Optimization of silicon solar cell fabrication based on neural network and genetic programming modeling

This study describes techniques for the cascade modeling and the optimization that are required to conduct the simulator-based process optimization of solar cell fabrication. Two modeling approaches, neural networks and genetic programming, are employed to model the crucial relation for the consecutively connected two processes in solar cell fabrication. One model (Model 1) is used to map the five inputs (time, amount of nitrogen and DI water in surface texturing and temperature and time in emitter diffusion) to the two outputs (reflectance and sheet resistance) of the first process. The other model (Model 2) is used to connect the two inputs (reflectance and sheet resistance) to the one output (efficiency) of the second process. After modeling of the two processes, genetic algorithms and particle swarm optimization were applied to search for the optimal recipe. In the first optimization stage, we searched for the optimal reflectance and sheet resistance that can provide the best efficiency in the fabrication process. The optimized reflectance and sheet resistance found by the particle swarm optimization were better than those found by the genetic algorithm. In the second optimization stage, the five input parameters were searched by using the reflectance and sheet resistance values obtained in the first stage. The found five variables such as the texturing time, amount of nitrogen, DI water, diffusion time, and temperature are used as a recipe for the solar cell fabrication. The amount of nitrogen, DI water, and diffusion time in the optimized recipes showed considerable differences according to the modeling approaches. More importantly, repeated applications of particle swarm optimization yielded process conditions with smaller variations, implying greater consistency in recipe generation.     

Partial-thickness tears of the rotator cuff: evaluation and management

The approach to management of a partial-thickness rotator cuff tear is best made with the understanding that this is not a singular condition. Rather, partial tears represent the common outcome of a variety of insults to the rotator cuff. Degenerative changes due to aging, anatomic impingement, and trauma may all be etiologic agents. Overhead athletes may develop tears due to repetitive microtrauma or internal impingement. Outlet radiographs and magnetic resonance imaging are recommended for routine preoperative evaluation. A nonoperative treatment program for rotator cuff strengthening and stretching is appropriate as initial treatment; modification of activities and anti-inflammatory medication are often used as well. Operative management may be considered when nonoperative treatment fails. Arthroscopic evaluation is required to determine the true extent of the cuff lesion. Arthroscopic subacromial decompression is recommended when outlet impingement is present. Rotator cuff debridement or formal cuff repair is dependent on the size of the cuff defect and the age and activity level of the patient. The importance of recognizing the different causes of partial-thickness rotator cuff tears is emphasized in this review of pathogenesis, clinical diagnosis, imaging, and treatment.     

Epitaxial Growth of Large‐Grain NiSe Films by Solid‐State Reaction for High‐Responsivity Photodetector Arrays

Film‐based photodetectors have shown superiority for the fabrication of photodetector arrays, which are desired for integrating photodetectors into sensing and imaging systems, such as image sensors. But they usually possess a low responsivity due to low carrier mobility of the film consisting of nanocrystals. Large‐grain semiconductor films are expected to fabricate superior‐responsivity photodetector arrays. However, the growth of large‐grain semiconductor films, normally with a nonlayer structure, is still challenging. Herein, this study introduces a solid‐state reaction method, in which the growth rate is supposed to be limited by diffusion and reaction rate, for interface‐confined epitaxial growth of nonlayer structured NiSe films with grain size up to micrometer scale on Ni foil. Meanwhile, patterned growth of NiSe films allows the fabrication of NiSe film based photodetector arrays. More importantly, the fabricated photodetector based on as‐grown high‐quality NiSe films shows a responsivity of 150 A W^?1 in contrast to the value of 0.009 A W^?1 from the photodetector based on as‐deposited NiSe film consisting of nanocrystals, indicating a huge responsivity‐enhancement up to four orders of magnitude. It is ascribed to the enhanced charge carrier mobility in as‐grown NiSe films by dramatically decreasing the amount of grain boundary leading to scattering of charge carrier.     

