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1.
The important field of research on ship operation is related to the high efficiency of transportation, the convenience of maneuvering ships, and the safety of navigation. This paper proposes an ontology-based fuzzy support agent for ship steering control and desires to testify the validity of the proposal by applying the fuzzy control model to the steering control system based on linguistic instruction. The fuzzy support agent is presented to build the maneuvering models of steersman and the miniature model for steering control system. The proposed fuzzy agent contains three main mechanisms, including the interpretation mechanism of linguistic instruction, the self-regulation mechanism, and the task performance mechanism. Furthermore, the task performance mechanism includes the kinematics module and the performance ontology. The simulation results show that the proposed approach can work effectively for ship steering control.  相似文献   
2.
In this study, we present the first preparation and corrosion protection studies of a series of electroactive polyimide-TiO2 (EPTs) hybrid nanocomposite materials containing conjugated segments of electroactive amino-capped aniline trimer (ATs) and TiO2 nanoparticles of ∼10 nm in diameter. Redox behavior of as-prepared EPTs hybrid materials was identified by electrochemical cyclic voltammetry (CV) studies. Higher concentration of TiO2 component in as-prepare corresponding EPTs was found to reveal better corrosion protection effect on cold-rolled steel (CRS) electrode based on sequential electrochemical corrosion measurements in 5 wt.% NaCl electrolyte. Enhancement of corrosion protection of EPTs coatings on CRS electrode could be interpreted by following three possible reasons: (1) Electroactive polyimide (EPI) could act as a physical barrier coating. (2) The redox catalytic capabilities of ATs units existed in EPTs may induce the formation of passive metal oxide layers on CRS electrode. (3) The well-dispersed TiO2 nanoparticles in EPTs matrix could act as effective hinder to enhance the oxygen barrier property of EPTs.  相似文献   
3.
Colorless and organo-soluble polyimide (PI) films have been synthesized from an alicyclic dianhydride BCDA and aromatic diamine 3,4′-ODA in the cosolvent of DMAc and GBL via one-step process. The graphene oxide (GO) was mixed with the above PI in DMAc solution to fabricate the PI/GO nanocomposite films. With the addition of only 0.001 wt% of GO in PI matrix, the resultant nanocomposite (PI/GO-0.001) exhibits not only the enhanced resistance to moisture but also retains superior visible light transmission, enhanced mechanical strength, and excellent dimensional stability, simultaneously. The water-vapor-transmission-rate (WVTR) significantly reduced to 30 g mil m−2 day−1 for this nanocomposite compared to 181 g mil m−2 day−1 for pure PI. Notably, the PI/GO-0.001 nanocomposite also exhibits low coefficient of thermal expansion (CTE) of 41 ppm °C−1, which is benefited from the homogeneous distribution of ultrathin GO nanosheets in PI matrix.  相似文献   
4.
Decomposition kinetics in thermogravimetric analysis (TGA) and dynamic mechanical relaxation in dynamic mechanical analysis (DMA) are used to study the high temperature lifetime of the new type of polyimide/poly(silsesquioxane)-like (PI/PSSQ-like) hybrid films, which are designed to form three-dimensional structures with linear polyimide blocks and a crosslinked PSSQ-like structure. Both TGA and DMA analysis reveal that the PI/PSSQ-like hybrid films have a longer lifetime (are more reliable) with regard to their thermal and mechanical characteristics than that of pure PI. Even just 2 wt% of p-aminophenyltrimethoxysilane (APTS) in a PI/PSSQ-like hybrid film can significantly improve the service lifetime by as much as at least four times in a TGA decomposition kinetic study. The dynamical relaxation data are well fitted to the calculated WLF (Williams-Landel-Ferry) master curves. In a series of X-PIS (PI modified with APTS) hybrid films, decreasing the PI block chain length increases the decomposition activation energy, lifetime (in both TGA and DMA) and relaxation modulus. In a series of X-PIS-y-PTS [PI modified with APTS and phenyltrimethoxysilane (PTS)] films, the decomposition activation energy and lifetime (in TGA) increase with the PTS content. Interestingly, the dynamic mechanical relaxation modulus of 10000-PIS-100-PTS film is lower than that of the corresponding 10000-PIS film at frequency > 102 rad/sec, but higher at frequency < 102 rad/sec. The 10000-PIS-100-PTS has a lower relaxation time than the 10000-PIS at the modulus 5×108 Pa, but the relaxation time of the former becomes higher at 5×107 Pa.  相似文献   
5.
In this study, we synthesized a reactive modifier [DOPO-tris(azetidine-2,4-dione)], terminated with three azetidine-2,4-dione functional groups, from [(9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-yl)tris(4-aminophenyl)methane; DOPO-triamine] and [4-isocyanato-4′-(3,3-dimethyl-2,4-dioxo-acetidino)diphenylmethane; IDD]. We embedded this reactive modifier, which contains multiple hydrogen bond donor and acceptor units, into epoxy resins to promote intermolecular interactions and to tailor its flexibility through the formation of unique pseudo-crosslinked polymer networks. The resulted epoxy resins were found to exhibit glass transition temperature as high as 187 °C and excellent flame retardancy with limited oxygen index (LOI) values around 38. Meanwhile, the dynamic mechanical analysis (DMA) of epoxy systems increases from 0.67 to 2.13 GPa for storage modulus and 0.73–1.67 GPa for loss modulus at 100 °C. Incorporation of reactive modifier into epoxy networks with noncovalent interactions via thermosetting blend was demonstrated to be an effective way to enhance the thermal and physical properties simultaneously.  相似文献   
6.
