Intelligent Window Research Articles

Dual-intelligent windows regulating both solar and long-wave radiations dynamically

Advanced energy-efficient windows have been widely investigated due to the special role of windows among building envelopes. Here, we propose an idea of dynamic management of both solar radiation and long-wave thermal radiation. A window based on this idea can be named as a dual-intelligent window, which blocks the solar radiation as well as emits little long-wave thermal radiation to the indoor side during hot daytime and cools the room by dissipating heat from the indoor side to the outdoor side through radiative heat transfer at cool nights. Based on the properties of thermochromic vanadium dioxide (VO2), it was found that a dual-intelligent window can be accomplished by pasting the VO2 film onto the indoor side of the window. The energy performance of this conceptual dual-intelligent window was numerically simulated and compared with low-emissivity window and traditional VO2 window where the VO2 film is on the outdoor side. The results show that the window with low emissivity cannot reduce the energy consumption for cooling due to the lack of the ability of regulating the long-wave thermal radiation. The dual-intelligent window surpasses the traditional intelligent VO2 windows due to the fact that the application of the dual-intelligent window can reduce cooling energy by 21.7% compared with the traditional intelligent window. This improvement of dual-intelligent window emphases the advantages of dynamically regulating solar and long-wave radiations simultaneously.

Augmented Reality-assisted Intelligent Window for Cyber-Physical Machine Tools

Aiming to advance current machine tools to a higher level of intelligence and autonomy, this paper presents a new generation of machine tools, i.e. Cyber-Physical Machine Tool (CPMT), inspired by the recent advances in Cyber-Physical Systems (CPS). CPMT refers to a CPS-enabled machine tool that integrates physical machine tool and machining processes with computation and networking capabilities. Augmented Reality (AR) is used to enable intuitive and efficient human-machine interactions between humans and CPMT. An AR-assisted Intelligent Window for CPMT is proposed. The Intelligent Window is essentially an advanced Human-Machine Interface (HMI) which provides users with intuitive interactions with CPMT. The proposed Intelligent Window consists of four main functional modules, Real-time Control, AR-enabled Process Monitoring, AR-enabled Machining Simulation, and Process Optimization. An AR-assisted Intelligent Window for an EMCO Concept 105 milling machine is developed making use of a touch-screen computer. The advantages and potentials of CPS and AR in manufacturing are discussed based on the experience gained from the experiments.

Anti-biofouling function of amorphous nano-Ta2O5 coating for VO2-based intelligent windows

From environmental and health perspectives, the acquisition of a surface anti-biofouling property holds important significance for the usability of VO2 intelligent windows. Herein, we firstly deposited amorphous Ta2O5 nanoparticles on VO2 film by the magnetron sputtering method. It was found that the amorphous nano-Ta2O5 coating possessed a favorable anti-biofouling capability against Pseudomonas aeruginosa as an environmental microorganism model, behind which lay the mechanism that the amorphous nano-Ta2O5 could interrupt the microbial membrane electron transport chain and significantly elevate the intracellular reactive oxygen species (ROS) level. A plausible relationship was established between the anti-biofouling activity and physicochemical nature of amorphous Ta2O5 nanoparticles from the perspective of defect chemistry. ROS-induced oxidative damage gave rise to microbial viability loss. In addition, the amorphous nano-Ta2O5 coating can endow VO2 with favorable cytocompatibility with human skin fibroblasts. This study may provide new insights into understanding the anti-biofouling and antimicrobial actions of amorphous transition metal oxide nanoparticles, which is conducive to expanding their potential applications in environmental fields.

ZnO MESFETS for application to Intelligent Windows

ZnO MESFETS for application to Intelligent Windows

Formation energies of intrinsic point defects in monoclinic VO2 studied by first-principles calculations

VO2 is an attractive candidate for intelligent windows and thermal sensors. There are challenges for developing VO2-based devices, since the properties of monoclinic VO2 are very sensitive to its intrinsic point defects. In this work, the formation energies of the intrinsic point defects in monoclinic VO2 were studied through the first-principles calculations. Vacancies, interstitials, as well as antisites at various charge states were taken into consideration, and the finite-size supercell correction scheme was adopted as the charge correction scheme. Our calculation results show that the oxygen interstitial and oxygen vacancy are the most abundant intrinsic defects in the oxygen rich and oxygen deficient condition, respectively, indicating a consistency with the experimental results. The calculation results suggest that the oxygen interstitial or oxygen vacancy is correlated with the charge localization, which can introduce holes or electrons as free carriers and subsequently narrow the band gap of monoclinic VO2. These calculations and interpretations concerning the intrinsic point defects would be helpful for developing VO2-based devices through defect modifications.

