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It is an indispensable part of airworthiness certification to evaluate the fuel tank flammability exposure time for transport aircraft. There are many factors and complex coupling relationships affecting the fuel tank flammability exposure time. The current work not only lacks a comprehensive analysis of these factors but also lacks the significance of each factor, the interaction relationship and the prediction method of flammability exposure time. The lack of research in these aspects seriously restricts the smooth development of the airworthiness forensics work of domestic large aircraft. This paper aims to clarify the internal relationship between user input parameters and predict the flammability exposure time of fuel tanks for transport aircraft.

Based on the requirements of airworthiness certification for large aircraft, an in-depth analysis of the Monte Carlo flammability evaluation source procedures specified in China Civil Aviation Regulation/FAR25 airworthiness regulations was made, the internal relationship between factors affecting the fuel tank flammability exposure time was clarified and the significant effects and interactions of input parameters in the Monte Carlo evaluation model were studied using the response surface method. And the BP artificial neural network training samples with high significance factors were used to establish the prediction model of flammability exposure time.

The input parameters in the Monte Carlo program directly or indirectly affect the fuel tank flammability exposure time by means of the influence on the flammability limit or fuel temperature. Among the factors affecting flammability exposure time, the cruising Mach number, balance temperature difference and maximum range are the most significant, and they are all positively correlated with flammability exposure time. Although there are interactions among all factors, the degree of influence on flammability exposure time is not the same. The interaction between maximum range and equilibrium temperature difference is more significant than other factors. The prediction model of flammability exposure time based on multifactor interaction and BP neural network has good accuracy and can be applied to the prediction of fuel tank flammability exposure time.

The flammability exposure time prediction model was established based on multifactor interaction and BP neural network. The limited test results were combined with intelligent algorithm to achieve rapid prediction, which saved the test cost and time.

The purpose of this paper is to explore the moderating effect of brand exposure time and exposure frequency in image transfer. In study 1, H1 and H2 assumed the bidirectional image transfer (i.e. from an event to a brand, from a brand to an event). H3 and H4 were set to examine the moderating effect of brand exposure time and exposure frequency in image transfer upon spreading activation theory, mere exposure effect and three-hit theory.

According to study 1, the result indicated that the amount of image transfer varied based on the exposure time. However, brand exposure frequency did not show statistically significant interactions. Study 2 was performed to complement the H4 of the study 1. In study 2, apart from the number of exposures on a screen (group 1=four times; group 2=eight times), the perceived number of exposures were separately measured (group 1=2.67; group 2=3.96) to see if the number of perceived exposures moderated the amount of image transfer.

The results indicated that there was no group difference in the amount of image transfer. Based on the result of the study, a sponsor brand must be exposed for enough time duration in order to maximize the return on investment regardless of how frequently it is exposed.

The current study examined the image transfer in sport sponsorship. Although previous studies empirically examined the image transfer phenomenon in sport sponsorship, they failed to establish theoretical ground. Thus, this study incorporated the three theories in advertising and examined how we can apply the theories to sport sponsorship. In addition, we examine the image transfer based on video clip which is mainly how people are exposed to sport sponsorship. Next, we examined the moderating effects of exposure duration and exposure frequency, which has never been studied in sport sponsorship context.

The assessment of fuel tank flammability exposure time for transport aircraft is one of the indispensable links in the airworthiness certification process. According to published literature, many factors can affect the flammability exposure time, while systematic analysis and calculations addressing these factors are in shortage.

Based on the requirements for airworthiness certification of domestic large aircraft, the fuel tank flammability exposure time of transport aircraft is calculated with the Monte Carlo evaluation model specified by Federal Aviation Administration. Meanwhile, the influence of each input parameter on the flammability exposure time is obtained by taking user input parameters in the model as independent variables and freezing other factors at the same time. The significance degree of the influence of each factor is discussed by the orthogonal test method. Subsequently, the interaction between the input parameters is studied by response surface method, and a multiple linear regression method is used to establish the functional relationship between the flammability exposure time and the influence parameters.

Research studies show that among the many factors that affect the flammability exposure time, the cruising Mach number, the equilibrium temperature difference and the maximum range are more significant and much attention should be paid to in the airworthiness certification; although there are interactions among various factors, they have different influence on the flammability exposure time, among which the interactions between maximum range and equilibrium temperature difference are the most significant compared with others; established by applying multiple linear regression equation and based on the test data of response surface method, the functional relationship between flammability exposure time and influence parameters is of sufficient reliability and can be used for preliminary prediction of fuel tank flammability exposure time for transport aircraft.

