Estimating cost of equity in project discount rates using the capital asset pricing model and Gordon’s wealth growth model

Since the 2008 global financial crisis, mining projects have to invariably compete for scarce capital under depressed market conditions. The discounted cash flow analysis commonly used for the valuation of mining projects relies on using a discount rate. However, an appropriate discount rate is sometimes the subject of contestation since factors such as the stage of development of the mineral project affect the rate. This paper independently tests the reliability of capital asset pricing model and Gordon’s wealth growth model estimates of cost of equity in discount rates and concludes that Gordon’s wealth growth model provides better estimates under depressed market conditions.     

现代城市中“负空间”类型与对策概述

存在于城市中的负空间是在建筑物之间起着过渡与衔接作用的空间,是设计师在定义了各种功能空间之后所遗漏的空间,也是藏有各种消极因素与隐患的空间。该文按照其不同的位置和特点对负空间的种类做了归纳与分析,并且从设计层面上提出了多个改善的要点与策略,有助于降低消极负空间的影响,提升城市空间质量与居住舒适度。     

Bacterial communication systems: A mathematical formulation of negative chemotaxis

The emergence of molecular communication (MC) has provided a new paradigm for communication at nanoscale, besides the electromagnetic one. Numerous biological systems have been proposed that could be used for communication, using mostly bacteria as information carriers, ensuring biocompatibility and low complexity requirements. In this work, message dissemination dynamics in a bacterial communication system was under investigation by means of a simulation framework that was designed and developed based on a commercial tool. A mathematical formulation is proposed, in an effort to accurately predict the system's behavior under the presence of chemotactic‐like nodes. Simulation results are in strong agreement with the respective mathematical model, for a wide range of biological processes, including phenomena such as chemotaxis, bacterial growth cycle, and biological message transformation dynamics. In the case of a simple simulation scenario exhibiting chemotaxis, the mean accuracy improvement reaches values of up to 19% .     

Effect of heating rate on the recrystallization microstructure and property of ultra-low-carbon steel

In the present work,the microstructure,texture,and mechanical properties of a cold-rolled Ti-IF steel, after annealing at different heating rates,have been investigated.The results reveal that the mean grain size is gradually refined from19.2 to 16.3μm as the heating rate increases from4 to50℃/s,but refined only slightly at heating rates of over 50 ℃/s.The recrystallization microstructure has a strong texture,which is a result of the sharpening of the favorable{111}//ND(normal direction)texture components orγ-fiber.With increasing heating rates,the peak value of f(g)ofγ-fiber decreases from17 to9.The yield and tensile strengths increase gradually as the heating rate increases from4 to 50℃/s,but remain almost unchanged at heating rates of more than 50℃/s. The total elongation and uniform elongation increase gradually as the heating rate increases from4to100℃/s,but decreases slowly for heating rates higher than100℃/s.As the heating rate increases from4to100℃/s,the plastic strain ratio of the steel decreases from2.8to2.2;however,it increases to2.9for heating rates above100℃/s.The strain hardening exponent remains unchanged at 0.27in all annealing cycles.     

Joint Hadamard transform and Alamouti scheme for wireless communication system

In this letter, the joint of Hadamard transform and Alamouti scheme is proposed. By applying Hadamard transform in the Alamouti scheme, two points of constellation can be merged into one symbol. This symbol is used for input of Alamouti scheme without changing the behavior of Alamouti scheme. System model for joint Hadamard transform and Alamouti scheme is also suggested and formulated. Simulation results show that the bit error rate (BER) performance of the proposed scheme outperforms the original Alamouti scheme.     

砂率对混凝土主要性能的影响分析

在参阅国内外文献的基础上,结合混凝土配合比设计过程中的一点经验,论述了砂率对混凝土主要性能的影响,提出了确定合理砂率的原则。     

Novel hybrid Monte Carlo/deterministic technique for shutdown dose rate analyses of fusion energy systems

The rigorous 2-step (R2S) computational system uses three-dimensional Monte Carlo transport simulations to calculate the shutdown dose rate (SDDR) in fusion reactors. Accurate full-scale R2S calculations are impractical in fusion reactors because they require calculating space- and energy-dependent neutron fluxes everywhere inside the reactor. The use of global Monte Carlo variance reduction techniques was suggested for accelerating the R2S neutron transport calculation. However, the prohibitive computational costs of these approaches, which increase with the problem size and amount of shielding materials, inhibit their ability to accurately predict the SDDR in fusion energy systems using full-scale modeling of an entire fusion plant. This paper describes a novel hybrid Monte Carlo/deterministic methodology that uses the Consistent Adjoint Driven Importance Sampling (CADIS) method but focuses on multi-step shielding calculations. The Multi-Step CADIS (MS-CADIS) methodology speeds up the R2S neutron Monte Carlo calculation using an importance function that represents the neutron importance to the final SDDR. Using a simplified example, preliminary results showed that the use of MS-CADIS enhanced the efficiency of the neutron Monte Carlo simulation of an SDDR calculation by a factor of 550 compared to standard global variance reduction techniques, and that the efficiency enhancement compared to analog Monte Carlo is higher than a factor of 10,000.     

A new compact circuit-level model of semiconductor lasers: investigation of relative intensity noise and frequency noise spectra

We introduce a new compact noise equivalent circuit model of semiconductor lasers (SLs) from the rate equation including Langevin noise sources. The noise sources are described in terms of the spectral properties of the relative intensity noise (RIN) and frequency/phase noise (FN). Unlike the previous noise equivalent circuit models, which are based on two different DC and small-signal circuit models, using only a single circuit model, the static and dynamic responses and also the noise characteristics of SLs, can be investigated. We examine the validity of the presented noise circuit model by comparing the simulated results with the analytical and numerical results available in the literatures.     

浅谈预制装配式住宅在上海的发展

预制装配式住宅是区别于当前传统住宅的一种新型建筑体系模式,是未来实现低碳方式、绿色施工的途径.预制装配式住宅的运用体现了可持续发展的理念,然而预制装配式住宅在经过了5年大张旗鼓的发展之后,现在进入了一个相对平缓的阶段,甚至可以说是到了发展的瓶颈阶段,本文将就预制装配式住宅发展困难的原因作简要分析.