Emodin (1,3,8-trihydroxy-6-methylanthraquinone), a major constituent of rhubarb, has a wide range of therapeutic applications. Previous studies have established that emodin induces apoptosis in the inner cell mass and trophectoderm of mouse blastocysts and leads to decreased embryonic development and viability, indicating a role as an injury risk factor for normal embryonic development. However, the mechanisms underlying its hazardous effects have yet to be characterized. In the current study, we further investigated the effects of emodin on oocyte maturation and subsequent pre- and post-implantation development, both in vitro and in vivo. Notably, emodin induced a significant reduction in the rates of oocyte maturation, fertilization, and in vitro embryonic development. Treatment of oocytes with emodin during in vitro maturation (IVM) led to increased resorption of postimplantation embryos and decreased fetal weight. Experiments using an in vivo mouse model disclosed that consumption of drinking water containing 20–40 μM emodin led to decreased oocyte maturation and in vitro fertilization, as well as early embryonic developmental injury. Notably, pretreatment with a caspase-3-specific inhibitor effectively prevented emodin-triggered injury effects, suggesting that impairment of embryo development occurs via a caspase-dependent apoptotic process.  相似文献   
7.
This paper presents an approach for personal identification using hand geometrical features, in which the infrared illumination device is employed to improve the usability of this hand recognition system. In the proposed system, prospective users can place their hand freely in front of the camera without any pegs or templates. Moreover, the proposed system can be widely used under dark environment and complex background scenarios. To achieve better detection accuracy, in total 13 important points are detected from a palm image, and 34 features calculated from these points are used to further recognition. Experimental results demonstrate that the averaged Correct Identification Rate (CIR) is 96.23% and averaged False Accept Rate (FAR) is 1.85%. These results prove that the proposed contact-free system can be considered as an effective identity verification system for practical applications.  相似文献   
8.
Antimalware application is one of the most important research issues in the area of cyber security threat. Nowadays, because hackers continuously develop novel techniques to intrude into computer systems for various reasons, many security researchers should analyze and track new malicious program to protect sensitive and valuable information in the organization. In this paper, we propose a novel soft-computing mechanism based on the ontology model for malware behavioral analysis: Malware Analysis Network in Taiwan (MAN in Taiwan, MiT). The core techniques of MiT contain two parts listed as follows: (1) collect the logs of network connection, registry, and memory from the operation system on the physical-virtual hybrid analysis environment to get and extract more unknown malicious behavior information. The important information is then extracted to construct the ontology model by using the Web Ontology Language and Fuzzy Markup Language. Additionally, MiT is also able to automatically provide and share samples and reports via the cloud storage mechanism; (2) apply the techniques of Interval Type-2 Fuzzy Set to construct the malware analysis domain knowledge, namely the Interval Type-2 Fuzzy Malware Ontology (IT2FMO), for malware behavior analysis. Simulation results show that the proposed approach can effectively execute the malware behavior analysis, and the constructed system has also released under GNU General Public License version 3. In the future, the system is expected to largely collect and analyze malware samples for providing industries or universities to do related applications via the established IT2FMO.  相似文献   
9.
Nano- and submicron-sized vesicles are beneficial for the controlled delivery of drugs. Resveratrol, the main active polyphenol in red wine, was incorporated into various combinations of emulsions and liposomes to examine its physicochemical characteristics and cardiovascular protection. The blends of emulsion-liposome were composed of coconut oil, soybean lecithin, glycerol formal, and non-ionic surfactants. Multiple systems were assessed by evaluating the droplet size, surface charge, drug encapsulation, release rate, and stability. The vesicle diameter of the systems ranged from 114 to 195 nm. The liposomal vesicles in the systems had smaller diameters (of 43 approximately 56 nm) (F6 and F7). Drug encapsulation of approximately 70% were achieved by the vesicles. The inclusion of resveratrol in these systems retarded the drug release in both the presence and absence of plasma in vitro. The emulsion-liposome blends which incorporated Brij 98 (F5) exhibited the slowest release at zero-order for resveratrol delivery. Treatment using resveratrol in the blended formulations dramatically inhibited vascular intimal thickening, which was tested in an experimental model in which endothelial injury was produced in normal rat carotid arteries. Intraperitoneal injection of the multiple systems was associated with no or negligible liver and kidney toxicity. We concluded that encapsulation by the emulsion-liposome blends is a potent way to enhance the preventative and therapeutic benefits of resveratrol.  相似文献   
10.
In this study, electrochemical investigations of corrosion protection and the electrochromic properties of an aniline-pentamer-based electroactive polyimide (AP-based EPI) coating prepared by oxidative coupling polymerization are presented. The in situ chemical oxidation of the reduced form of soluble, electroactive poly(amic acid) (EPAA) in N-methyl-2-pyrrolidone (NMP) was monitored by UV–Vis absorption spectra. Moreover, the electroactivity of the AP-based EPI was evaluated by performing electrochemical CV studies. Based on a series of electrochemical measurements in 3.5 wt% NaCl electrolyte, the AP-based EPI coating was found to exhibit enhanced corrosion protection effects on cold-rolled steel (CRS) electrodes as compared to the corresponding non-electroactive (NEPI) coating. A possible mechanism for the enhanced corrosion protection of EPI coatings on the CRS electrode has been proposed as follows: (1) EPI coatings may act as a physical barrier and (2) the redox catalytic properties of the aniline pentamer units in EPI may induce the formation of a passive metal oxide layer on the CRS electrode, as evidenced by SEM and ESCA studies. The electrochromic performance of EPI was investigated by measuring electrochromic photographs and UV absorption spectra.  相似文献   
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