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991.
Jung‐Yao Chen Yu‐Cheng Chiu Yen‐Ting Li Chu‐Chen Chueh Wen‐Chang Chen 《Advanced materials (Deerfield Beach, Fla.)》2017,29(33)
Solution‐processable organic–inorganic hybrid perovskite materials with a wealth of exotic semiconducting properties have appeared as the promising front‐runners for next‐generation electronic devices. Further, regarding its well photoresponsibility, various perovskite‐based photosensing devices are prosperously developed in recent years. However, most exploited devices to date only transiently transduce the optical signals into electrical circuits while under illumination, which necessitates using additional converters to further store the output signals for recording the occurrence of light stimulation. Herein, a nonvolatile perovskite‐based floating‐gate photomemory with a multilevel memory behavior is demonstrated, for which a floating gate comprising a polymer matrix impregnated with perovskite nanoparticles is employed. Owing to the well photoresponsibility introduced by the embedded nanoparticles, the device is enabled to access multiple wavelength response and the functionalities of recording power/time‐dependent illumination under no vertical electrical field. Intriguingly, a nonvolatility of photorecording exceeding three months with a high On/Off current ratio over 104 can be achieved. 相似文献
992.
Proposing new statistical distributions which are more flexible than the
existing distributions have become a recent trend in the practice of distribution
theory. Actuaries often search for new and appropriate statistical models to
address data related to financial and risk management problems. In the present
study, an extension of the Lomax distribution is proposed via using the approach
of the weighted T-X family of distributions. The mathematical properties along
with the characterization of the new model via truncated moments are derived.
The model parameters are estimated via a prominent approach called the maximum likelihood estimation method. A brief Monte Carlo simulation study to
assess the performance of the model parameters is conducted. An application to
medical care insurance data is provided to illustrate the potentials of the newly
proposed extension of the Lomax distribution. The comparison of the proposed
model is made with the (i) Two-parameter Lomax distribution, (ii) Three-parameter
models called the half logistic Lomax and exponentiated Lomax distributions, and
(iii) A four-parameter model called the Kumaraswamy Lomax distribution. The
statistical analysis indicates that the proposed model performs better than the competitive models in analyzing data in financial and actuarial sciences. 相似文献
993.
994.
CJ Kim 《Canadian Metallurgical Quarterly》1998,24(7):645-651
BACKGROUND: This study augments a randomized controlled trial to analyze the cost-effectiveness of 2 standardized treatments for major depression relative to each other and to the "usual care" provided by primary care physicians. METHODS: A randomized controlled trial was conducted in which primary care patients meeting DSM-III-R criteria for current major depression were assigned to pharmacotherapy (where nortriptyline hydrochloride was given) or interpersonal psychotherapy provided in a standardized framework or a primary physician's usual care. Two outcome measures, depression-free days and quality-adjusted days, were developed using information on depressive symptoms over time. The costs of care were calculated. Cost-effectiveness ratios comparing the incremental outcomes with the incremental costs for the different treatments were estimated. Sensitivity analyses were performed. RESULTS: In terms of both economic costs and quality-of-life outcomes, patients assigned to the pharmacotherapy group did slightly better than those assigned to interpersonal psychotherapy. Both standardized therapies provided better outcomes than primary physician's usual care, but each consumed more resources. No meaningful cost-offsets were found. The incremental direct cost per additional depression-free day for pharmacotherapy relative to usual care ranges from $12.66 to $16.87 which translates to direct cost per quality-adjusted year gained from $11270 to $19510. CONCLUSIONS: Standardized treatments for depression lead to better outcomes than usual care but also lead to higher costs. However, the estimates of the cost per quality-of-life year gained for standardized pharmacotherapy are comparable with those found for other treatments provided in routine practice. 相似文献
995.
CJ Anderson LA Jones LA Bass EL Sherman DW McCarthy PD Cutler MV Lanahan ME Cristel JS Lewis SW Schwarz 《Canadian Metallurgical Quarterly》1998,39(11):1944-1951
The efficacy of 64Cu [T1/2 = 12.7 hr; beta+ (0.655 MeV; 19%); beta- (0.573 MeV; 40%)] as a radioisotope for radiotherapy has been recently established. Here we demonstrate that 64Cu-1,4,8,11 -tetraazacyclotetradecane-N,N',N",N'-tetraacetic acid (TETA)-octreotide, a somatostatin receptor ligand, inhibits the growth of CA20948 rat pancreatic tumors in Lewis rats at doses that cause minimal toxicity. METHODS: Tumor-bearing rats were administered a single 15 mCi (555 MBq) dose, a fractionated dose of 15 mCi given in 2-3 doses over 2-8 days, or control agents of buffer, unlabeled octreotide or 64Cu-labeled TETA. In certain experiments, blood was removed at times from 4-23 days post-treatment, and a complete blood count along with blood chemistry analyses were obtained. RESULTS: Tumor-growth inhibition was significantly greater in rats injected with a single 15 mCi dose than in rats injected with control agents (p < 0.05). Dose fractionation in two doses, either 1 or 2 days apart, induced significantly increased tumor-growth inhibition compared with rats given a single dose (p < 0.05). The only toxicity observed in treated rats was a decrease in the white blood cell count. This drop was more pronounced in rats treated with a single dose compared with those treated with a fractionated dose. Human absorbed doses of 64Cu-TETA-octreotide to normal organs were estimated from biodistribution data in Lewis rats, and these data indicate that radiotherapy with 64Cu-TETA-octreotide in humans would be feasible. CONCLUSION: Copper-64-TETA-octreotide is a promising radiopharmaceutical for targeted radiotherapy of somatostatin receptor-positive tumors. 相似文献
996.