The research achievements of this paper can provide much useful reference for the certification of domestic large aircraft.

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative information technology open architecture design and integrating Radio Frequency Identification Device data technologies and real-time optimization and control mechanisms as the critical technology components of the solution. The innovative information technology, which pursues the focused logistics, will be deployed in 36 months at the estimated cost of $568 million in constant dollars. We estimate that the Systems, Applications, Products (SAP)-based enterprise integration solution that the Army currently pursues will cost another $1.5 billion through the year 2014; however, it is unlikely to deliver the intended technical capabilities.

Many process parameters in selective laser melting (SLM) can be configured to optimize build time, which directly relates to energy consumption, and to achieve acceptable part quality. This study aims to investigate whether energy can be effectively reduced with acceptable mechanical properties. The influence of exposure time is primarily focused to correlate energy consumption to mechanical properties.

Through single-factor design and experiment result analysis, three levels of exposure time were examined in fabricating two sets of sample parts, for energy analysis and mechanical property tests. Manufacturing power profile was measured online, and four mechanical properties, tensile, flexural, torsional strengths and part density, were investigated. A graphical growth rate tendency (GRT) plot is proposed to jointly analyze multiple variables.

Energy consumption increases in fabricating a same part with the increase of exposure time in the tested range, but exposure time was found to influence build power rather than build time in the given SLM system. Mechanical properties do not increase linearly, and grow at different rates. It is found that within the tested range, increased energy consumption brought to a small improvement of part density, but a notable improvement of tensile strength and maximum torque.

Producing quality SLM parts can be energy-effective through quantitative study. The proposed GRT plot is an intuitive visual aid to compare the growth rates of different variables, which offers more information to additive manufacturing practitioners.

In this research, energy consumption and mechanical property are jointly analyzed for the first time to advance the knowledge of energy-effective SLM fabrication. This helps additive manufacturing technology to be truly energy-efficient and environmental-friendly.

The purpose of this paper is to provide some insights into the exchange rate exposure of Australian stock returns.

Using a dynamic econometric approach that allows for both asymmetry and time‐varying risk exposures in both the exchange rate variable and the market variable, a large sample of Australian firms were tested over the period of January 2001 and December 2005. The data were analysed using three different classification methods, forming portfolios according to industry sector, size deciles, and censoring deciles.

Although the evidence of exchange rate exposure is limited across the sample of industries, the following were found: a time‐varying asymmetric effect primarily in the utilities sector, time‐varying exposure in the materials and energy sectors, and an asymmetric effect in the technology sector. Further, some time‐varying asymmetric exchange rate exposure was found across most size and censoring deciles and also substantial evidence of a positive asymmetric effect in the market beta across all three classification methods.

This approach varies from previous studies in this area that only allow for asymmetry and time variation in exchange rate exposures. The paper also examines the Australian stock market, a market which has not been extensively tested in this area of empirical research.

This paper aims to reduce the cost, limit the time and increase raw material source availability, coral aggregate seawater concrete (CASC) composed of coral, coral sand, seawater and cement can be widely used for the construction of ports, levees, airports and roads to achieve practical engineering values. However, the naturally porous coral structure and abundant Cl⁻ in the seawater and coral lead to extremely severe reinforcement corrosion for CASC. It is well known that Cl⁻ is the main cause of reinforcement corrosion in the marine environment. Therefore, it is necessary to research the reinforcement corrosion of CASC in the marine environment.

In this study, linear polarization resistance was adopted to test the linear polarization curves of reinforcement in CASC with different exposure times. E_corr, R_p, I_corr and V_corr were calculated according to the weak electrochemical polarization theory and Stern–Geary formula. The effects of concrete cover thickness, exposure time, reinforcement types and inhibitor on reinforcement corrosion in CASC were analysed. The reinforcement corrosion degradation rule was determined, which provided theoretical support for the durability improvement, security assessment, service life prediction and service quality control of CASC structures in marine islands and reef engineering.

The corrosion resistance was enhanced with increased concrete cover thickness, and the concrete cover thickness for organic new coated steel should be at least 5.5 cm to reduce the reinforcement corrosion risks in CASC structures. The corrosion resistance of different types of reinforcements followed the rule: 2205 duplex stainless steel > 316 stainless steel > organic new coated steel > zinc-chromium coated steel > common steel. In the early exposure stage, the anti-corrosion effectiveness of the calcium nitrate inhibitor (CN) was superior to that for the amino alcohol inhibitor (AA). With the extension of exposure time, the decreasing rate of anticorrosion effectiveness of CN was higher than that of AA.

