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91.
Jun Rim Choi Lak Hyun Jang Seong Wook Jung Jin Ho Choi 《Solid-State Circuits, IEEE Journal of》1997,32(3):468-476
A compact 10-b, 288-tap finite impulse response (FIR) filter is designed by adopting structured architecture that employs an optimized partial product tree compression method. The new scheme is based on the addition of equally weighted partial products resulted from 288 multiplications of the filter coefficients and the inputs. The 288 multiplication and 287 addition operations are decomposed to add 1440 partial products and the sign extension operations are manipulated independently to ensure the operation at 72 MHz, the internal clock frequency generated by the integrated phase-locked loop (PLL) clock multiplier. In addition to the optimized transmission gate full adder, modified carry save compression circuits such as 4:2 and 5:5:2 compressors are used to perform decomposed partial product addition. This structured approach enables cascade design that requires more than 288-tap FIR filtering. The completed 288-tap FIR fitter core occupies 5.36×7.29 mm2 of silicon area that consists of 371732 transistors in 0.6-μm triple-metal CMOS technology, and it consumes only 0.8 W of average power at 3.3 V 相似文献
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93.
Baseline concentrations of prolactin (PRL) was determined in the CSF of 28 lobotomized and 28 non-lobotomized patients with chronic schizophrenia. The mean PRL level of the female patients was significantly higher than that of the male patients (p < 0.001). In addition, non-lobotomized patients had significantly higher concentrations of CSF PRL than patients of the lobotomized group (p < 0.05). On the other hand, patients belonging to the latter group exhibited significantly more central as well as cortical brain atrophy than the patients on whom no psychosurgery had been performed (0.05 > p < 0.001). The significance of cerebrospinal PRL as an index of central dopamine metabolism is discussed. 相似文献
94.
A recently proposed circuit P-Q transformation is used to analyze a three-phase controlled-current PWM rectifier. The DC operating point and AC transfer functions are completely determined. Most features of the power converter are clearly interpreted. They are: (1) the output voltage can be controlled from zero to maximum; (2) the system is equivalently an ideal current source in the steady state; (3) the system can be described as linear circuits; and (4) the input power factor can be arbitrarily controlled within a certain control range 相似文献
95.
All parasitics such as switch conduction voltages, conduction resistances, switching times, and ESRs of capacitors are counted in a proposed DC-DC power convertor state-space modeling based method on nonideal switching functions. An equivalent simplified model is derived from the complex circuit with parasitics. The modeling procedure is shown for the buck-boost converter as the general converter among the buck, boost, and buck-boost converters. The pole frequency, DC voltage gain, and efficiency are analyzed and verified by experiments that show good agreement with theory. The procedures for determining the gain margin of the controller, the turn ratio of an isolation transformer, the optimum duty factor, and the switching frequency are given for an example flyback converter 相似文献
96.
Stretchable and Transparent Biointerface Using Cell‐Sheet–Graphene Hybrid for Electrophysiology and Therapy of Skeletal Muscle 下载免费PDF全文
Seok Joo Kim Kyoung Won Cho Hye Rim Cho Liu Wang Sung Young Park Seung Eun Lee Taeghwan Hyeon Nanshu Lu Seung Hong Choi Dae‐Hyeong Kim 《Advanced functional materials》2016,26(19):3207-3217
Implantable electronic devices for recording electrophysiological signals and for stimulating muscles and nerves have been widely used throughout clinical medicine. Mechanical mismatch between conventional rigid biomedical devices and soft curvilinear tissues, however, has frequently resulted in a low signal to noise ratio and/or mechanical fatigue and scarring. Multifunctionality ranging from various sensing modalities to therapeutic functions is another important goal for implantable biomedical devices. Here, a stretchable and transparent medical device using a cell‐sheet–graphene hybrid is reported, which can be implanted to form a high quality biotic/abiotic interface. The hybrid is composed of a sheet of C2C12 myoblasts on buckled, mesh‐patterned graphene electrodes. The graphene electrodes monitor and actuate the C2C12 myoblasts in vitro, serving as a smart cell culture substrate that controls their aligned proliferation and differentiation. This stretchable and transparent cell‐sheet–graphene hybrid can be transplanted onto the target muscle tissue, to record electromyographical signals, and stimulate implanted sites electrically and/or optically in vivo. Additional cellular therapeutic effect of the cell‐sheet–graphene hybrid is obtained by integrated myobalst cell sheets. Any immune responses within implanted muscle tissues are not observed. This multifunctional device provides many new opportunities in the emerging field of soft bioelectronics. 相似文献
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98.
Lee SJ Koo JR Lim DH Park HR Kim YK Ha Y 《Journal of nanoscience and nanotechnology》2011,11(8):7151-7154
We demonstrated efficient and stable white phosphorescent organic light-emitting diodes (OLEDs) with double-emitting layers (D-EMLs), which were comprised of two emissive layers with a hole transport-type host of N,N'-dicarbazolyl-3,5-benzene (mCP) and a electron transport-type host of 2,2',2"-(1,3,5-benzenetryl)tris(1-phenyl)-1H-benzimidazol (TPBi) with blue/orange emitters, respectively. We fabricated two type white devices with single emitting layer (S-EML) and D-EML of orange emitter, maintaining double recombination zone of blue emitter. In addition, the device architecture was developed to confine excitons inside the D-EMLs and to manage triplet excitons by controlling the charge injection. As a result, light-emitting performances of white OLED with D-EMLs were improved and showed the steady CIE coordinates compared to that with S-EML of orange emitter, which demonstrated the maximum luminous efficiency and external quantum efficiency were 21.38 cd/A and 11.09%. It also showed the stable white emission with CIE(x,y) coordinates from (x = 0.36, y = 0.37) at 6 V to (x = 0.33, y = 0.38) at 12 V. 相似文献
99.
Reviews and evaluates psychosocial treatments for attention deficit hyperactivity disorder (ADHD) in children and adolescents according to Task Force Criteria (Lonigan, Elbert, & Johnson, this issue). It is concluded that behavioral parent training and behavioral interventions in the classroom meet criteria for well-established treatments. Cognitive interventions do not meet criteria for well-established or probably efficacious treatments. Issues regarding the evaluative process are discussed and future directions for psychosocial treatment for ADHD are outlined. 相似文献
100.
Stine-Morrow Elizabeth A. L.; Shake Matthew C.; Miles Joseph R.; Noh Soo Rim 《Canadian Metallurgical Quarterly》2006,21(4):790
The authors examined age differences in adults' allocation of effort when reading text for either high levels of recall accuracy or high levels of efficiency. Participants read a series of sentences, making judgments of learning before recall. Older adults showed less sensitivity than the young to the accuracy goal in both reading time allocation and memory performance. Memory accuracy and differential allocation of effort to unlearned items were age equivalent, so age differences in goal adherence were not attributable to metacognitive factors. However, comparison with data from a control reading task without monitoring showed that learning gains among older adults across trial were reduced relative to those of the young by memory monitoring, suggesting that monitoring may be resource consuming for older learners. Age differences in the responsiveness to (information-acquisition) goals could be accounted for, in part, by independent contributions from working memory and memory self-efficacy. Our data suggest that both processing capacity ("what you have") and beliefs ("knowing you can do it") can contribute to individual differences in engaging resources ("what you do") to effectively learn novel content from text. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献