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The main objective of this paper is to establish an output/input relationship model based on machine learning for the fabric drying process of a general textile factory. The scenario of the fabric drying process involves a conveyor belt that drives the fabric through eight drying boxes, and the targeted metric of the post-drying fabric is the moisture content rate. This paper is composed of two main parts. The first part is to explain that how to select a predictive model measuring the output performance of the setting machine. The second part discusses the optimization of energy-saving parameters of multiple models chosen in the first part. This paper will introduce some techniques such as neural networks and machine learning algorithms to find the most suitable output/input relationship model, or so called “drying process quality prediction model”, for future development of energy saving.

Based on the top-seed infiltration and growth (TSIG) technique, two Y–Ba–Cu–O (YBCO) single-grain samples were successfully grown with two different kinds of liquid sources: Y 2 O 3 +10BaO+16CuO and Yb 2 O 3 +10BaO+16CuO, labeled as Y-LS and Yb-LS respectively, and systematical comparisons of their microstructure and superconducting properties were carried out. Microstructural observations indicate that the Yb-LS sample exhibits both the micro-sized Y 2 BaCuO 5 (Y-211) particles and the nano-sized Y-211 inclusions with smaller sizes than the Y-LS sample, and the energy dispersive spectrometry (EDS) result confirms the existence of Yb element with a concentration up to 0.46 wt% in Yb-LS processed sample. Measurements of superconducting properties showed that, a slightly higher levitation force (29.09 N) and a slightly reduced T c (90.3 K) were observed in the Yb-LS sample, compared with the result (28.54 N and 90.8 K) in Y-LS sample. While for J c property, both a higher zero-field J c of 8.41×10 4 A/cm 2 and an obvious peak effect of 4.33×10 4 A/cm 2 at a higher field of 1.4 T were observed in the Yb-LS sample, indicating the existence of stronger δl -type pinning from smaller Y-211 particles/inclusions, as well as stronger δT c -type pinning from the spatial fluctuations in matrix composition. The results prove the positive impact of the diffused Yb element on YBCO bulk superconductor and validate the element diffusion-doping route through the liquid infiltration.

Multi-grain Mg-doped Nd–Ba–Cu–O (Mg-NdBCO) bulk was facilely prepared by employing just one precursor pellet of composition Nd 1.6 Ba 2.3 Cu 3.3 O x + 1 wt% MgO. The sample exhibits typical large grains up to 15 mm in dimension, and a series of large Mg-NdBCO crystals of size 5 × 5 mm 2 can be cleaved from the multi-grain sample. Single-grain Y–Ba–Cu–O (YBCO) superconductor of 16 mm in diameter has been successfully grown on the seeding of the Mg-NdBCO large crystal by the infiltration growth (IG) technique, which presents superior performances of levitation force (32.17 N) and trapped field (0.3962 T) compared with the sample grown with a small seed. As a result, by combining the large Mg-NdBCO seed with the novel IG technique we proposed, a practical method for fabricating high-performance YBCO bulk superconductors has been developed.

Nano-composited Y–Ba–Cu–O (YBCO) single-grain superconductor has been facilely fabricated using raw metallic oxides. In this new method, a solid source pellet (SSP) of composition nano-Y2O3 + BaO + CuO + 1wt.%CeO2 and a liquid source pellet (LSP) of composition Yb2O3 + 10BaO + 16CuO are employed. Because the step of precursor powder synthesis in the conventional technique can be omitted, so the whole process flow is much simplified and the experimental efficiency is advanced. Experimental results indicate that, the sample exhibits homogeneous distribution of nano-sized Y2BaCuO5 (Y-211) inclusions in microstructure, and also a Jc performance of 6.24 × 104 A/cm2 in self field at 77 K, which is about 22% higher than that observed in conventional infiltration processed sample. Consequently, this study supplies a practical method for fabricating nano-composited YBCO bulk superconductor with high performance.

