Dynamic surface tension measurements of surfactant solutions using the maximum bubble pressure method – limits of applicability

One of the essential differences in the design of bubble pressure tensiometers consists in the geometry of the measuring capillaries. To reach extremely short adsorption times of milliseconds and below, the so-called deadtime of the capillaries must be of the order of some 10 ms. In particular, for concentrated surfactant solutions, such as micellar solutions, short deadtimes are needed to minimize the initial surfactant load of the generated bubbles. A theoretical model is derived and confirmed by experiments performed for a wide range of experimental conditions, mainly in respect to variations in deadtime and bubble volume.     

Local approximations for maximum partial subgraph problem

We deal with MAXH₀-FREE PARTIAL SUBGRAPH. We mainly prove that 3-locally optimum solutions achieve approximation ratio (δ₀+1)/(B+2+ν₀), where B=max_v∈Vd_G(v), δ₀=min_v∈V(H0)d_H0(v) and ν₀=(|V(H₀)|+1)/δ₀. Next, we show that this ratio rises up to 3/(B+1) when H₀=K₃. Finally, we provide hardness results for MAXK₃-FREE PARTIAL SUBGRAPH.     

利用多普勒信息的波达方向最大似然估计方法

为了充分利用信号的时域特性来改善信号波达方向（ＤＯＡ）的估计性能，本文从最大似然估计出发，推导出了有限快拍，低信噪比情况下多普勒信号波达方向的迭代估计计算法，为进一步减小运算量，本文还推导了一种简化算法，本文提出的两种算法对低信噪比，少快拍数下多普勒信号的ＤＯＡ估计性能比不利用时域特性的ＭＬ方法有明显改善，Ｍｏｎｔｅ－Ｃａｒｌｏ实验验证了本文方法的有效性。     

最大熵重建的迭代凸I投影算法

本文探讨了用迭代凸Ｉ投影（ＩｔｅｒａｔｉｖｅＣｏｎｖｅｘＩ－Ｐｒｏｊｅｃｔｉｏｎ，ＩＣＩＰ）算法求解最大熵Ｘ－ＣＴ重建问题．其思路是将这个复杂问题转化为多个简单子问题，然后迭代地求解这种单约束子问题．理论证明，这种算法收敛并能收敛到问题的最大熵解．这种算法形式优美，仿真结果表明算法同时也是有效的．     

Necessary conditions and non-existence results for autonomous nonconvex variational problems

Classical one-dimensional, autonomous Lagrange problems are considered. In absence of any smoothness, convexity or coercivity condition on the energy density, we prove a DuBois-Reymond type necessary condition, expressed as a differential inclusion involving the subdifferential of convex analysis. As a consequence, a non-existence result is obtained.     

Parametric and Non Homogeneous Semi-Markov Process for HIV Control

In AIDS control, physicians have a growing need to use pragmatically useful and interpretable tools in their daily medical taking care of patients. Semi-Markov process seems to be well adapted to model the evolution of HIV-1 infected patients. In this study, we introduce and define a non homogeneous semi-Markov (NHSM) model in continuous time. Then the problem of finding the equations that describe the biological evolution of patient is studied and the interval transition probabilities are computed. A parametric approach is used and the maximum likelihood estimators of the process are given. A Monte Carlo algorithm is presented for realizing non homogeneous semi-Markov trajectories. As results, interval transition probabilities are computed for distinct times and follow-up has an impact on the evolution of patients.      

An improved max-flow-based lower bound for minimizing maximum lateness on identical parallel machines

In this paper, we introduce a new concept of semi-preemptive scheduling and we show how it can be used to derive a maximum-flow-based lower bound for the P|r_j|L_max which dominates the well-known preemptive lower bound. We show that, in some cases, the proposed bound strictly dominates the preemptive one while having the same complexity.     

On the maximum principle for complete second-order elliptic operators in general domains

This paper is concerned with the maximum principle for second-order linear elliptic equations in a wide generality. By means of a geometric condition previously stressed by Berestycki-Nirenberg-Varadhan, Cabré was very able to improve the classical ABP estimate obtaining the maximum principle also in unbounded domains, such as infinite strips and open connected cones with closure different from the whole space. Now we introduce a new geometric condition that extends the result to a more general class of domains including the complements of hypersurfaces, as for instance the cut plane. The methods developed here allow us to deal with complete second-order equations, where the admissible first-order term, forced to be zero in a preceding result with Cafagna, depends on the geometry of the domain.     

InAs／InP_（0．7）Sb_（0．3）热电子晶体管的f_T及f_（max）

用电荷控制及热电子弹道运动模型计算ＩｎＡｓ／ＩｎＰ０．７Ｓｂ０．３热电子晶体管的截止频率ｆＴ及最高振荡频率ｆｍａｘ。结果表明，ｆＴ、ｆｍａｘ分别达到２８０ＧＨｚ及６００ＧＨｚ。并指出，通过生长ＧａＳｂ中间层，ＩｎＡｓ／ＩｎＰ０．７Ｓｂ０．３ＨＥＴ可在ＧａＡｓ衬底上实现单片集成。