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41.
We consider pedigree data structured in the form of a directed acyclic graph, and use an encoding scheme, called NodeCodes, for expediting the evaluation of queries on pedigree graph structures. Inbreeding is the quantitative measure of the genetic relationship between two individuals. The inbreeding coefficient is related to the probability that both copies of any given gene are received from the same ancestor. In this paper we discuss the evaluation of the inbreeding coefficient of a given individual using NodeCodes and propose a new encoding scheme, Family NodeCodes, which is further optimized for pedigree graphs. We implemented and tested these approaches on both synthetic and real pedigree data in terms of performance and scalability. Experimental results show that the use of NodeCodes provides a good alternative for queries involving the inbreeding coefficient, with significant improvements over the traditional iterative evaluation methods (up to 10.1 times faster), and Family NodeCodes further improves this to 77.1 times faster while using 91% less space than regular NodeCodes.  相似文献   
42.
This study considers an operation assignment and capacity allocation problem that arises in flexible manufacturing systems. Automated machines are assumed to have scarce time and tool magazine capacities and the tools are available in limited quantities. The aim is to select a subset of operations with maximum total weight. The weight of an operation may represent its profit, processing load, relative priority. Several upper bounding procedures have been taken into account. The results of computational tests have revealed that the proposed upper bounding procedures produce satisfactory solutions in reasonable CPU times. We suggest using some of the bounds when the quality of the solutions is more important than the speed of achieving them and some others when the speed is more important than the quality.  相似文献   
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Generalized selection combining (GSC), in which the best Lc out of L independent diversity channels are linearly combined has been previously proposed and analyzed for Rayleigh fading channels. GSC is a less complex alternative to maximal ratio combining (MRC) that provides a performance gain over traditional selection combining (SC). Both MRC and SC are special cases of CSC, with Lc=L and Lc=1, respectively. We show that CSC also dramatically reduces the impact of switching rate constraints, whereby a selection must be held for the duration of a packet  相似文献   
45.
Photofermentative hydrogen production by immobilized Rhodobacter capsulatus YO3 was carried out in a novel photobioreactor in sequential batch mode under indoor and outdoor conditions. Long-term H2 production was realized in a 1.4 L photobioreactor for 64 days using Rhodobacter capsulatus YO3 immobilized with 4% (w/v) agar on 5 mM sucrose and 4 mM glutamate. The highest hydrogen yield (19 mol H2/mol sucrose) and hydrogen productivity (0.73 mmol H2 L?1 h?1) were achieved indoors on 5 mM sucrose. The effect of initial sucrose concentration (5 mM, 10 mM, and 20 mM) on hydrogen production was also investigated. Sustained hydrogen production was carried out under natural, outdoor conditions as well. For the outdoor experiments, the highest hydrogen productivity and yield were obtained as 0.87 ± 0.06 mmol H2 L?1 h?1 and 6.1 ± 0.2 mol H2/mol sucrose, respectively on 10 mM sucrose. Furthermore, this system prevented sudden pH drops and fluctuations caused by the utilization of sucrose throughout the process. These results demonstrate that a proper immobilization setup can lead to long-term efficient and robust hydrogen production even under naturally varying conditions.  相似文献   
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Effects of modified atmosphere packaging (MAP) on storage stability and quality of precut fresh and aged white cheese were investigated. Fresh or aged white cheese was cut into small cubes and packaged in five different atmospheres [0% O2 + 0% CO+ 100% N2 (MAP1), 10% O+ 0% CO+ 90% N2 (MAP2), 0% O+ 75% CO+ 25% N2 (MAP3), 10% O+ 75% CO+ 15% N2 (MAP4) and aerobic (air)]. Control samples were packaged in brine and vacuum for fresh and aged white cheese, respectively. Changes in gas composition, total plate count, lactococci, lactobacilli, yeast and mould counts, proteolysis, lipolysis, pH, colour, texture and sensory properties were investigated during refrigerated storage. The best packaging treatment for the fresh cheese was MAP3, as it inhibited mould growth and protected the hardness. MAP2 can be recommended for the packaging of the aged cheese, as it decreased lipolysis.  相似文献   
49.
In this study, two‐component free‐standing films were obtained by coating a polycarbonate (PC)‐coated Pt electrode first with polypyrrole (PPy) in an organic medium and then polyaniline (PAn) in an aqueous medium using an electrochemical technique. The amount of PPy and PAn contained in the films was controlled by varying the electrolysis time. The PC/PPy/PAn films were characterized by cyclic voltammetry, conductivity, FTIR and UV–visible spectrophotometry, and thermogravimetric analysis. The resistance change of the films was determined in the temperature range of ?15 to 120 °C and their temperature sensor properties were investigated. © 2002 Society of Chemical Industry  相似文献   
50.
Unlike in subjects with normal renal function, the relationship between hypertension and cardiovascular morbidity and mortality in dialysis patients is still being debated. In order to clarify this issue, we performed 44-hour ambulatory blood pressure measurements (ABPM) during the interdialytic period in a group of 164 hypertensive patients, the blood pressure (BP) control based on conventional antihypertensive strategy previously, on chronic hemodialysis treatment in the Mediterranean region of Turkey. These results were then compared with their echocardiographic data. This is a cross-sectional analysis. The mean ABPM during 44 hours was close to the manually measured predialysis value, but there was a gradual increase in the ABPM values in the interdialytic period. When divided into a group with mild or no left ventricular hypertrophy (LVH) (45 patients) and severe LVH (119 patients), the latter had significantly higher BP levels in all separate periods, while the difference in predialysis BP was not significant. Patients with severe LVH had larger left atrium and left ventricular diameters, and consumed more antihypertensive drugs. Systolic BP during the night before dialysis showed the strongest relation to LVH, but interdialytic weight gain was also independently related to LVH. Yet, 56% of the patients with systolic BP <135 had severe LVH. There is not only an association between BP and presence of LVH, but it is shown that volume expansion is also an important independent determinant of LVH. This may explain the difficulty in identifying hypertension as a cardiac risk factor in these patients.  相似文献   
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