Gazing Geometries: Modes of Design Thinking in Pre-Modern Central Asia and Persian Architecture

The architecture of the pre-modern Islamic world broadly identifies itself with geometric design. In erecting buildings, architects-engineers of the Islamic world utilized distinct modes of geometric projections vital to the spatial conception of the building. These representations identify three modes of design drawings: plans, revetments/vertical surfaces, and reflected ceiling plans. This paper will discuss these modes of drawings and their unique role in relation to the architectural “design thinking” traditions. Much has been examined regarding two-dimensional Islamic geometric patterns (girih), but little exists in terms of a comprehensive framework investigating various modes of geometric drawings in relation to formal, spatial, and tectonic conceptions of the architectural space. This paper fills a critical gap in the literature about Islamic architecture and examines this topic through primary resources and original pamphlets.     

In situ, noninvasive characterization of superhydrophobic coatings

Light scattering was used to measure the time-dependent loss of air entrapped within a submerged microporous hydrophobic surface subjected to different environmental conditions. The loss of trapped air resulted in a measurable decrease in surface reflectivity and the kinetics of the process was determined in real time and compared to surface properties, such as porosity and morphology. The light-scattering results were compared with measurements of skin-friction drag, static contact angle, and contact-angle hysteresis. The in situ, noninvasive optical technique was shown to correlate well with the more conventional methods for quantifying surface hydrophobicity, such as flow slip and contact angle.     

Theoretical Prediction With Numerical and Experimental Verification to Predict Crosswind Effects on the Performance of Cooling Towers

A simple theoretical model, validated against available numerical and experimental data in the literature, is presented to predict the effects of crosswind on the performance of natural draft dry cooling towers. The intersection of asymptote method, along with scale analysis, is used to find a closed-form solution for the airflow rate at the tower exit for given crosswind speeds. The total heat rejected under a windy condition is then calculated based on the air mass flow rate at the tower exit. This theoretical model allows for parametric studies and can generate accurate data. Interestingly, the model results, expected to be accurate within an order of magnitude, are more accurate than anticipated when compared to available experimental and numerical data in the literature. In fact, the maximum relative error is observed to be 15% when current theoretical predictions are compared to available experimental data. The results of this study will be useful for future work on the development of air-cooled condensers, especially for geothermal and solar thermal power plants in Australia.     

Mining fleet management systems: a review of models and algorithms

The objective of this paper is to review and document the mine fleet management systems’ models and algorithms. The purpose is to understand the algorithms behind the fleet management systems and the proposed academic solutions in this area to identify any gaps in the current literature and to open up opportunities to establish research questions that need to be addressed in an integrated simulation and optimisation operational planning research framework. In this paper, we review industrial fleet management systems and the main academic algorithms behind such systems. The fleet management systems are divided into three subsequently related problems to review: shortest path, production optimisation and real-time dispatching. Finally, the limitations of current algorithms for fleet management systems are documented in terms of mining practice feasibility and optimality of the solution on large-scale problems. The results of this literature review enable us to evaluate the logical links between major components of an integrated simulation and optimisation operational planning framework with current theory of fleet management systems.     

Dynamic shovel allocation approach to short-term production planning in open-pit mines

The complexity and uncertainties associated with mining operations often lead to deviations from short-term plans. A proactive approach will predict such deviations and help minimise opportunity losses, providing economic and operational gains. This paper presents an optimisation tool as a dynamic shovel allocation decision-maker for mining operation simulation models. The objectives of the optimisation tool are to provide shovel allocations to mining faces in order to maximise production, meet desired head grade and tonnage at the crushers, and minimise shovel movements. This paper presents the development and implementation of the optimisation tool with an iron ore mine case study.     

