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21.
Minimizing False Positives of a Decision Tree Classifier for Intrusion Detection on the Internet 总被引:1,自引:0,他引:1
Satoru Ohta Ryosuke Kurebayashi Kiyoshi Kobayashi 《Journal of Network and Systems Management》2008,16(4):399-419
Machine learning or data mining technologies are often used in network intrusion detection systems. An intrusion detection
system based on machine learning utilizes a classifier to infer the current state from the observed traffic attributes. The
problem with learning-based intrusion detection is that it leads to false positives and so incurs unnecessary additional operation
costs. This paper investigates a method to decrease the false positives generated by an intrusion detection system that employs
a decision tree as its classifier. The paper first points out that the information-gain criterion used in previous studies
to select the attributes in the tree-constructing algorithm is not effective in achieving low false positive rates. Instead
of the information-gain criterion, this paper proposes a new function that evaluates the goodness of an attribute by considering
the significance of error types. The proposed function can successfully choose an attribute that suppresses false positives
from the given attribute set and the effectiveness of using it is confirmed experimentally. This paper also examines the more
trivial leaf rewriting approach to benchmark the proposed method. The comparison shows that the proposed attribute evaluation
function yields better solutions than the leaf rewriting approach.
相似文献
Satoru OhtaEmail: |
22.
Summary
Copolymerization of vinyl chloride (VC) and ethylene with Cp*Ti( OCH3)3/MAO catalyst was investigated. The Cp*Ti( OCH3)3/MAO catalyst initiated the copolymerization of VC with ethylene, although the copolymer yields were low. In the 13C NMR spectra of the copolymers, the peaks based on junction part between VC and ethylene was observed, but the signals were
small. From DSC measurement of the copolymers, only one glass transition temperature was observed. Thus, it is clear that
the copolymerization with Cp*Ti( OCH3)3/MAO catalysts gave the copolymer, and the copolymer consisting of block sequence rather than random copolymer.
Received: 13 November 2002/Revised: 6 January 2003/Accepted: 10 January 2003
Correspondence to Kiyoshi Endo 相似文献
23.
Yuichi Miyahara Kiyoshi Matsubara Zenji Horita Terence G. Langdon 《Metallurgical and Materials Transactions A》2005,36(7):1705-1711
The extrusion/equal channel angular pressing (EX-ECAP) processing procedure, in which magnesium-based alloys are subjected
to extrusion followed by ECAP, was applied to a Mg-7.5 pct Al-0.2 pct Zr alloy prepared by casting. Microstructural inspection
showed the EX-ECAP process was effective in reducing the grain size from ∼21 μm after extrusion to an as-pressed grain size of ∼0.8 μm. It is shown through static annealing that these ultrafine grains are reasonably stable up to 473 K, but grain growth occurs
at higher temperatures. Tensile specimens were cut from the billets prepared by EX-ECAP and testing showed these specimens
exhibited superplasticity at relatively low temperatures with maximum elongations up to >700 pct. By processing through EX-ECAP
to a higher imposed strain and thereby increasing the area fraction of high-angle boundaries, it is demonstrated that there
is a potential for achieving high-strain-rate superplasticity.
This article is based on a presentation made at the Symposium entitled “Phase Transformations and Deformation in Magnesium
Alloys,” which occurred during the Spring TMS meeting, March 14–18, 2004, in Charlotte, NC, under the auspices of the ASM-MSCTS
Phase Transformations Committee. 相似文献
24.
Kiyoshi Matsubara Yuichi Miyahara Zenji Horita Terence G. Langdon 《Metallurgical and Materials Transactions A》2004,35(6):1735-1744
Experiments were conducted to evaluate the utility of a new processing procedure developed for Mg-based alloys in which samples
are subjected to a two-step processing route of extrusion followed by equal-channel angular pressing (designated as EX-ECAP).
The experiments were conducted using a Mg-0.6 wt pct Zr alloy and, for comparison purposes, samples of pure Mg. It is shown
that the potential for successfully using ECAP increases in both materials when adopting the EX-ECAP procedure. For the Mg-Zr
alloy, the use of EX-ECAP produces a grain size of ∼1.4 μm when the pressing is undertaken at 573 K. By contrast, using EX-ECAP with pure Mg at 573 K produces a grain size of ∼26
μm. Tensile testing of the Mg-Zr alloy at 523 and 573 K after processing by EX-ECAP revealed the occurrence of significantly
enhanced ductilities with maximum elongations of ∼300 to 400 pct. 相似文献
25.
26.
Takuya Isomura Akimasa Takeuchi Kenta Shimba Kiyoshi Kotani Yasuhiko Jimbo 《Electrical Engineering in Japan》2014,187(4):42-50
Recently, there has been abundant research using multineuron recording, but there are many problems with extracting the features from the obtained spike time series, which are huge in volume and complex. Here we introduce a new method of estimating synaptic connection strengths between neurons by fitting to the Izhikevich model by maximum likelihood estimation. We demonstrate that our method can estimate connection strengths from spike time series given by a simulated neural ensemble and can estimate nonconnectivity between two independent cultured neuronal networks. These results suggest that our method is applicable to network and plasticity analysis of neuronal networks. 相似文献
27.
