How to write a passable technical paper

In my job I see many students who have not learned to write a technical paper. When they do competent work, I want them to be able to write passable reports. This article is for them. There are well established principles for citing the relevant work of others; for not copying things without giving credit; for not stealing. If a reader feels you have copied anything, a figure, even a phrase, from elsewhere without citing its source, then you are guilty of plagiarism in the eyes of that reader. Committing plagiarism is so bad that I cannot do justice to it here. So I merely say: never do it. On, then, to writing your own honest and original material. Art requires talent. In contrast, through discipline and persistence alone, you can learn how to differentiate functions and ride bicycles. Similarly, you can write a passable technical paper. You just have to realize that your job does not end with research. Writing a passable paper involves extra work.

Redundancy resolution using tractrix -- Simulations and Experiments

Hyper-redundant robots are characterized by the presence of a large number of actuated joints, many more than the number required to perform a given task. These robots have been proposed and used for many applications involving avoiding obstacles or, in general, to provide enhanced dexterity in performing tasks. Making effective use of the extra degrees of freedom or resolution of redundancy has been an extensive topic of research and several methods have been proposed in literature. In this paper, we compare three known methods and show that an algorithm based on a classical curve called the tractrix leads to a more 'natural' motion of the hyper-redundant robot, with the displacements diminishing from the end-effector to the fixed base. In addition, since the actuators nearer the base 'see' a greater inertia due to the links farther away, smaller motion of the actuators nearer the base results in better motion of the end-effector as compared to other two approaches. We present simulation and experimental results performed on a prototype eight link planar hyper-redundant manipulator.

A Novel, Balanced, and Energy-Efficient Training Method for Receive Antenna Selection

In receive antenna selection (AS), only signals from a subset of the antennas are processed at any time by the limited number of radio frequency (RF) chains available at the receiver. Hence, the transmitter needs to send pilots multiple times to enable the receiver to estimate the channel state of all the antennas and select the best subset. Conventionally, the sensitivity of coherent reception to channel estimation errors has been tackled by boosting the energy allocated to all pilots to ensure accurate channel estimates for all antennas. Energy for pilots received by unselected antennas is mostly wasted, especially since the selection process is robust to estimation errors. In this paper, we propose a novel training method uniquely tailored for AS that transmits one extra pilot symbol that generates accurate channel estimates for the antenna subset that actually receives data. Consequently, the transmitter can selectively boost the energy allocated to the extra pilot. We derive closed-form expressions for the proposed scheme's symbol error probability for MPSK and MQAM, and optimize the energy allocated to pilot and data symbols. Through an insightful asymptotic analysis, we show that the optimal solution achieves full diversity and is better than the conventional method.

Signal subspace approach in localization of sound source in shallow water

A new algorithm based on signal subspace approach is proposed for localizing a sound source in shallow water. In the first instance we assumed an ideal channel with plane parallel boundaries and known reflection properties. The sound source is assumed to emit a broadband stationary stochastic signal. The algorithm takes into account the spatial distribution of all images and reflection characteristics of the sea bottom. It is shown that both range and depth of a source can be measured accurately with the help of a vertical array of sensors. For good results the number of sensors should be greater than the number of significant images; however, localization is possible even with a smaller array but at the cost of higher side lobes. Next, we allowed the channel to be stochastically perturbed; this resulted in random phase errors in the reflection coefficients. The most singular effect of the phase errors is to introduce into the spectral matrix an extra term which may be looked upon as a signal generated coloured noise. It is shown through computer simulations that the signal peak height is reduced considerably as a consequence of random phase errors.

Doing marriage and parenthood: The division of household labour across two life course events

The current study is a longitudinal investigation into changes in the division of household labour across transitions to marriage and parenthood in the UK. Previous research has noted a more traditional division of household labour, with women performing the majority of housework, amongst spouses and couples with children. However, the bulk of this work has been cross-sectional in nature. The few longitudinal studies that have been carried out have been rather ambiguous about the effect of marriage and parenthood on the division of housework. Theoretically, this study draws on gender construction theory. The key premise of this theory is that gender is something that is performed and created in interaction, and, as a result, something fluid and flexible rather than fixed and stable. The idea that couples 'do gender' through housework has been a major theoretical breakthrough. Gender-neutral explanations of the division of household labour, positing rational acting individuals, have failed to explicate why women continue to perform an unequal share of housework, regardless of socioeconomic status. Contrastingly, gender construction theory situates gender as the key process in dividing household labour. By performing and avoiding certain housework chores, couples fulfill social norms of what it means to be a man and a woman although, given the emphasis on human agency in producing and contesting gender, couples are able to negotiate alternative gender roles which, in turn, feed back into the structure of social norms in an ever-changing societal landscape. This study adds extra depth to the doing gender approach by testing whether or not couples negotiate specific conjugal and parent roles in terms of the division of household labour. Both transitions hypothesise a more traditional division of household labour. Data comes from the British Household Panel Survey, a large, nationally representative quantitative survey that has been carried out annually since 1991. Here, data tracks the same 776 couples at two separate time points - 1996 and 2005. OLS regression is used to test whether or not transitions to marriage and parenthood have a significant impact on the division of household labour whilst controlling for host of relevant socio-economic factors. Results indicate that marriage has no significant effect on how couples partition housework. Those couples making the transition from cohabitation to marriage do not show significant changes in housework arrangements from those couples who remain cohabiting in both waves. On the other hand, becoming parents does lead to a more traditional division of household labour whilst controlling for socio-economic factors which accompany the move to parenthood. There is then some evidence that couples use the site of household labour to 'do parenthood' and generate identities which both use and inform socially prescribed notions of what it means to be a mother and a father. Support for socio-economic explanations of the division of household labour was mixed although it remains clear that they, alone, cannot explain how households divide housework.