Reinforcement corrosion of CASC in a marine environment was studied. Concrete cover thickness, exposure time, reinforcement type and inhibitor influenced the reinforcement corrosion were investigated. New technique of reinforcement anti-corrosion in marine engineering was proposed. Possible applications of CASC in marine engineering structures were suggested.

Exposure controlled projection lithography (ECPL) is an additive manufacturing process based on controlled UV photopolymerization. This paper aims to explore an advanced closed-loop control methodology to ECPL.

This paper proposes an evolutionary cycle to cycle (EC2C) control method, and started with a reduced order EC2C time control to control only the exposure time for given DMD bitmaps, which correspond to target 3D part cross-sections. A preliminary EC2C time control scheme was developed and followed by two types of EC2C time controllers based on two different parameter estimation methods, recursive least squares and L₁ norm minimization (L₁Min). Both algorithms were in an exponential weighted form, resulting in EWRLS and EWL₁Min, to weight more on recent data to reflect the current process dynamics.

EWRLS was found to outperform EWL₁Min in terms of computation speed and stability. The simulation study demonstrated that the proposed EC2C time control method was capable of adaptively tracking the ECPL process dynamics and updating online the model parameters with real-time measurements. It could control perfectly the exposure time for each bitmap, achieving the desired height for each layer and resulting in a total cured height conforming to the target 3D part height.

The accuracy of EC2C time control method relies heavily on fast and accurate measurement, and this research assumes availability of an adequate real-time metrology. Measurement errors are not considered in this paper and will be explored in future. Only simulation study was performed without physical experiments to verify the EC2C controller.

For implementation, a real-time measurement system needs to be developed and the EC2C control software needs to be programmed and interfaced with the physical system.

It concludes that EC2C control method is very promising for a physical implementation, and could be extended for the development of a more comprehensive closed-loop controller for both exposure time and intensity to improve the ECPL process precision and robustness.

The purpose of the paper is to investigate photochemical machining characteristics of stainless steel (AISI 304-SS304) parts with a novel design are investigated experimentally from the aspect of process parameters. The effects of phototool pattern geometry, ultraviole (UV) exposure time and etching time on of AISI 304 were evaluated.

The designed semi-automated photochemical manufacturing (PCM) equipment consists of 4 units, which include UV exposure, etching, developing and surface cleaning units. Experimental procedure has been designed via Taguchi method. Results were evaluated via Analysis of Variance (ANOVA) method.

Etching time is the most effective factor in PCM quality of AISI 304 stainless steel. Surface roughness is sensitive to geometrical pattern of the phototool for PCM of AISI 304 UV exposure time is less influential on the PCM quality for stainless steel.

The designed PCM equipment prototype is not fully automated, which requires automation for part replacements into units. The effects of the temperature inside chemical processing units on process characteristics cannot be evaluated due to equipment limitations. The effects of surface cleaning time inside surface cleaning unit are not analyzed.

The utilized PCM equipment is semi-automated equipment, with which the process parameters such as etching time, surface cleaning time, UV exposure time and developing time can be controlled. Different from literature, the effects of phototool pattern geometries on the photochemical machining quality parameters are evaluated for the processing of AISI 304. The effects of processing parameters on dimensional accuracy, which is not common in the literature for AISI 304 stainless steel, are also evaluated.

The thermal history during laser exposure determines part properties in selective laser sintering (SLS). The purpose of this study is to introduce a new measurement technique based on a CO₂ laser unit combined with a high-speed DCS. A first comparison of the thermal history during laser exposure measured with Laser-high-speed-(HS)-differential scanning calorimetry-(DSC) and in SLS process is shown.

This Laser-HS-DSC allows an imitation of the SLS-process in a very small scale, as the sample is directly heated by a CO₂ laser. For this study, the laser power and the impact time is varied for determining temperature and achieved heating rates. Consequently, the temperature levels measured by the Laser-HS-DSC are compared with measurements in SLS-process.

The influence of laser power and impact time on resulting maximum temperatures und heating rates during laser exposure are investigated. With increasing laser power and impact time the maximum temperature rises up to approximately 450°C without material degradation. The heating rate increases up to an impact time of 3 ms and stays almost equal for higher durations.

The Laser-HS-DSC experiments are based on few particles limiting a complete comparison with SLS process. In SLS, one volume element is exposed several times. In this study the PA12 material was exposed only once.

For the first time, laser sintering experiments can be transferred to a laboratory scale to analyze the influence of laser exposure on resulting temperature field during laser exposure without superimposing effects.