Controllable Broadband Optical Transparency and Wettability Switching of Temperature-Activated Solid/Liquid-Infused Nanofibrous Membranes.

Inspired by biointerfaces, such as the surfaces of lotus leaves and pitcher plants, researchers have developed innovative strategies for controlling surface wettability and transparency. In particular, great success has been achieved in obtaining low adhesion and high transmittance via the introduction of a liquid layer to form liquid-infused surfaces. Furthermore, smart surfaces that can change their surface properties according to external stimuli have recently attracted substantial interest. As some of the best-performing smart surface materials, slippery liquid-infused porous surfaces (SLIPSs), which are super-repellent, demonstrate the successful achievement of switchable adhesion and tunable transparency that can be controlled by a graded mechanical stimulus. However, despite considerable efforts, producing temperature-responsive, super-repellent surfaces at ambient temperature and pressure remains difficult because of the use of nonreactive lubricant oil as a building block in previously investigated repellent surfaces. Therefore, the present study focused on developing multifunctional materials that dynamically adapt to temperature changes. Here, we demonstrate temperature-activated solidifiable/liquid paraffin-infused porous surfaces (TA-SLIPSs) whose transparency and control of water droplet movement at room temperature can be simultaneously controlled. The solidification of the paraffin changes the surface morphology and the size of the light-transmission inhibitor in the lubricant layer; as a result, the control over the droplet movement and the light transmittance at different temperatures is dependent on the solidifiable/liquid paraffin mixing ratio. Further study of such temperature-responsive, multifunctional systems would be valuable for antifouling applications and the development of surfaces with tunable optical transparency for innovative medical applications, intelligent windows, and other devices.

Oxidative stress-mediated selective antimicrobial ability of nano-VO2against Gram-positive bacteria for environmental and biomedical applications

Vanadium dioxide (VO2) is a unique thermochromic material as a result of its semiconductor-metal transition, holding great promise for energy-saving intelligent windows. Herein, pure nano-VO2 from discrete nanoparticles to continuous films were successfully deposited on quartz glass by controlling the sputtering parameters. It was demonstrated that, for Gram-positive S. aureus and S. epidermidis, the nano-VO2 could effectively disrupt bacteria morphology and membrane integrity, and eventually cause death. By contrast, the nano-VO2 did not exhibit significant toxicity towards Gram-negative E. coli and P. aeruginosa. To our knowledge, this is the first report on a selective antimicrobial effect of nano-VO2 materials on Gram-positive bacteria. Based on the experimental results, a plausible mechanism was proposed for the antimicrobial selectivity, which might originate from the different sensitivity of Gram-positive and Gram-negative bacteria to intracellular reactive oxygen species (ROS) level. Elevated intracellular ROS levels exceed the threshold that bacteria can self-regulate to maintain cellular redox homeostasis and thus cause oxidative stress, which can be alleviated by the intervention of glutathione (GSH) antioxidant. In addition, nano-VO2 did not produce significant cytotoxicity (hemolysis) against human erythrocytes within 12 h. Meanwhile, potential cytotoxicity against HIBEpiC revealed a time- and dose-dependent behavior that might be controlled and balanced by careful design. The findings in the present work may contribute to understanding the antimicrobial behavior of nano-VO2, and to expanding the new applications of VO2-based nanomaterials in environmental and biomedical fields.

