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11.
12.
Kelvin Sim Vivekanand Gopalkrishnan Arthur Zimek Gao Cong 《Data mining and knowledge discovery》2013,26(2):332-397
Subspace clustering finds sets of objects that are homogeneous in subspaces of high-dimensional datasets, and has been successfully applied in many domains. In recent years, a new breed of subspace clustering algorithms, which we denote as enhanced subspace clustering algorithms, have been proposed to (1) handle the increasing abundance and complexity of data and to (2) improve the clustering results. In this survey, we present these enhanced approaches to subspace clustering by discussing the problems they are solving, their cluster definitions and algorithms. Besides enhanced subspace clustering, we also present the basic subspace clustering and the related works in high-dimensional clustering. 相似文献
13.
Kwang-Eun Ko Kwee-Bo Sim 《International Journal of Control, Automation and Systems》2013,11(3):608-613
This paper presents an improved method based on single trial EEG data for the online classification of motor imagery tasks for brain-computer interface (BCI) applications. The ultimate goal of this research is the development of a novel classification method that can be used to control an interactive robot agent platform via a BCI system. The proposed classification process is an adaptive learning method based on an optimization process of the hidden Markov model (HMM), which is, in turn, based on meta-heuristic algorithms. We utilize an optimized strategy for the HMM in the training phase of time-series EEG data during motor imagery-related mental tasks. However, this process raises important issues of model interpretation and complexity control. With these issues in mind, we explore the possibility of using a harmony search algorithm that is flexible and thus allows the elimination of tedious parameter assignment efforts to optimize the HMM parameter configuration. In this paper, we illustrate a sequential data analysis simulation, and we evaluate the optimized HMM. The performance results of the proposed BCI experiment show that the optimized HMM classifier is more capable of classifying EEG datasets than ordinary HMM during motor imagery tasks. 相似文献
14.
雀巢公司位于瑞士柯诺芬根的研发中心开发奶制品。并设计制造工艺。而监测换热器的压力,对于这家研发中心来说具有特殊的挑战性。 相似文献
15.
Software developers often need to understand a large body of unfamiliar code with little or no documentation, no experts to consult, and little time to do it. A post appeared in January 2008 on Slashdot, a technology news Web site, asking for tools and techniques that could help. This article analyzes 301 often passionate and sometimes articulate responses to this query, including the themes and the associated tool recommendations. The most common suggestions were to use a code navigation tool, use a design recovery tool, use a debugger to step through the code, create a runtime trace, use problem-based learning, ask people for help, study the code from top down, and print out all the code. This analysis presents an intriguing snapshot of how software developers in industry go about comprehending big code. 相似文献
16.
Geonwoo Kang Minkyung Kim Huisuk Yang Jiwoo Shin Jeeho Sim Hyeri Ahn Mingyu Jang Youseong Kim Hye Su Min Hyungil Jung 《Advanced functional materials》2023,33(11):2370066
Dissolving microneedle (DMN) is an attractive alternative to parenteral and enteral drug administration owing to its painless self-administration and safety due to non-generation of medical waste. For reproducible and efficient DMN administration, various DMN application methods, such as weights, springs, and electromagnetic devices, have been studied. However, these applicators have complex structures that are complicated to use and high production costs. In this study, a latch applicator that consists of only simple plastic parts and operates via thumb force without any external complex device is developed. Protrusion-shaped latches and impact distances are designed to accumulate thumb force energy through elastic deformation and to control impact velocity. The optimized latch applicator with a pressing force of 25 N and an impact velocity of 5.9 m s−1 fully inserts the drug-loaded tip of the two-layered DMN into the skin. In an ovalbumin immunization test, DMN with the latch applicator shows a significantly higher IgG antibody production rate than that of intramuscular injection. The latch applicator, which provides effective DMN insertion and a competitive price compared with conventional syringes, has great potential to improve delivery of drugs, including vaccines. 相似文献
17.
Guilherme Ferreira Gomes Camila Aparecida Diniz Sebastião Simões da CunhaJr. Antonio Carlos AncelottiJr. 《Journal of Failure Analysis and Prevention》2017,17(4):740-749
The investigation of possible failures in composite materials is a matter of very great importance, and the Tsai-Wu criterion is an effective criterion for analyzing those flaws in anisotropic materials and defining whether the material at a given load will or will not suffer structural failure. In this study, an optimization procedure is proposed to minimize the maximum value of Tsai-Wu of laminated composite tubes subject to axial loading. Artificial neural networks and genetic algorithms are chosen as optimization tools. The results of this study show that the developed algorithm converges faster. Then, the maximum Tsai-Wu value is used as the objective function and the fiber orientations are the constraints in the optimization process. The results yielded by them are compared and discussed. Optimal results are compared with respect to the usual initial design. The design approach is recommended for structures where composites are the key load-carrying members such as orthopedic prosthesis. 相似文献
18.
