simple, fast and highly accurate measurement system, photo electricity technology was applied to measuring the blade running elevation. Discussed is the measurement principle of blade running elevation, tire design of the measurement system and analysis of the measurement precision.     

Course-keeping control of underactuated hovercraft

The course-keeping control of underactuated hovercraft with two aft propellers was considered. The control of the heading error and cross-track error was accomplished by the yaw torque merely in this case. The hovercraft dynamic model is nonlinear and underactuated. At first the Controllability of course-keeping control for hovercraft was proved, then a course-keeping control law was derived that keeps hovercraft heading constant as well as minimizes the lateral movement of hovercraft. The proposed law guarantees heading error and sway error all converge to zero exponentially. Simulation tests were carried out to illustrate the effectiveness of the proposed control law. For further research, the disturbance influence would be considered in the dynamic equations.     

Special requirements for alumina ceramic of ESG electrode bowl

At present ESG (Electrostatic Suspended Gyro) is the most precise inertia element in the world. The electrode bowl, which has direct effect on the precision of ESG, is a key part to ESG. Through the analysis of the function and characteristic of the electrode bowl in hollow rotor ESG and the present situation of new material development in the world, the alumina ceramic is regarded as the best material for the electrode bowl of hollow rotor ESG. By analyzing the present situation of alumina ceramic in the world, main technique requirements have been put forward for the alumina ceramic of ESG electrode bowl which is also fit for solid rotor ESG.     

金融危机下，导航企业怎样生存

虽然金融危机爆发已经好几个月了,但真正的危机将在2009年春节后到来,现在只不过是个“危机预热期”。在此情况下,我们的导航地图业如何保持业绩持续增长,在危机期间凸显新兴行业的潜力呢？     

Gasket life criteria at low temperatures adopting proportional compensation for loss of flexibility and conformability

In the automobile industry, the service life of gaskets is defined as the time until which a released gasket recovers 60 % of the original compression. It was observed that the recovery curves of gaskets were highly nonlinear at high temperatures, and relatively nonlinear at temperatures above the room temperature. However, it was also noted that the recovery curves of the gaskets at temperatures below room temperature exhibited linearity with respect to the ln(time). Automotive manufacturers demand gasket life criteria that exceed a specific time or the entire life of a car. In the case of gaskets used at lower temperatures, since materials encounter losses in its flexibility and conformability, the definition of service life specifying a 60 % recovery may not be sufficiently safe to eliminate possible leakages. In this study, new gasket life criteria that could be used at low temperatures were proposed. The new criteria were proposed based on the change in Young’s modulus of the gasket material in order to conserve the sealing capability.     

Performance Design of an Exhaust Superheater for Waste Heat Recovery of Construction Equipment

Although fuel cost has been the largest portion of annual operating costs of construction equipment, it is possible to save the energy and reduce cost using fuel economy enhancement technology. In this study, an organic Rankine cycle is applied to an excavator in order to recover waste heat, reproduce it into electrical energy, and consequently reduce the fuel consumption by 10 %. A design process was carried out to develop an exhaust gas superheater that recovers the waste heat from exhaust gas through a composite-dimensional thermal flow analysis. A one-dimensional code was developed to perform a size design for the exhaust gas superheater. The ranges for the major design parameters were determined to satisfy the target of the heat recovery, as well as the pressure drop at both fluid sides. Performance analysis was done through onedimensional design code results, which were compared with three-dimensional CFD analysis. By utilizing a 3D commercial code, the arrangement of the tubes was selected and the working fluid pressure drop was reduced through a detailed layout design. The design procedure was verified by a performance evaluation of the prototype, which yielded only a 7 % tolerance in heat recovery.