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31.
A novel reconfigurable microstrip patch antenna with frequency and polarization diversities is proposed. A U‐slot is incorporated into a square patch, and a PIN diode is utilized to switch the slot on and off, which realizes the frequency diversity characteristic. The polarization diversities among linear polarization (LP), right‐hand circular polarization (RHCP), and left‐hand circular polarization (LHCP) are also obtained by switching three PIN diodes on the slot and the truncating corners of a square patch on and off. The antenna design and experimental results are presented. 相似文献
32.
Modeling molecular interactions in signalling networks is important from various perspectives such as predicting side effects
of drugs, explaining unusual cellular behavior and drug and therapy design. Various formal languages have been proposed for
representing and reasoning about molecular interactions. The interactions are modeled as triggered events in most of the approaches.
The triggering of events is assumed to be immediate: once an interaction is triggered, it should occur immediately. Although
working well for engineering systems, this assumption poses a serious problem in modeling biological systems. Our knowledge
about biological systems is inherently incomplete, thus molecular interactions are constantly elaborated and refined at different
granularity of abstraction. The model of immediate triggers can not consistently deal with this refinement. In this paper
we propose an action language to address this problem. We show that the language allows for refinements of biological knowledge,
although at a higher cost in terms of complexity.
相似文献
33.
Abbass Mohammed Y. Kwon Ki-Chul Kim Nam Abdelwahab Safey A. El-Samie Fathi E. Abd Khalaf Ashraf A. M. 《Artificial Intelligence Review》2021,54(5):3349-3360
Artificial Intelligence Review - Visual object tracking has become one of the most active research topics in computer vision, and it has been applied in several commercial... 相似文献
34.
Jung Nam Bae Jin Young Kim Geon Kim Yong Tae Lee Jae Sang Cha 《Multimedia Tools and Applications》2012,57(2):359-372
Recently, watermarking based data transmission techniques using terrestrial digital TV signal have been proposed since they
are also cost-free and can overcome the limitations of GPS. However, in the previous watermarking based methods, the detection
accuracy is low and additional data rate is too low. Thus, we propose the throughput enhancement method by employing the TZCD-MBOK
watermarking technique in T-DMB system. By applying the proposed scheme to T-DMB, it allows additional data transmission for
disaster broadcasting and improves efficiency of data transmission in shadow region and indoor to mobile environment through
watermarking spread code. From the simulation results, we confirm the proposed watermarking scheme affected on the existing
T-DMB signal. Moreover, it was also confirmed that the system capacity increases as the power of additional watermarking signal
rose. The results of the paper can be applied to wireless multimedia digital broadcasting systems. 相似文献
35.
Namhun Lee Se-Jong Oh Jang-Woo Park Kyung-Rok Nam Kyung-Jun Kang Kyo-Chul Lee Yong-Jin Lee June-Seek Choi Jeong-Ho Seok Jae-Yong Choi 《International journal of molecular sciences》2021,22(5)
Early life stress (ELS) is strongly associated with psychiatric disorders such as anxiety, depression, and schizophrenia in adulthood. To date, biological, behavioral, and structural aspects of ELS have been studied extensively, but their functional effects remain unclear. Here, we examined NeuroPET studies of dopaminergic, glutamatergic, and serotonergic systems in ELS animal models. Maternal separation and restraint stress were used to generate single or complex developmental trauma. Body weights of animals exposed to single trauma were similar to those of control animals; however, animals exposed to complex trauma exhibited loss of body weight when compared to controls. In behavioral tests, the complex developmental trauma group exhibited a decrease in time spent in the open arm of the elevated plus-maze and an increase in immobility time in the forced swim test when compared to control animals. In NeuroPET studies, the complex trauma group displayed a reduction in brain uptake values when compared to single trauma and control groups. Of neurotransmitter systems analyzed, the rate of decrease in brain uptake was the highest in the serotonergic group. Collectively, our results indicate that developmental trauma events induce behavioral deficits, including anxiety- and depressive-like phenotypes and dysfunction in neurotransmitter systems. 相似文献
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38.
Koo Hyun Lee Ki Suk Nam Youl Min Park Pyung Woo Shin Deuk Yong Lee Yo-Seung Song 《Metals and Materials International》2002,8(4):381-385
Plasma nitrocarburized AISI 1020 steels were oxidized for 15, 30 and 60 min to evaluate their corrosion and microstructural properties. After plasma nitrocarburizing for 3 h at 570°C in a gas mixture comprising 85 vol.% N2, 12vol.% H2 and 3 vol.% CH4, the compound layer composed of ɛ-Fe2–3(N,C) and γ’-Fe4(N,C) phases and the diffusion layer above the matrix were observed. The top oxide layer, consisting mainly of magnetite (Fe2O4) and hematite (Fe2O3) phases, forms after post-oxidation treatment at 500°C. However, the oxide layer was severely degraded by spallation as a result of increases in post-oxidizing time. The difference in corrosion resistance should be attributed to the thickness of the top oxide layer, which was governed by post-oxidizing time. 相似文献
39.
Pil-Ryung Cha Ho-Seok Nam Dae-Yeong Jeon Jong-Kyu Yoon 《Metals and Materials International》2002,8(1):119-127
This study presents a simple and robust algorithm for the optimal design of the system with coupled complex transport phenomena:
the transport phenomena comprise fluid flow, heat and mass transfer. The (1+1)-Evolution Strategy method is adopted as the optimization method. In order to analyze the transport phenomena in the complex geometry generated
during the optimization procedure, thefinite volume method with a boundary fitted curvilinear coordinate system is used. To confirm the validity of the present method, the optimal
design for the inner shape of the simplified two-dimensionalSubmerged Entry Nozzle in the continuous slab caster is conducted. It is shown that the resulting design of the nozzle is consistent with the purpose
and constraints of the design. 相似文献
40.
Baik Joon Hyun Yim Sung Dae Nam In-Sik Mok Young Sun Lee Jong-Hwan Cho Byong K. Oh Se H. 《Topics in Catalysis》2004,30(1-4):37-41
Topics in Catalysis - Among the catalysts screened, Cu-ion exchanged ZSM5 zeolite exhibited the highest NO removal activity, particularly at low reaction temperatures below 200 °C,... 相似文献