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Two novel bipolar host materials based on carbazole and triarylborane moieties, i.e. B-2CZ and m-B-CZ, are synthesized and characterized. The spatially crowded compound B-2CZ exhibits a high thermal stability (Td > 340 °C) compared to the reported triarylboryl carbazoles, presumably due to the highly compact architecture. As a result, phosphorescent Ir(ppy)3 combined with both the borylated compounds is selected to construct a host-guest system. Devices A (B-2CZ) and B (m-B-CZ) achieve peak efficiencies of 19.3% (69.1 cd/A and 88.1 lm/W) and 19.1% (66.1 cd/A and 77.2 lm/W), respectively. The respective turn-on voltages of devices A and B are recorded at 2.4 and 2.6 V, which are much lower than that of device with the benchmark host (mCP, 3.3 V). In addition, at a higher practical luminance of 100 cd/m2 (1000 cd/m2), the external quantum efficiencies of devices A and B are still preserved at 19.1% (17.3%) and 18.2% (13.0%) with the mitigated efficiency drops of 1% (10%) and 5% (32%), suggesting the promising advantage for realizing efficient phosphorescent organic light-emitting devices.

Coal ash slag viscosity is the most important parameter for the design and the stable running of entrained flow gasifier. Iron serves as the most abundant variable-valence element in coal ash slag, but the effects of iron in coal ash slag on viscosity and slag crystallization under the gasification conditions are not available. In this research, the iron transformation behaviors are discussed, and predictive models for iron transformation based on the ash chemical composition, atmosphere, slag residence time and temperature are established. In the fully liquid slag, Fe2+/Fe3+ increases with SiO2/Al2O3 (mass ratio) and temperature, but it decreases with the increasing iron content, α value (α = CaO/(SiO2+Al2O3), mass ratio), and oxygen partial pressure. The equilibrium and kinetic model considering CO and H2 diffusion is built for prediction of Fe2+/Fe3+ in slag at given temperature, oxygen partial pressure, and residence time. The model is applied to predict the Fe2+/Fe3+ of Yanzhou coal and it is found that Fe2+ in Shell slag is higher than that in Texaco slag. In partial crystalline slag, the iron transformation is sensitive to the variations of SiO2+Al2O3 and SiO2/Al2O3 because of the formations of melilite and spinel. The prediction models for melilite and spinel transformation are also built, but the result has not been validated due to lack of in-situ results in the commercial gasifier. The above models offer the guidance for the prediction and adjustment of slag behavior in the gasifier, especially for the iron-rich coal.

The ash fusibility, usually investigated and evaluated by the ash chemical composition, is widely used for guiding the coal utilization in boiler and gasifier. The ratio of basic and acidic oxides (B/A) in coal ash is the most important parameter for ash fusibility evaluation. While the coal ash has the identical B/A ratio, SiO2/Al2O3 and CaO/Fe2O3 ratio also show significant influence on the ash fusibility. However, the researches on CaO/Fe2O3 on ash fusibility are rare. In order to quantify the influence of CaO/Fe2O3 on the ash fusibility, thermal mechanical analyzer (TMA) is applied to investigate the ash fusion behavior of coal ash with various CaO/Fe2O3 ratios. XRD, FactSage and DSC are combined to explore the ash fusion characteristics and mechanisms. The results showed that AFTs increased with the increasing of CaO/Fe2O3 ratio, which was attributed to variation of Fe2O3 content and iron valence. However, the ash with low CaO/Fe2O3 ratio trended to form mullite, increasing AFTs. Hence, the optimal CaO/Fe2O3 ratio for fluxing effect existed to balance the mineral component and iron valence. The different shrinkage curves were attributed to the different fusion events and different mechanism. The fusion process of ash (CaO/Fe2O3 = 0.25) exhibited as the behavior of a pure substance, which has the narrow fusion range. And the fusion range was dominated by the low temperature eutectics including spinel, quartz, corundum, and anorthite, which were beneficial for preventing ash sintering. Meanwhile, the fusion process of ash sample (CaO/Fe2O3 = 4) occurred step by step, and it had a wide fusion range. The low-melting point minerals such as wollastonite, clinopyroxene, calcium silicate induced and manipulated the fusion process. These ash samples with the wide fusion range were favored for slagging process. Besides, the shrinkage rate of ash was mainly determined by the slag formation rate when viscosity was low, but it was dependent on slag formation rate as well as viscosity for the high viscosity slag. Two correlated relations between shrinkage rate and ratio of liquid phase formation rate and viscosity for ash with CaO/Fe2O3