Kyung Seob Lim Jun-Kyu Park Myung Ho Jeong Jae-Woon Nah Dae Sung Park Jong Min Kim Jung Ha Kim So Youn Lee Eun Jae Jang Suyoung Jang Hyun Kuk Kim Doo Sun Sim Keun-Ho Park Young Joon Hong Youngkeun Ahn Jung Chaee Kang 《Journal of materials science. Materials in medicine》2016,27(4):66
The aim of this study was to evaluate antiproliferative sirolimus- and antioxidative alpha-lipoic acid (ALA)-eluting stents using biodegradable polymer [poly-l-lactic acid (PLA)] in a porcine coronary overstretch restenosis model. Forty coronary arteries of 20 pigs were randomized into four groups in which the coronary arteries had a bare metal stent (BMS, n = 10), ALA-eluting stent with PLA (AES, n = 10), sirolimus-eluting stent with PLA (SES, n = 10), or sirolimus- and ALA-eluting stent with PLA (SAS, n = 10). A histopathological analysis was performed 28 days after the stenting. The ALA and sirolimus released slowly over 30 days. There were no significant differences between groups in the injury or inflammation score; however, there were significant differences in the percent area of stenosis (56.2 ± 11.78 % in BMS vs. 51.5 ± 12.20 % in AES vs. 34.7 ± 7.23 % in SES vs. 28.7 ± 7.30 % in SAS, P < 0.0001) and fibrin score [1.0 (range 1.0–1.0) in BMS vs. 1.0 (range 1.0–1.0) in AES vs. 2.0 (range 2.0–2.0) in SES vs. 2.0 (range 2.0–2.0) in SAS, P < 0.0001] between the four groups. The percent area of stenosis based on micro-computed tomography corresponded with the restenosis rates based on histopathological stenosis in different proportions in the four groups (54.8 ± 7.88 % in BMS vs. 50.4 ± 14.87 % in AES vs. 34.5 ± 7.22 % in SES vs. 28.9 ± 7.22 % in SAS, P < 0.05). SAS showed a better neointimal inhibitory effect than BMS, AES, and SES at 1 month after stenting in a porcine coronary restenosis model. Therefore, SAS with PLA can be a useful drug combination for coronary stent coating to suppress neointimal hyperplasia. 相似文献
19.
Mónica Giménez‐Marqués Elena Bellido Thomas Berthelot Teresa Simón‐Yarza Tania Hidalgo Rosana Simón‐Vázquez África González‐Fernández José Avila Maria Carmen Asensio Ruxandra Gref Patrick Couvreur Christian Serre Patricia Horcajada 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(40)
Controlling the outer surface of nanometric metal–organic frameworks (nanoMOFs) and further understanding the in vivo effect of the coated material are crucial for the convenient biomedical applications of MOFs. However, in most studies, the surface modification protocol is often associated with significant toxicity and/or lack of selectivity. As an alternative, how the highly selective and general grafting GraftFast method leads, through a green and simple process, to the successful attachment of multifunctional biopolymers (polyethylene glycol (PEG) and hyaluronic acid) on the external surface of nanoMOFs is reported. In particular, effectively PEGylated iron trimesate MIL‐100(Fe) nanoparticles (NPs) exhibit suitable grafting stability and superior chemical and colloidal stability in different biofluids, while conserving full porosity and allowing the adsorption of bioactive molecules (cosmetic and antitumor agents). Furthermore, the nature of the MOF–PEG interaction is deeply investigated using high‐resolution soft X‐ray spectroscopy. Finally, a cell penetration study using the radio‐labeled antitumor agent gemcitabine monophosphate (3H‐GMP)‐loaded MIL‐100(Fe)@PEG NPs shows reduced macrophage phagocytosis, confirming a significant in vitro PEG furtiveness. 相似文献
20.
String inclusion and non-inclusion problems have been vigorously studied in such diverse fields as molecular biology, data compression, and computer security. Among the well-known string inclusion or non-inclusion notions, we are interested in the longest common nonsuperstring. Given a set of strings, the longest common nonsuperstring problem is finding the longest string that is not a superstring of any string in the given set. It is known that the longest common nonsuperstring problem is solvable in polynomial time.In this paper, we propose an efficient algorithm for the longest common nonsuperstring problem. The running time of our algorithm is linear with respect to the sum of the lengths of the strings in the given set, using generalized suffix trees. 相似文献