The purpose of this thesis is to present a mathematical model in which we describe the theoretical approximation of the elliptic filters. From this theoretical treatment, the transfer function and its magnitude, as well as its poles and zeros, were programmed in Turbo Pascal for AT&T and IBM (PC/XT/AT) personal computers and their compatibles. The program, PC-ELLIP, also calculates the element values for double terminated two-port networks. Source code is included.

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Passive permeation through biological membranes is an important mechanism for transporting molecules and regulating the cellular content. Studying and understanding passive permeation is also extremely relevant to many industrial applications, including drug design and nanotechnology. In vivo membranes typically consist of mixtures of lamellar and nonlamellar lipids. Lamellar lipids are characterised by their tendency to form lamellar bilayer phases, which are predominant in biology. Nonlamellar lipids, when isolated, instead form non-bilayer structures such as inverse hexagonal phases. While mixed lamellar/nonlamellar lipid membranes tend to adopt the ubiquitous bilayer structure, the presence of nonlamellar lipids is known to have profound effects on key membrane properties, such as internal distributions of stress and elastic properties. This dissertation examines permeation through lamellar and nonlamellar lipid membranes by utilising atomistic molecular dynamics simulations in conjunction with two di erent methods, the z-constraint and the z-restraint, in order to obtain transfer free energy profiles, diffusion profiles and permeation coefficients. An assessment of these methods is performed in search for the optimal, with the goal to create an automated, accurate and robust permeation study framework. Part of the dissertation involves the creation of the corresponding software. Furthermore, this work examines the effect of changing the lamellar vs. nonlamellar lipid composition on the passive permeation mechanism of a series of 13 small molecules and drugs. These nonlamellar lipids are known to affect the lateral pressure distribution inside the membranes. This work investigates the hypothesis that the differences in lateral pressure should increase the resistance to permeation. The results indicate that, upon addition of nonlamellar lipids, permeation is hindered for small molecules but is facilitated for the largest. All results are in agreement with previous experimental and computational studies. This work represents an advancement towards the development of more realistic in silico permeability assays, which may have a substantial future impact in the area of rational drug design.

Academic scientific language is characterized by an impersonal and objective style. Due to this and the typical high information density of academic language, this style typically contains a high rate of noun phrases and passive structures. This is also true for the German scientific study Gefühlte Opfer, Illusionen der Vergangenheitsbewältigung by Ulrike Jureit and Christian Schneider. The first aim of this essay was to translate one chapter from the aforementioned book into Swedish and adapt the target language to culturally match a reader who would appreciate a text on German post-war history and sociology. The second aim was to quantify and analyse all occurrences of passive voice and similar structures. More specifically, the following research questions were investigated: How is the passive formed in the source and target language respectively? How often is a corresponding passive used in the translation? How often is a passive sentence translated into an active structure? There are many different ways of expressing the passive in German: the so-called Vorgangspassiv featuring the auxiliary werden, the so-called Zustandspassiv with sein, and finally passive-like constructions. There are corresponding ways to form the passive in Swedish, that is, structures with the auxiliaries bli and vara, but the more common way to express the passive voice is the morphological s-passive. Passive-like constructions can be found in Swedish as well. The most common passive structure in the source text, the werden-passive, was in most cases translated into the typical Swedish s-passive. The sein-passive was more often translated into a similar structure in the target text. All in all, almost a third of the passive voice sentences were translated into active structures. Keywords: translation, passive voice, academic language

Radio frequency (RF) filters are one of the key building blocks in modern microelectronic digital communication systems that use a narrow frequency band with strong interferers nearby. The objective of this thesis is to explore the better DR performance of RF filters using the Q-enhanced LC filter. It takes a divide-and-conquer method by designing 1. A new simple pseudo-differential pair (PDP) for input gm stage. It is the fastest, high-linearity, low-distortion, and wide-range constant-gm design reported to date. This has been applied in the final filter tape-out and has proven to be effective experimentally. 2. A new tunable discrete inductor (TDL) to achieve two-level inductance with the same real estate that can be used to expand the filtering frequency range. This has been verified experimentally. 3. A new tunable discrete capacitor (TDC) to achieve high linearity over wide terminal voltage swing range. This has been verified through simulation. 4. A new systematic way to achieve synchronized gain, center frequency, and filtering Q tuning capability for Q-enhanced LC filters. It has been verified through simulation. In order to verify the concept, a 900 MHz filter is designed and fabricated with National Semiconductor Company (NSC)'s standard 0.18 um digital epi-substrate CMOS technology, and packaged with NSC's LLP-28. The measurement results show that with filter Q of 17 at 845 MHz, the 1 dB compression point is measured to be +4 dBm, IIP3 to be +16 dBm with a peak noise floor of -154 dB/Hz, spurious free dynamic range (SFDR) to be 71 dB. With filter Q of 70 over a 20 MHz BW, the 1 dB compression point is measured to be -9.5 dBm, IIP3 to be +7 dBm with a peak noise floor of -141 dB/Hz, SFDR to be 57 over 20 MHz BW. This filter uses between 56 and 60 mA with a power supply of 1.8 V due to the low-Q (Q~1) of inductor. It is the RF filter with the highest DR in the published literature. The DR can be even higher if inductor Q can be improved as DR is proportional to Q^2.

Recently, plenty of large/public buildings have been completed in Taiwan. For bright indoor environment and comfortable feelings, these buildings often utilized lots of large spaces such as atria. However, it is difficult to maintain tenable conditions within atria and large spaces in case of fire. Therefore, the alert of smoke detectors and the efficiency of smoke control systems are both very important when a fire occurred and people needed to evacuate. In large space buildings, the smoke exhaust fan and smoke storage are major design concepts of the passive smoke management systems in order to maintain tenable conditions in means of egress. In this research, the operation strategies of passive smoke management and fire detection systems in large space buildings will be systematically analyzed. The full-scale hot smoke test can be performed to evaluate the temperature distribution of smoke layer and the smoke descending rate at ABRI large space fire lab in Tainan. In the other hand, the beam detectors can not only detect smoke layer by fire more earlier but show excellent smoke rejection if they can be effectually connected with passive smoke control systems. It is anticipated that through the execution of this research project, the concept developed in this study can be applied to improve the passive smoke management performance of large space buildings in Taiwan.

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Thesis (M. Phil.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 83-97). Also available in print.