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121.
Integrating products and services to customized solutions can help firms to differentiate from their competitors. In practice, however, various companies fall short in extracting value from their customers. Therefore this paper focuses on pricing aspects as central means for value appropriation in the context of solutions. Following the resource-based view of the firm, we adopt a process-oriented perspective on pricing practices in order to identify crucial factors and activities. Based on 15 in-depth interviews with practitioners from various industries we derive six steps of a price management process for value appropriation in the context of solution selling and present critical activities and routines within each step. 相似文献
122.
Niklas Blum Thomas Magedanz Florian Schreiner Sebastian Wahle 《Journal of Network and Systems Management》2009,17(1-2):33-52
Although IP Multimedia Subsystem (IMS) based Next Generation Networks (NGNs) are already emerging as the common session control platform for converging fixed, mobile and cable networks, harmonized solutions for the management of these converged platforms have still got to be developed. This document describes a hands-on approach to NGN Management. Started with IMS specific management systems, succeeding research had to take into account the importance of the management of NGN SDPs as well. This work shows that the hybrid nature of an NGN, where services can be delivered at the IMS layer, by SIP signaling mechanisms, as well as at the SDP, via Web Services, requires a harmonized management approach. Taking into account Service Oriented Architecture (SOA) principles and policy based model driven architectures, this work shows that a unification of service composition and service management already at the workflow creation level, bares significant benefits in terms of automation and harmonization. Following the SOA paradigm, the approach presented here does not differentiate between business process management (BPM) and management process management. Focusing on Telemanagement Forum’s enhanced Telecom Operations Map service fulfillment and service assurance operations, this document describes an New Generation Software and Services (NGOSS) based implementation of a unified Operation Support System (OSS) for NGNs that encompasses many problems of former stovepipe management solutions in terms of automation, flexibility and manageability. 相似文献
123.
The ability to reliably merge independent updates of a document is a crucial prerequisite to efficient collaboration in office work. However, merge support for common office document standards like OpenDocument or OfficeOpenXML is still in its infancy. In this paper, we present a consistent versioning model for XML documents in general including merge support. This is achieved by using context-aware fingerprints that identify edit operations and allow for a conflict detection. We show how to extract tracked changes from office documents and map them on our delta model. Experimental results indicate that our fingerprinting technique is efficient and reliable. 相似文献
124.
An important problem in agent verification is a lack of proper understanding of the relation between agent programs on the
one hand and agent logics on the other. Understanding this relation would help to establish that an agent programming language
is both conceptually well-founded and well-behaved, as well as yield a way to reason about agent programs by means of agent
logics. As a step toward bridging this gap, we study several issues that need to be resolved in order to establish a precise
mathematical relation between a modal agent logic and an agent programming language specified by means of an operational semantics. In this paper, we present an agent programming theory that provides both an agent programming language as well as a corresponding agent verification logic to verify agent programs.
The theory is developed in stages to show, first, how a modal semantics can be grounded in a state-based semantics, and, second, how denotational semantics can be used to define the mathematical relation connecting the logic and agent programming language. Additionally, it is
shown how to integrate declarative goals and add precompiled plans to the programming theory. In particular, we discuss the
use of the concept of higher-order goals in our theory. Other issues such as a complete axiomatization and the complexity
of decision procedures for the verification logic are not the focus of this paper and remain for future investigation.
Part of this research was carried out while the first author was affiliated with the Nijmegen Institute for Cognition and
Information, Radboud University Nijmegen. 相似文献
125.
Sebastian Klenk Jürgen Dippon Peter Fritz Gunther Heidemann 《Information Systems Frontiers》2009,11(4):391-403
Medical data mining is currently actively pursued in computer science and statistical research but not in medical practice.
The reasons therefore lie in the difficulties of handling and statistically analyzing medical data. We have developed a system
that allows practitioners in the field to interactively analyze their data without assistance of statisticians or data mining
experts. In the course of this paper we will introduce data mining of medical data and show how this can be achieved for survival
data. We will demonstrate how to solve common problems of interactive survival analysis by presenting the Online Clinical
Data Mining (OCDM) system. Thereby the main focus is on similarity based queries, a new method to select similar cases based
on their covariables and the influence of these on their survival. 相似文献
126.
The current Web Services Agreement specification draft proposes a simple request-response protocol for agreement creation
only addressing bilateral offer exchanges. This paper proposes a framework augmenting this WS-Agreement to enable negotiations
according to a variety of bilateral and multilateral negotiation protocols. The framework design is based on a thorough analysis
of taxonomies for negotiations from the literature in order to allow for capturing a variety of different negotiation models
within a single, WS-Agreement compatible, framework. In order to provide for the intended flexibility, the proposed protocol
takes a two-stage approach: a meta-protocol is conducted among interested parties to agree on a common negotiation protocol
first before the real negotiation is carried out in the second step due to the protocol established in the first step. 相似文献
127.