Barium calcium titanate (Ba0.96Ca0.04)(Zr0.05Ti0.95)O3 ferroelectric ceramics were prepared by sol–gel technique. The ceramics were sintering at 1290°C-1370°C. X-ray diffraction was employed to investigate the microstructure, and the surface topography was investigated by SEM graphs. The dielectric constant vs temperature was measured by Temperature dielectric spectrometer, and TF Analyzer 2000 measured the ferroelectric properties. It can be found that all the ceramics show pure perovskite structure suggesting that solid solution were formed. SEM showed that the samples uniform in grain size at 1330 °C. Our study revealed that when the sintering temperature is 1330 °C the maximum dielectric constant was 29,600, the maximum piezoelectric coefficient d33 could reach 399pm/V and the remanent polarization (Pr) was 8.3 μc/cm2, respectively.

BaTiO3 nanotube arrays are prepared by hydrothermal reaction using the TiO2 nantotubes prepared by anodic oxidation reaction. The element, structure, elementary composition and ferroelectric properties are researched by SEM, XRD and TF Analyzer. The result shows that the prepared BaTiO3 arranged orderly and have tetragonal structure after annealing. The diffracted intensity increased with the hydrothermal temperature rising up. With the increasing of Ba(OH)2 concentration, remnant polarization intensity and coercive field climbed up and then decreased. With the increasing of hydrothermal temperature, remnant polarization intensity and coercive field increased. When the Ba(OH)2 concentration is 0.3mol/L, the hydrothermal temperature is 260°C,the remnant polarization and coercive field of the samples reached the maximum and respectively reached 6.69mC/cm2 and 1.32 kV/cm.

The average particle size of SiC used as raw materials is 60 μm, the filter membrane in a mass ratio of each component are: SiC : binder: sodium carboxymethyl cellulose (CMC): deionized water =9:1:1:20. Method of producing membrane by means of spin coating, the sintering temperature was set in different ranges. The Archimedes drainage method was used to measure its porosity, and the filter pressure of membrane was charactered by the filter pressure testing system, SEM was performed to characterize its surface morphology and microstructure. The results show that: when the temperature rises from 1225 °C to 1325 °C, the filter pressure of SiC porous ceramic filter membrane decrease firstly and then increase; the atlas trend of the porosity is roughly opposite with the filter pressure, the maximum of the porosity value is about 42% when the temperature reaches 1300°C, at this temperature, the filter pressure reaches a minimum value and the surface of the filtration membrane is the most flat. When the temperature reaches 1350 °C, the surface of the film started showing a plaque.

Spin coating method was adopted for preparation of two types of SiC filter membrane with different particles size. Sintering temperature was set at 1300°C. SEM was performed in order to characterize its micro-structure. For measuring the porosity of the membrane, we used Archimedes drainage method. The filter pressure testing system was used to character the membrane filter pressure drop. The experiment results indicated that, when the filter membrane was composed of average diameters 45μm and 23μm SiC particles, with their thickness reached about 300μm and 150μm respectively and the amount of ceramic binder was 10%, the porosity of the membrane achieved 43%, the surface of filtration membrane structure was uniform, and its filter pressure was smaller. On the premise of satisfying specific filtering accuracy and efficiency, larger size of silicon carbide particle could offer better performance of the membrane.

A coated infiltration growth technique was proposed to fabricate single-grain Y?Ba?Cu?O bulk superconductor, in which a liquid source coated Y2BaCuO5 (Y-211) preform was employed and the liquid source composition was 3BaO + 5CuO. Experimental results indicated that, the sample exhibited a single-grain morphology on the top surface, and the liquid source coating always existed surrounding the bulk which contributed to the complete growth of the sample. The homogeneous distribution of fine Y-211 inclusions in microstructure and a satisfactory Jc performance of 5.67 × 104 A/cm2 in self-field at 77 K have also been observed.

Top-seed infiltration and growth technique (TSIG) is proposed to fabricate Y–Ba–Cu–O (YBCO) single-grain superconductor nano-composites, in which a solid source composition of nano-Y2O3 + BaCuO2 and a liquid source composition of Y2O3 + 10BaO + 16CuO are employed. As can be seen, this novel technique uses just one source of precursor powder of BaCuO2, so it is more simplified and efficient. Microstructural observation indicates that fine Y2BaCuO5 (Y-211) inclusions with a size from dozens of nanometers to about one hundred nanometers are successfully introduced in YBa2Cu3O7−x (Y-123) superconducting matrix, which can act as more effective pinning centers for improving the bulk performance. Superconducting property measurement shows that, a maximum trapped field of 0.36044 T is present at the center of the sample after magnetization by a permanent magnet (B = 0.5 T). These results prove that our proposed TSIG technique is a practical method for fabricating YBCO bulk superconductor nano-composites with high performance.

