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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Controlling Silicon Bottom Cell Lifetime Variance in II-VI/Si Tandems
摘要： This paper provides an overview of the main features of several bibliometric indicators which were proposed in the last few decades. Their pros and cons are highlighted and compared with the features of the well-known impact factor (IF) to show how alternative metrics are speci?cally designed to address the ?aws that the IF was shown to have, especially in the last few years. We also report the results of recent studies in the bibliometric literature showing how the scienti?c impact of journals as evaluated by bibliometrics is a very complicated matter and it is completely unrealistic to try to capture it by any single indicator, such as the IF or any other. As such, we conclude that the adoption of more metrics, with complementary features, to assess journal quality would be very bene?cial as it would both offer a more comprehensive and balanced view of each journal in the space of scholarly publications, as well as eliminate the pressure on individuals and their incentive to do metric manipulation which is an unintended result of the current (mis)use of the IF as the gold standard for publication quality.
关键词： impact factor,popularity indicators,prestige indicators,Eigenfactor,research evaluation,journal ranking,Bibliometrics
更新于2025-09-23 15:19:57
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Human Clinical and Histologic Evaluations of Laser-Assisted Periodontal Therapy with a 9.3-??m CO2 Laser System
摘要： This investigation was designed to evaluate the healing response of 9.3-μm CO2 laser–assisted periodontal therapy. Five patients presenting with moderate to severe periodontitis, with an initial pocket depth (PD) ≥ 5 mm and with teeth predetermined to be surgically extracted, were enrolled and consented to treatment with full-mouth CO2 laser–assisted therapy. The laser treatment was carried out in the Ultraguide Mode at a setting of 0.25-mm spot size, with an average power of 0.65 to 1.15 watts and 20% mist. The laser tip was passed from the gingival margin and down apically to the base of the pocket with a sweeping L motion. The teeth were intensely scaled with piezoultrasonic instrumentation afterwards. A second pass of the laser tip was performed for the study teeth. At 9 months, all patients were clinically reevaluated. For sites with an initial pocket depth of ≥ 7 mm, a mean PD reduction of 3.97 ± 1.36 mm and a mean clinical attachment level gain of 3.54 ± 1.54 mm were achieved, resulting in a mean PD of 3.91 ± 0.77 mm. En bloc biopsy samples of four teeth were obtained and analyzed; two demonstrated histologic evidence of new bone formation while the other two healed with a long junctional epithelium with minimal inflammatory infiltrate. Further long-term clinical studies are needed to investigate the treatment stability obtained with a 9.3-μm CO2 laser compared to conventional surgical therapy. Nevertheless, the encouraging clinical results indicated that adjunctive use of the 9.3-μm CO2 laser–assisted periodontal therapy can be beneficial for treatment of periodontally compromised patients.
关键词： histologic evaluation,periodontal therapy,periodontitis,laser-assisted therapy,CO2 laser
更新于2025-09-23 15:19:57
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Optimal configuration of hybrid-energy microgrid considering the correlation and randomness of the wind power and photovoltaic power
摘要： Despite rapid advances in the study of brain–computer interfaces (BCIs) in recent decades, two fundamental challenges, namely, improvement of target detection performance and multidimensional control, continue to be major barriers for further development and applications. In this paper, we review the recent progress in multimodal BCIs (also called hybrid BCIs), which may provide potential solutions for addressing these challenges. In particular, improved target detection can be achieved by developing multimodal BCIs that utilize multiple brain patterns, multimodal signals, or multisensory stimuli. Furthermore, multidimensional object control can be accomplished by generating multiple control signals from different brain patterns or signal modalities. Here, we highlight several representative multimodal BCI systems by analyzing their paradigm designs, detection/control methods, and experimental results. To demonstrate their practicality, we report several initial clinical applications of these multimodal BCI systems, including awareness evaluation/detection in patients with disorder of consciousness (DOC). As an evolving research area, the study of multimodal BCIs is increasingly requiring more synergetic efforts from multiple disciplines for the exploration of the underlying brain mechanisms, the design of new effective paradigms and means of neurofeedback, and the expansion of the clinical applications of these systems.
关键词： brain switch,multimodal brain–computer interface (BCI),awareness evaluation,Audiovisual BCI,cursor control
更新于2025-09-23 15:19:57
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Performance Evaluation and Optimization of a Building-Integrated Photovoltaic/Thermal Solar Water Heating System for Exterior Shading: A Case Study in South China
摘要： Building-integrated photovoltaic/thermal (BIPV/T) systems can produce both electrical and thermal energy through the use of photovoltaic/thermal modules integrated with building envelope. Exterior shading is a common way to improve summer indoor thermal environment of the buildings in low latitudes. This study presents a BIPV/T solar water heating system for exterior shading of residences. In order to evaluate and optimize the system performances, a model was developed to simulate the thermal and electrical production of such system. The simulations for an example system in Guangzhou, a city in South China, were performed to investigate the influences of tank installation height and panel tilt angle on system performances. According to simulation results, the suggested tank installation height is 0.6~0.8 m. The shading coefficient ranges from 0.797 to 0.828 when the tilt angle varies from 14° to 38°. The reduction of panel tilt angle causes a certain improvement of shading performance. The annual auxiliary heat reaches the minimum when the panel tilt angle equals 28°, and the annual electric energy output changes little when the panel tilt angle ranges from 20° to 28°. Comprehensively considering thermal, electrical, and shading performances, the suggested panel tilt angle is 20°~28°. The average thermal and electrical efficiencies are respectively 38.25% and 11.95% when the panel tilt angle ranges from 20° to 28°. The presented system is a promising way to provide hot water, electricity, and exterior shading for residences.
