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Among the different nanostructures that have been demonstrated as promising materials for various applications, three–dimensional (3D) nanostructures have attracted significant attention as building blocks for constructing high-performance nanodevices because of their unusual mechanical, electrical, thermal, optical, and magnetic properties arising from their novel size effects and abundant active catalytic/reactive sites due to the high specific surface area. Considerable research efforts have been devoted to designing, fabricating, and evaluating 3D nanostructures for applications, including structural composites, electronics, photonics, biomedical engineering, and energy. This review provides an overview of the nanofabrication strategies that have been developed to fabricate 3D functional architectures with exquisite control over their morphology at the nanoscale. The pros and cons of the typical synthetic methods and experimental protocols are reviewed and outlined. Future challenges of fabrication of 3D nanostructured materials are also discussed to further advance current nanoscience and nanotechnology.

Natural silk fiber derived from the Bombyx mori (B. mori) silkworm has long been used as a luxury raw material in textile industry because of its shimmering appearance and durability, and as surgical suture for its high strength and flexibility. Regenerated silk fibroin, as the main protein extracted from the cocoons of the B. mori silkworm, recently has gained considerable attention due to its outstanding properties, including facile processability, superior biocompatibility, controllable biodegradation, and versatile functionalization. Tremendous effort has been made to fabricate silk fibroin into various promising materials with controlled structural and functional characteristics for advanced utilities in a multitude of biomedical applications, flexible optics, electronics devices, and filtration systems. Herein, reverse engineered silk fibroin extraction methods are reviewed, recent advances in extraction techniques are discussed. Fabrication methods of silk fibroin materials in various formats are also addressed in detail; in particular, progress in new fabrication technologies is presented. Attractive applications of silk fibroin-based materials are then summarized and highlighted. The challenges faced by current approaches in production of silk fibroin-based materials and future directions acquired for pushing these favorable materials further toward above mentioned applications are further elaborated.

Acoustic/elastic metasurfaces as a kind of two-dimensional metamaterials are of subwavelength thickness and show remarkable ability of acoustic/elastic wave manipulation. They have potential applications in various fields such as acoustic imaging, communications, cloaking, camouflage, vibration/noise control, energy harvesting, and nondestructive testing. In this review, we mainly summarize recent developments in acoustic/elastic phase gradient metasurfaces, including design principles, design of functional elements, wave field manipulation with applications, design of tunable metasurfaces, as well as the emerging digital coding metasurfaces. At last, we outline the future research directions in this field.

A series of experiments were carried out aiming at resource utilization of fresh green waste and sewage sludge. The green waste, rice straw and sewage sludge were chosen as raw materials and packing materials in composting experiments to study the variation characteristics of composting in different aeration patterns. It was found that the effect of intermittent aeration pattern during composting was better than continuous aeration pattern according to the results of detection of composting temperature, oxygen, carbon dioxide.

Measure the temperature of exterior window and surrounding walls’ inner surface, and measure interior air temperature to analyze the effect, which was brought to building energy consumption and interior thermal conditions by the exterior window of the building; studied several details of exterior window design, and proposes a method, which is separately controlling the heat-transfer coefficient according to different orientation, room’s positions and room’s functions while designing the exterior windows, in order to improve the interior thermal conditions and reduce energy consumption of the residential buildings.

The dynamical-wave method routing model of the unsteady and non-pressure rain pipe flow was be established by conservation of mass, momentum and energy in the city unsteady and non-pressure rain pipe flow, and it was resoled by applying the four concealing style differences and the pursue method. Results by experiment checking computations and comparative analysis state that this routing model can reflect flood peak propagate in pipeline attenuate and backwater etc. influence, has high calculation precision, possess vast sphere of application, and can adapt to performing the city rain pipe flow routing in the distinct situation of the different incline degrees and enter runoff. This routing model supplies the scientific foundation to the town rainfall piping design or checking, administration of storm runoff, and so on.

Through improving the real-coded genetic algorithms and embedding the algorithm of accelerating the local search in the Powell direction and the operation of accelerating cycle, thereby it is constructed the New blend Accelerating Genetic Algorithm (hereinafter referred to as NBAGA). The applied examples of the calibration on nonlinear single return period storm intensity model parameters show that this method takes into account of the advantages of both the advantages of the improved real-coded genetic algorithms and the Powell Algorithm, therefore this method is an excellent nonlinear optimization method which can search the global optimal exact solutions quickly and in greater probability, as well as doing subtle search locally.

Using the Fluent software, the flow field of oxidation ditch was simulated by the three dimensional turbulence mathematical model. The velocities were analyzed and measured, and the simulation results showed acceptable prediction of the velocities in the oxidation ditch. The results also showed that velocity could reach more than 0.3m/s when 8 impellers worked, and MLSS in the whole ditch were almost uniform, therefore, the oxidation ditch runs well.

Most of the past studies about dealership market involved only one monoplistic market-maker. The paper aims to build an artificial financial market based on multiple competitive market makers on ANYLOGIC platform, in which one market-maker adopts BAYES learning rule to estimate the fundamental value and the other employs a rough method. In order to validate the effectiveness of dealers’ quotes, we carried out two group simulation experiment. The results show that the quote of each dealer can converge to the fundamental value with certain deviation. What’s more, the deviation of the market-maker with learning ability is smaller while the converging speed slower.

One-switch utility function is used to describe how the risk attitude of a decision maker changes with his wealth level. In this paper additive decision rule is used for the aggregation of decision member’s utility which is represented by one-switch utility function. Based on Markov decision processes (MDP) and group utility, a dynamic, multi-stages and risk sensitive group decision model is proposed. The proposed model augments the state of MDP with wealth level, so the policy of the model is defined as an action executed in a state and a wealth level interval. A backward-induction algorithm is given to solve the optimal policy for the model. Numerical examples show that personal risk attitude has a great influence on group decision-making when personal risk attitudes of members are different, while the weights of members play a critical role when personal risk attitudes of members are similar.

Artificial boundary is an important part of finite element calculation model. Based on finite element method, this paper presents substructure condensation elements to simulate far field boundary. As most dynamic responses are focused on ground surface, substructure elements’ internal nodes are condensed and only keep the nodes on the ground surface to maintain the accuracy of scattering wave transmition. According to the example of verification, if the related parameters are chosen properly, the effect of substructure condensation boundary is guaranteed.

Deep soil mixing techniques have been widely adopted in China since the late 1970s and mainly used for ground improvement for structural support and earth-retaining structures for excavations. A comprehensive state-of-practice review on development, applications, soil-cement properties, mechanistic studies, design methods, and quality control of deep soil mixing techniques in China is presented. These research results will serve as a reference for advancing deep soil mixing techniques in the United States and other countries.

Deep soil mixing techniques have been widely adopted in China since the late 1970s and mainly used for ground improvement for structural support and earth-retaining structures for excavations. A comprehensive state-of-practice review on development, applications, soil-cement properties, mechanistic studies, design methods, and quality control of deep soil mixing techniques in China is presented. These research results will serve as a reference for advancing deep soil mixing techniques in the United States and other countries.