Lead-free (Ba0.97Ca0.03) (Zr0.18Ti0.82) O3(BCZT) ceramic is prepared by sol-gel technique. The sample shows a pure perovskite structure through the XRD pattern. Well-developed grain morphology and a dense microstructure are acquired at an optimistic sintering temperature (~1330°C). The BCZT ceramic shows a surprisingly high piezoelectric coefficient of d33=675 pm/V. The switching current curves are acquired in the different external fields by TF-2000 Ferroelectric Analyzer. It is found that with increasing the temperature, there is a decrease in the coercive field (Ec), and with increasing the electric field, there is an increase in the switching current obviously. Sintering temperature has an effect on switching current. The effect of temperature and electrical field on switching current is analyzed from viewpoint of the energy.

Ceramic fibers and whiskers have been used for modification of toughness because they increase fracture energy due to their high elastic modulus strength. The mechanism of this increase is well known to be pull-out, crack deflection and a bridging mechanism. This study focused on the increase in toughness, strength and thermal shock resistance when using mullite fibers in a gas filter for high temperatures. The green body uses the average 230μm particle diameter of SiC powders, which used as a skeletal material , the length to diameter ratio greater than 10 of the mullite fibers and the mixture of kaolin, feldspar and silica, which was used as a binder. The pore former be made up of graphite and active carbon. The molding pressure is 3MPa, and sintering temperature is 1300°C. The mullite fiber reinforced SiC porous ceramic has low filter pressure drop, 30.36% porosity and 35.66MPa flexural strength, which is higher than the SiC porous ceramic whitout mullite fibers. And the flexural strength degradation was only 5.4% after thermal shock tests.

Barium titanate nanotubes arrays were synthetized by in-suit hydrothermal method using TiO2nanotubes as both template and reactant in titanium substrate. Highly ordered nanotubes arrays and the spacing between nanotubes are apparent. XRD indicates that the samples have excellent crystallization and perovskite structure. Typical ferroelectric hysteresis loop of as-formed barium titanate nanotubes arrays with remanent polarization and coercive field are 6.72 and 48.7kV/cm.

SiC/Al2O3 composite porous ceramics were prepared by an in situ reaction bonding technique and sintering in air with SiC and A1(OH)3 as starting materials. The pores in the ceramics were formed by stacking particles of SiC and A12O3. The surface of SiC was oxidized to SiO2 at high temperature. With further increasing the temperature, SiO2 reacted with A12O3 to form mullite. The reaction bonding characteristics, phase composition, and mechanical strength as well as microstructure of porous SiC ceramics were investigated.

The porous SiC-cordierite ceramics were prepared from SiC, calcined kaolin, talc, aluminum hydroxide, and graphite as pore-forming. The influence of pore-forming agent contents and sintering temperatures on the porosity and flexural strength of porous SiC-cordierite ceramics were investigated. The grain phases and the fracture surface micrograph were analyzed with XRD and SEM, respectively. The results show that the sample sintered at 1350°C for 3h with 15% graphite as the pore-forming agent exhibits the most excellent properties: flexural strength of 63.74MPa was achieved at a porosity of 31.80%.

The complex dielectric behaviors of ferroelectric barium titanate (BT) ceramics were investigated. The dielectric properties were studied as a function of temperature and frequency using broadband dielectric spectrometer. The results show that the maximum value of dielectric constant occurs at 500nm BT ceramics, which is approximately 7,500; the dielectric loss is lower than 0.03 with the temperature varying from 225 K to 450 K. Dielectric constant and dielectric loss experience three dielectric peaks corresponding to rhombohedral to orthorhombic, tetragonal and cubic transitions. With the frequency ranges from 1 MHz to 1 GHz, the dielectric relaxation is apparently present. The relaxation process obeys Cole-Cole relaxation model at high temperature and conforms to Debye relaxation model when the temperature far lower than Curie temperature. The relaxation time is the order magnitude of ~10-9s obtained by Havriliak-Negami function fitting, which is very consistent with theoretical calculation.