关键词： exterior shading,BIPV/T,thermosyphon photovoltaic/thermal water heater,performance evaluation and optimization
更新于2025-09-23 15:19:57
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[IEEE 2019 International Multi-Conference on Engineering, Computer and Information Sciences (SIBIRCON) - Novosibirsk, Russia (2019.10.21-2019.10.27)] 2019 International Multi-Conference on Engineering, Computer and Information Sciences (SIBIRCON) - The Use of Spread Spectrum Signals to Increase the Noise Immunity of Optical Communication Systems Based on the Effect of LED Reversibility
摘要： Data mining applications are becoming a more common tool in understanding and solving educational and administrative problems in higher education. In general, research in educational mining focuses on modeling student’s performance instead of instructors’ performance. One of the common tools to evaluate instructors’ performance is the course evaluation questionnaire to evaluate based on students’ perception. In this paper, four different classi?cation techniques—decision tree algorithms, support vector machines, arti?cial neural networks, and discriminant analysis—are used to build classi?er models. Their performances are compared over a data set composed of responses of students to a real course evaluation questionnaire using accuracy, precision, recall, and speci?city performance metrics. Although all the classi?er models show comparably high classi?cation performances, C5.0 classi?er is the best with respect to accuracy, precision, and speci?city. In addition, an analysis of the variable importance for each classi?er model is done. Accordingly, it is shown that many of the questions in the course evaluation questionnaire appear to be irrelevant. Furthermore, the analysis shows that the instructors’ success based on the students’ perception mainly depends on the interest of the students in the course. The ?ndings of this paper indicate the effectiveness and expressiveness of data mining models in course evaluation and higher education mining. Moreover, these ?ndings may be used to improve the measurement instruments.
关键词： linear discriminant analysis,Arti?cial neural networks,support vector machines,decision trees,classi?cation algorithms,performance evaluation
更新于2025-09-23 15:19:57
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Optimization of cone beam computed tomography image quality in implant dentistry
摘要： This study was conducted to optimize the cone beam computed tomography image quality in implant dentistry using both clinical and quantitative image quality evaluation with measurement of the radiation dose. A natural bone human skull phantom and an image quality phantom were used to evaluate the images produced after changing the exposure parameters (kVp and mA). A 10 × 5 cm2 field of view was selected for average adult. Five scans were taken with varying kVp (70–90 kVp) first at fixed 4 mA. After assessment of the scans and selecting the best kVp, nine scans were taken with 2–12 mA, and the kVp was fixed at the optimal value. A clinical assessment of the implant‐related anatomical landmarks was done in random order by two blinded examiners. Quantitative image quality was assessed for noise/uniformity, artifact added value, contrast‐to‐noise ratio, spatial resolution, and geometrical distortion. A dosimetry index phantom and thimble ion chamber were used to measure the absorbed dose for each scan setting. The anatomical landmarks of the maxilla had good image quality at all kVp settings. To produce good quality images, the mandibular landmarks demanded higher exposure parameters than the maxillary landmarks. The quantitative image quality values were acceptable at all selected exposure settings. Changing the exposure parameters does not necessarily produce higher image quality outcomes but does affect the radiation dose to the patient. The image quality could be optimized for implant treatment planning at lower exposure settings and dose than the default settings.
关键词： radiation dose,image quality,clinical image evaluation,dental CBCT,implant treatment planning
更新于2025-09-23 15:19:57
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Fast non-local means noise reduction algorithm with acceleration function for improvement of image quality in gamma camera system: a phantom study
摘要： Gamma-ray images generally suffer from a lot of noise because of low photon detection in the gamma camera system. The purpose of this study is to improve the image quality in gamma-ray images using a gamma camera system with a fast nonlocal means (FNLM) noise reduction algorithm with an acceleration function. The designed FNLM algorithm is based on local region considerations, including the Euclidean distance in the gamma-ray image and use of the encoded information. To evaluate the noise characteristics, the normalized noise power spectrum (NNPS), contrast-to-noise ratio (CNR), and coefficient of variation (COV) were used. According to the NNPS result, the lowest values can be obtained using the FNLM noise reduction algorithm. In addition, when the conventional methods and the FNLM noise reduction algorithm were compared, the average CNR and COV using the proposed algorithm were approximately 2.23 and 7.95 times better than those of the noisy image, respectively. In particular, the image-processing time of the FNLM noise reduction algorithm can achieve the fastest time compared with conventional noise reduction methods. The results of the image qualities related to noise characteristics demonstrated the superiority of the proposed FNLM noise reduction algorithm in a gamma camera system.
