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Background: There is a hidden relationship between the degree of coronary artery stenosis and downstream myocardial remodeling. The mutual influence in myocardial ischemia and myocardial remodeling provides an index for quantifying the myocardial blood flow based on the principles of physics. Objectives: This study aimed to evaluate the advantages of myocardial blood flow index (MBFI) in the diagnosis of chronic obstructive coronary artery disease (CAD). Patients and Methods: The data of 68 patients (39 males; mean age: 57.0 ± 10.20 years) with suspected CAD were analyzed retrospectively, including the imaging findings of coronary computed tomography angiography (CCTA) and invasive coronary angiography (ICA) within one week. The MBFI was also calculated for the patients. After determining the optimal cut-off value based on ICA (stenosis ≥ 70%) as the gold standard test, the diagnostic performance of MBFI and CCTA was compared. The diagnostic accuracy was examined by the receiver operating characteristic (ROC) curve. For statistical analysis, chi-square test was performed to analyze influence data, and a P-value less than 0.05 was considered statistically significant. Results: In 68 cases evaluated in this study, the average scan dose of CCTA was 3.02 ± 1.15 millisievert (mSv). There were 28 cases with stenosis ≥ 70%. The optimal cutoff value of MBFI and CCTA was 0.111 and 70%, respectively. Also, the area under the curve (AUC) for MBFI and CCTA was 0.857 and 0.621 (Z = 2.091, P = 0.0365), respectively. The sensitivity, specificity, positive predictive value, and negative predictive value were 92.31%, 92.86%, 88.89%, and 95.12% for MBFI and 61.54%, 78.57%, 64.00%, and 76.74% for CCTA, respectively. The diagnostic accuracy was also estimated at 92.65% for MBFI and 72.06% for CCTA (χ2 = 9.844, P = 0.0017). Conclusion: In this study, MBFI performed better than CCTA in identifying lesions with stenosis ≥ 70%. A lower MBFI indicated the need for an upcoming active intervention, while a higher MBFI suggested avoiding unnecessary invasive testing.

Utilizing the Stimulus-Organism-Response paradigm, this study explores how self-disclosure, an important component of tourist-to-tourist interaction, influences tourist experience. Data were collected through a field experiment and analyzed via PLS analysis and PROCESS. Findings indicate that self-disclosure indirectly increases engagement by strengthening perceived cohesion and perceived intimacy. Perceived cohesion and perceived intimacy have indirect effects on satisfaction with experience, through engagement. Further, the initial tie strength moderates the effect of self-disclosure on perceived cohesion and perceived intimacy. These findings contribute to the development of tourism experience research from the perspective of tourist-to-tourist interaction and the social interaction literature by examining the unique interaction mechanism among tourists.

Background: In-stent restenosis (ISR) usually develops from stent neointimal hyperplasia (SNH), which will seriously weaken the effect of treatment. In this study, both SNH and ISR were classified as in-stent stenosis (ISS), and a non-invasive parameter – myocardial blood flow index (MBFI) was used to analyze its value in the diagnosis of stent abnormalities. Objectives: Analyzing the application of MBFI in the diagnosis of ISS. Patients and Methods: Clinical follow-up data for 572 patients with drug-eluting stent (DES) was collected continuously. Ninety cases were screened with the protocol of coronary computed tomography angiography (CCTA) and invasive coronary angiography (ICA) for the unrelieved symptoms. In-stent abnormalities included SNH (ISS < 50%) and ISR (ISS ≥ 50%). The ROC curve was analyzed using the optimal cutoff value of MBFI to evaluate the in-stent abnormalities. t-test of independent samples was used for the comparison data with normal distribution, and chi-square test was used for comparison of nominal variables. P < 0.05 was considered statistically significant. Results: Frequency of ISS was not statistically different between genders (χ2 = 0.105) (P = 0.7463). The optimal cutoff value was 0.082 with the area under the curve (AUC) of 0.829 (P < 0.001). The sensitivity, specificity, positive predictive value, and negative predictive value were 91.4%, 89.1%, 84.2%, and 94.2%, respectively, and the accuracy was 90.0%. Among 39 cases with MBFI ≤ 0.082, 34 (37.8%, 34/90) were with ISS, including 18 (20%, 18/90) of SNH, and 16 (17.8%, 16/90) of ISR. In the 39 cases with MBFI ≤ 0.082, there were eight (20.5%, 8/39) presented new lesions, and seven (17.9%, 7/39) presented severe lesions. Conclusion: MBFI could be used for evaluating ISS, and more attention should be paid to the new accompanying lesions for the high risk of severe lesions.