Use of ZnO as antireflective, protective, antibacterial, and biocompatible multifunction nanolayer of thermochromic VO2 nanofilm for intelligent windows

A multifunctional VO2/ZnO bilayer film is designed and deposited by magnetron sputtering apparatus. The integration of the antireflective, antioxidative and anti-corrosion functions, and antibacterial performance makes the heterostructure film a promising candidate in the energy-saving smart window. The ZnO thin film as the antireflection layer can markedly boost the solar regulation efficiency (ΔTsol) from 7.7% to 12.2% and possesses excellent luminous transmittance (Tlum-L=50.3%) in the low-temperature semiconductor phase. The ZnO layer as the protection barrier can not only protect VO2 thin film from oxidation to much toxic V2O5, but also decrease the release of V ions. Besides, the synergistic effect of releasing killing by Zn2+ ions and contact killing by ZnO NPs makes ZnO thin film an outstanding antibacterial coating. In terms of the biological safety, ZnO coating with appropriate film thickness can effectively attenuate the cytotoxicity of VO2 on human HIBEpiC cells. We hope this work can provide new insights for better designing of novel multifunctional VO2-based intelligent energy-saving windows.

Optical properties of a thin layer of the Vanadium dioxide at the metal state

The vanadium dioxide VOâ‚‚ currently became very motivating for the nanotechnologies’ researchers. It makes party of the intelligent materials because these optical properties abruptly change semiconductor state with metal at a critical  temperature θ = 68°C. This transition from reversible phase is carried out from a monoclinical structure characterizing its semiconductor state at low temperature towards the metal state of this material which becomes tétragonal rutile for  θ ˃ 68°C ; it is done during a few nanoseconds. Several studies were made on this material in a massive state and a thin layer. We will simulate by Maple the constant optics of a thin layer of VOâ‚‚ thickness z = 82 nm for the metal state according to the energy ω of the incidental photons in the energy interval: 0.001242 ≤ ω(ev) ≤ 6, from the infra-red (I.R) to the ultra-violet (U.V) so as to be able to control the various technological nano applications, like the detectors I.R or the U.V, the intelligent windows to increase  the energy efficiency in the buildings in order to save the cost of energy consumption by electric air-conditioning and the paintings containing nano crystals of this material. The constant optics, which we will simulate, is: the index of refraction, the reflectivity, the transmittivity, the coefficient of extinction, the dielectric functions ԑ₁ real part and  ԑ₂ imaginary part of the permittivity complexes Ô‘ of this material and the coefficient absorption.Â

An effective and intelligent Windows application filtering system using software similarity

As licensed programs are pirated and illegally spread over the Internet, it is necessary to filter illegally distributed or cracked programs. The conventional software filtering systems can prevent unauthorized dissemination of the programs maintained by their databases using an exact matching method where the feature of a suspicious program is the same as that of any program stored in the database. However, the conventional filtering systems have some limitations to deal with cracked or new programs which are not maintained by their database. To address the limitations, we design and implement an efficient and intelligent software filtering system based on software similarity. Our system measures the similarity of the characteristics extracted from an original program and a suspicious one (or, a cracked one) and then determines whether the suspicious program is a cracked version of the copyrighted original program based on the similarity measure. In addition, the proposed system can handle a new program by categorizing it using a machine learning scheme. This scheme helps an unknown program to be identified by narrowing the search space. To demonstrate the effectiveness of the proposed system, we perform a series of experiments on a number of executable programs under Microsoft Windows. The experimental results show that our system has achieved comparable performance.

The potential cytotoxicity and mechanism of VO2 thin films for intelligent thermochromic windows

The potential cytotoxicity of a thermochromic VO2 nanofilm to human cells presumably originates from ATP dyssynthesis by vanadate-phosphate antagonism.

The acidic transformed nano-VO2 causes macrophage cell death by the induction of lysosomal membrane permeabilization and Ca2+ efflux

