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201.
LiNi1−y
Co
y
O2 samples were synthesized at 800 °C and 850 °C, by the solid-state reaction method, using the starting materials LiOH·H2O, Li2CO3, NiO, NiCO3, Co3O4 and CoCO3. The LiNi1−y
Co
y
O2 synthesized using Li2CO3, NiO and Co3O4 exhibited the α-NaFeO2 structure of the rhombohedral system (space group
). As the Co content increased, the lattice parameters a and c decreased. The reason is that the radius of the Co ion is smaller than that of the Ni ion. The increase in c/a shows that
a two-dimensional structure develops better as the Co content increases. The LiNi0.7Co0.3O2 synthesized at 800 °C using LiOH · H2O, NiO and Co3O4 exhibited a larger first discharge capacity of 162 mAh g−1 than the other samples. The cycling performances of the samples with the first discharge capacity larger than 150 mAh g−1 were investigated. LiNi0.9Co0.1O2 synthesized at 850 °C using Li2CO3, NiO and Co3O4 showed excellent cycling performance. Samples with larger first discharge capacity will have a greater tendency for lattice
destruction due to expansion and contraction during intercalation and deintercalation, than samples with smaller first discharge
capacity. As the first discharge capacity increases, the capacity fading rate thus increases. 相似文献
202.
Archives of threaded discussions generated by users in online forums and discussion boards contain valuable knowledge on various topics. However, not all threads are useful because of deliberate abuses, such as trolling and flaming, that are commonly observed in online conversations. The existence of various users with different levels of expertise also makes it difficult to assume that every discussion thread stored online contains high-quality contents. Although finding high-quality threads automatically can help both users and search engines sift through a huge amount of thread archives and make use of these potentially useful resources effectively, no previous work to our knowledge has performed a study on such task. In this paper, we propose an automatic method for distinguishing high-quality threads from low-quality ones in online discussion sites. We first suggest four different artificial measures for inducing overall quality of a thread based on ratings of its posts. We then propose two tasks involving prediction of thread quality without using post rating information. We adopt a popular machine learning framework to solve the two prediction tasks. Experimental results on a real world forum archive demonstrate that our method can significantly improve the prediction performance across all four measures of thread quality on both tasks. We also compare how different types of features derived from various aspects of threads contribute to the overall performance and investigate key features that play a crucial role in discovering high-quality threads in online discussion sites. 相似文献
203.
Young-su Kim Jae Hyeon Kim Hyun Su Lee Han Rim Lee Jong Hoon Park Jin Hyung Park 《Journal of Nuclear Science and Technology》2016,53(12):2040-2048
The Korea Atomic Energy Research Institute (KAERI) has constructed a test-bed facility, named PRIDE (PyRoprocess Integrated inactive DEmonstration), for demonstration of pyroprocessing technology. Even though the PRIDE facility utilizes depleted uranium, instead of actual spent fuel, as process material, it will play an important role not only from the process perspective, but also from the safeguards standpoint. In the present study, a Compton imaging system based on pixelated GAGG:Ce scintillation detectors was constructed and tested to determine its utility for accurate imaging of nuclear material locations and, thus, its applicability as a safeguards monitoring system at the PRIDE facility. In a lab-scale performance evaluation, when the dose rate induced by a 137Cs point-like source was ~0.1 μSv/h, the source location was imaged within 5 min. The image resolutions were 22° and 7.6° for real-time monitoring using a back-projection algorithm and for near-real-time monitoring using a statistical iterative algorithm, respectively. The developed Compton imaging system was finally applied to low-enriched uranium and also to depleted uranium, which latter is the process material of the PRIDE facility, and it was indicated that the Compton imaging system can localize nuclear materials within a few minutes under conditions similar to those prevailing at the PRIDE facility. The results of this study show that the Compton imaging system, and Compton imaging technology in general, has a great potential for utilization as a nuclear material monitoring tool at the PRIDE facility. 相似文献
204.
Some Effective Techniques for Naive Bayes Text Classification 总被引:3,自引:0,他引:3
Sang-Bum Kim Kyoung-Soo Han Hae-Chang Rim Sung Hyon Myaeng 《Knowledge and Data Engineering, IEEE Transactions on》2006,18(11):1457-1466
While naive Bayes is quite effective in various data mining tasks, it shows a disappointing result in the automatic text classification problem. Based on the observation of naive Bayes for the natural language text, we found a serious problem in the parameter estimation process, which causes poor results in text classification domain. In this paper, we propose two empirical heuristics: per-document text normalization and feature weighting method. While these are somewhat ad hoc methods, our proposed naive Bayes text classifier performs very well in the standard benchmark collections, competing with state-of-the-art text classifiers based on a highly complex learning method such as SVM 相似文献
205.
A hybrid genetic algorithm for the job shop scheduling problems 总被引:19,自引:0,他引:19
The Job Shop Scheduling Problem (JSSP) is one of the most general and difficult of all traditional scheduling problems. The goal of this research is to develop an efficient scheduling method based on genetic algorithm to address JSSP. We design a scheduling method based on Single Genetic Algorithm (SGA) and Parallel Genetic Algorithm (PGA). In the scheduling method, the representation, which encodes the job number, is made to be always feasible, the initial population is generated through integrating representation and G&T algorithm, the new genetic operators and selection method are designed to better transmit the temporal relationships in the chromosome, and island model PGA are proposed. The scheduling methods based on genetic algorithm are tested on five standard benchmark JSSP. The results are compared with other proposed approaches. Compared to traditional genetic algorithm, the proposed approach yields significant improvement in solution quality. The superior results indicate the successful incorporation of a method to generate initial population into the genetic operators. 相似文献
206.
