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This paper is concerned in the end effects on the normal vibrations of a chain molecule with finite length. In Part I we study the mathematical problem of how to solve the eigenvalue problem of the GF matrix of the chain molecule with finite length. Making use of the fact that the force range can be regarded finite we reduce the problem to solving a determinantal equation usually of much lower order than that of the GF matrix through the introduction of auxiliary variables and transfer matrices. We obtain the simple formula for giving an admissible phase difference in which the end effect is taken into account. In Part II, using this formula we analyze the infrared data of Snyder on crystalline normal paraffins C3H8 through C30H62. Our analyses indicate that the formula is generally useful for making extrapolation, interpolation, assignment, and determination of frequency-phase relations from the experimental data of homologous series of chain molecules.

XML (Extensible Markup Language) processing can incur significant runtime overhead in XML-based infrastructural middleware such as Web service application servers. This paper proposes a novel mechanism for efficiently processing similar XML documents. Given a new XML document as a byte sequence, the XML parser proposed in this paper normally avoids syntactic analysis but simply matches the document with previously processed ones, reusing those results. Our parser is adaptive since it partially parses and then remembers XML document fragments that it has not met before. Moreover, it processes safely since its partial parsing correctly checks the well-formedness of documents. Our implementation of the proposed parser complies with the JSR 63 standard of the Java API for XML Processing (JAXP) 1.1 specification. We evaluated Deltarser performance with messages using Google Web services. Comparing to Piccolo (and Apache Xerces), it effectively parses 35% (106%) faster in a server-side use-case scenario, and 73% (126%) faster in a client-side use-case scenario.

This paper discusses the design for an efficient response cache mechanism appropriate for the Web services architecture. The important feature of Web services is its interoperability between heterogeneous platforms. This interoperability is based on widely accepted standards such as XML, SOAP, and WSDL. We describe a response cache mechanism for Web services client middleware without any extensions to these standards so that the client can participate transparently in the existing Web services community. We propose three optimization methods to improve the performance of our response cache. The first optimization is caching the post-parsing representation instead of the XML message itself. The second is caching application objects. For this optimization, we show some copying processes that are dependent on the type of cached objects. The third optimization is for read-only objects. These methods reduce the overhead of XML processing or object copying. We have implemented a prototype of a response cache on Apache-Axis, and evaluated these optimization methods through experiments for Google Web services. Finally, based on the experimental results, we discuss the optimal configuration of these methods based on data types.

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