Renal proliferative and phenotypic changes in rats with two-kidney, one-clip Goldblatt hypertension

Previous research in this laboratory has shown that preweaning and postweaning juvenile meadow voles, Microtus pennsylvanicus, can acquire a spatial task, the Morris water-maze task. The present study examined the influence of age of juvenile acquisition ("before weaning" (BW; Day 10 and 15 after birth) and "after weaning" (AW; Day 20 and 25 after birth)) of a spatial task on subsequent re-acquisition of the same hidden-platform spatial water-maze task. This study also compared sex differences and litter sex-ratio effects on reacquisition performance. Fifteen litters of adults were re-tested in the same water maze 6 weeks after being initially tested as juveniles. All analyses were conducted using a covariate that removed the group differences in the original task performance. Adult voles from female-biased litters, that had previously learned the task at an older juvenile age (AW), reacquired the same task faster than adults that had previously learned the task at a younger juvenile age (BW). In the adult BW group there was also a significant litter sex-ratio effect such that voles born into a female-biased litter re-acquired the task more slowly than did voles born into a male-biased litter. There were no significant sex or litter sex-ratio effects on spatial learning in the AW group. These results show that adult meadow voles can require a spatial task more quickly if they initially learned the task at an older juvenile age, suggestive of a period of infantile amnesia. In addition, these results indicate that the litter sex-ratio can affect adult spatial performance, suggesting that the relative amount of androgens in utero may influence the development of sexually-dimorphic spatial ability in adulthood.     

phenanthrene biodegradation in soil slurry systems: Influence of salicylate and triton X-100

The effects of a nonionic surfactant (Triton X-100) and a metabolic inducer (salicylate) were investigated in order to enhance the biodegradation rate of phenanthrene in soil slurry systems. The addition of salicylate reduced the time for the complete degradation of phenanthrene up to about 3 times (12.9 mg/L-d) even at highly concentrated soils of 650 mg/kg. The inducer was beneficial not only by increasing metabolic activity of existing cells, but also by increasing cell mass since it was utilized as an additional carbon source. The fraction of fast growing bacteria in total with salicylate addition was much higher compared to that without salicylate. The addition of Triton X-100 ranging from 0 to 10 g/L increased the apparent solubility of phenanthrene in soil slurry, but significantly inhibited the phenanthrene degradation in both slurry and pure liquid systems without any inhibition to cell growth. The phenanthrene degradation was inhibited much more with increasing the surfactant concentration. The inhibition by surfactant addition might be due to the prevention of bacterial adhesion to phenanthrene sorbed to soil and/or decrease of micellar-phase bioavailability     

A vehicle routing problem solved by using a hybrid genetic algorithm

The main purpose of this study is to find out the best solution of the vehicle routing problem simultaneously considering heterogeneous vehicles, double trips, and multiple depots by using a hybrid genetic algorithm. This study suggested a mathematical programming model with a new numerical formula which presents the amount of delivery and sub-tour elimination. This model gives an optimal solution by using OPL-STUDIO(ILOG CPLEX). This study also suggests a hybrid genetic algorithm (HGA) which considers the improvement of generation for an initial solution, three different heuristic processes, and a float mutation rate for escaping from the local solution in order to find the best solution. The suggested HGA is also compared with the results of a general genetic algorithm and existing problems suggested by Eilon and Fisher. We found better solutions rather than the existing genetic algorithms.     

Therapeutic strategies in acute myocardial infarction. Results of STIM 93 registry

A registry was set up by the national college of cardiologists practicing in general hospitals in February 1993. The data concerned mode of admission, demographic details, initial clinical and haemodynamic evaluation and hospital outcome. Special attention was given to the electrocardiographic changes before and, in patients receiving thrombolytic therapy, after treatment. An analysis of predictive factors for mortality was performed both in the group of patients "revascularised" and in the group treated conventionally. One thousand and twenty three cases from 327 centres were analysed. There were 1292 men and 531 women, with an average age of 67.9 years. The average time interval from onset of symptoms to hospital admission was 5 h 30 min, 56.8% of patients arriving within 6 hours. 36.4% of the population underwent thrombolysis or angioplasty, 75% of patients under 75 years of age admitted before the 5th hours underwent a procedure of myocardial revascularisation. The hospital mortality was 14%, 8.7% in those revascularised and 17% in patients treated conventionally. Factors predictive of mortality were age, female gender, Killip Classes III or IV, systolic blood pressure of less than 100 mmHg, heart rate of more than 100/min and contraindications of thrombolysis. The maximum ST depression, the sum of ST depression, the sum of ST elevation and depression, were also significant predictive factors of a fatal hospital outcome in the whole population group and in patients treated conventionally. In the reperfused group, only the initial sum of ST elevation and depression was predictive of mortality: 120 minutes after the beginning of thrombolysis, the sum of ST elevations and of elevations and depressions was predictive of twice the mortality when the values exceeded 0.6 mv and 1.4 mv respectively.     