Silicon carbide ceramic composite filter membrane materials were prepared by dry pressure molding and synchronous sintering process at sintering temperature of 1300oC for 3h. and research the influence of on the molding pressure structure of SiC filtration membrane,effect of particle size on porosity, average pore size and filter pressure drop of filtration membrane, SEM was performed to examine the morphology, The porosity ,average pore size and filter pressure drop of filtration membrane were tested by Archimedes method ,bubble point method and filter pressure drop instrument. It is demonstrated that while the molding pressure (F) varied from 1MPa to 10MPa, the filter membrane material achieved preferable morphology and best performance when F equals to 5MPa. Under this modeling pressure, while silicon carbide particle size increased from 1 to 23μm, the pore ratio decreased from 48.0% to 36.2% and the average pore size increased from 0.35μm to 9.4μm, while the air gas velocity changed from 0 to 0.112m/s, the filter pressure drop increased, when the velocity is stable, the filter pressure drop reduced as the silicon carbide particle size.

A series of single-grain Y–Ba–Cu–O (YBCO) bulk superconductors were fabricated using a modified infiltration growth (IG) technique, and the morphology feature associated with the inner crystallization structure of the samples was investigated in detail. Experimental observations indicated that YBCO single grains grew much larger with the increasing slow-cooling time. A bended a/c growth sector boundary was observed in the cross section of the YBCO sample grown for 48 h, which resulted from the variations in the Ra/Rc ratio during the slow-cooling growth process, where Ra and Rc represent the growth rate in the a axis and c axis direction, respectively. In addition, different side surface morphology (SSM) patterns were presented for the samples fabricated with different processings, which originated from the difference in the crystallization structure of the YBCO single grains and could be divided into four groups. On the other hand, for a defined inner-crystallization structure, the changes of sample size...

Barium titanate (BaTiO3) ceramics with grain size varied from 1000 to 8 nm were prepared by two step sintering method (TSS) and spark plasma sintering (SPS), respectively. Mixture structures of BaTiO3 ceramics were proved by in-situ temperature high resolution x-ray diffraction. Multiple ferroelectric domains present in nano-crystalline BaTiO3 ceramics were observed by transmission electron microscope. The evolution of phase transitions supported the existence of intrinsic mechanism. Dielectric loss of fine grain size BaTiO3 was higher than coarse grain size during Curie phase transition due to diffuse phase transition and grain boundary effects.

Ba0.95Ca0.05)TiO3 (BCT) ferroelectric ceramics were prepared from powders synthesized using a sol–gel process. Structural evolution of the BCT dry gels are investigated by thermal gravimetric analysis differential scanning calorimetry. It is found that BCT crystallites can be formed before 800°C. Well-sintered samples are synthesized at 1320°C for 2h. The crystal structure of the BCT ceramics is studied by XRD and ferroelectric properties of the ceramics are characterized by TF analyzer 2000. The Curie temperature Tc of the BCT ceramics is at about 130°C. The maximum dielectric constant (εr) reaches about 13678 at 130°C and hysteresis loops are measured with the temperature range from 25°C to 150°C.

The different concentration La2O3-doped BaTiO3 ceramics were prepared by sol-gel method. The ferroelectric and dielectric properties of the ceramics are characterized by TF analyzer 2000. With the increased amount of La2O3-doped, the dielectric constant increase gradually, when the sintering temperature is 1250 °C, the dielectric constant has reached 4648 for La2O3 with 0.4％-doped. With the temperature increased the dielectric constant of La-BaTiO3 increase gradually, when the sintering temperature is 1290 °C, the dielectric constant has reached 7066 for La2O3 with 0.4％-doped.

BaZr0.25Ti0.75O3(BZT) ceramics were prepared by conventional ceramic process at a relatively low sintering temperature and with an addition of Li2O as the liquid-phase sintering aid. X-ray diffraction characterized results showed that the main crystal phase of the samples with 1.0wt% Li2O additive sintered at 1050°C～1250°C for 4h presented perovskite structure. The dielectric properties of BZT ceramics have been investigated. The dielectric constant of 1.0wt% Li2O doped BZT sintered at 1150°C decreased, and the dielectric loss increased by 0.0012 compared with that of the pure BZT sintered at 1450°C.

