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To enhance the carbonation reactivity of wollastonite (CS), three different calcination processes were adopted to synthesis CS with different crystal structures. The effects of the cooling process on the polymorphs, carbonation reactivity, and CO2 sequestration capacity of CS were measured and evaluated, and its carbonation hardening properties and microstructure evolution were also explored. The results indicated that the carbonation reactivity of CS was enhanced by the rapid cooling process due to the inhibition of the polymorphic transition of α-CS to β-CS. The enhanced carbonation reactivity was attributed to the distorted CaOx polyhedra and extended Ca-O distance in α-CS, which made the dissolution of α-CS to leach Ca2+ easier. The CO2 sequestration capacity and compressive strength of highly reactive CS reached 27.2% and 92.3 MPa, respectively, after carbonation for 24 h. Therefore, it was demonstrated that highly reactive CS can be adopted as ultra-low calcium and CO2 sequestration binder.

There is an urgent demand for privacy-preserving techniques capable of supporting compute and data intensive (CDI) computing in the era of big data. However, none of existing TEEs can truly support CDI computing tasks, as CDI requires high throughput accelerators like GPU and TPU but TEEs do not offer security protection of such accelerators. This paper present HETEE (Heterogeneous TEE), the first design of TEE capable of strongly protecting heterogeneous computing with unsecure accelerators. HETEE is uniquely constructed to work with today's servers, and does not require any changes for existing commercial CPUs or accelerators. The key idea of our design runs security controller as a stand-alone computing system to dynamically adjust the boundary of between secure and insecure worlds through the PCIe switches, rendering the control of an accelerator to the host OS when it is not needed for secure computing, and shifting it back when it is. The controller is the only trust unit in the system and it runs the custom OS and accelerator runtimes, together with the encryption, authentication and remote attestation components. The host server and other computing systems communicate with controller through an in memory task queue that accommodates the computing tasks offloaded to HETEE, in the form of encrypted and signed code and data. Also, HETEE offers a generic and efficient programming model to the host CPU. We have implemented the HETEE design on a hardware prototype system, and evaluated it with large-scale Neural Networks inference and training tasks. Our evaluations show that HETEE can easily support such secure computing tasks and only incurs a 12.34% throughput overhead for inference and 9.87% overhead for training on average., Comment: 16 pages, 7 figures

In order to solve the problems of high labor intensity, low efficiency, and unstable cleaning quality when cleaning optical pipelines with traditional manual high-pressure spray, automatic cleaning equipment with high pressure water jet for optical pipelines is designed. The working principle and the design points are introduced. The movement rule of the nozzle under self-propelled drive is analyzed by ANSYS, the results show that the self-propelled drive cannot meet the cleaning speed requirements. Therefore, the wire rope driving method is proposed to realize the control of the nozzle speed. Subsequently, the speed of the simulated water jet is analyzed by the STARCCM, it is inferred that the water jet is still in the basic section at the maximum target distance of the pipeline, which can be used for cleaning. For verifying the cleaning effect, the prototype is applied to the cleaning of the actual optical pipelines. The verification results show that the cleaning equipment can meet the requirements of 100 / class clean, and the efficiency is increased by 70% compared with the traditional manual high-pressure spray.

The influences of colloidal nanoBoehmite (CNB) and colloidal nanoSiO 2 (CNS) on fly ash cement mortar hydration and microstructure development of fly ash cement pastes were investigated. The results revealed that fly ash cement hydration was accelerated by CNB and CNS at early age thus enhancing the early age strength of the materials. Although higher content of nanoparticles significantly hindered cement hydration, adding appropriate amount of CNB and CNS benefited the development of compressive strength both at early and later age.

Phase change materials (PCMs) have been widely applied to develop building materials with high thermal energy storage capacity. In this study, the capric acid–palmitic acid (CA–PA)/expanded perlite (EP) composite PCM was prepared using vacuum impregnation method and the thermal-regulated gypsum boards were fabricated by adding the prepared composite PCM. Scanning electron microscope images revealed that the CA–PA eutectic mixture was uniformly distributed in pores of EP and the CA–PA/EP composite PCM has a little effect on the interface gypsum crystals growth. Differential scanning calorimeter results showed that the melting temperature range of the composite PCM was 24.1–31 °C and the latent heat was 88.39 J g −1 . The composite PCM had a good chemical stability by surveying the chemical characterization of the composite PCM. Furthermore, the heat transfer property, thermal conductivity, bending and compressive strength were also tested. The results indicated that the higher the composite PCM volume content, the smaller the thermal conductivity of the gypsum board and the lower the temperature fluctuation in the cubicle system. The bending strength and compressive strength reduced gradually with an increase of the volume fraction of the composite PCM.