Because of its outstanding thermochromic characteristics and metal-insulator transition (MIT) property, nano-vanadium dioxide (abbreviated as nano-VO2 or nVO2) has been applied widely in electrical/optical devices and design of intelligent window. However, the biological effect of nVO2 is not well understood, especially when affected by environmental factors or living organisms. For VO2 is an amphoteric oxide, we simulated pH's influence to nVO2’s physicochemical properties by exposure nVO2 in water of different pH values. We found that nVO2 transformed to a new product after exposure in acidic water for two weeks, as revealed by physicochemical characterization such as SEM, TEM, XRD, and DLS. This transformation product formed in acidic water was referred as (acidic) transformed nVO2). Both pristine/untransformed and transformed nVO2 displayed no obvious toxicity to common epithelial cells; however, the acidic transformed nVO2 rapidly induced macrophage cell death. Further investigation demonstrated that transformed nVO2 caused macrophage apoptosis by the induction of Ca2+ efflux and the following mitochondrial membrane permeabilization (MMP) process. And a more detailed time course study indicated that transformed nVO2 caused lysosomal membrane permeabilization (LMP) at the earlier stage, indicating LMP could be chosen as an earlier and sensitive end point for nanotoxicological study. We conclude that although nVO2 displays no acute toxicity, its acidic transformation product induces macrophage apoptosis by the induction of LMP and Ca2+ efflux. This report suggests that the interplay with environmental factors or living organisms can results in physicochemical transformation of nanomaterials and the ensuing distinctive biological effects.

지능적인 RFID 미들웨어 시스템을 위한 적응형 윈도우 슬라이딩 기반의 유연한 데이터 정제

Over the past years RFID/SN has been an elementary technology in a diversity of applications for the ubiquitous environments, especially for Internet of Things. However, one of obstacles for widespread deployment of RFID technology is the inherent unreliability of the RFID data streams by tag readers. In particular, the problem of false readings such as lost readings and mistaken readings needs to be treated by RFID middleware systems because false readings ultimately degrade the quality of application services due to the dirty data delivered by middleware systems. As a result, for the higher quality of services, an RFID middleware system is responsible for intelligently dealing with false readings for the delivery of clean data to the applications in accordance with the tag reading environment. One of popular techniques used to compensate false readings is a sliding window filter. In a sliding window scheme, it is evident that determining optimal window size intelligently is a nontrivial important task in RFID middleware systems in order to reduce false readings, especially in mobile environments. In this paper, for the purpose of reducing false readings by intelligent window adaption, we propose a new adaptive RFID data cleaning scheme based on window sliding for a single tag. Unlike previous works based on a binomial sampling model, we introduce the weight averaging. Our insight starts from the need to differentiate the past readings and the current readings, since the more recent readings may indicate the more accurate tag transitions. Owing to weight averaging, our scheme is expected to dynamically adapt the window size in an efficient manner even for non-homogeneous reading patterns in mobile environments. In addition, we analyze reading patterns in the window and effects of decreased window so that a more accurate and efficient decision on window adaption can be made. With our scheme, we can expect to obtain the ultimate goal that RFID middleware systems can provide applications with more clean data so that they can ensure high quality of intended services.

Design of Power Windows Based on POWERLINK Industrial Ethernet

This paper proposes a design of intelligent control system power windows based on POWERLINK bus by introducing features and advantages of POWERLINK bus technology. The system implements the real-time communication between each control unit and central controller through the POWERLINK bus, largely enhancing the coordination of window lift control, improving security features such as anti-pinch and has good scalability and portability.

Study on the Spectral Distribution Property of PDLC Films Color Display

PDLC films are very useful materials and can apply in flexible displays, intelligent switchable windows, information storage and adaptive optical devices. In this paper we focus on its color display characteristic in reflective display and firstly we fabricated PDLC films by polymerization induced phase separation method and measured its transmissivity and spectral reflection curves of the printing ink layer and PDLC covered color by X-Rite DTP41 Spectrophotometer. From the result, it demonstrates that PDLC films show different optical transmission properties in long and short wavelength.

Design of Intelligent Windows Based on Power Line Carrier and GPRS Communication Technology

Aiming at the problem of traditional windows need manual operation, intelligent windows system based on power line carrier (PLC) and GPRS wireless communication technology was designed. The system used PLC technology realize the establishment of the internal network; Used varieties of sensors as peripheral detection devices and data acquisition equipment, transmitted collected data to central controller through the power line; Used ARM9 embedded processor S3C2440A as center controller; Used GTM900C module as interface between internal network and external network, passed data and forwarded control commands. Terminal PC used LabVIEW graphical programming language, it could receive GPRS signal coming from Internet according to the fixed IP address and port number, and sent monitoring commands to the fixed IP address. This paper listed out hardware block diagram and software implementation process. The design concept can spread to other intelligent households. The experimental results suggest that the intelligent windows have implemented smart windproof, rainproof, anti-theft, fire prevention and prevent gas poisoning. It provided a good solution for the design of smart home.

