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131.
Sangjin Jeong Chan‐Hyun Youn Minho Kang Kyoung‐Seon Min Hyun Ha Hong Hae Geun Kim 《ETRI Journal》2002,24(2):97-108
Optical Border Gateway Protocol (OBGP) is an extension to BGP for Optical Cross Connects (OXCs) to automatically setup multiple direct optical lightpaths between many different autonomous domains. With OBGP, the routing component of a network may be distributed to the edge of the network while the packet classification and forwarding is done in the core. However, it is necessary to analyze the stable convergence functions of OBGP in case of lightpath failures. In this paper, we first describe the architecture of the OBGP model and analyze the potential problems of OBGP, e.g., virtual BGP router convergence behavior in the presence of lightpath failure. We then propose an OBGP convergence model derived from an inter‐AS (Autonomous System) relationship. The evaluation results show that the proposed model can be used for a stable OBGP routing policy and OBGP routing convergence under lightpath failures of the optical Internet. 相似文献
132.
In Hwan Park Yoon Hyun Kim Jae Sang Cha Yeong Min Jang Jin Young Kim 《Wireless Personal Communications》2011,60(3):533-545
In this paper, effects of reader-to-reader interference are investigated for LED identification (LED-ID) system in a multi-reader
environment. The LED-ID readers typically use different channels to avoid collision between readers. However, in-channel collision
usually happens in terms of interrogation range. A reader-to-reader interference scenario is proposed, and nominal interrogation
range of a desired reader is derived from this model. In order to evaluate the LED-ID reader-to-reader interference quantitatively,
an efficient detection scheme is proposed and simulated by employing spreading sequence. The spreading sequence is inserted
between each user’s frame formats. In the receiver, the desired signal is detected by using correlation among inserted spreading
sequences. From simulation results, it is confirmed that the proposed scheme is very effective to enhance reliability of LED-ID
communication systems. 相似文献
133.
Se Hyun Kim Mi Jang Hoichang Yang John E. Anthony Chan Eon Park 《Advanced functional materials》2011,21(12):2198-2207
A chemically coupled polymer layer is introduced onto inorganic oxide dielectrics from a dilute chlorosilane‐terminated polystyrene (PS) solution. As a result of this surface modification, hydrophilic‐oxide dielectrics gain hydrophobic, physicochemically stable properties. On such PS‐coupled SiO2 or AlOx dielectrics, various vacuum‐ and solution‐processable organic semiconductors can develop highly ordered crystalline structures that provide higher field‐effect mobilities (μFETs) than other surface‐modified systems, and negligible hysteresis in organic field‐effect transistors (OFETs). In particular, the use of PS‐coupled AlOx nanodielectrics enables a solution‐processable triethylsilylethynyl anthradithiophene OFET to operate with μFET ~ 1.26 cm2 V?1 s?1 at a gate voltage below –1 V. In addition, a complementary metal‐oxide semiconductor‐like organic inverter with a high voltage gain of approximately 32 was successfully fabricated on a PS‐coupled SiO2 dielectric. 相似文献
134.
This study was carried out to determine optimum conditions of five different factors (beta-cyclodextrin concentration, mixing temperature, mixing time, centrifugal force, and centrifugation time) in reduction of cholesterol in 3.6% fat, homogenized milk by application of beta-cyclodextrin. beta-Cyclodextrin at 0.5 to 1.5% provided 92.2 to 95.3% removal of cholesterol when mixed at 10 degrees C for 10 min. Among other factors, mixing time (5 to 20 min) did not significantly affect cholesterol removal. Removal was enhanced with increasing centrifugal forces up to 166x g (95.9%) but decreased thereafter. Various centrifugation times (5 to 20 min) did not have significant effects. Based on these results, we suggest that the optimum conditions for the process are addition of 1.5% beta-cyclodextrin, mixing temperature of 10 degrees C, 10-min mixing time, and centrifugation at 166x g for 10 min. 相似文献
135.
Hydraulic systems play an important role in modern industry for the reason that hydraulic actuator systems have many advantages over other technologies with electric motors, as they possess high durability and the ability to produce large forces at high speeds. Therefore, the hydraulic actuator has a wide range of application fields such as hydraulic punching, riveting, pressing machines, and molding technology, where controlled forces or pressures with high accuracy and fast response are the most significant demands. Consequently, many hybrid actuator models have been developed for studying how to control forces or pressures with best results.This paper presents a kind of hydraulic load simulator for conducting performance and stability testing related to the force control problem of hydraulic hybrid systems. In the dynamic loading process, perturbation decreases control performance such as stability, frequency response, and loading sensitivity decreasing or bad. In order to improve the control quality of the loading system while eliminating or reducing the disturbance, a grey prediction model combined with a fuzzy PID controller is suggested. Furthermore, fuzzy controllers and a tuning algorithm are used to change the grey step size in order to improve the control quality. The grey prediction compensator can improve the system settle time and overshoot problems. Simulations and experiments on the hydraulic load simulator are carried out to evaluate the effectiveness of the proposed control method when applied to hydraulic systems with various external disturbances encountered in real working conditions. 相似文献
136.