CJ McDonald JM Overhage PR Dexter L Blevins J Meeks-Johnson JG Suico MC Tucker G Schadow 《Canadian Metallurgical Quarterly》1998,280(15):1325-1329
The rain forest canopy is a seamless web through which arboreal creatures efficiently move to reach the edible fruits without any attention to the individual trees. Individual health care computer systems are rich with patient data, but rather than a canopy linking all the trees in the forest, the data "fruit" come from a diverse forest of individual computer "trees"-laboratory systems, word processing systems, pharmacy systems, and the like. These different sources of patient information are difficult or impossible to reach by individual physicians, especially from their offices. The World Wide Web and other standardization technology provide physicians and their institutions the tools needed for seamless and secure access to their patients' data and to medical information, when and where they need it. We and others have adopted these tools to combine independent sources of clinical data. Physicians who assist in the purchase of clinical information systems should demand products in their practice settings that are Web enabled, use standard coding systems, and communicate with other computer systems via broadly accepted protocols. 相似文献
997.
BACKGROUND: If an observer first learns to recognize an object in a specific orientation, a significant increase in processing time usually occurs when the object is subsequently seen in a different orientation; this phenomenon is called the "misorientation effect." The present study examines how quickly and how accurately human observers discriminate between airport maps that are viewed in orientations other than those in which they were initially learned. METHOD: Participants were trained to discriminate between two navigation maps that were seen in only one orientation; they subsequently were tested with maps and aerial photographs of the same airports that were presented in various orientations. RESULTS AND CONCLUSIONS: There were three principal findings: a) discriminative responses to maps of airports were most rapid when the maps were seen in the same orientation as that in which they were initially learned; b) a significant reduction in reaction time (RT) occurred with repeated presentations of the misoriented stimuli; and c) information learned from navigation maps was not sufficient for all observers to recognize aerial photographs of the same airports. 相似文献
998.
A dipole‐type millimeter‐wave (mm‐wave) antenna with directional radiation characteristics is presented. A radiating patch structure composed of a dipole‐type radiation patch and a rectangular‐shaped parasitic patch are initially investigated to achieve a wider bandwidth. To further improve the operating bandwidth and to realize a directional radiation characteristic, this radiating patch structure is top‐loaded above a conducting cavity‐backed ground structure, which has a low profile (thickness of 3 mm). The measured results show that the proposed mm‐wave antenna can achieve a wide 10‐dB bandwidth of 51.3% (29.6‐50.0 GHz) and stable gain across the desired frequency range. Furthermore, good directional characteristics over the entire mm‐wave frequency band with a compact antenna size of 0.64λ40GHz × 0.91λ40GHz × 0.43λ40GHz are also realized. Hence, it is suitable for many small size wireless mm‐wave systems. 相似文献
999.
M.‐H. Yen S. Chen C.‐Y. Wang H.‐L. Chen Y.‐S. Hsu T.‐C. Liu 《Journal of Computer Assisted Learning》2018,34(5):580-589
This article develops a framework for self‐regulated digital learning, which supports for self‐regulated learning (SRL) in e‐learning systems. The framework emphasizes 8 features: learning plan, records/e‐portfolio and sharing, evaluation, human feedback, machine feedback, visualization of goals/procedures/concepts, scaffolding, and agents. Each feature facilitates or supports one or more SRL skills, including planning, monitoring and evaluating learning, applying appropriate cognitive strategies, and setting standards of products or performance. The implementation in domain‐general and ‐specific systems as illustrated by web‐based inquiry and problem‐solving are discussed. Examples and learning effects are elicited from the literature to demonstrate various designs. Approaches for designing SRL systems, educational implications, and new directions for future research incorporating SRL into digital learning are presented. 相似文献
1000.
Microsystem Technologies - The fuzzy ant colony optimization (FACO) method proposed in this paper minimizes the iterative learning error of the ant colony optimization (ACO) algorithm using fuzzy... 相似文献