The dielectric characteristics of Barium titanate (BT) based ceramics are evaluated in a broad frequency range at room temperature and at elevated temperature; the measured frequency is 0.1Hz to 1GHz. The results showed that the dielectric constant increases sharply with the decreasing frequency and is higher than 3000 appeared in lower frequency for Mg 1% doped BT bulk ceramics, which may be resulted from space charge polarization becoming more dominant as compared to the dipolar polarization especially when the frequency is lower than 1 kHz. The dielectric relaxation peaks of Mg-doped BT bulk ceramics appeared both at low and radio frequency whereas pure BT ceramics showed relaxation peak only at radio frequency, what's more, the relaxation frequency of Mg-doped sample is rather low than pure barium titanate ceramics. The dielectric relaxation motion approximately obeys Debye relaxation model approved by Cole-Cole diagram. Thermal activation energy is 0.46eV obtained by Volgel-Fulcher law fitting, which demonstrated that dielectric relaxation due to oxygen vacancies in the Mg-doped BT ferroelectric ceramics.

(Ba0.7Ca0.3)TiO3 (BCT) powders and ceramics have been prepared by sol-gel technique. Structural evolution of the BCT dry gels are investigated by thermal gravimetric analysis–differential scanning calorimetry. It is found that BCT crystallites can be formed before 800 . Well-sintered samples are synthesized at 1260 for 2h. The crystal structure of the BCT powders is studied by XRD and ferroelectric properties of the ceramics are characterized by TF analyzer 2000. The Curie temperature Tc of the BCT ceramics is at about 125 . The maximum dielectric constant (εr) reaches about 4851 at 125 and hysteresis loops are measured with the temperature range from 25 to 150 .

Barium zirconate titanate Ba(Ti1-yZry)O3 (BZT, y = 0.02, 0.07, 0.09, 0.12, 0.15) ceramics have been prepared by sol–gel process. All the BZTx ceramics exhibited perovskite phase detected by X-ray diffraction, and the diffraction peaks shift to lower angle with increasing the content of Zr. Dielectric susceptibilities are up to 15500, and tunability up to 74.9% under electric field 6.8 kV/cm at 100 Hz.

Hysteresis loop and dielectric properties of lead-free BaTiO3-La2O3 piezoelectric ceramics and BaTiO3 ceramic compared with pure BaTiO3 has been systematically studied. The amount of La2O3 addition ranged from 0.3~0.5mol% by controlling the sintering temperature. Dielectric properties of BaTiO3-La2O3 were promoted after the addition of La2O3, the maximum value of dielectric constant reached 8,624, recently. The role of La2O3 on the solid-state sintering of BaTiO3 is discussed on the basis of the solid-solution defect model.

The(1-x)BaTi0.8Zr0.2O3-xBa0.7Ca0.3TiO3 ceramics have been prepared by sol-gel technique, where x is from 0.2 to 0.6. It reveals that the dense ceramics can be obtained when the sintered temperature is above 1250°C. It is lower than that of solid state reaction ceramics. In particular, when x=0.3, at which is near the MPB composition, the ferroelectric and piezoelectric properties are more excellent than the others. The maximum dielectric constant is above 9000, which can be observed in the butterfly shape curves of dielectric constant as a function of electric field. The maximum piezoelectric coefficient d33 can reach 400 pm/V, and it is obtained from the piezoelectric response loops.

Highly-ordered titania nanotube arrays were fabricated in ethylene glycol polar organic electrolyte containing a certain amount of sodium fluoride. Series of patterned nanotube arrays with different outside diameter and aspect ratio were obtained via optimizing anodic voltage, the concentration of fluoride ion and reaction time. The as-prepared nanotube arrays were amorphous and transformed single anatase phase characterized by X-ray diffraction with annealing under the condition of 450oC for 3h. Cyclic voltammogram behaviors were discussed using electrochemical workstation. The pH value of electrolyte, the scanning rate, the crystal structure and morphology of the samples have a significant effect on the reductive/oxidative and H+ intercalation properties.