C. Amatore A. Jutand G. Meyer P. Bourhis F. Machetto J. -M. Mallet P. Sinaÿ C. Tabeur Y. -M. Zhang 《Journal of Applied Electrochemistry》1994,24(8):725-729
Summary
O-glycosides were synthesized by electrochemical oxidation of phenylS-glycosides in the presence of primary alcohols in acetonitrile. Similarly, a -linked disaccharide was obtained selectively by oxidation of phenylS-glycoside in the presence of a sugar alcohol. Electrosyntheses were performed under controlled potential or at constant current, in an undivided cell, on a large scale. 1 to 60 g of phenylS-glycosides in 0.5 to 1 dm3 of acetonitrile were converted with chemical yields in the range of 65–75%. 相似文献
128.
MB Hossain D van der Helm FJ Schmitz EO Pordesimo RA Magarian KL Meyer LB Overacre BW Day 《Canadian Metallurgical Quarterly》1994,37(11):1670-1683
Molecular structures and conformational characteristics of a series of 1,1-dichloro-2,2,3-triarylcyclopropanes (DTACs), which were reported previously to be distinctly antiestrogenic and inhibitors of the estrogen-receptor-positive MCF-7 human breast cancer cells in culture, are reported. In addition, structural and conformational features of the DTACs were compared to the first-known nonsteroidal antiestrogen, MER25, and the clinically useful antiestrogen Tamoxifen. The molecular structures of four DTAC compounds were determined by X-ray diffraction. Crystallographic structures show that the DTAC molecules have nearly the same relative conformation for the three aryl rings which is designated as a "nonpropeller" conformation in contrast to the observed "propeller" conformation for the three rings in all known triarylethylenes. Systematic conformational searches were performed to find the conformational preferences of DTACs, MER25, and Tamoxifen using idealized model compounds built from their respective crystal structure. Energy-minimization and conformational-search studies demonstrated that all DTAC molecules have a common, single global minimum energy conformer for their central core containing the dichlorotriarylcyclopropyl system, which is similar to that found in their crystal structures. Conformational search of MER25 showed that the molecule can assume a number of low-energy conformers of which two, one anti (A1) and one gauche (G1A), have about the same energy. The anti conformation is similar to the one observed in its crystal structure and resembles the estrogenic E-isomer of Tamoxifen, while the lowest energy gauche conformer of MER25 resembles more closely the antiestrogenic Z-isomer of Tamoxifen. NMR spectroscopic analysis of MER25 showed that the molecule exists predominantly in the anti conformation in solution. A comparative review of the structural features and bioactivities of Tamoxifen, DTACs, and MER25 provides a possible explanation for their low estrogen receptor binding affinity which is common to these compounds together with their antiestrogenic activity. 相似文献
129.
JM Hougard P Poudiougo H Agoua KL Akpoboua C Back L Yaméogo R Meyer D Quillévéré 《Canadian Metallurgical Quarterly》1994,1(4):295-303
After a brief presentation of the Onchocerciasis Control Programme in West Africa (OCP), the authors realize the health and socioeconomic consequences that could follow a cessation of larvicide treatment before 2002 in the south-eastern and western extensions of the Programme. Taking into account that OCP activities are theoretically supported until 1997, but aware of financial constraints that will probably increase from now to 2002, this paper proposes an a minima estimation of the residual vector control activities for a "phasing out" spread out for five years (1998-2002). These estimations essentially concern the larvicide coverage, the insecticides used, the entomological surveillance, the logistical support and their financial aspects. As far as 48 U.S. $ million amount for 5 years are concerned, the budget allocated for vector control activities should not exceed the third of the global amount allocated to OCP for the actual fourth financial phase of the Programme (1992-1997). 相似文献
130.
Retrospective correction of intensity inhomogeneities in MRI 总被引:4,自引:0,他引:4
Medical imaging data sets are often corrupted by multiplicative inhomogeneities, often referred to as nonuniformities or intensity variations, that hamper the use of quantitative analyses. The authors describe an automatic technique that not only improves the worst situations, such as those encountered with magnetic resonance imaging (MRI) surface coils, but also corrects typical inhomogeneities encountered in routine volume data sets, such as MRI head scans, without generating additional artifact. Because the technique uses only the patient data set, the technique can be applied retrospectively to all data sets, and corrects both patient independent effects, such as rf coil design, and patient dependent effects, such as attenuation of overlying tissue experienced both in high field MRI and X-ray computed tomography (CT). The authors show results for several MRI imaging situations including thorax, head, and breast. Following such corrections, region of interest analyses, volume histograms, and thresholding techniques are more meaningful. The value of such correction algorithms may increase dramatically with increased use of high field strength magnets and associated patient-dependent rf attenuation in overlying tissues. 相似文献