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We address the problem of estimating blindly a linearly modulated sequence of unknown rate transmitted over an unknown frequency selective channel. We achieve the goal by extending the concept of deconvolution to a cyclo-stationary context and present a generic class of functionals, the minimization of which achieves the equalization. This defines estimates of the symbol rate: by construction, they are insensitive to a lack of excess bandwidth, bestowing a clear advantage on them over the estimates of the literature.  相似文献   
2.
We present in this letter a blind frame synchronization method based on a Maximum A Posteriori probability (MAP) approach. Applied to coded communication systems, this method is based on the calculation of the Log-likelihood Ratios (LLR) of the syndrome obtained according to the parity check matrix of the code. After presenting the proposed method, we compare it to an existing blind synchronization method previously introduced. Simulation results show that the proposed method outperforms the existing one and presents good performance when applied to codes having a sparse parity check matrix such as Low Density Parity Check (LDPC) codes and convolutional codes.  相似文献   
3.

BACKGROUND

Oyster refinement using land‐based pond systems is a new activity in the Dutch oyster sector. It increases the oyster's tissue weight and changes its sensorial properties. However, the response of Dutch consumers towards refined oysters is unknown. The research aim was to gain insight into the importance of oyster quality parameters, drivers for oyster consumption, and acceptance of refined oysters by Dutch consumers, taking into account the information given to them about the product and process.

RESULTS

Taste, texture, and odor are the most important oyster quality characteristics for Dutch consumers. The outcome of questionnaires showed that willingness to buy and pay is influenced by factors such as the oysters' country of origin, cultivation area, and flavor profile. Refinement did not affect willingness to buy and pay. Furthermore Dutch consumers seem to have a preference for the flavor profile of refined oysters. Consumer evaluation showed that refined Pacific cupped oysters were perceived as sweeter compared with non‐refined oysters. When information on the cultivation process was disclosed, overall appreciation of refined oysters by consumers increased.

CONCLUSION

New insights in the importance of oyster quality characteristics for Dutch consumers are generated that can be used in the development of refined Pacific cupped oysters. © 2018 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
4.
We have recently proposed in [1] a blind frame synchronization method based on a Maximum A Posteriori (MAP) approach. In this letter, we study the properties of this method and show that this synchronization technique is well suitable for codes having a sparse parity check matrix, such as Low-Density Parity-Check (LDPC) codes. We also find the probability distributions involved in our synchronization criterion and expand the analytical expression of the probability of false synchronization. Through computer simulations we validate our theoretical results and show that this synchronization technique has excellent performance when applied to LDPC codes. We also show that this method outperforms another approach of blind frame synchronization that computes hard values of the syndrome instead of its Log-Likelihood Ratios (LLR).  相似文献   
5.
Non data-aided SNR estimation of OFDM signals   总被引:1,自引:0,他引:1  
This letter deals with the problem of non data aided (NDA) signal to noise ratio (SNR) estimation of OFDM signals transmitted through unknown multipath fading channel. Most of existing OFDM SNR estimators are based on the knowledge of pilot sequences which is not applicable in some contexts such as cognitive radio for instance. We show that it is possible to take advantage of the periodic redundancy induced by the cyclic prefix to get an accurate NDA SNR estimator. Numerical simulations highlight the benefit of the proposed method compared with the state of the art.  相似文献   
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The antibacterial activities of nitazoxanide and its main metabolite, tizoxanide, were tested against a broad range of bacteria, including anaerobes. Metronidazole, amoxicillin, amoxicillin-clavulanic acid, piperacillin, cefoxitin, imipenem, and clindamycin were used as positive controls. MICs were determined by reference agar dilution methods. The 241 anaerobes were all inhibited by nitazoxanide, with the MICs at which 90% of isolates are inhibited (MIC90S) being between 0.06 and 4 mg/liter with the exception of those for Propionibacterium species, for which the MIC90 was 16 mg/liter. The MIC90s of nitazoxanide were 0.5 mg/liter for the Bacteroides fragilis group (80 strains), 0.06 mg/liter for Clostridium difficile (21 strains), and 0.5 mg/liter for Clostridium perfringens (16 strains). Metronidazole showed a level of activity comparable to that of nitazoxanide except against Bifidobacterium species, against which it was poorly active, and Propionibacterium species, which were resistant to metronidazole. The other antibiotics showed various levels of activity against anaerobes, with imipenem along with nitazoxanide being the most active agents tested. Tizoxanide was less effective than nitazoxanide except against the B. fragilis group, against which its activity was similar to that of nitazoxanide. Under aerobic conditions, nitazoxanide demonstrated poor activity against members of the family Enterobacteriacae and Pseudomonas, Staphylococcus, and Enterococcus species. The same results were obtained when culture was performed under anaerobic conditions with the notable exception of the results against Staphylococcus aureus. The MICs of nitazoxanide were in the range of 2 to 4 mg/liter for 34 clinical isolates of S. aureus, 12 of which were methicillin resistant, while tizoxanide was not effective.  相似文献   
8.
One hundred and seventy patients with Graves' disease underwent thyroidectomy between 1987 and 1994 (10.5% of all thyroidectomies performed in the same period). Female/male ratio was 9/1; mean age 55.2 years and average period between diagnosis and surgical treatment 5.3 years. The average thyroid weight was 230 g (range 90-950 g). Thyroidectomy was subtotal in 110 and total in 60 patients, 5 of which had been previously treated elsewhere from 5 to 33 years before. Malignancy was incidentally found in 2.35% of patients. The complication rate resulted higher in total thyroidectomies than in subtotal procedures (bleeding 0.9% vs 5.4%, transient hypoparathyroidism 4.5% vs 12.7%, recurrent nerve lesion 0.45% vs 2.72%) however the differences were not statistically significant; this probably because both the procedures were carried out with the same technique for parathyroid gland and recurrent nerve safety. The need of repeated surgery increased the risk. In opposition to total thyroidectomy, subtotal thyroidectomy does not doom to complete and permanent replacement therapy (96.4% of hypothyroidism at 2 months, 72.6% at 4 years), but in this series it failed to achieve remission in 2 patients who maintained a mild hyperthyroidism and in one more patient who developed a relapse 4 years later. Serum TSI meaning is not clear, but preoperative positivity suggests a wider resection and postoperative persistence a closer follow-up by functional assessment. In conclusion surgical procedures for Graves' disease range from subtotal to total thyroidectomy but for a safe outcome the choice depends more on the intraoperative troubles of each single case than on theoretic advantages.  相似文献   
9.
将内部IEEE 1149架构与集成在产品中的通信端口链接起来,供外界使用.  相似文献   
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