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81.
Abstract. Niche companies are per definition idiosyncratic. They survive in a competitive world by mastering a small market niche, providing what their customers need. This often requires a flexible organization, and the ability to customize products. To be more efficient, many of these companies rely on extensive use of IT, often by installing general Enterprise Resource Planning (ERP) systems. These systems have grown from isolated systems that handle planning based on incoming orders and the component structure of the various products, to systems with ambitions to embrace the total functioning of the company including vendor and customer relation management. In this paper, we present four case studies. One company is a part of a large enterprise, but performs niche functions within this enterprise. The other three are small- or medium-sized enterprises. Each of these performs in small niche markets. Common to all is the fact that they encounter problems with the utilization of their ERP systems. The major problem seems to be that the ERP system has an inherent business model that may not conform to the needs of the company. Without a good understanding of the underlying models and the constraints under which the fundamental algorithms operate, it is difficult to use these systems correctly. Even excellent systems may give bad results if they are applied to situations where they are not suited. Further, the monolithic structure of an ERP system, with a rather complicated parameter setting, is often insufficient to mould the system to the needs of a niche company. We discuss these problems based on our four case studies, and offer alternative approaches that may be considered. 相似文献
82.
Jonas
rtegren Philippe Busson Mikael Lindgren David S. Hermann Per-Otto Arntzen Fredrik Sahlen Mikael Trollss Ulf W. Gedde Anders Hult Lechezar Komitov Sven T. Lagerwall Per Rudquist Bengt Stebler 《Optical Materials》1998,9(1-4):220-225
Second harmonic generation in novel pyroelectric liquid crystal polymers (PLCP) made from a series binary mixtures, was studied using 1100 nm as the fundamental wavelength. The PLCPs were prepared by photo-polymerization of binary mixtures of two monomers which exhibit a smectic C* phase, A2c (4″-(R)-(−)-2-[(10-acrylo-yloxy)decyl]oxy-3-nitrophenyl 4-{4′-[(11-acryloyloxy)-undecyloxy]phenyl}benzoate) and Alb (4″-((R)-(+)-2-octyloxy)-3″-nitrophenyl 4-(4′-(11-acryloyloxy)undecyloxy)-phenyl)-benzoate). The highest d16 and d23 coefficients were found to be in the range 0.65–0.8 pm/V, and differed depending on the detailed preparation of the sample. All cases of polymers formed from the chiral smectic C* phase showed an SHG-signal with no external field present, indicating that polar order became fixed. The SHG-signal was found to increase with the tilt angle of the FLC molecules. 相似文献
83.
Relationship between collagen characteristics,lipid content and raw and cooked texture of meat from young bulls of fifteen European breeds 总被引:1,自引:0,他引:1
Mette Christensen Per Ertbjerg Sebastiana Failla Carlos Sañudo R. Ian Richardson Geoff R. Nute José L. Olleta Begoña Panea Pere Albertí Manuel Juárez Jean-François Hocquette John L. Williams 《Meat science》2011
Variations in texture were determined for 10 day aged raw and cooked Longissimus thoracis (LT) muscle from 436 bulls of 15 European cattle breeds slaughtered at an age of 13–16 months. Variations in texture were related to differences in pH 24 h post-mortem, sarcomere length, collagen characteristics and lipid content. The shear force of cooked meat samples varied from 43.8 to 67.4 N/cm2. Simmental, Highland and Marchigiana cattle had the highest shear force values and Avileña-Negra Ibérica, Charolais, Casina and Pirenaica cattle had the lowest values. Cooked meat toughness showed a weak negative correlation to lipid content (P < 0.001) but no correlation to collagen characteristics. Raw meat texture measured by compression correlated positively (P < 0.001) with total and insoluble collagen. In conclusion, collagen characteristics showed correlation to raw meat texture but not to cooked meat toughness of LT muscle in European young bulls. 相似文献
84.
Dispersion polymerization of styrene has been performed in CO2-expanded ethanol at ≤9 MPa and 70 °C using PVP as stabilizer. The polymerizations proceeded with good colloidal stability, resulting in spherical particles of diameters of ∼2 μm. Pressurization with CO2 leads to an increase in particle size (∼1 μm in the corresponding CO2-free system), and a decrease in both polymerization rate and molecular weight. The main effect of CO2 is proposed to be its influence on the partitioning of monomer between the continuous and the particle phase–the results indicate that CO2-pressurization causes a reduction in monomer concentration in the particles. Overall, the results are consistent with literature data on the effects of the polarity of the continuous phase in dispersion polymerization of styrene in alcohols and alcohol/water mixtures. 相似文献
85.
Per Flodin 《Polymer Engineering and Science》1998,38(8):1220-1228
The environment and the circumstances leading to the Sephadex group of products for gel filtration (SEC, size exclusion chromatography) are described. The importance of Porath's and the author's experience from zone electrophoresis is stressed. To be able to get high resolution the technique for packing columns was of decisive importance for electrophoresis. It paved the way for the observation of the separation properties of dextran gels. The synthesis of dextran-based gels at AB Pharmacia and the development of varieties of them for varying applications are described together with the project leading to their marketing in 1959. The work of the author on gel filtration is summarized. The story is based on publication and memory. Aids to the latter have been laboratory notebooks and other documents still in the possession of the author. 相似文献
86.
87.
Vamsi Krishna Palukuru Jani Peräntie Mikko Komulainen Timo Tick Heli Jantunen 《Journal of the European Ceramic Society》2010,30(2):389-394
A tunable microwave phase shifter composed of a low-sintering-temperature, screen-printable barium strontium titanate (BST) film and silver metallization was fabricated on an alumina substrate and co-fired at 900 °C for 3 h. The dielectric properties of the films were characterized in a frequency range of 0.8–8 GHz using scattering parameter measurements and a quasi-static coplanar waveguide transmission line model. The temperature dependency of the films was measured through capacitance measurements in a frequency range of 0.5–2.5 GHz. The figure of merit (phase shift/dB of insertion loss) of the phase shifter was found to be 14.6 at 3 GHz with an applied bias field strength of 2.5 V/μm. The performance of the phase shifter is briefly discussed and compared with other phase shifters fabricated by direct screen-printing of BST films. 相似文献
88.
Autogenous deformation and RH-change in perspective 总被引:12,自引:0,他引:12
Autogenous deformation and change of the relative humidity (RH-change) have been described and registered for a century. However, it is only within the last decade that these phenomena have received appreciable attention. The reason for this is that autogenous deformation and autogenous RH-change are phenomena of special importance within high-strength (high-performance) concrete technology, and a significant utilisation of these concretes did not take place until the early 1980s. In the present paper an historical overview of autogenous deformation and RH-change is given. In addition, due to the present status of this research field both terminology and measuring techniques are described in detail. Finally, some expectations for future research in this field are given. 相似文献
89.
Fire retardants may considerably improve the fire properties of wood products, but the durability, e.g. in exterior applications, has not been addressed fully. This paper reviews the existing knowledge and experience mainly from the USA with the aim of supporting further development in Europe. The review is concentrated on pressure impregnated fire retardant treated wood products which have the best opportunities for increased durability. Copyright © 2001 by John Wiley & Sons, Ltd. 相似文献
90.
Per Illum 《International Journal of Project Management》1983,1(3):169-172
The principles of implementing a model for project management and systems development are discussed. Consideration is given to the problems that arise in implementing structured techniques i.e. structured systems analysis and structured systems design, and a proven methodology is recommended, which gives the organization the basic foundation for success in systems development. It also contains a model for project management which includes a guide to the execution of quality and funding reviews throughout the life cycle. 相似文献