Adsorption Characteristics of Congo Red from Aqueous Solution onto Tea Waste

The feasibility of using tea waste (TW) as a low-cost adsorbent for the adsorption of an anionic dye (Congo red) from aqueous solution has been investigated. Adsorption in a batch process was conducted to study the effect of adsorbent dosage, initial dye concentration, contact time, pH, and temperature. The experimental data were analyzed by the Langmuir, Freundlich, and Temkin models. The adsorption system was best described by the Langmuir isotherm (R ² > 0.99). Adsorption kinetics followed a pseudo-second-order model (R ² > 0.99). The effect of mechanical treatment (vibratory mill) was also studied. The experimental results showed that using this physical treatment leads to an increase in the adsorption capacity of TW from 32.26 to 43.48 mg/g. Thermodynamic analyses revealed that the adsorption of Congo red on TW was endothermic and spontaneous in nature. The results indicated that TW can be employed as a potential low-cost adsorbent for the removal of Congo red from aqueous solution.     

Evaluation of most similar neighbour and random forest methods for imputing forest inventory variables using data from target and auxiliary stands

We report the results from modelling standing volume, above-ground biomass and stem count with the aim of exploring the potential of two non-parametric approaches to estimate forest attributes. The models were built based on spectral and 3D information extracted from airborne optical and laser scanner data. The survey was completed across two geographically adjacent temperate forest sites in southwestern Germany, using spatially and temporally comparable remote-sensing data collected by similar instruments. Samples from the auxiliary reference stands (called off-site samples) were combined with random, random stratified and systematically stratified samples from the target area for prediction of standing volume, above-ground biomass and stem count in the target area. A range of combinations was used for the modelling process, comprising the most similar neighbour (MSN) and random forest (RF) imputation methods, three sampling designs and two predictor subset sizes. An evolutionary genetic algorithm (GA) was applied to prune the predictor variables. Diagnostic tools, including root mean square error (RMSE), bias and standard error of imputation, were employed to evaluate the results. The results showed that RF produced more accurate results than MSN (average improvement of 3.5% for a single-neighbour case with selected predictors), yet was more biased than MSN (average bias of 5.13% with RF compared to 2.44% with MSN for stem volume in a single-neighbour case with selected predictors). Combining systematically stratified auxiliary samples from the target data set with the reference data set yielded more accurate results compared to those from random and stratified random samples. Combining additional data was most influential when an intensity of up to 40% of supplementary samples was appended to the reference set. The use of GA-selected predictors resulted in reduced bias of the models. By means of bootstrap simulations of RMSE, the simulations were shown to lie within the applied non-parametric confidence intervals. The achieved results are concluded to be helpful for modelling the mentioned forest attributes by means of airborne remote-sensing data.     

An Efficient Numerical Scheme to Solve a Quintic Equation of State for Supercritical Fluids

In this study, an efficient iterative algorithm is devised to handle a nonlinear equation arising in estimation of thermodynamic properties at supercritical conditions. The approach is based on a synergistic combination of the classic Newton-Raphshon algorithm and the Adomian decomposition method. We demonstrate that the proposed method enjoys a higher degree of accuracy while requiring fewer iterations to reach a specific solution compared to that by the Newton-Raphson algorithm. To illustrate the efficiency of the aforementioned solution technique, several numerical examples are provided. The proposed method has been easily implemented in computer codes to provide parametric, not just numeric, solutions to the model equations. Consequently, one can derive other thermodynamic properties, which have not been treated parametrically to date, based on our new combined approach.     

Schools and skills of critical thinking for urban design

This paper explores possible ways in which urban design can engage with critical thinking and critical theory. After a brief explanation of the terms, with particular attention to the Frankfurt School of thought, it provides various answers to the question as to whether urban design is critical or not. One categorization applied to planning critical theory is then used to explain the potential for employing critical theories in urban design. Critical thinking skills are then argued to be helpful for enriching the literature of urban design in order to achieve better practice. The conclusion is that urban design can benefit from critical creativity, which is an embodiment of critical thinking within the limits imposed onto creativity. In this paper, the ways in which urban design can engage with both critical theory and with critical thinking are explored in order to achieve better critical creativity in the field.     

高速数据转换器接口

数据转换器的复杂性随着采样频率及精度的提高而增加。高性能的数据转换器规格的设定必须遵循严格的输入条件,以实现器件预期性能的最大化。一个颇具挑战性的输入条件是:对ADC输入模拟信号进行测量、驱动和接口连接。本文将探讨一些对高速ADC进行有效接口连接的技术,从而使ADC实现性能最佳化。