This study examines the influence of message framing and how a match or mismatch between message framing and individuals’ regulatory focus can influence their destination image perceptions and visit intentions utilizing attribute framing and regulatory focus fit theories. This study also examines the mediating role of cognitive fluency and emotional state on attribute framing effects on destination image formation and visit intentions. Findings indicate that framing of marketing messages exerts significant influences on consumers' decision making and destination selection process. Consumers under gain-framed message condition tend to have higher destination image perceptions compared to those under loss-framed message conditions. A match between attribute framing and regulatory focus results in formation of better destination image perceptions compared to mismatch. Furthermore, cognitive fluency and emotional state mediate attribute framing effects on destination image formation.

The evolution of crystalline structures under complicated dynamic conditions remains elusive in practical processing techniques including multi-melt multi-injection molding (M3IM), due to the obstacles in expressing the coupled external fields. Herein, we exploited the finite volume method (FVM) and the volume of fluid (VOF) method to uncover the coupled external fields of multi-melt flows in M3IM. The simulation results show that the shear rate curve changes significantly as the injection temperature of the second melt increases, while the shear fields and the shear heat significantly enhance as the injection speed of the second melt increases. Combined with the experimental observations, the relationship between the coupled external fields and the hierarchical crystalline structures is presented to elucidate the patterns and critical conditions for the formation of the diverse crystalline structures. This work paints a comprehensive picture of features governing the formation of hierarchical crystalline structures.

An adaptive neuro-fuzzy controller of nonlinear systems is presented based on data fusion method. It reduces the input dimension of the controller using data fusion technique and simplifies the fuzzy controller’s design. The fuzzy controller was designed with self-learning of neural networks. The simulation results show that the performance of the system is superior to that using conventional fuzzy controller. It is rewarding for the research on combination of data fusion method and intelligent control technique of nonlinear systems.

In this study, the hierarchical crystalline structures of high-density polyethylene (HDPE) samples molded by gas-assisted injection molding (GAIM) with different gas cooling times were characterized via scanning electron microscopy, two-dimensional wide-angle X-ray scattering, tensile testing techniques, and differential scanning calorimetry, respectively. It was found that the shish-kebab, the oriented lamellae, and common spherulite structures orderly distributed from the skin region to gas channel region of samples. More importantly, the wider area with highly oriented structure (shish-kebab) was obtained in the samples with longer gas cooling time, in that the longer gas cooling time tends to increase the cooling rate of polymer melt, and then much more stretched chains are retained. Although lower crystallinity, the higher degree of orientation, and much more shish-kebab structures lead to significant reinforcement from 28 to 785 MPa of the samples with gas cooling time of 0.5 s to 32 and 879 MPa of the samples with gas cooling time of 20 s for tensile strength and modulus, respectively. Finally, combined the HDPE molecular parameter with characteristic of the GAIM temperature field and flow field, the formation and stability of crystalline morphology in different regions of sample were discussed.