TADF molecules with a higher horizontal–dipole ratio have recently been realized to show a large conversion efficiency in organic light-emitting diodes (OLEDs) and hence great promise for their application in display and solid state lighting sources. The current work focuses on fine-tuning the structure of the parent 2,6-diphenylpyrimidinyl compound PhPMAF and its derivatives with a series of 2,6-dipyridylpyrimidine acceptors; namely: 2NPMAF, 3NPMAF and 4NPMAF, among which the intramolecular CH⋯N bonding interaction was confirmed for 2NPMAF, showing good agreement with the NMR results. The solvatochromism and TADF behaviors, together with TD-DFT computations, of the titled compounds were explored to gain insights into the structure–photophysics relationship. Eventually, these functional 2,6-dipyridylpyrimidine acceptor based TADF compounds exhibit electroluminescence ranging from deep-blue to sky-blue, among which an external quantum efficiency (EQE) of 24.9% was achieved for the derivative 3NPMAF. The high horizontal–dipole ratios (∼0.86–0.91) obtained for this class of compounds elucidates the superior OLED performance. Moreover, the non-doped OLED architecture achieves an EQE of 14.1% for 3NPMAF, which is superior to that of PhPMAF with an EQE of 5.1%, demonstrating the significance of dipyridylpyrimidine as an acceptor for the future structural design of TADF emitters.

BACKGROUND The purpose of this study was to evaluate the utility of multi-detector computed tomography (MDCT) angiography and transthoracic echocardiography (TTE) in the diagnosis of congenital coarctation of the aorta (CoA) and accompanying malformations in infants. MATERIAL AND METHODS From January 2012 and December 2015, we enrolled 68 infants with clinically suspected CoA who underwent MDCT angiography and TTE in our hospital. Surgical correction was conducted to confirm the diagnostic accuracy of both examinations in all patients. RESULTS In this study, the diagnosis of CoA was confirmed infants by surgical results in 55 of 68 infants. The diagnostic accuracy, sensitivity, and specificity of MDCT angiography were 95.6%, 96.4%, and 92.3%, respectively. The diagnostic accuracy, sensitivity, and specificity of TTE were 88.2%, 90.9%, and 76.9%, respectively. There was no significant difference in diagnostic accuracy, sensitivity, and specificity between MDCT angiography and TTE (χ²=2.473, p>0.05, χ²=1.373, p>0.05 and χ²=1.182, p>0.05, respectively). In the diagnosis of concomitant cardiac abnormalities with CoA, the 2 methods also play different roles. CONCLUSIONS MDCT angiography and TTE play different roles in the diagnosis of CoA and accompany malformations. MDCT angiography in the diagnosis of the extra-cardiac vascular malformations is better than TTE, and TTE is superior to MDCT angiography in diagnosing intracardiac malformation. Combined MDCT angiography and TTE is a relatively valuable, reliable, and noninvasive method in the diagnosis of CoA and accompany malformations in infants.

This paper proposes the research and development of an Android-based mobile platform with a quadrotor control and quadrotor flight controller. The proposed Android-based mobile platform has the following advantages: (1) with Android remote controller has a bidirectional transmission function, which can transmit flight directives to the quadrotor and receive the feedback information to achieve the desired control. Additionally, the Android remote controller is designed on a mobile platform for convenient carrying. (2) The flight controller is designed with Proportional Integral Derivative (PID) Control and Sliding Mode Control methods to obtain optimum operations. Finally, parameters of optimum control are built and implemented by using Genetic and Tabu Search Algorithms. Experimental results are presented to verify the performance and the feasibility of the proposed Android-based mobile platform with a quadrotor control and quadrotor flight controller.

With the emergence of multi-view 3D videos, network operators now face a new challenge to resolve the dramatic increase of the network bandwidth required to support all subscribed views (typically 16 or 32) of a video. Recently, Depth-Image-Based Rendering (DIBR) in Computer Vision has been demonstrated as a promising way for efficient multi-view 3D video multicast, because many views can be synthesized in mobile devices and no longer need to be transmitted. Nevertheless, DIBR is computationally intensive and incurs additional power consumption in mobile devices, and unsubscribed views need to be transmitted to mobile users for DIBR. In this paper, therefore, we aim to leverage Mobile Edge Computing (MEC) for DIBR to foster effective and efficient multi-view video multicast. We formulate a new problem, named Multi-view Multicast Synthesis and Delivery (MMSD) and prove the NP-Hardness. We design an approximation algorithm, named Merge Search Forest Algorithm (MSFA), to choose the view to be synthesized and build a multicast topology including a low-cost forest for supporting each subscribed view. Simulation results manifest that MSFA outperforms the existing approaches by 30% to 50% of the total communication and computation cost.

