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81.
A synthetic human V(L) phage display library, created by the randomization of all complementarity-determining regions (CDRs) in a V(L) scaffold, was panned against three test antigens to determine the propensity of the library to yield non-aggregating binders. A total of 22 binders were isolated against the test antigens and the majority (20) were monomeric. Thus, human V(L) repertoires provide an efficient source of non-aggregating binders and represent an attractive alternative to human V(H) repertoires, which are notorious for containing high proportions of aggregating species. Moreover, the solubility of V(L)s, in contrast to V(H)s, appears much less CDR dependent.  相似文献   
82.
In view of the intermittency and uncertainty associated with both the electricity production sector of restructured power system and their competitive markets, it is necessary to develop an appropriate risk managing scheme. So that it is desirable to trade-off between optimum utilization of intermittent generation resources (i.e. renewable energy resources), uncertain market prices and related risks in order to maximize participants' benefits and minimize the corresponding risks in the multi-product market environment. The main goal of this paper is to investigate risk management by introducing a novel multi-risk index to quantify expected downside risk (EDR) which is caused by both the wind power and market price uncertainties. Value-at-Risk (VaR) method is used to assess the mentioned risk issue by the proposed weighted EDR, so that an optimal trade-off between the profit and risk is made for the system operations. Also, the roulette wheel mechanism is employed for random market price scenario generation wherein the stochastic procedure is converted into its respective deterministic equivalents. Moreover, the autoregressive integrated moving average (ARIMA) model is employed to characterize the stochastic wind farm (WF) generation by predetermined mean level and standard deviation of wind behavior as well as temporal correlation. The problem is formulated as a mixed-integer stochastic framework for a hydro-wind power system scheduling and tested on a generation company (GENCO).  相似文献   
83.
All-optical flip-flop based on nonlinear effects in fiber Bragg gratings   总被引:1,自引:0,他引:1  
We demonstrate a novel design for a passive all-optical R-S flip-flop with separate set-rest ports based on nonlinearity in the fiber Bragg gratings (FBGs). The spectrum of FBGs in the presence of the Kerr effect is investigated, and cw and transient characteristics of nonlinear-induced bistability of the passive distributed feedback structures are studied by numerical solving of coupled-mode equations. It is shown that a pulse with a pulsewidth of 0.15 ns can switch the state of the flip-flop.  相似文献   
84.
This paper presents a proposed rating model that incorporates the fatigue damaging effects of overloads. This is achieved by introducing a “fatigue index” in the rating equation. The index, which appears in the form of a correction factor in the rating equation, is intended as a means to reduce the rating value computed for a bridge in cases where the damage from overloads is expected to be significant. The use of this index by itself does not impose any upper limit on the total number of overloads that may annually be permitted on a bridge. However, because the use of the index will result in a lower rating value than those from current equations, it is expected that a certain number of overloads will ultimately be disallowed. This provides for a built-in mechanism that will eventually result in lower fatigue damage to highway bridges resulting from overloads. In developing the model, typical records of overloads were acquired and used in bridge structural analyses to determine the damaging effect of overloads. The study on five bridges showed that fatigue damage from overloads can use up about 3.5% of fatigue life over a 25-year period if the overload occurrences remain at the current level. The use of the proposed index is in line with this amount of fatigue damage. This percentage is rather low and may not, in fact, be critical for most bridges over a 25-year period. However for older bridges, this percentage of fatigue life consumption may become important. Many such bridges were designed for a lower gross truck weight than what is used today for bridge design. Some of these bridges are located along feeder ramps and must carry loads in excess of 356 kN (80 kip) in an overload situation. For this group of bridges, it may be important to consider imposing a limit on the amount of fatigue damage resulting from frequent overloads. However, additional studies on a larger pool of bridges will be needed to establish a baseline for a maximum percentage fatigue life that can be used for overload permits.  相似文献   
85.