207.
Hyun Uk Lee So Young Park Soon Chang Lee Saehae Choi Soonjoo Seo Hyeran Kim Jonghan Won Kyuseok Choi Kyoung Suk Kang Hyun Gyu Park Hee‐Sik Kim Ha Rim An Kwang‐Hun Jeong Young‐Chul Lee Jouhahn Lee 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(2):214-219
Recently, the appeal of 2D black phosphorus (BP) has been rising due to its unique optical and electronic properties with a tunable band gap (≈0.3–1.5 eV). While numerous research efforts have recently been devoted to nano‐ and optoelectronic applications of BP, no attention has been paid to promising medical applications. In this article, the preparation of BP‐nanodots of a few nm to <20 nm with an average diameter of ≈10 nm and height of ≈8.7 nm is reported by a modified ultrasonication‐assisted solution method. Stable formation of nontoxic phosphates and phosphonates from BP crystals with exposure in water or air is observed. As for the BP‐nanodot crystals’ stability (ionization and persistence of fluorescent intensity) in aqueous solution, after 10 d, ≈80% at 1.5 mg mL?1 are degraded (i.e., ionized) in phosphate buffered saline. They showed no or little cytotoxic cell‐viability effects in vitro involving blue‐ and green‐fluorescence cell imaging. Thus, BP‐nanodots can be considered a promising agent for drug delivery or cellular tracking systems. 相似文献
208.
Byoung Un Kang Jae Young Jho Junkyung Kim Sang‐Soo Lee Min Park Soonho Lim Chul Rim Choe 《应用聚合物科学杂志》2001,79(1):38-48
The effect of molecular weight between crosslinks, Mc, on the fracture behavior of rubber‐toughened epoxy adhesives was investigated and compared with the behavior of the bulk resins. In the liquid rubber‐toughened bulk system, fracture energy increased with increasing Mc. However, in the liquid rubber‐toughened adhesive system, with increasing Mc, the locus of joint fracture had a transition from cohesive failure, break in the bond layer, to interfacial failure, rupture of the bond layer from the surface of the substrate. Specimens fractured by cohesive failure exhibited larger fracture energies than those by interfacial failure. The occurrence of transition from cohesive to interfacial failure seemed to be caused by the increase in the ductility of matrix, the mismatch of elastic constant, and the agglomeration of rubber particles at the metal/epoxy interface. When core‐shell rubber, which did not agglomerate at the interface, was used as a toughening agent, fracture energy increased with Mc. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 38–48, 2001 相似文献
209.
Youn Hye Jo Go Woon Choi Mi-Lyang Kim Kyung Rim Sung 《International journal of molecular sciences》2022,23(9)
We characterized Müller cell gliosis induced by the activation of transient receptor potential vanilloid-type 4 (TRPV4) and assessed whether statins could modulate the gliosis. The human Müller cell line, MIO-M1, was used to analyze the gliosis caused by glaucomatous stimulation. To induce Müller gliosis in MIO-M1 cells, GSK101 was used to activate TRPV4, and Müller gliosis was evaluated by analyzing vimentin, nestin, and glial fibrillary acidic protein (GFAP) expression. The expression level of TNF-α was determined by ELISA. To evaluate the GSK101 activation of the NF-κB pathway, p65 phosphorylation was measured by Western blotting, and the nuclear translocation of p65 and IκBα phosphorylation were assessed by immunostaining. To assess the effect of statins on MIO-M1 gliosis, cells were pretreated for 24 h with statins before GSK101 treatment. Vimentin, nestin, and GFAP expression were upregulated by GSK101, while statins effectively inhibited them. The expression of TNF-α was increased by GSK101. The phosphorylation and nuclear translocation of p65 and IκBα phosphorylation, which occurs prior to p65 activation, were induced. Statins suppressed the GSK101-mediated phosphorylation of IκBα and p65 translocation. Statins can mitigate gliosis in the human Müller cell line. Because TRPV4 activation in Müller cells reflects glaucoma pathophysiology, statins may have the potential to prevent RGC death. 相似文献
210.
Ha Gyeong Shin Ha Rim Yang Aerin Yoon Sukmook Lee 《International journal of molecular sciences》2022,23(10)
Cancer is the second leading cause of death worldwide after cardiovascular diseases. Harnessing the power of immune cells is a promising strategy to improve the antitumor effect of cancer immunotherapy. Recent progress in recombinant DNA technology and antibody engineering has ushered in a new era of bispecific antibody (bsAb)-based immune-cell engagers (ICEs), including T- and natural-killer-cell engagers. Since the first approval of blinatumomab by the United States Food and Drug Administration (US FDA), various bsAb-based ICEs have been developed for the effective treatment of patients with cancer. Simultaneously, several potential therapeutic targets of bsAb-based ICEs have been identified in various cancers. Therefore, this review focused on not only highlighting the action mechanism, design and structure, and status of bsAb-based ICEs in clinical development and their approval by the US FDA for human malignancy treatment, but also on summarizing the currently known and emerging therapeutic targets in cancer. This review provides insights into practical considerations for developing next-generation ICEs. 相似文献