Research and Development of the Coprecipitation Process for Lanthanum Germanate Oxyapatite 下载免费PDF全文
Kiyoshi Kobayashi Shouta Kitajima Yukihito Igarashi Tohru Higuchi Yoshio Sakka 《Journal of the American Ceramic Society》2015,98(1):66-70
Although lanthanum germanate oxyapatite (La–Ge–O) has shown good potential for use as a solid electrolyte in energy storage applications, its synthesis has been challenging by either solid‐ or solution‐state methods. In this study, a new synthesis of La–Ge–O was developed through a coprecipitation technique, in which a highly concentrated homogeneous aqueous solution of La and Ge was prepared from aqueous ammonium germanate and lanthanum nitrate solutions with the addition of dilute nitric acid. Several precipitates were formed by pH manipulation, including an amorphous material obtained at pH > 3. Compared to the individual precipitation behaviors of the parent compounds, the amorphous precipitate was formed only from the aqueous two‐component mixture, and appeared to contain both metals. This material was transformed into crystalline mixtures upon heating at 1273 K. The crystalline phases were La2Ge3O9 and hexagonal‐type GeO2 when the precipitate was formed below pH 8, and the La–Ge–O and La2Ge2O7 phases when the precipitate was formed around pH 8. Product formation from the coprecipitate was discussed based on X‐ray diffraction and thermal analyses. The improved availability of La–Ge–O will allow more extensive investigations of its useful properties. 相似文献
28.
Kiyoshi Oguchi Kohei Sanui Naoya Ogata Yoichi Takahashi Tomihiro Nakada 《Polymer Engineering and Science》1989,29(6):353-358
Acetalized poly(vinyl alcohol)s which were synthesized from poly(vinyl alcohol) (PVA) and aldehyde or ketone were evaluated as electron beam (EB) resists, in order to investigate the relationship between EB sensitivity and chemical structures of the polymers. It was found that the acetalized PVAs were easily crosslinked by EB exposure. The main mechanism of crosslinking may be radical reaction at acetal group. The sensitivity of the acetalized PVA depended on the structure of the acetal group. Acetalized PVAs synthesized from benzaldehyde, in which the electron attracting group was substituted on the benzene ring and from linear aliphatic aldehyde having a long alkyl chain, had high sensitivity. A high sensitivity of 7.2 × 10−7 C/cm2 was attained when the acetalized PVA synthesized from p-chloro-benzaldehyde was used. Acetalized PVAs synthesized from PVA and aldehyde having a cyclic structure had an excellent dry etching durability and were suitable as negative EB resists. 相似文献
29.
Saka M Iijima K Nishida M Koma Y Hasegawa N Sato K Kato Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2008,49(3):160-167
The effects of processing and cooking on the levels of pesticide residues in soybean samples were investigated for 14 pesticides in pre-harvest samples. On soaking, the transfer ratios (%, total pesticide residue amount in product/that in soybean) of soaked soybean were greater than 60% for most of the pesticides investigated. The transfer ratio of soymilk ranged from 37% to 92%, and that of tofu ranged from 7% to 63%. The processing factor (Pf, the concentration (mg/kg) of pesticide in product/that in soybean) of tofu ranged from 0.026 to 0.28. These values varied among pesticides. There was a high correlation between the log P(ow) and the transfer ratio of tofu. The test described here should be useful to obtain the transfer ratios of pesticide residues in processing and/or cooking steps. 相似文献
30.
Kiyoshi Kawai Setsuko Takato Masako Ueda Nao Ohnishi Chotika Viriyarattanasak Kazuhito Kajiwara 《International Journal of Food Properties》2017,20(7):1500-1510
The effects of fatty acid, monoacylglycerol, and polyglycerol fatty acid ester with varying chain length in their acyl chains on the extent of complex formation (complex index) and in vitro enzymatic digestibility of gelatinized potato starch were investigated. The complex index increased with increase in the concentration of the ligands (fatty acid, monoacylglycerol, and polyglycerol fatty acid ester), with the plateau in the complex index value depending on the type of ligands. In comparison of complex index among fatty acid-samples, the complex index maximum increased as the chain length increased up to octanoic acid and then decreased. In comparison of complex index among fatty acid-, monoacylglycerol-, and polyglycerol fatty acid ester-samples at each acyl chain, the complex index maximum followed the order polyglycerol fatty acid ester > monoacylglycerol > fatty acid. Fatty acid, monoacylglycerol, and polyglycerol fatty acid ester with long acyl chains greatly reduced the enzymatic hydrolysis of starch. Polyglycerol fatty acid ester with palmitic acid chains was the strongest inhibitor of starch hydrolysis, suggesting that further complex formation may occur during the hydrolysis of gelatinized starch (enzyme-annealing). 相似文献