In this study, hydrolytic degradation of silk fibroin (SF) in Phosphate buffer saline (PBS) after 12 weeks incubation was investigated. Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and X‐ray diffraction (XRD) patterns have confirmed the transition from crystalline β‐sheet to random coil in treated SF. A decrease in adhesion force and surface Young's modulus were observed using atomic force microscopy (AFM). Structural changes were further confirmed using scanning electron microscopy (SEM). Biocompatibility and alkaline phosphatase production of osteoblast cells were decreased significantly in treated SF scaffold. Moreover, a significant decrease in mRNA level of collagen type I and osteopontin compared with fresh SF scaffold was observed. Finally, structural and biological characteristics of SF scaffold could alter in PBS. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 39980.  相似文献   
86.
Confidential authenticated broadcast/multi cast over lossy channels is an important and challenging problem. Applications include the continuous confidential authentication of radio and TV internet broadcast/multicast data distribution by satellite and critical data broadcast in critical tasks (e.g. sensor network for military tasks). Main challenges are authenticity, confidentiality, loss-tolerance, efficiency. Asymmetric cryptography approaches have high security but are expensive in computation and communication. In this paper we propose and prototype a novel loss-tolerance mechanism for lossy channels ensuring authenticity, confidentiality, DoS resistance, efficiency and simplicity. Most applications in practice do not need ideal and perfect real-time task and a minor delay around some seconds is completely acceptable, except a few applications such as safety beacons in VANET. In many applications, such as updating code memory of MANET, delay around some minutes is acceptable, too. Hence, our aim is to provide a robust and dependable loss-tolerant secure broadcast stream at cost of delayed-verification. As an experimental implementation we prototype our proposal in a wireless sensor networks to show its efficiency.  相似文献   
87.
The seismic design requirements used in the United States are based on the recommendations of the American Association of State Highway and Transportation Officials. These requirements are primarily based on the importance of the structure, the level of deformation imposed on the structure, soil conditions, and the ductility of structural members, especially piers and supports. In the performance-based design approach, the design is primarily focused on meeting a performance objective, which is in line with a desired level of service. Currently, the effort toward implementing the performance-based design approach in buildings is under way in the United States. The seismic performance criteria for buildings have been established and reported by various organizations. It seems that at least three levels of performance, ranging from “fully operational” to “near collapse” can be used to meet the postearthquake conditions, safety, usage, and occupancy for the varous levels of service expected from all types of structures. In this paper a critical evaluation of these performance criteria and their relevance to highway bridge design, in conjunction with the current design practice, is discussed. Various types of designs such as those based on strength, deformation, nonlinear behavior, and energy, which can be used to meet the specified performance levels in seismic design of highway bridges, are also discussed in the paper. Examples of real applications of the method in highway bridges are reviewed. Furthermore, the procedure by which the performance-based method has been implemented in these example cases is described and discussed in the paper.  相似文献   
88.
This study examined the effects of abilities as a young adult, an engaged lifestyle, personality, age, and health on continuity and change in intellectual abilities from early to late adulthood. A battery of measures, including a verbal and nonverbal intelligence test, was given to 326 Canadian army veterans. Archival data provided World War Two enlistment scores on the same intelligence test for this sample. Results indicated relative stability of intellectual scores across 40 years, with increases in vocabulary and decreases in arithmetic, verbal analogies, and nonverbal skills. Young adult intelligence was the most important determinant of older adult performance. Predictors for verbal intelligence were consistent with an engagement model of intellectual maintenance but also indicated the importance of introversion–extraversion and age. Nonverbal intelligence in late life was predicted by young adult nonverbal scores, age, health, and introversion–extraversion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
In this article, we use the results of finite-element analysis (FEA) of temperature distribution, deformation, and stress to provide a full three-dimensional simulation of a dynamically stable cavity by propagating wavefront into hot, thermally deformed Yb:YAG/YAG thin-disk laser, using the fast Fourier transform (FFT) split-step beam propagation method (BPM). The wave optics computation therefore delivers realistic results for important features of a laser-like intensity, phase profile, and resonator eigenvalues and higher order-eigenmodes of the laser beam.  相似文献   
90.
In this paper a method to calculate the viscosity of supercritical CO2 is introduced. A rolling body viscometer equipped with a gas booster was used. Based on new experimental and available data, a new correlation is developed. The proposed correlation is valid in temperature range from 310 K to 900 K. Moreover, the model predictions are acceptable in pressures between 7.5 and 101.4 MPa. The model superiority over other conventional methods has been demonstrated.  相似文献   
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