Clinical, morphologic and immunophenotypic data based on 10 cases of canine muco-cutaneous epidermotropic T-lymphoma (analogous to Mycosis Funcgo?de). Important of an animal model of spontaneous pathology

Our serie of ten canine cutaneous epitheliotropic T-cell lymphomas (CTCL), is found in old dogs, belonging mainly to the Boxer breed. Site on the mucous membranes (especially buccal), the muco-cutaneous junctions, their clinical expression is polymorphous. Lesions, follow on one after another (erythema, plaques, nodules) and are diversely associated in a given animal, the borders between the different stages often being difficult to establish. Adenopathies noted at the time of the diagnosis or during the course of the condition are accompanied by an involvement of the blood and organs (analogous to Sézary's disease). The progression of the disease can be very rapid in the buccal forms, which are generally aggressive, and in cases of violent, uncontrollable pruritus, which may be disturbing for the owner (with requests for euthanasia). The neoplastic infiltrate is constituted of small lymphocytes with hyperchromatic, convoluted nuclei (incipient stages), then large cells with a "histiocytic" appearance for the nodules. Epitheliotropism, which is maximal for the infiltrated plaque stage, shows up either in the form of a flux of totally epitheliotropic isolated cells (Ketron-Goodman type) or in that of Pautrier abscess-like collections. THe veterinary literature is in agreement that the CTCL cell expresses CD3, but two recent studies are in contradiction as regards its membership of helper or cytotoxic/suppressor populations. For our 10 cases, all the cells of lymphocytic morphology were, without exception, CD3+ and CD45+, irrespective of their situation within the epithelium or the chorion. The CD3+ cells in the epithelium were systematically CD8+, CD4- (confirming P.F. Moore's observations), expressing CD5 in a variable way, and, mostly, the Ki-67 nuclear proliferation Ag. The CD3+ cells of the chorion were exclusively, or mainly, CD8+, and occasionally CD4+. They expressed CD5 in a variable way, and, for a minority, the Ki-67 nuclear proliferation Ag. On the pathogenic level, it may be suggested that a T clone, CD8+, undergoes the "homing" phenomenon within the epithelium, enters the cell cycle, then manifests a tropism towards the chorion, which it infiltrates. Despite some particularities, which may be clinical (serious mucous attacks), cytological (the "histiocytic" appearance of the nodule cells) or immunophenotypic (expression of CD8, similar to what is observed in man in a considerable number of Pagetoid reticulosis), CTCL constitutes an interesting model of spontaneous pathology, and could prove useful in: - identifying various etiological factors (given that the dog, as a close commensal of man, is subject to the same environmental factors).     

Intraoperative radiotherapy in 1997

Codon usage bias of 1,117 Drosophila melanogaster genes, as well as fewer D. pseudoobscura and D. virilis genes, was examined from the perspective of relative abundance of isoaccepting tRNAs and their changes during development. We found that each amino acid contributes about equally and highly significantly to overall codon usage bias, with the exception of Asp which had very low contribution to overall bias. Asp was also the only amino acid that did not show a clear preference for one of its synonymous codons. Synonymous codon usage in Drosophila was consistent with "optimal" codons deduced from the isoaccepting tRNA availability. Interestingly, amino acids whose major isoaccepting tRNAs change during development did not show as strong bias as those with developmentally unchanged tRNA pools. Asp is the only amino acid for which the major isoaccepting tRNAs change between larval and adult stages. We conclude that synonymous codon usage in Drosophila is well explained by tRNA availability and is probably influenced by developmental changes in relative abundance.