790 research outputs found
Pengiraan Persentil Taburan Panjang Larian bagi Carta Kawalan Purata Bergerak Berpemberat Eksponen Multivariat
Prabhu dan Runger (1997) telah mengemukakan cadangan dalam pemilihan
parameter-parameter untuk skema carta kawalan purata bergerak berpemberat
eksponen multivariat (MEWMA). Walau bagaimanapun, cadangan tersebut
hanya berdasarkan prestasi panjang larian purata (average run length - ARL).
Oleh itu, dalam makalah ini, kami akan mengira nilai-nilai persentil untuk
taburan panjang larian bagi pelbagai skema carta kawalan MEWMA yang
dikemukakan oleh Prabhu dan Runger (1997). Persentil-persentil yang dikira
akan membekalkan maklumat tambahan seperti kekerapan isyarat luar kawalan
palsu yang awal (early false out of control signals), panjang larian median
(median run length - MRL) dan kepencongan taburan panjang larian untuk
sesuatu skema tertentu. Maklumat-maklumat tambahan ini mungkin berguna
dalam membekalkan jurutera kawalan mutu pengetahuan mendalam dan
lengkap tentang sesuatu skema carta kawalan MEWMA yang dipilih berdasarkan
cadangan Prabhu dan Runger (1997)
Dimethyl 4-(4-ethoxyphenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate
In the title molecule, C19H23NO5, the dihedral angle formed by the benzene ring and the planar part of the dihydropyridine ring is 83.52 (5)°. The dihydropyridine ring adopts a flattened boat conformation. In the crystal, molecules are linked by N—H⋯O hydrogen bonds, generating chains running parallel to [100]. The crystal structure is consolidated by C—H⋯O contacts
1-[3-(4-Chlorophenyl)-5-(4-methoxyphenyl)-4,5-dihydro-1H-pyrazol-1-yl]butan-1-one
In the title compound, C20H21ClN2O2, the benzene rings form dihedral angles of 6.35 (5) and 81.82 (5)° with the mean plane of the 4,5-dihydro-1H-pyrazole ring (r.m.s. deviation = 0.145 Å). This latter ring adopts an envelope conformation with the CH grouping as the flap. The dihedral angle between the benzene rings is 75.63 (4)°. In the crystal, molecules are linked by C—H⋯Cl and C—H⋯O hydrogen bonds into chains along [-201]. The crystal structure also features C—H⋯π interactions
N-(2,6-Dichlorophenyl)-2-(naphthalen-1-yl)acetamide
In the title compound, C18H13Cl2NO, the naphthalene ring system and the benzene ring form dihedral angles of 74.73 (13) and 62.53 (16)°, respectively, with the acetamide grouping [maximum deviation = 0.005 (3) Å]. The naphthalene ring system forms a dihedral angle of 75.14 (13)° with the benzene ring. In the crystal, molecules are linked by N—H⋯O hydrogen bonds, forming C(4) chains propagating in [010]. The O atom also accepts two C—H⋯O interactions
1-[5-(4-Chlorophenyl)-3-(4-hydroxyphenyl)-4,5-dihydro-1H-pyrazol-1-yl]ethanone
In the title compound, C17H15ClN2O2, the benzene rings form dihedral angles of 89.56 (5) and 5.87 (5)° with the mean plane of the pyrazoline ring (r.m.s. deviation = 0.084 Å). The dihedral angle between the two benzene rings is 87.57 (5)°. In the crystal, molecules are linked by O—H⋯O and C—H⋯O hydrogen bonds into a helical chain along the c axis. Between the chains weak C—H⋯N and C—H⋯O interactions are present. The crystal studied was an inversion twin with a domain ratio of 0.72 (4):0.28 (4)
Intelligent Financial Fraud Detection Practices: An Investigation
Financial fraud is an issue with far reaching consequences in the finance
industry, government, corporate sectors, and for ordinary consumers. Increasing
dependence on new technologies such as cloud and mobile computing in recent
years has compounded the problem. Traditional methods of detection involve
extensive use of auditing, where a trained individual manually observes reports
or transactions in an attempt to discover fraudulent behaviour. This method is
not only time consuming, expensive and inaccurate, but in the age of big data
it is also impractical. Not surprisingly, financial institutions have turned to
automated processes using statistical and computational methods. This paper
presents a comprehensive investigation on financial fraud detection practices
using such data mining methods, with a particular focus on computational
intelligence-based techniques. Classification of the practices based on key
aspects such as detection algorithm used, fraud type investigated, and success
rate have been covered. Issues and challenges associated with the current
practices and potential future direction of research have also been identified.Comment: Proceedings of the 10th International Conference on Security and
Privacy in Communication Networks (SecureComm 2014
N-(3,5-Dichlorophenyl)-2-(naphthalen-1-yl)acetamide
In the title compound, C18H13Cl2NO, the naphthalene ring system [maximum deviation = 0.038 (4) Å] and the benzene ring form dihedral angles of 69.5 (2) and 37.2 (2)°, respectively, with the essentially planar acetamide unit [maximum deviation = 0.004 (4) Å]. The naphthalene ring system forms a dihedral angle of 52.36 (18)° with the benzene ring. In the crystal, molecules are linked via intermolecular N—H⋯O hydrogen bonds, forming chains along [001]
N-(4-Bromophenyl)-2-(naphthalen-1-yl)acetamide
In the title compound, C18H14BrNO, the naphthalene ring system and the benzene ring form dihedral angles of 78.8 (2) and 19.7 (2)°, respectively, with the acetamide C—C(=O)—N plane. The naphthalene ring system forms a dihedral angle of 64.88 (19)° with the benzene ring. In the crystal, molecules are linked via intermolecular bifurcated (N,C)—H⋯O hydrogen bonds, generating an R
2
1(6) ring motif, forming chains along the b axis
Cluster Performance reconsidered: Structure, Linkages and Paths in the German Biotechnology Industry, 1996-2003
This paper addresses the evolution of biotechnology clusters in Germany between 1996 and 2003, paying particular attention to their respective composition in terms of venture capital, basic science institutions and biotechnology firms. Drawing upon the significance of co-location of "money and ideas", the literature stressing the importance of a cluster's openness and external linkages, and the path dependency debate, the paper aims to analyse how certain cluster characteristics correspond with its overall performance. After identifying different cluster types, we investigate their internal and external interconnectivity in comparative manner and draw on changes in cluster composition. Our results indicate that the structure, i.e. to which group the cluster belongs, and the openness towards external knowledge flows deliver merely unsystematic indications with regard to a cluster's overall success. Its ability to change composition towards a more balanced ratio of science and capital over time, on the other hand, turns out as a key explanatory factor. Hence, the dynamic perspective proves effective illuminating cluster growth and performance, where our explorative findings provide a promising avenue for further evolutionary research
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