Electrolytic manganese industry production process generates serious environmental pollution and ecological problems. The wastewater treatment produced in the electrolytic manganese production has become a research hotspot in the fields of environment protection .In recent years, electrolytic manganese wastewater treatment focuses on various chemical processing methods and application of some technologies, there is little research on automation wastewater treatment equipment. In this paper, an automated processing system of electrolytic manganese wastewater is designed to meet the requirement of wastewater treatment and resource utilization, the equipment selects ion exchange method to dispose of wastewater manganese-containing and chromium-containing ion. The programmable logic controllers are used as the main controller, and configuration software is chosen as upper computer monitoring. The control system can efficiently implement ion exchange, regeneration, remote surveillance and other functions. This field operation shows that automated treatment equipment can automatically solve problem of electrolytic manganese wastewater treatment and resource utilization, and improve electrolytic manganese industry wastewater automation processing level．

Gas-assisted injection molding (GAIM) is an innovative plastic processing technology, which was developed from the conventional injection molding, and has currently found wide industrial applications. About 70% of the whole gas-assisted injection molding cycle is actually occupied by the cooling stage. The quality and production efficiency of molded parts are considerably affected by the cooling stage. Hence, it is necessary to study the solidification behaviors during the cooling stage. In this work, a simple experimental method was designed to simulate the solidification behaviors of high-density polyethylene during cooling stage of GAIM. The enthalpy transformation approach, coupled with the control-volume/finite difference techniques, was adopted to deal with the transient heat transfer problems with phase change effects. In situ measurements of the temperature decreases in the cavity were also carried out. Reasonable agreements between the experimental values and the simulated results such as cooling time, cooling rates, and temperature curves were obtained, which proved that this simple experimental method was effective. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Phase-change problems, also known as the “Stefan problems” or “moving-boundary problems,” are practically significant in modern technological and engineering fields. Injection molding, one of the m...

Gas-assisted injection molding (GAIM) is one of the significant fabricating technologies of plastics in modern industry, mainly owing to the light weight of products, good structural rigidity and dimensional stability, as well as shorter molding cycles. The objective of this article is to explore the temperature profiles during the cooling stage of gas-assisted injection molded high-density polyethylene (HDPE) parts using a transient heat transfer model of the enthalpy transformation method, which could always be utilized for the numerical studies of the phase-change heat transfer issues. The simulated results were validated by the in situ measurement of temperature decay, and good agreement has been observed. The comparison between GAIM and conventional injection molding (CIM) reveals that it is the rapid cooling rate (because of thin wall-thickness) and the inner gas cooling effects that together lead to the shortening of molding cycles. As cooling rate plays a part in the stabilization of the crystalline structure during the GAIM process according to our previous studies, this work is of significance for the operational designs in GAIM industrial applications and further investigation on the detailed mechanisms of various crystalline structures in GAIM parts. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers

The influence of melt and mold temperature on the solidification behavior of HDPE during the GAIM process is studied using a transient-heat-transfer model of the enthalpy transformation approach. An in situ measurement of temperature decay in the mold cavity was carried out to verify the simulated results experimentally, and reasonable agreement was observed. The comparison of the HDPE solidification behavior under various cooling conditions reveals that the rapid cooling rate (due to thin wall-thickness) is the main reason for the shortening of molding cycles, and that the mold temperature shows greater influence on the controlling of cooling rates than melt temperature during GAIM process.

Transient heat transfer problems with phase-changes, also known as the “Stefan problems” or “moving-boundary problems,” are practically significant in many engineering and technological fields. Injection molding, one of the most widely used plastics processing techniques, mainly consists of filling, packing, and cooling, and the cooling stage is crucial since it considerably affects the productivity and quality of the molded parts. Thus, solutions for transient phase-change heat conduction problems during injection molding will be instructive. In this article, the enthalpy transforming scheme proposed by Cao and Faghri, which could handle the Stefan problems for generalized multidimensional phase-change structures, is applied coupled with the control-volume/finite-difference techniques. Considering the polydispersity and hierarchical structures, the polymer extended phase change temperature range or mushy zone was included in the two-dimensional enthalpy formulation to forecast the transient phase-change heat conduction during the cooling stage for injection-molded high density polyethylene (HDPE) parts. Experiments were performed and good agreement has been achieved, which reveals that the enthalpy transforming model gives good prediction, especially for the cooling analysis for the injection molding of thick-walled parts of crystalline polymers. The understanding of the phase-change heat conduction characteristics may facilitate the optimal designs of polymer injection molding process for industrial applications. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers

Immiscible blends of poly(ethylene terephthalate) (PET)/polyethylene (PE) and polycarbonate (PC)/PE were examined to study the influence of the high interfacial contact (pseudo-adhesion) on the mechanical properties and the morphology developed during elongation. The high interfacial contact resulted from the contraction difference of the two polymers during cooling from the processing temperature to room temperature. As a result of the pseudo-adhesion, the tensile strength and modulus of the PET/PE and PC/PE blends increased steadily with the increase of PET and PC concentration. In PC/PE blends, numerous PC microfibers were formed in-situ, while in PET/PE blends, slippage took place between the PET particles and the matrix. Moreover, the macroscopic morphology development of both blends upon elongation was quite different. For PET/PE blend, necking was initiated at one point close to the non-gate end of the specimen, and then propagated uniformly from this point. For the PC/PE blend, necking-initating sites and propagation were irregular, and consequently the whole tested zone was deformed. The recoil of partially elongated specimens indicated that the recoverability of the PC/PE blend is higher than that of the PET/PE blend. Polym. Eng. Sci. 44:1561–1570, 2004. © 2004 Society of Plastics Engineers.

In the current work, the effect of ultra-high molecular weight polyethylene (UHMWPE) and temperature field on the unique double skin-core orientated structure and mechanical properties of high-density polyethylene (HDPE) parts molded by multi-melt multi-injection molding (MMMIM) were investigated using a variety of characterization techniques including rheological experiments, scanning electron microscopy (SEM), synchrotron small-angle X-ray scattering (SAXS), differential scanning calorimetry (DSC) and tensile testing. The SEM results revealed that a distinct double skin-core orientated structure was formed in samples molded via MMMIM. That is, compact lamellar together with typical shish-kebab structures was formed from the skin to the sub-skin, and large area of oriented lamellar was formed again near the core layer due to the significantly improved relaxation time of the UHMWPE/HDPE blend and intensive shear flow resulted from the secondary melt penetration process. Additionally, with increase temperature of the second melt, the oriented lamellar near the core layer tended to develop into irregularly-arranged lamellar and the double skin-core orientated structure weakened gradually. These results were further authenticated by SAXS. Results of tensile testing indicated that with reduced temperature of second melt, samples with higher tensile strength and modulus were obtained.

In this study, an increase in the cooling rate of high-density polyethylene parts was carried out via a change in the fluid flow pattern to introduce gas cooling under a gas-assisted injection-molding process; this was conducive to the retention of orientation chains shaped during the injection stage and further developed into much more oriented crystals. Morphological observation showed that the parts without gas cooling (WOGC) were composed of oriented crystals except the gas channel zone, whereas the parts with gas cooling (WGC) were full of oriented crystals, especially much more interlocking shish-kebab structures in the subskin zone. The WGC parts had a higher degree of orientation than the corresponding zone of the WOGC parts. Although the lower crystallinity, the wider orientation regions, and much more interlocking shish-kebab structures led to considerable increases from 32 and 990 MPa in the WOGC parts to 36 and 1150 MPa in the WGC parts for the yield strength and elastic modulus, respectively. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40349.

Information fusion is a key technique in modern air battle. A new information fusion algorithm based on fuzzy optimum theory is proposed in this paper. Fuzzy optimum theory is widely used in pattern recognition, multitarget sorting, etc. Using this information fusion algorithm, we discuss its detail process in air battle. The result represents its effective, and it is superior to Bayes statistical method and Dempster-Shafer evidence reasoning method.