Contamination of deoxynivalenol (DON) in grains is common worldwide and pigs are particularly susceptible to this mycotoxin. The distribution of DON in porcine tissues following intravenous administration was investigated in this study. Fifteen pigs were randomly divided into three groups. Animals in groups A and B were administrated with DON at the dose of 250 and 750 µg kg−1 body weight, respectively, while group C served as blank control. Plasma, bile and 27 tissues were collected at 30 min post-administration. DON concentrations in all samples were tested using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). To observe the distribution of DON in tissues, these samples were further subjected to the immunohistochemical analyses. Totally, the bile and 13 tissues were sampled for DON-based detection, including kidney, mesenteric lymph nodes, muscle, stomach, jejunum, colon, plasma, spleen, rectum, cecum, liver, ileum, and duodenum. No significant difference was observed for the concentrations of DON in duodenum, ileum and liver samples between groups A and B; while the DON concentrations in cecum and rectum of group B were significantly higher (P-value

In the paper, a near-infrared-ray (NIR) and side-view video based low-complexity drowsy driver detection system is developed for day and night applications. The proposed system detects drowsy conditions effectively whether or not glasses. To reduce the redundant computations, the pre-defined ROI (region of interest) is used at the procedures of face, glasses bridge, eyes, and nose feature detections. By the geometric based facial image processing, the eyes and nose positions are recognized, and the closed eyes and nod situations due to drowsiness are detected effectively. After simulating by self-made driver's video datasets, the average open/closed eyes detection accuracy rates without/with glasses are 95% and 84% in day, and are 89% and 87% in night, and the average drowsy detection accuracy is up to 90%. By software optimizations, the processing speed operates up to 150fps and 20fps in PC and the embedded system respectively for real-time drowsy driver detections.

The purpose of this study was to preoperatively evaluate the value of aortic arch lesions by multidetector computed tomography (MDCT) angiography in type A aortic dissection (AD). From January 2013 to December 2015, we enrolled 42 patients with type A AD who underwent MDCT angiography in our hospital. The institutional database of patients was retrospectively reviewed to identify MDCT angiography examinations for type A AD. Surgical corrections were conducted in all patients to confirm diagnostic accuracy. In this study, the diagnostic accuracy of MDCT angiography was 100% in all 42 patients. The intimal tear site locations that were identified in patients included the ascending aorta (n = 25), aortic arch (n = 12), and all other sites (n = 5). Compared with the control group, there were significant differences in the aortic arch anatomy among the cases. Regarding the distance between the left common carotid and left subclavian arteries, compared with the control group, most cases with type A AD had a significant variation. MDCT angiography plays an important role in detecting aortic arch lesions of type A AD, especially in determining the location of the intimal entry site and change of branch blood vessels. Surgeons can formulate an appropriate operating plan, according to the preoperative MDCT diagnosis information.

Cephalometric analysis is an essential clinical and research tool in orthodontics for the orthodontic analysis and treatment planning. This paper presents the evaluation of the methods submitted to the Automatic Cephalometric X-Ray Landmark Detection Challenge, held at the IEEE International Symposium on Biomedical Imaging 2014 with an on-site competition. The challenge was set to explore and compare automatic landmark detection methods in application to cephalometric X-ray images. Methods were evaluated on a common database including cephalograms of 300 patients aged six to 60 years, collected from the Dental Department, Tri-Service General Hospital, Taiwan, and manually marked anatomical landmarks as the ground truth data, generated by two experienced medical doctors. Quantitative evaluation was performed to compare the results of a representative selection of current methods submitted to the challenge. Experimental results show that three methods are able to achieve detection rates greater than 80% using the 4 mm precision range, but only one method achieves a detection rate greater than 70% using the 2 mm precision range, which is the acceptable precision range in clinical practice. The study provides insights into the performance of different landmark detection approaches under real-world conditions and highlights achievements and limitations of current image analysis techniques.

As information technology grows dramatically and the financial market of Taiwan turns out to be active, the investment management becomes very popular in recent years. To facilitate the rapid development of information technology and the financial market, the application of information to financial investment becomes an important issue as essential evaluation metrics. This paper focuses on modeling the business behavior of financial investment systems by the high-level fuzzy Petri net (HLFPN) for the purpose of developing an appropriate investment decision. Based on the HLFPN model, the proposed system provides individual investors to obtain relevant information to understand the investment trend. As a result, we propose a practical financial investment system to enhance investment benefits and to help investors achieve the desired goals to improve the economy.