The Phase Transition of W-Doped VO<SUB>2</SUB> Nanoparticles Synthesized by an Improved Thermolysis Method

High-quality thermochromic monoclinic VO2(M) and series of W-doped V(1-x)W(x)O2(M) nanoparticles were successfully synthesized by an improved thermolysis method. The products were investigated using X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) technologies. The measurement of DSC revealed that the metal-insulator phase transition (MIT) of 2.0% W-doped VO2 sample occurred at 25.6 degrees C, which was much lower than the MIT of host VO2(M) nanoparticles at 67.6 degrees C. The results showed that the proportion of the transmittance of tetragonal phase reached only about 29% of that of monoclinic phase for 0.5% W-doped VO2 at the wavenumber 900 cm(-1), which indicated W-doped VO2(M) was an intelligent window and optical switch materials.

Fast Switching Electrochromic Devices Containing Optimized BEMA/PEGMA Gel Polymer Electrolytes

An optimized thermoset gel polymer electrolyte based on Bisphenol A ethoxylate dimethacrylate and Poly(ethylene glycol) methyl ether methacrylate (BEMA/PEGMA) was prepared by facile photo-induced free radical polymerisation technique and tested for the first time in electrochromic devices (ECD) combining WO3sputtered on ITO as cathodes and V2O5electrodeposited on ITO as anodes. The behaviour of the prepared ECD was investigated electrochemically and electro-optically. The ECD transmission spectrum was monitored in the visible and near-infrared region by varying applied potential. A switching time of ca. 2 s for Li+insertion (coloring) and of ca. 1 s for Li+de-insertion (bleaching) were found. UV-VIS spectroelectrochemical measurements evidenced a considerable contrast between bleached and colored state along with a good stability over repeated cycles. The reported electrochromic devices showed a considerable enhancement of switching time with respect to the previously reported polymeric ECD indicating that they are good candidates for the implementation of intelligent windows and smart displays.

Solid electrolytes for electrochromic devices based on reversible metal electrodeposition

Air conditioning and lighting costs can be reduced substantially by changing the optical properties of “intelligent windows.” The electrochromic devices studied to date have used copper as an additive. Copper, used here as an electrochromic material, was dissolved in an aqueous animal protein-derived gel electrolyte. This combination constitutes the electrochromic system for reversible electrodeposition. Cyclic voltammetry, chronoamperometric and chromogenic analyses indicated that were obtained good conditions of transparency (initial transmittance of 70%), optical reversibility, small potential window (2.1V), variation of transmittance in visible light (63.6%) and near infrared (20%) spectral regions. Permanence in the darkened state was achieved by maintaining a lower pulse potential (−0.16V) than the deposition potential (−1.0V). Increasing the number of deposition and dissolution cycles favored the transmittance and photoelectrochemical reversibility of the device. The conductivity of the electrolyte (10−3S/cm) at several concentrations of CuCl2 was determined by electrochemical impedance spectroscopy. A thermogravimetric analysis confirmed the good thermal stability of the electrolyte, since the mass loss detected up to 100°C corresponded to water evaporation and decomposition of the gel started only at 200°C. Micrographic and small angle X-ray scattering analyses indicated the formation of a persistent deposit of copper particles on the ITO.

Road Traffic Monitoring by intelligence-driven window based image analysis

The term Traffic Analysis is the process to identify the different aspects of traffic and resolve the problems in concerning areas. These traffic problems may belong to traffic congestion and in order to remove this traffic congestion, determination of Road Traffic Volume or Road Traffic Identification is expected. There are several techniques [6], [9], [11] of determining traffic volume on a specific road or highway such as Road Traffic Volume Detection by using LASER Sensors [11], Road Traffic Volume Detection by using inbuilt electromagnetic loops installed in roads and Road Traffic Volume Detection by using concepts of Digital Image Processing [3], [4], [5]. Now these techniques have their pro and cons. But by far the best technique, from the point of view of Expense and Results, is Digital Image Processing. The goal of this paper is to analyze the density of road traffic by using the techniques and methods of Digital Image Processing and we are achieving this goal by using an intelligent window based system which has the capability to enhance its power according to the need of the system.