1,720,969 research outputs found
Decolorization of Reactive Red 195 solution by electrocoagulation process
Get PDFIn this study, the application of bipolar electrocoagulation (EC) with iron electrode has been assessed for color removal of simulated wastewater containing Reactive Red 195. The influence of initial pH, sodium sulfate concentration, initial dye concentration, electrolysis time, and electric current were examined. The optimum operational parameters were found to be pH =11, concentration of dye = 50 mg L-1, sodium sulfate concentration = 1200 mg L-1, electrolysis time = 5 min and electric current = 4 A. In such condition, color removal efficiency achieved over 99%. This result indicates that EC can be used as an efficient and “green” method for color removal from reactive dye solution.Trong nghiên cứu này, quá trình khử màu nhuộm hoạt tính (Reactive Red 195) được khảo sát bằng hệ thống keo tụ điện hóa điện cực kép, với vật liệu sắt. Các yếu tố ảnh hưởng đến quá trình khử màu như pH, nồng độ màu nhuộm, nồng độ muối Na2SO4, thời gian phản ứng và cường độ dòng được lựa chọn nghiên cứu. Kết quả cho thấy hệ thống điện hóa trên loại gần như hoàn toàn màu nhuộm với hiệu suất đạt trên 99 % tại pH 11, nồng độ màu 50 mgL-1 và nống độ muối Na2SO4 1200 mgL-1 trong khoảng thời gian 5phút. Kết quả trên cho thấy keo tụ điện hóa có thể xem là một phương pháp xử lý hiệu quả và “xanh” trong việc loại bỏ hoàn toàn màu từ nước thải nhuộm hoạt tính
Decolorization of reactive dyeing wastewater by Poly Aluminium Chloride: Research article
Get PDFColor removal of some reactive dyes (Blue 19, Black 5 and Red 195) using a local Poly Aluminium Chloride (PAC) was investigated with Jar-test experiment. The dyes were removed (above 94%) at optimal pH 7 (Red 195) and pH 10 (Blue 19 and Black 5). The PAC dosage of 220 mg/L (Blue 19 and Black 5) and 160 mg/L (Red 195) were found to be best for decreasing dye up to 50 mg/L (Black 5, Red 195) and 100 mg/L (Blue 19). Reaction time and agit ation speed also affected the decolorization process. That result indicates that Vietnamese PAC can be a robust and economical coagulant for discolorization of reactive dyeing process.Chất keo tụ Poly Aluminium Chloride (PAC) sản xuất tại Việt nam được ứng dụng khử màu của một số màu nhuộm hoạt tính phổ biến (Blue 19, Black 5 and Red 195) trên thí nghiệm Jar-test. Kết quả cho thấy màu bị loại gần như hoàn toàn (trên 94 %) tại pH 7 (Red 195) hoặc 10 (Blue 19 và Black 5). Nồng độ PAC đạt hiệu quả tốt nhất tại 220 mg/L (Blue 19 và Black 5) và 160 mg/L (Red 195) ứng với nồng độ màu 50 mg/L (Black 5, Red 195) hay 100 mg/L (Blue 19). Thời gian phản ứng, tốc độ khuấy cũng có tác động đến hiệu suất khử màu. Kết quả nghiên cứu cho thấy PAC sản xuất tại Việt nam không những là một chất keo tụ tốt mà còn rất kinh tế cho việc khử màu hoàn toàn trong nước thải nhuộm hoạt tính
Decolorization of reactive dyeing wastewater by ferrous ammonium sulfate hexahydrate: Research article
Get PDFThis paper presents the result of dyeing solution coagulation with the use of ferrous ammonium sulfate hexah ydrate (FAS). The examined solution contains two reactive dyes: Black 5 and Blue 19. It has been shown that the efficiency of the dye removal depends on the type of dye, coagulation dosage and the initial pH. Our result showed that the increase of initial pH up to 12 enhanced the color removal efficiency; the FAS dose was 280 ml (Black 5) and 180 mg/l (Blue 19) at slow mixing time (15 min), agitation speed 60 rpm, and the initial dye concentration should be 50 and 100 mg/L for Black 5 and Blue 19, respectively.Chất keo tụ sắt (II) amoni sulfate (FAS) được sử dụng khử màu của hai màu nhuộm hoạt tính phổbiến (Blue 19 và Black 5). Kết quả cho thấy, quá trình keo tụ bịảnh hưởng nhiều bởi loại màu nhuộm, nồng độ chất keo tụ và pH của dung dịch đầu vào. Với nồng độ FAS 280 mg/l (Black 5) và 180 mg/l (Blue 19), pH đầu vào dung dịch khoảng 12, thời gian phản ứng 15 phút, tốc độ khuấy 60 vòng/phút ứng với nồng độ màu Black 50 mg/L và blue 100 mg/L dung dịch gần như mất màu hoàn toàn
Density-Softmax: Efficient Test-time Model for Uncertainty Estimation and Robustness under Distribution Shifts
Get PDFSampling-based methods, e.g., Deep Ensembles and Bayesian Neural Nets have
become promising approaches to improve the quality of uncertainty estimation
and robust generalization. However, they suffer from a large model size and
high latency at test-time, which limits the scalability needed for low-resource
devices and real-time applications. To resolve these computational issues, we
propose Density-Softmax, a sampling-free deterministic framework via combining
a density function built on a Lipschitz-constrained feature extractor with the
softmax layer. Theoretically, we show that our model is the solution of minimax
uncertainty risk and is distance-aware on feature space, thus reducing the
over-confidence of the standard softmax under distribution shifts. Empirically,
our method enjoys competitive results with state-of-the-art techniques in terms
of uncertainty and robustness, while having a lower number of model parameters
and a lower latency at test-time.Comment: International Conference on Machine Learning, 202
Density-Regression: Efficient and Distance-Aware Deep Regressor for Uncertainty Estimation under Distribution Shifts
Get PDFMorden deep ensembles technique achieves strong uncertainty estimation
performance by going through multiple forward passes with different models.
This is at the price of a high storage space and a slow speed in the inference
(test) time. To address this issue, we propose Density-Regression, a method
that leverages the density function in uncertainty estimation and achieves fast
inference by a single forward pass. We prove it is distance aware on the
feature space, which is a necessary condition for a neural network to produce
high-quality uncertainty estimation under distribution shifts. Empirically, we
conduct experiments on regression tasks with the cubic toy dataset, benchmark
UCI, weather forecast with time series, and depth estimation under real-world
shifted applications. We show that Density-Regression has competitive
uncertainty estimation performance under distribution shifts with modern deep
regressors while using a lower model size and a faster inference speed.Comment: International Conference on Artificial Intelligence and Statistics,
202
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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