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81.
Ant colony optimization (ACO) algorithms have been successfully applied in data classification, which aim at discovering a list of classification rules. However, due to the essentially random search in ACO algorithms, the lists of classification rules constructed by ACO-based classification algorithms are not fixed and may be distinctly different even using the same training set. Those differences are generally ignored and some beneficial information cannot be dug from the different data sets, which may lower the predictive accuracy. To overcome this shortcoming, this paper proposes a novel classification rule discovery algorithm based on ACO, named AntMinermbc, in which a new model of multiple rule sets is presented to produce multiple lists of rules. Multiple base classifiers are built in AntMinermbc, and each base classifier is expected to remedy the weakness of other base classifiers, which can improve the predictive accuracy by exploiting the useful information from various base classifiers. A new heuristic function for ACO is also designed in our algorithm, which considers both of the correlation and coverage for the purpose to avoid deceptive high accuracy. The performance of our algorithm is studied experimentally on 19 publicly available data sets and further compared to several state-of-the-art classification approaches. The experimental results show that the predictive accuracy obtained by our algorithm is statistically higher than that of the compared targets.  相似文献   
82.
PurposeTo determine whether pancorneal rigid gas-permeable toric edge contact lenses (pancorneal RGP-CL) fitting could be improved by using non-central corneal shape predictors, and to compare these parameters with respect to age and gender in patients with keratoconus.MethodsThe current study was a retrospective study including patients with clinically evident keratoconus (on videokeratography) from three medical centres located in the Netherlands. Medical history, visual acuity, refraction, and contact lens characteristics were documented. All participants underwent ophthalmic examination including measurement of K-values (steepest, flattest, mean, as a non-central parameter the minimum radius [K-minimum], and all combined) using corneal topography. Fitting of contact lenses was based on the fluorescence pattern as seen during slitlamp examination.ResultsA total of 378 eyes of 218 patients with keratoconus were included. Of these, 257 (68%) were fitted with a pancorneal RGP-CL. The central K-values, K-steep and K-flat, performed well in predicting the base curve radius, though, for pancorneal RGP-CL the non-central K-minimum added most (35.5%) to the total explained variance in base curve radius. Regarding age and gender, women tended to have larger K-values than men. No differences in K-values were found with respect to age.DiscussionWe found that including the K-minimum as a non-central parameter may improve prediction of the best base curve radius for pancorneal RGP-CL and may reduce the number of trial contact lenses. In line with other studies, suggestive evidence was found for a difference in pattern of progression of keratoconus with gender, but not with age.  相似文献   
83.
Cold chain management can optimize freshness and safety to the consumer end. Within FRISBEE European project (http://frisbee-project.eu) a web-based platform was developed for temperature conditions data collection throughout the chilled and frozen food supply chain. Data including all cold chain stages (industry, distributors, retailers and consumers), were collected. This extensive database comprising more than 14,000 time-Temperature (t–T) profiles can serve as a valuable Cold Chain Management tool. The user can define a sequence of cold chain stages for selected food products. The Cold Chain Predictor (CCP) software based on the Cold Chain Database (CCD) allows calculation of product shelf-life status at different cold chain stages based on existing or user defined kinetic data. Conducted field tests expanded the Cold Chain Database and validated the software. The developed tools offer the potential to run simulation scenarios based on real cold chain data and contribute to effective cold chain improvement and management.  相似文献   
84.
85.
在项目实施过程中,根据当前项目系统和环境的主要矛盾设计相应的控制目标,构造多个试图实现柔性控制的方案,利用问卷调查和专家打分方法形成决策的原始数据,以条件熵度量分析目标的相对重要性,运用双基点法建立柔性控制决策的定量分析方法,以此确定出各方案的轻重缓急顺序,最后通过例子验证了定量分析方法的有效性.  相似文献   
86.
A dense heterogeneous cellular network can effectively increase the system capacity and enhance the network coverage. It is a key technology for the new generation of the mobile communication system. The dense deployment of small base stations not only improves the quality of network service, but also brings about a significant increase in network energy consumption. This paper mainly studies the energy efficiency optimization of the Macro-Femto heterogeneous cellular network. Considering the dynamic random changes of the access users in the network, the sleep process of the Femto Base Stations (FBSs) is modeled as a Semi-Markov Decision Process (SMDP) model in order to save the network energy consumption. And further, this paper gives the dynamic sleep algorithm of the FBS based on the value iteration. The simulation results show that the proposed SMDP-based adaptive sleep strategy of the FBS can effectively reduce the network energy consumption.  相似文献   
87.
中医舌诊八纲辨证神经网络知识库构建   总被引:13,自引:1,他引:12  
根据中医诊断推理对知识的不确定性、不完全性和逻辑推理的模糊性及“软计算”技术的特点出发,探讨了利用“软计算”的方法构建中医诊断神经网络知识库的基本设想,最后在MATLAB中利用现有结构固定的三种神经网络模型分别粗略地构造了中医“八纲辨证”神经网络,并分析其计算结果。说明采用神经网络技术构建中医诊断知识库是完全可行的。  相似文献   
88.
基于HTTP协议参数插入的信息隐藏算法可以将待隐藏的信息嵌入到目前Internet上使用最为广泛的协议数据包中,逃避防火墙等网络安全工具拦截和窜改。经过试验总结出了,为了增强通信的隐秘性,算法设计需要考虑的一些问题。提出了一种多维随机插入算法,增加了通信的隐秘性。为了进一步增加隐秘性和可靠性,待隐藏信息在隐藏之前进行了加密和数字摘要计算。同时针对嵌入算法多维随机性,计算该隐蔽信道的带宽模型,并在试验中进行了验证。  相似文献   
89.
《Ceramics International》2019,45(16):19689-19694
Li–Al–B–Si–O (LABS) glass-ceramics with a sintering temperature of 600 °C were studied for ultra-low temperature co-fired ceramics (ULTCC) applications. The crystal phase of LABS glass-ceramics is dendritic β-spodumene. The permittivity and dielectric loss of LABS glass-ceramics are εr = 5.8 and tgδ = 1.3 × 10−3 at 10 MHz, respectively. The coefficient of thermal expansion (CTE) of LABS glass-ceramics is 3.23 ppm/°C, which is close to that of silicon. The dielectric and thermal properties of LABS glass-ceramics are closely correlated to the degree of its crystallization. The permittivity decreases continually while the dielectric loss decreases first and slightly increases with the increasing of crystallization of β-spodumene. The CTE of LABS glass-ceramics decreases as β-spodumene crystallized from LABS glass. The crystallization kinetic and mechanism of LABS glass-ceramics indicate that the β-spodumene crystallizes in a two-dimensional interfacial growth mechanism due to the migration of Li-ions. The diffusion coefficients derived from energy-dispersive X-ray spectroscopy (EDS) results indicated that both Al and Ag electrodes have good compatibilities with ULTCC tapes, which could reduce the cost of multilayer electro-ceramic devices dramatically by using the ULTCC and base metallization.  相似文献   
90.
叙述了钙基润滑脂的生产原理和过程,及其主要指标。  相似文献   
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