关键词： Medical application,Noise reduction algorithm,Evaluation of image quality,Total variation noise reduction method,Gamma camera system
更新于2025-09-23 15:19:57
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Unsupervised evaluation-based region merging for high resolution remote sensing image segmentation
摘要： Image segmentation has a remarkable influence on the classification accuracy of object-based image analysis. Accordingly, how to raise the performance of remote sensing image segmentation is a key issue. However, this is challenging, primarily because it is difficult to avoid over-segmentation errors (OSE) and under-segmentation errors (USE). To solve this problem, this article presents a new segmentation technique by fusing a region merging method with an unsupervised segmentation evaluation technique called under- and over-segmentation aware (UOA), which is improved by using edge information. Edge information is also used to construct the merging criterion of the proposed approach. To validate the new segmentation scheme, five scenes of high resolution images acquired by Gaofen-2 and Ziyuan-3 multispectral sensors are chosen for the experiment. Quantitative evaluation metrics are employed in the experiment. Results indicate that the proposed algorithm obtains the lowest total error (TE) values for all test images (0.3791, 0.1434, 0.7601, 0.7569, 0.3169 for the first, second, third, fourth, fifth image, respectively; these values are averagely 0.1139 lower than the counterparts of the other methods), as compared to six state-of-the-art region merging-based segmentation approaches, including hybrid region merging, hierarchical segmentation, scale-variable region merging, size-constrained region merging with edge penalty, region merging guided by priority, and region merging combined with the original UOA. Moreover, the performance of the proposed method is better for artificial-object-dominant scenes than the ones mainly covering natural geo-objects.
关键词： region merging,high resolution remote sensing image,image segmentation,over- and under-segmentation aware,unsupervised evaluation
更新于2025-09-19 17:15:36
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ALK positive lung cancer identification and targeted drugs evaluation using microscopic hyperspectral imaging technique
摘要： It is important to distinguish ALK positive lung cancer from ALK negative lung cancer and to monitor the efficacy of targeted drugs. This paper applies a microscopic hyperspectral imaging technique to identify ALK positive lung cancer cells and evaluate the therapeutic effect. The hyperspectral images of five groups of lung tissues are captured by the home-made microscopic hyperspectral imaging system. A preprocessing algorithm is proposed to reduce obvious banding noise and noise particles from original data. Then a segmentation algorithm, which assembles Supported Vector Machine (SVM) and Majority analysis together with the Clumping processing, is presented. The ALK positive and negative lung cancers can be distinguished by both the fluctuation of spectral curves and the relative proportion between cytoplasm and cell nucleus. In addition, the treatment efficacy can be surveyed in the same way. The experimental results show that the relative proportion of cytoplasm in Group ALK-neg is 77.3%, while that in Group ALK-pos is 40.6%. It is obvious that there exist differences in contents and spectra between Group ALK-neg and Group ALK-pos. Moreover, the experimental results of quantitative analysis and spectral curves analysis show that ALK positive lung cancer cells treated with the low concentration of targeted drugs will be developed towards the ALK negative lung cancer. This paper shows the potential of using hyperspectral images to detect the ALK positive lung cancer cells and evaluate the therapeutic effect of targeted drugs.
关键词： Spectral analysis,Therapeutic effect evaluation,Microscopic hyperspectral imaging,ALK positive lung cancer
更新于2025-09-19 17:15:36
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Features of Undiagnosed Breast Cancers at Screening Breast MR Imaging and Potential Utility of Computer-Aided Evaluation
摘要： Objective: To retrospectively evaluate the features of undiagnosed breast cancers on prior screening breast magnetic resonance (MR) images in patients who were subsequently diagnosed with breast cancer, as well as the potential utility of MR-computer-aided evaluation (CAE). Materials and Methods: Between March 2004 and May 2013, of the 72 consecutive pairs of prior negative MR images and subsequent MR images with diagnosed cancers (median interval, 32.8 months; range, 5.4–104.6 months), 36 (50%) had visible findings (mean size, 1.0 cm; range, 0.3–5.2 cm). The visible findings were divided into either actionable or underthreshold groups by the blinded review by 5 radiologists. MR imaging features, reasons for missed cancer, and MR-CAE features according to actionability were evaluated. Results: Of the 36 visible findings on prior MR images, 33.3% (12 of 36) of the lesions were determined to be actionable and 66.7% (24 of 36) were underthreshold; 85.7% (6 of 7) of masses and 31.6% (6 of 19) of non-mass enhancements were classified as actionable lesions. Mimicking physiologic enhancements (27.8%, 10 of 36) and small lesion size (27.8%, 10 of 36) were the most common reasons for missed cancer. Actionable findings tended to show more washout or plateau kinetic patterns on MR-CAE than underthreshold findings, as the 100% of actionable findings and 46.7% of underthreshold findings showed washout or plateau (p = 0.008). Conclusion: MR-CAE has the potential for reducing the number of undiagnosed breast cancers on screening breast MR images, the majority of which are caused by mimicking physiologic enhancements or small lesion size.
关键词： False negative breast cancer,Computer-aided evaluation,Magnetic resonance imaging
更新于2025-09-19 17:15:36