Vanish Kumar Deepak Kukkar Beshare Hashemi Ki‐Hyun Kim Akash Deep 《Advanced functional materials》2019,29(16)
Cancer is the second most common cause of death in the world. The principal limitations thus far encountered in the clinical practice of probing cancer are diverse and include low sensitivity, time consumption, bulkiness, and cost. In this respect, nanomaterial (NM)‐based sensing techniques are recognized as a superior alternative to efficiently resolve such limitations. A better understanding of NM‐based sensing platforms is thus important so that these novel avenues can easily be explored for clinical applications. These platforms have the merits of high sensitivity, high specificity, rapid response, and easy‐to‐read signals. This review offers a comprehensive survey of NM‐based advanced cancer‐sensing techniques and will help the scientific community establish optimum sensing strategies based on an accurate assessment of the interactions between cancer biomarkers and NM‐based platforms. 相似文献
137.
Hyeongdo Choi Yong Jun Kim Jinseob Song Choong Sun Kim Gyu Soup Lee Seongho Kim Jiwon Park Se Hwan Yim Sang Hyun Park Hye Rim Hwang Min‐Hee Hong Pandiyarasan Veluswamy Byung Jin Cho 《Advanced functional materials》2019,29(20)
Fabricating thermoelectric generators (TEGs) using the screen‐printing process has advantages, including mass production, device scalability, and system applicability. However, the thick film formed through the process typically has low film density, and reduced performance, because of the presence of pores in the film created by the vaporization of the resin during high‐temperature annealing. During the soldering process used for thermoelectric module fabrication, the printed solder infiltrates into the screen‐printed electrodes through the micropores in the electrodes, causing cracks of the electrode film and an increase in resistivity. In this paper, an ultraviolet radiation (UV)‐curable process for screen‐printed electrodes is reported. The paste for the electrodes is synthesized by mixing Ag flakes that can be cured at low temperature with a UV resin. Scanning electron microscope images show that the UV‐curing process significantly reduces pores and thereby results in a smooth‐surfaced electrode layer. The film density after crystallization is also enhanced. TEGs composed of 72 couples with UV‐curable Ag electrodes generate a high power density of ≈6.69 mW cm?2 at a temperature difference of 25 °C; the device resistance is ≈0.75 Ω, and the figure of merit of the device is recorded to be 0.57, which is the highest among the printed TEGs. 相似文献
138.
Designing Thin,Ultrastretchable Electronics with Stacked Circuits and Elastomeric Encapsulation Materials 下载免费PDF全文
Renxiao Xu Jung Woo Lee Taisong Pan Siyi Ma Jiayi Wang June Hyun Han Yinji Ma John A. Rogers Yonggang Huang 《Advanced functional materials》2017,27(4)
Many recently developed soft, skin‐like electronics with high performance circuits and low modulus encapsulation materials can accommodate large bending, stretching, and twisting deformations. Their compliant mechanics also allows for intimate, nonintrusive integration to the curvilinear surfaces of soft biological tissues. By introducing a stacked circuit construct, the functional density of these systems can be greatly improved, yet their desirable mechanics may be compromised due to the increased overall thickness. To address this issue, the results presented here establish design guidelines for optimizing the deformable properties of stretchable electronics with stacked circuit layers. The effects of three contributing factors (i.e., the silicone interlayer, the composite encapsulation, and the deformable interconnects) on the stretchability of a multilayer system are explored in detail via combined experimental observation, finite element modeling, and theoretical analysis. Finally, an electronic module with optimized design is demonstrated. This highly deformable system can be repetitively folded, twisted, or stretched without observable influences to its electrical functionality. The ultrasoft, thin nature of the module makes it suitable for conformal biointegration. 相似文献
139.
Hongkyung Lee Xiaodi Ren Chaojiang Niu Lu Yu Mark H. Engelhard Inseong Cho Myung‐Hyun Ryou Hyun Soo Jin Hee‐Tak Kim Jun Liu Wu Xu Ji‐Guang Zhang 《Advanced functional materials》2017,27(45)
Lithium (Li) metal is one of the most promising candidates for the anode in high‐energy‐density batteries. However, Li dendrite growth induces a significant safety concerns in these batteries. Here, a multifunctional separator through coating a thin electronic conductive film on one side of the conventional polymer separator facing the Li anode is proposed for the purpose of Li dendrite suppression and cycling stability improvement. The ultrathin Cu film on one side of the polyethylene support serves as an additional conducting agent to facilitate electrochemical stripping/deposition of Li metal with less accumulation of electrically isolated or “dead” Li. Furthermore, its electrically conductive nature guides the backside plating of Li metal and modulates the Li deposition morphology via dendrite merging. In addition, metallic Cu film coating can also improve thermal stability of the separator and enhance the safety of the batteries. Due to its unique beneficial features, this separator enables stable cycling of Li metal anode with enhanced Coulombic efficiency during extended cycles in Li metal batteries and increases the lifetime of Li metal anode by preventing short‐circuit failures even under extensive Li metal deposition. 相似文献
140.
This study investigates the (de)mobilizing influences of political (dis)agreement in the news and in political discussion on political attitudes and participation in new information environments. Results demonstrate the mediating functions of political ambivalence in that exposure to proattitudinal news reduces ambivalence and thereby promotes political participation, whereas exposure to counter-attitudinal news increases ambivalence and thereby discourages participation. Importantly, the effect of exposure to counter-attitudinal news on ambivalence was moderated by heterogeneous discussion networks on social network sites, such that the combination of exposure to counter-attitudinal news and to heterogeneous discussion networks amplifies ambivalence additively, and thereby augments the tendency toward demobilization. These results are interpreted as suggesting that changing media contexts may lead to complex roles of news and political discussion. 相似文献