The (Ba0.88Ca0.12)( Zr0.12Ti0.88)O3 powders and piezoelectric ceramics were prepared by sol-gel process. The reaction process was analyzed with the help of thermo gravimetric and differential scanning calorimetry. X-ray diffraction characterized results showed that the structure of the (Ba0.88Ca0.12)( Zr0.12Ti0.88)O3 powders was perovskite structure and the particle size was approximately 37nm. Piezoelectric measurements revealed that Curie temperature and the maximum piezoelectric coefficient d33 is 95°C and 215pm/V, respectively.

Bulk dense nanocrystalline BaTiO3 ceramics ranging from 15 nm to 100 nm have been successfully prepared by the spark plasma sintering method. Raman spectra and X-ray diffraction were used in combination with electron microscopy to study the evolution of lattice structure and phase transformation behavior with grain growth from nanoscale to micrometre scale for BaTiO3 ceramics. Scanning nonlinear dielectric microscopy measurements revealed temperature-dependent variations in contrast, which were attributed to domain rearrangements in BaTiO3 ceramics below 100 nm. Furthermore the piezoresponse hysteresis loops showed that the nanocrystalline BaTiO3 ceramics were switchable and ferroelectricity was retained at the high temperature of 290 oC, demonstrating the existence of nano ferroelectric domains and the ferroelectric phase still retained above Curie temperature, which confirmed the diffused phase transition character in nanograin BaTiO3 ceramics. The dielectric data also show a ferroelectric to paraelectric phase transition in nanograin BaTiO3 ceramics.

The full potential linearized augmented plane wave method within the generalized gradient approximation was used to calculate electronic structure of nanocrystalline BaTiO3 ceramics. We calculated the total and partial density of states of 50 nm BaTiO3 ceramics. The results show that the atoms distribution of nanograin BaTiO3 ceramics is different from those of coarse BaTiO3 ceramics. It is also revealed that the hybridization between Ti 3d and O 2p is very strong, which is very important to the ferroelectric stability of nanocrystalline BaTiO3 ceramics.

SrBi2Nb2O9 (SBN) with different Bi2O3 contents were prepared by solid-state reaction method and then spark plasma sintering. The Influence of Bi2O3 on the properties of SBN was studied. The results showed that the increased Bi2O3 contents can enhance densification and improve the dielectric properties. This might have close relation to the low melting point of Bi2O3 and special sintering way of SPS, which usually results in some change in micro-structure.

By employing the infiltration growth (IG) technique, Mg-doped Nd–Ba–Cu–O (NdBCO) seed crystals were successfully prepared through 1 wt% MgO addition both to a Nd4Ba2Cu2O10 (Nd-422) precursor powder and to a liquid source with the composition Nd2O3:CuO:BaCuO2 = 1:6:10. Differential thermal analysis (DTA) results showed that the decomposition temperature of the processed Mg-doped NdBCO crystals increased by about 20 °C compared with the general, Mg-free NdBCO seeds, thus they can be used as generic seed crystals to induce the growth of any RE–Ba–Cu–O (REBCO) single grain. This result is consistent with that observed in melt growth (MG) processed Mg-doped NdBCO crystals. Finally, highly c-axis oriented Gd–Ba–Cu–O (GdBCO) and Y–Ba–Cu–O (YBCO) large grains were successfully grown using the produced seed crystals.

There has been great progress in the last decade in the synthesis of nanopowders with highly controlled size and size distribution. Meanwhile, the development of an unconventional pressureless two-step sintering strategy enabling densification without grain growth provides a novel technology suitable for commercial production of nanograin ceramics. The particular interest concerning bulk dense nanograin ceramics is the manifestation of ferroelectricity, which remains a fundamental issue to be understood and exploited. Combining the best powder synthesis and optimized two-step sintering, high-density barium titanate (BT) and related nanograin ceramics have been fabricated to allow for a detailed determination of the size effect on nanometer-scale ferroelectricity and piezoelectricity of fundamental and industrial interest. These include dense ceramics of undoped BT with an average grain size down to 5 nm, and of (1−x)BiScO3−xPbTiO3 (BSPT) solid solutions with an average grain size down to 10 nm. Here we review the fabrication methods of high-density BT and BSPT nanoceramics and the major findings of the size effect on their microstructure, phase transition and electrical properties. Robust ferroelectricity is demonstrated for the first time in 5 nm BT nanoceramics, while strong local piezoelectricity is present in 10 nm BSPT nanoceramics.