Ühis- ning erijooni Soome ja Eesti Kaitseliitude puhkpillimuusikas aastatel 1925-1934.

This study focuses on the similarities and differences between the Estonian Defence League and the Finnish Civil Guard brass bands during the period 1925-1934. By 1934 this paramilitary volunteer state defence organisation had reached stability in its development, such that social, cultural and patriotic education of the people - with the help of brass band music among other means- had acquired a significant role, in addition to prioritised military and sports activities. The study begins with introductory paragraphs I and II, which describes the founding of the organisations, their participation in the Wars of Independence and their subsequent peace time activities as well as their representation in the media at the time. The thesis also briefly introduces military music in Finland and Estonia, as well as describes the influence of military music on the Defence League brass bands. The period under review includes the global economic crisis, which undoubtedly concerned the Defence League/Civil Guard and the Lapua and War of Independence movements, which greatly affected the apolitical principles of the organisations. The main emphasis of the thesis is the Defence League/Civil Guard brass band`s musical activities in two counties - Etelä-Pohjanmaa and Pärnumaa, while also including a general overview of the Estonian Defence League brass bands´ activities. One of the most important benefits of the thesis is its introduction of the brass band repertoire in use at the time, which was played by both professional and as well as amateur orchestras the latter of which also included the brass bands of the Defence League/Civil Guard and the Fire Services. Brass band music held a secondary, yet significant position in the Defence League/Civil Guard, where the orchestra as a musical grouping was obliged to perform not only at inner-organisational and national celebrations but also at any event requiring brass band music, such as song festivals, singing days, and other local cultural events. The professional preparation of the band conductors at the beginning of the period under review was not well specialised, but the training of the Defence League/Civil Defence brass band conductors was carried out regularly in both republic according to the opportunities and dedicated training programmes available. The musicians of the Defence League/Civil Defence brass bands were at the same time members of the military organisations as well as amateur musicians, which placed upon them extra demands - they were under close public supervision in all situations. Based on the principle of chronology it appeared that both Finnish and Estonian respective organisations´ brass bands used the gradually improving economic situation for purchasing musical instruments, obtaining repertoire and training musicians/conductors. Despite the fact that brass band music in the Defence League/Civil Guard was considered an amateur activity and a hobby, the more far-reaching objective of the organisation was to resemble the Defence Forces´ orchestras as closely as possible in all aspects. The Defence League/Civil Guard brass band music definitely had a significant influence on forming, developing and enriching music life in both republics. The reviewed nine-year period introduced the musical activities of the Defence League/Civil Guard against the background of the everyday life of the organisation and the need for brass band music and its continuity in the voluntary state defence institutions of both republics.

