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These findings indicate that slower rates of clearance of viral load and virus-containing immune complexes are associated with subsequent immune activation and contribute to the progression of DHF at this critical stage. Moreover, viral load on the day of defervescence can predict cases of DHF.

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In this article, we demonstrate a semitransparent inverted-type polymer solar cell using a top laminated graphene electrode without damaging the underlying organic photoactive layer. The lamination process involves the simultaneous thermal releasing deposition of the graphene top electrode during thermal annealing of the photoactive layer. The resulting semitransparent polymer solar cell exhibits a promising power conversion efficiency of approximately 76% of that of the standard opaque device using an Ag metal electrode. The asymmetric photovoltaic performances of the semitransparent solar cell while illuminated from two respective sides were further analyzed using optical simulation and photocarrier recombination measurement. The devices consisting of the top laminated transparent graphene electrode enable the feasible roll-to-roll manufacturing of low-cost semitransparent polymer solar cells and can be utilized in new applications such as power-generated windows or multijunction or bifacial photovoltaic devices.

Although the concept of using local surface plasmon resonance based nanoantenna for photodetection well below the semiconductor band edge has been demonstrated previously, the nature of local surface plasmon resonance based devices cannot meet many requirements of photodetection applications. Here we propose the concept of deep-trench/thinmetal (DTTM) active antenna that take advantage of surface plasmon resonance phenomena, three-dimensional cavity effects, and large-area metal/semiconductor junctions to effectively generate and collect hot electrons arising from plasmon decay and, thereby, increase photocurrent. The DTTM-based devices exhibited superior photoelectron conversion ability and high degrees of detection linearity under infrared light of both low and high intensity. Therefore, these DTTM-based devices have the attractive properties of high responsivity, extremely low power consumption, and polarization-insensitive detection over a broad bandwidth, suggesting great potential for use in photodetection and on-chip Si photonics in many applications of telecommunication fields.

Since chemical processes are very complex and some parameters are often unknown or time varying, the derivation of rigorous dynamic model is very difficult and requires extensive engineering manpower. On the other hand, a good dynamic process model is always necessary for the design of the control system. Therefore, system identification becomes an important issue. Recent advances in stochastic or deterministic identification lead to a general conclusion: identify the model for the purpose of control system design (control relevant identification). However, interconnection characteristics of chemical processes impose another constraint: the identification procedure should give as little process upset as possible. In other words, closed-loop identification is preferred for chemical processes.Recently, the relay feedback tests have received a great deal of attention in system identification. Astrom and Hagglund (1984) suggest the use of an ideal (on-off) relay to generate sustained oscillation in closed-loop identification. Subsequently, the important process information, ultimate gain ( K , ) and ultimate frequency (w,), can be found in a straightforward manner. The relay feedback system of an autotuner gains widespread acceptance in pro2ess industries for its reliability and simplicity (Hagglund and Astrom, 1991; and many commercial products for autotuning have appeared in the market since the mid-1980s. Extensions of relay feedback system to monitoring and gain scheduling have also been made (Chiang and Yu, 1993;Lin and Yu, 1993;Luyben and Eskinat, 1994). Moreover, multivariable autotuners were also proposed (Shen and Yu, 1994;Friman and Waller, 1994).The success of the relay feedback autotuner lies on the fact that it identifies one important point on the Nyquist curve: the point at the crossover frequency (ultimate frequency). Luyben (1987) is among the first to employ the relay feedback test for system identification. The autotune variation (ATV) method back calculates system parameters from ultimate gain and ultimate frequency obtained from a relay feedback experiment. Since only process information K , and w, are available, additional process information, such as steady-state gain, should be known apriori in order to fit a typical transfer function (such as a first-, second-or thirdCorrespondence concerning this work should be addressed to C. C. Yu. 1174 April 1996order plus dead time system). In order to alleviate this stringent requirement, Li et al. (1991) and Leva (1994) propose the use of two relay feedback tests to find two points on the Nyquist curve and the least-square method is employed to estimate the parameters of the transfer function. Therefore, the time required for plant test increases as the number of experiments doubled. Then, a question remains: do we really need two relay feedback experiments to identify two points on a Nyquist curve?The biased relay offers some light along this direction. Oldenburger and Boyer (1962) try to eliminate sustained oscillation in some nonlinear elements by ...

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