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21.
Fares A. Ghandour Paulina Swartz Heidi M. Grenek Edward B. Roberts 《Technology Analysis & Strategic Management》2004,16(4):435-455
The number of firms using alliances as part of their corporate venturing or market entry strategies has surged over the past decade. Three common reasons cited for pursuing alliances are technology convergence, market access and alliance partners' complementary resources. This paper contrasts the alliance strategies of HP and IBM, two major competitors in electronic services (i.e. Internet-based 'e- service') businesses, using the Familiarity Matrix as a display tool to portray the strategies. Whereas the HP strategy is to attempt to establish its technology infrastructure as the standard e-services infrastructure on the Internet, IBM aims to position its IBM Global Services, rather than its technology, at the center of this ecosystem. 相似文献
22.
坦努尔坝是约旦的第一座RCC坝。该坝RCC铺筑采用斜层施工,提高工数50%。大坝上游面,下游台阶,阶梯式溢洪道,止水面以及RCC与坝肩石灰岩的交界面均采用GE-RCC。质量控制测试数据表明,该坝达到了国际大坝委员会会刊不久将发表的RCC坝质量标准的优良等级。 相似文献
23.
We propose a new model to estimate the term structure of interest rates using observed on‐the‐run Treasury yields. The new model is an improvement over models that require a priori knowledge of the shape of the yield curve to estimate the term structure. The general form of the model is an exponential function that depends on the estimation of four parameters fit by nonlinear least squares and has straightforward interpretations. In comparing the proposed model with current yield‐curve‐smoothing models, we find that, for the data used, the proposed model does best overall in terms of pricing accuracy both in sample and out of sample. JEL classification: E43, G12 相似文献
24.
Yaser A. Alkulaib Mohammad Najand Ahmad Mashayekh 《Journal of Multinational Financial Management》2009,19(1):43-53
The relaxation of security laws and regulations in emerging markets in the Middle East and North Africa (MENA) provides abundant opportunities for foreign investors. These markets exhibit high-expected returns and substantial volatility. In this paper, we investigate the lead/lag relationship between the MENA countries and regions. We find no market causality or spillover from one country to another in the North Africa region. Our results for the Levant region reveal that there are linkages between stock markets in this region. The results for the Gulf Cooperation Council (GCC) region show that there is more interaction and linkage in the GCC region than in the North Africa and Levant regions. An unexpected result is that UAE's stock market leads all the markets in this region. Finally, we investigate linkages among the three regions. We find that GCC influences the other two regions. 相似文献
25.
Stephanie Stray 《Quality and Quantity》2009,43(1):161-171
That survey research is error prone is not a new idea and different varieties of non-sampling error have been investigated
in the literature as well as consideration being given in many statistics textbooks to the issue of sampling error. The paper
here considers research upon corporate environmental reporting. It compares information provided by corporate environmental
reports with information that survey respondents claim their organization’s environmental report contains. This enables the
accuracy of the claims to be assessed. Consideration is given to two different industries the Water industry and the Energy
industry. Errors due to inaccurate reporting by survey respondents are shown to be relatively infrequent and respondents appear
just about as likely to claim they report information that they do not, in fact, report as to fail to indicate that they report
information that is, in fact, actually reported. 相似文献
26.
27.
O Baeder-Bederski M Dürr M Borneff-Lipp P Kuschk R Netter G Daeschlein P Mosig R A Müller 《Water science and technology》2005,51(9):205-212
Different types of constructed wetlands in a pilot-plant system were fed with identical municipal waste water to compare the sanitisation process in two-stage systems. With combinations of a vertical and a horizontal flow filter an E. coli reduction of 5 log10 with an E. coli influent concentration of 10(7) MPN/100 ml was achieved. Using different filter materials in each stage the total performance of the two-stage system was independent from the sequence of these materials. However, using coarser filter material in the first stage makes the filter less prone to clogging and is thus the preferential option with regard to operational reliability. 相似文献
28.
C Phanuwan S Takizawa K Oguma H Katayama A Yunika S Ohgaki 《Water science and technology》2006,54(3):203-210
Floodwaters in Kampung Melayu village, Jakarta, Indonesia, as well as river water and consumable water (including groundwater and tap water) samples in flooded and non-flooded areas, were quantitatively analysed to assess occurrence of viruses and total coliforms and E. coli as bacterial indicators after flooding event. High numbers of enterovirus, hepatitis A virus, norovirus (G1, G2) and adenovirus were detected at high concentration in floodwaters and waters sampled from Ciliwung River which runs across metropolitan Jakarta and is used widely for agriculture and domestic purposes by poor residents. One out of three groundwater wells in the flooded area was contaminated with all viruses tested while no viruses were found in groundwater samples in non-flooded areas and tap water samples. The results revealed that human enteric viruses, especially hepatitis A virus and adenovirus, were prevalent in Jakarta, Indonesia. This study suggested that flooding posed a higher risk of viral infection to the people through contamination of drinking water sources or direct contact with floodwaters. 相似文献
29.
M A M Maqueda Sergio A Martinez D Narváez Miriam G Rodriguez Ricardo Aguilar Victor M Herrero 《Water science and technology》2006,53(11):135-142
The Mexican petrochemical industry, Morelos S.A. de C.V., is one of the biggest and more important petroleum industries in Mexico and Latin America. It has an activated sludge system to treat its wastewater flow, which is approximately 7,000 m3/d. The wastewater contains volatile organic carbon substances classified as toxics. The old surface aeration system was changed for fine bubble diffusers; however, one major drawback of the new aeration system is that the temperature in the bioreactor has increased due to the compression of the air, which at the compressor exit reaches 85 degrees C. This effect results in the temperature in the bioreactor attaining 32 degrees C during the fall, whereas in the spring and summer, the bioreactor temperature reaches higher values than 40 degrees C. The high temperatures reduce the microorganism activity and cause a higher volatilisation rate of volatile compounds, among other effects, which affect the performance of the biological treatment. This work was performed to obtain a better modelling of the wastewater treatment from the petrochemical industry. The model describes the effect of the temperature on the performance of the biological treatment. The model was obtained from tests that were carried out in laboratory reactors with 14 L capacity, which were operated at different temperatures (from 30 to 45 degrees C), with the same wastewater and conditions as the actual system. 相似文献
30.
J Alemany J Comas C Turon M D Balaguer M Poch M A Puig J Bou 《Water science and technology》2005,51(10):179-186
The identification of adequate wastewater treatment for small communities is a complex problem since it demands a combination of data from different sources, such as aspects of the community and landscape, the receiving environment and the available wastewater treatment technologies. The Catalan Water Agency (Agència Catalana de l'Aigua) considered using an EDSS (Environmental Decision Support System) as a tool to help water managers select the most adequate treatment for the urban wastewater of nearly 3,500 small communities in Catalonia (Spain). From that moment, EDSS was applied to all the river basins in Catalonia. In this paper the authors present the results obtained for the 76 small communities located in one of these river basins: the Fluvia River Basin. The characteristics of the community used in the reasoning process of the EDSS, the list of selected wastewater treatment alternatives, the technical environmental justification for the selected treatments and the reasons for discarding, favouring or disadvantaging them are presented. Finally, some results for the Fluvia River Basin are compared with those obtained in other Catalan river basins with different characteristics in order to evaluate which are the significant features in identifying adequate wastewater treatments. 相似文献