The Transcriptional Regulation of Retrotransposon BARE

The purpose of this research project was to understand the steps of the retrotransposon BARE (BArley REtrotransposon) life cycle, from regulation of transcription to Virus-Like Particle (VLP) formation and ultimate integration back into the genome. Our study concentrates mainly on BARE1 transcriptional regulation because transcription is the crucial first step in the retrotransposon life cycle. The BARE element is a Class I LTR (Long Terminal Repeat) retrotransposon belonging to the Copia superfamily and was originally isolated in our research group. The LTR retrotransposons are transcribed from promoters in the LTRs and encode proteins for packaging of their transcripts, the reverse transcription of the transcripts into cDNA, and integration of the cDNA back into the genome. BARE1 is translated as a single polyprotein and cleaved into the capsid protein (GAG), integrase (IN), and reverse transcriptase-RNaseH (RT-RH) by the integral aspartic proteinase (AP). The BARE retrotransposon family comprises more than 104 copies in the barley (Hordeum vulgare) genome. The element is bound by long terminal repeats (LTRs, 1829 bp) containing promoters required for replication, signals for RNA processing, and motifs necessary for the integration of the cDNA. Members of the BARE1 subfamily are transcribed, translated, and form virus-like particles. Several basic questions concerning transcription are explored in the thesis: BARE1 transcription control, promoter choice in different barley tissues, start and termination sites for BARE transcripts, and BARE1 transcript polyadenylation (I). Polyadenylation is an important step during mRNA maturation, and determines its stability and translatability among other characteristics. Our work has found a novel way used by BARE1 to make extra GAG protein, which is critical for VLP formation. The discovery that BARE1 uses one RNA population for protein synthesis and another RNA population for making cDNA has established the most important step of the BARE1 life cycle (III). The relationship between BARE1 and BARE2 has been investigated. Besides BARE, we have examined the retrotransposon Cassandra (II), which uses a very different transcriptional mechanism and a fully parasitic life cycle. In general, this work is focused on BARE1 promoter activity, transcriptional regulation including differential promoter usage and RNA pools, extra GAG protein production and VLP formation. The results of this study give new insights into transcription regulation of LTR retrotransposons.

Effect of coordinated ions on structure and flexiblity of parallel G-quandruplexes: a molecular dynamics study

Single tract guanine residues can associate to form stable parallel quadruplex structures in the presence of certain cations. Nanosecond scale molecular dynamics simulations have been performed on fully solvated fibre model of parallel d(G7) quadruplex structures with Na+ or K+ ions coordinated in the cavity formed by the 06 atoms of the guanine bases. The AMBER 4.1 force field and Particle Mesh Ewald technique for electrostatic interactions have been used in all simulations. These quadruplex structures are stable during the simulation, with the middle four base tetrads showing root mean square deviation values between 0.5 to 0.8 A from the initial structure as well the high resolution crystal structure. Even in the absence of any coordinated ion in the initial structure, the G-quadruplex structure remains intact throughout the simulation. During the 1.1 ns MD simulation, one Na+ counter ion from the solvent as well as several water molecules enter the central cavity to occupy the empty coordination sites within the parallel quadruplex and help stabilize the structure. Hydrogen bonding pattern depends on the nature of the coordinated ion, with the G-tetrad undergoing local structural variation to accommodate cations of different sizes. In the absence of any coordinated ion, due to strong mutual repulsion, 06 atoms within G-tetrad are forced farther apart from each other, which leads to a considerably different hydrogen bonding scheme within the G-tetrads and very favourable interaction energy between the guanine bases constituting a G-tetrad. However, a coordinated ion between G-tetrads provides extra stacking energy for the G-tetrads and makes the quadruplex structure more rigid. Na+ ions, within the quadruplex cavity, are more mobile than coordinated K+ ions. A number of hydrogen bonded water molecules are observed within the grooves of all quadruplex structures

Study of stress Relief Patterns In Diamond-Like Carbon-Films

An optical microscopy study of stress relief patterns in diamondlike carbon films is presented. Interesting stress relief patterns are observed which include the well known sinusoidal type, branching pattern and string of beads pattern. The last one is shown to relieve stresses under marginal conditions. Two new stress relief patterns are noted in the present study. One of them is of a sinusoidal shape with two extra branches at every peak position. The distribution of different stress relief forms from the outer edge of the films towards the interior is markedly dependent on film thickness. Our new patterns support the approach in which the stress relief forms have been analysed earlier using the theory of plate buckling.

Lenient Execution and Concurrent Execution of Re-entrant Routines: Efficient Implementation in Data Flow Systems

Implementation details of efficient schemes for lenient execution and concurrent execution of re-entrant routines in a data flow model have been discussed in this paper. The proposed schemes require no extra hardware support and utilise the existing hardware resources such as the Matching Unit and Memory Network Interface, effectively to achieve the above mentioned goals.

Euclideanization, topological theories, higher dimensions and all that

It is shown that the euclideanized Yukawa theory, with the Dirac fermion belonging to an irreducible representation of the Lorentz group, is not bounded from below. A one parameter family of supersymmetric actions is presented which continuously interpolates between the N = 2 SSYM and the N = 2 supersymmetric topological theory. In order to obtain a theory which is bounded from below and satisfies Osterwalder-Schrader positivity, the Dirac fermion should belong to a reducible representation of the Lorentz group and the scalar fields have to be reinterpreted as the extra components of a higher dimensional vector field.

