2/spl times/4 optical add-drop module with no difference in propagation length

We developed a micromachined X-type 2/spl times/4 optical add-drop module (OADM) featuring no difference in propagation length. Four pairs of lensed fibers are aligned in "X" position, and four micromirrors are located between the pairs of optical fibers. The OADM was fabricated utilizing a silicon-on-insulator process. Electrostatic comb actuators can be driven up to 90 /spl mu/m to change the light path within 1 ms. The insertion loss and the on-off ratio were less than 3 and 70 dB, respectively. The loss uniformity in every channel was 1.5 dB.     

Study of specific absorption rate (SAR) induced in two child head models and in adult heads using mobile phones

This paper gives a first comparison of specific absorption rate (SAR) induced in a child-sized (CS) head and an adult head using a dual-band mobile phone. In the second study, the visible human head is considered and comparison of SAR induced in a CS or child-like (CL) head and an adult head using a dual-band mobile phone is given. All the peaks of average SAR over a mass of 10 and 1 g in the head and the power budget are determined in the two comparisons using the finite-difference time-domain method. The differences between the results for adult and CS or CL heads are given at 900 and 1800 MHz. No important differences are noted for the peak SAR averaged over 10 g (SAR10 g), between the two adult head models, as well as between the two child head models. The peak SAR10 g in the brain of the CS or CL head is slightly more significant than that for the adult one.     

Coupling efficiency enhancement in organic light-emitting devices using microlens array-theory and experiment

Microlens arrays are introduced on glass substrates to improve the out-coupling efficiency of organic light-emitting devices (OLEDs). The microlenses suppress waveguiding loss in the substrate. A theoretical model, based on electromagnetic wave propagation and geometric ray tracing, is developed to simulate the enhancement effects and optimize the structure parameters of the lens pattern. A simple soft-lithography approach is employed to fabricate the microlens array on glass substrates. With the use of an optimized lens pattern, an increase of over 85% in the coupling efficiency of the OLED is expected theoretically. An increase of 70% in the coupling efficiency is achieved experimentally, without detrimental effect to the electrical performance of the OLED.     

玻璃衬底上MIUC Poly-Si TFT显示驱动电路

以高性能的金属诱导单一方向横向晶化多晶硅薄膜晶体管(MIUC poly-Si TFT)为基础,研制出性能能满足AM-LCD和AM-OLED要求、版图和象素尺寸适配、制备工艺和象素电路兼容的多晶硅TFT行扫描和列驱动电路.该行扫描电路工作电压为3.5-10V;当工作电压为5V、负载电容为22pf时,下降沿约为150ns,上升沿约为205ns,最高工作频率在1MHz以上;列驱动电路工作电压为3.5-8V;当工作电压为5V、负载电容为22pf时,上升沿约为200ns,信号衰减率为15%(64μs扫描周期),最高工作频率达到4MHz.将该MIUC poly-Si TFT多晶硅行扫描、列驱动电路和有源选址电路集成到同一基板上,制备出象素数为80×RGB×60、动态显示效果良好的全集成型LCD屏样品.     

一种新的基于序列蒙特卡罗方法的符号检测器

在衰落信道下检测传输符号是序列蒙特卡罗方法在通信领域中的一个重要应用.由于在序列蒙特卡罗方法中重要函数的选择直接会影响系统性能,针对这一问题,提出了一种新的混合重要函数,较大幅度提高了衰落信道下传输符号的检测水平,仿真结果也证实了这种新检测器的有效性.     

The oral glucose minimal model: estimation of insulin sensitivity from a meal test

Recently, a new approach has been proposed to estimate insulin sensitivity (S(I)) from an oral glucose tolerance test or a meal using an "integral equation". Here, we improve on the "integral equation" by resorting to a "differential equation" approach. The classic glucose kinetics minimal model was used with the addition of a parametric model for the rate of appearance into plasma of oral glucose (Ra). Three behavioral models of Ra were proposed: piecewise-linear (P), spline (S) and dynamic (D). All three models performed satisfactorily allowing a precise estimation of S(I) and a plausible reconstruction of Ra. Mean S(I) estimates were virtually identical: S(I)P = 6.81 +/- 0.87 (SE); S(I)S = 6.53 +/- 0.80; and S(I)D = 6.62 +/- 0.79. S(I) strongly correlated with the integral-equation index (I) S(I)I: r = 0.99, p < 0.01 for models D and S, and r 0.97, p < 0.01 for P. Also, SI compared well with insulin sensitivity estimated from intravenous glucose tolerance test in the same subjects (r = 0.75, p < 0.01; r = 0.71, p < 0.01; r = 0.73, p < 0.01, respectively, for P, S, and D models versus s(I)IVGTT). Finally, the novel approach allows estimation of SI from a shorter test (120 min): model P yielded S(I)R = 7.16 +/- 1.0 (R for reduced) which correlated very well with S(I)P and S(I)I (respectively, r = 0.94, p < 0.01; r = 0.95, p < 0.01) and still satisfactorily with S(I)IVGTT (r = 0.77, p < 0.01).     

探测波导全息光栅傅里叶变换光谱的新方法

提出一种利用波导全息光栅分光元件 ,通过测量波导光栅附近区干涉条纹 ,经快速傅里叶变换达到测量光谱的新方法。讨论了波长测量范围和光谱分辨率。给出了在设计波导光栅、确定探测器时应该考虑的几个问题。对系统测量误差进行了分析。该光谱探测方法具有光谱分辨率高、波长范围宽和结构简单等优点。     

未来信息战中制网权的研究

针对未来信息战中制网权的争夺进行了研究。介绍了未来信息战的主要内容，指出了制网权是未来信息战获胜的关键环节，并对争夺制网权的两大关键要素—网络攻击和网络防护进行了详细的分析．提出取得未来信息战胜利必须采取攻防结合的方法。     

用于纳米精度大范围位移测量的半导体激光干涉仪

本文在作者提出的光频光热调制半导体激光正弦相位调制干涉仪的基础上,提出了一种扩大其测量范围的方法,使得在保持纳米精度的前提下,测量范围由半个波长扩大为125.56μm,并讨论了进一步扩大测量范围的可能性.本方法得到了模拟计算和实验结果的很好验证.     

Design and Validation of an Efficient Authentication Scheme with Anonymity for Roaming Service in Global Mobility Networks

Designing a user authentication protocol with anonymity for the global mobility network (GLOMONET) is a difficult task because wireless networks are susceptible to attacks and each mobile user has limited power, processing and storage resources. In this paper, a secure and lightweight user authentication protocol with anonymity for roaming service in the GLOMONET is proposed. Compared with other related approaches, our proposal has many advantages. Firstly, it uses low-cost functions such as one-way hash functions and exclusive-OR operations to achieve security goals. Having this feature, it is more suitable for battery-powered mobile devices. Secondly, it uses nonces instead of timestamps to avoid the clock synchronization problem. Therefore, an additional clock synchronization mechanism is not needed. Thirdly, it only requires four message exchanges between the user, foreign agent and home agent. Further, the security properties of our protocol are formally validated by a model checking tool called AVISPA. We also demonstrate that this protocol enjoys important security attributes including prevention of various attacks, single registration, user anonymity, no password table, and high efficiency in password authentication. Security and performance analyses show that compared with other related authentication schemes, the proposed scheme is more secure and efficient.