Nanomaterial, as a new emerging material in the field of civil engineering, has been widely utilized to enhance the mechanical properties of cementitious material. Nano-SnO2 has presented high hardness characteristics, but there is little study of the application of nano-SnO2 in the cementitious materials. This study mainly investigated the hydration characteristics and strength development of Portland cement paste incorporating nano-SnO2 powders with 0%, 0.08%, and 0.20% dosage. It was found that the early-age compressive strength of cement paste could be greatly improved when nano-SnO2 was incorporated with 0.08% dosage. The hydration process and microstructure were then measured by hydraulic test machine, calorimeter, nanoindentation, X-ray diffraction, scanning electron microscope, and mercury intrusion porosimetry. It was found that the cement hydration process was promoted by the addition of nano-SnO2, and the total amount of heat released from cement hydration is also increased. In addition, the addition of nano-SnO2 can promote the generations of high density C-S-H and reduce the generations of low density C-S-H indicating the nucleation effect of nano-SnO2 in the crystal growth process. The porosity and probable pore diameter of cement paste with 0.08% nano-SnO2 were decreased, and the scanning electron microscopic results also show that the cement paste with 0.08% nano-SnO2 promotes the densification of cement microstructure, which are consistent with the strength performance.

Chinese medical theory and complexity theory are two distinct bodies of knowledge concerned with the nature and behavior of natural systems. The former is an artifact from mankind's ancient past; the latter is a vanguard of contemporary science. Yet the basic principles and modes of thinking in these two subjects can be productively compared and employed to make connections between ideas and individuals from apparently disparate backgrounds. These connections may provide insights to all involved. This paper presents some basic comparisons and explores potential ways to begin to construct links between a millennia-old method of traditional medicine and methodologies that lie at the frontiers of modern scientific knowledge. Topics addressed include: the dilemma facing modern Western medicine, the methodology of Chinese medicine, relationships between Chinese medicine and complexity theory, keys to further research, including: language and terminology, analysis of medicinal formulas, analysis of diagnostic and therapeutic principles and procedures, and the application of the metaphoric mode of thinking of Chinese medicine to the investigation of complex adaptive systems. Finally, there is a statement of principles that should be borne in mind by researchers in development of detailed guidelines and criteria for the design of studies and the evaluation of results.

The paper proposes a method to measure vibration amplitude of ultrasonic horn which is a very important component in the spindle for micro-electrical-chemical discharging machining. The method of image measuring amplitude on high frequency vibration is introduced. Non-contact measurement system based on vision technology is constructed. High precision location algorithm on image centroid, quadratic location algorithm, is presented to find the center of little light spot. Measurement experiments have been done to show the effect of image measurement technique on vibration amplitude of ultrasonic horn. In the experiments, precise calibration of the vision system is implemented using a normal graticule to obtain the scale factor between image pixel and real distance. The vibration amplitude of ultrasonic horn is changed by modifying the voltage amplitude of pulse power supply. The image of feature on ultrasonic horn is captured and image processing is carried out. The vibration amplitudes are got at different voltages.

The generalized eigenproblem of a linear gyroscopic system with a non-positive definitive stiffness matrix K is derived based on the state vector method. The expansion theorem for an arbitrary state vector and the weighted adjoint symplectic orthogonality between eigenvectors are also proved in the paper. By using the symplectic LDLT factorization, the generalized eigenproblem is reduced to the standard form of symplectic eigenproblem of skew-symmetric matrices. The symplectic orthogonal transformations are then used to tri-diagonalize the coefficient matrix for the solutions of eigenvalues and eigenvectors which is the central part of modal analysis for gyroscopic systems.

In this paper, we prove thatχ(Seqξ)=d, when ξ is Frechet filter orP-point in ω* withx(ξ,ω*)≤d.