Compiler-assisted power optimization for clustered VLIW architectures

Clustered VLIW architectures solve the scalability problem associated with flat VLIW architectures by partitioning the register file and connecting only a subset of the functional units to a register file. However, inter-cluster communication in clustered architectures leads to increased leakage in functional components and a high number of register accesses. In this paper, we propose compiler scheduling algorithms targeting two previously ignored power-hungry components in clustered VLIW architectures, viz., instruction decoder and register file. We consider a split decoder design and propose a new energy-aware instruction scheduling algorithm that provides 14.5% and 17.3% benefit in the decoder power consumption on an average over a purely hardware based scheme in the context of 2-clustered and 4-clustered VLIW machines. In the case of register files, we propose two new scheduling algorithms that exploit limited register snooping capability to reduce extra register file accesses. The proposed algorithms reduce register file power consumption on an average by 6.85% and 11.90% (10.39% and 17.78%), respectively, along with performance improvement of 4.81% and 5.34% (9.39% and 11.16%) over a traditional greedy algorithm for 2-clustered (4-clustered) VLIW machine. (C) 2010 Elsevier B.V. All rights reserved.

Breast cancer and human papillomavirus infection: No evidence of HPV etiology of breast cancer in Indian women

Background: Two clinically relevant high-risk HPV (HR-HPV) types 16 and 18 are etiologically associated with the development of cervical carcinoma and are also reported to be present in many other carcinomas in extra-genital organ sites. Presence of HPV has been reported in breast carcinoma which is the second most common cancer in India and is showing a fast rising trend in urban population. The two early genes E6 and E7 of HPV type 16 have been shown to immortalize breast epithelial cells in vitro, but the role of HPV infection in breast carcinogenesis is highly controversial. Present study has therefore been undertaken to analyze the prevalence of HPV infection in both breast cancer tissues and blood samples from a large number of Indian women with breast cancer from different geographic regions. Methods: The presence of all mucosal HPVs and the most common high-risk HPV types 16 and 18 DNA was detected by two different PCR methods - (i) conventional PCR assays using consensus primers (MY09/11, or GP5 +/GP6+) or HPV16 E6/E7 primers and (ii) highly sensitive Real-Time PCR. A total of 228 biopsies and corresponding 142 blood samples collected prospectively from 252 patients from four different regions of India with significant socio-cultural, ethnic and demographic variations were tested. Results: All biopsies and blood samples of breast cancer patients tested by PCR methods did not show positivity for HPV DNA sequences in conventional PCRs either by MY09/11 or by GP5+/GP6+/HPV16 E6/E7 primers. Further testing of these samples by real time PCR also failed to detect HPV DNA sequences. Conclusions: Lack of detection of HPV DNA either in the tumor or in the blood DNA of breast cancer patients by both conventional and real time PCR does not support a role of genital HPV in the pathogenesis of breast cancer in Indian women.

Low-Complexity Detection and Performance in Multi-Gigabit High Spectral Efficiency Wireless Systems

Recently, we reported a low-complexity likelihood ascent search (LAS) detection algorithm for large MIMO systems with several tens of antennas that can achieve high spectral efficiencies of the order of tens to hundreds of bps/Hz. Through simulations, we showed that this algorithm achieves increasingly near SISO AWGN performance for increasing number of antennas in Lid. Rayleigh fading. However, no bit error performance analysis of the algorithm was reported. In this paper, we extend our work on this low-complexity large MIMO detector in two directions: i) We report an asymptotic bit error probability analysis of the LAS algorithm in the large system limit, where N-t, N-r -> infinity keeping N-t = N-r, where N-t and N-r are the number of transmit and receive antennas, respectively. Specifically, we prove that the error performance of the LAS detector for V-BLAST with 4-QAM in i.i.d. Rayleigh fading converges to that of the maximum-likelihood (ML) detector as N-t, N-r -> infinity keeping N-t = N-r ii) We present simulated BER and nearness to capacity results for V-BLAST as well as high-rate non-orthogonal STBC from Division Algebras (DA), in a more realistic spatially correlated MIMO channel model. Our simulation results show that a) at an uncoded BER of 10(-3), the performance of the LAS detector in decoding 16 x 16 STBC from DA with N-t = = 16 and 16-QAM degrades in spatially correlated fading by about 7 dB compared to that in i.i.d. fading, and 19) with a rate-3/4 outer turbo code and 48 bps/Hz spectral efficiency, the performance degrades by about 6 dB at a coded BER of 10(-4). Our results further show that providing asymmetry in number of antennas such that N-r > N-t keeping the total receiver array length same as that for N-r = N-t, the detector is able to pick up the extra receive diversity thereby significantly improving the BER performance.

Solid finite elements through three decades

conventionally, solid finite elements have been looked upon as just generalizations of two-dimensional finite elements. In this article we trace their development starting from the days of their inception. Keeping in tune with our perceptions on developing finite elements, without taking recourse to any extra variational techniques, we discuss a few of the techniques which have been applied to solid finite elements. Finally we critically examine our own work on formulating solid finite elements based on the solutions to the Navier equations.