Algorithms to Compute the Lyndon Array

We first describe three algorithms for computing the Lyndon array that have been suggested in the literature, but for which no structured exposition has been given. Two of these algorithms execute in quadratic time in the worst case, the third achieves linear time, but at the expense of prior computation of both the suffix array and the inverse suffix array of x. We then go on to describe two variants of a new algorithm that avoids prior computation of global data structures and executes in worst-case n log n time. Experimental evidence suggests that all but one of these five algorithms require only linear execution time in practice, with the two new algorithms faster by a small factor. We conjecture that there exists a fast and worst-case linear-time algorithm to compute the Lyndon array that is also elementary (making no use of global data structures such as the suffix array)

Giffen behaviour for rice consumption in rural Bangladesh

Rice is the staple food in Bangladesh. Thus, the price of rice is an important economic factor in Bangladesh especially for poor people. In Bangladesh, during the price hike of 2008-09, rice price increased by 40% on an average across the country. Interestingly, the consumption of rice in some rural parts of Bangladesh also increased during that period. Thus, the focus of this paper is to examine the practical evidence of this positive relationship between the consumption of rice and increasing price which is addressed as Giffen behavior (inverse of normal behavior) for rice consumption in Bangladesh. By analyzing secondary data obtained from some specific rural parts namely Patharghata (Barguna), Chaddagham (Comilla), Sadar (Jamalpur), Kaligang (Jhenaidaha), Sreemangal (Moulvibazar) and Sadar (Naogaon) of Bangladesh, we have found a new insight in this context. We find that the price elasticity of staple food for the poor people depends significantly and nonlinearly on the severity of their poverty. In order to have an effective design of welfare for the poor people, we need to understand this heterogeneity of their consumption behavior

Kombinasi Teknik Proprioceptive Neuromuscular Facilita Tion Dan Mc.kenzie Exercise Lebih Efektif Daripada Mc.ken Zie Exercise Terhadap Perubahan Fungsional Lumbal Pada Penderita Hnp Lumbal

Latar Belakang : Ischialgia merupakan keluhan nyeri yang terjadi di sepanjang perjalanan nervus ischiadicus. Sebagian besar disebabkan oleh penjepitan akar saraf L4-L5 dan L5-S1 yang biasa dikenal dengan Hernia Nukleus Pulposus. HNP lumbal sering disebabkan oleh kebiasaan postur yang jelek saat melakukan aktivitas pekerjaan yang berlangsung lama. Keluhan ischialgia akan menghambat gerak fungsional lumbal. Metode : Penelitian ini adalah penelitian eksperimen dengan randomized pre test – post test control group design yang bertujuan untuk mengetahui efektifitas penambahan teknik PNF pada intervensi TENS dan Mc.Kenzie Exercise dibandingkan dengan TENS dan Mc.Kenzie Exercise saja terhadap perbaikan fungsional lumbal pada penderita ischialgia akibat HNP lumbal, dilaksanakan di RSAD. Tk.II Pelamonia, jumlah sampel yang didapatkan sebanyak 20 orang (sesuai dengan kriteria inklusi) diacak kedalam 2 kelompok yaitu kelompok perlakuan sebanyak 10 orang yang diberikan TENS, Mc.Kenzie Exercise dan teknik PNF, serta kelompok kontrol sebanyak 10 orang diberikan TENS dan Mc.Kenzie Exercise. Alat ukur yang digunakan untuk pengumpulan data adalah skala Back Bournemouth Questionnaire. Hasil : Hasil penelitian berdasarkan hasil uji paired sample t pada kelompok perlakuan diperoleh nilai p = 0,000 < 0,05 yang berarti bahwa TENS, Mc.Kenzie Exercise dan teknik PNF dapat menghasilkan perbaikan fungsional lumbal yang signifikan sedangkan pada kelompok kontrol diperoleh nilai p = 0,000 < 0,05 yang berarti bahwa TENS dan Mc.Kenzie Exercise dapat menghasilkan perbaikan fungsional lumbal yang signifikan pada penderita ischialgia akibat HNP lumbal. Kemudian berdasarkan hasil uji independent sample t diperoleh nilai p = 0,000 < 0,05 yang berarti bahwa penambahan teknik PNF pada intervensi TENS dan Mc.Kenzie Exercise lebih efektif daripada TENS dan Mc.Kenzie Exercise saja terhadap perbaikan fungsional lumbal pada penderita ischialgia akibat HNP lumbal. Kesimpulan : Dapat disimpulkan bahwa penambahan teknik PNF pada intervensi TENS dan Mc.Kenzie Exercise lebih efektif daripada TENS dan Mc.Kenzie Exercise saja terhadap Perubahan fungsional lumbal pada penderita ischialgia akibat HNPlumbal

Doping Dependence of Thermal Oxidation on n-type 4H-SiC

The doping dependence of dry thermal oxidation rates in n-type 4H-SiC was investigated. The oxidation was performed in the temperature range 1000C to 1200C for samples with nitrogen doping in the range of 6.5e15/cm3 to 9.3e18/cm3, showing a clear doping dependence. Samples with higher doping concentrations displayed higher oxidation rates. The results were interpreted using a modified Deal-Grove model. Linear and parabolic rate constants and activation energies were extracted. Increasing nitrogen led to an increase in linear rate constant pre-exponential factor from 10-6m/s to 10-2m/s and the parabolic rate constant pre-exponential factor from 10e9m2/s to 10e6m2/s. The increase in linear rate constant was attributed to defects from doping-induced lattice mismatch, which tend to be more reactive than bulk crystal regions. The increase in the diffusion-limited parabolic rate constant was attributed to degradation in oxide quality originating from the doping-induced lattice mismatch. This degradation was confirmed by the observation of a decrease in optical density of the grown oxide films from 1.4 to 1.24. The linear activation energy varied from 1.6eV to 2.8eV, while the parabolic activation energy varied from 2.7eV to 3.3eV, increasing with doping concentration. These increased activation energies were attributed to higher nitrogen content, leading to an increase in effective bond energy stemming from the difference in C-Si (2.82eV) and Si-N (4.26eV) binding energies. This work provides crucial information in the engineering of SiO2 dielectrics for SiC MOS structures, which typically involve regions of very different doping concentrations, and suggests that thermal oxidation at high doping concentrations in SiC may be defect mediated.Comment: 13 pages. 9 figures, accepted as a transiction in IEEE electron device. TED MS#8035

Magnetotransport properties of a magnetically modulated two-dimensional electron gas with the spin-orbit interaction

We study the electrical transport properties of a two-dimensional electron gas with the Rashba spin-orbit interaction in presence of a constant perpendicular magnetic field $(B_0 \hat z)$ which is weakly modulated by ${\bf B_1} = B_1 \cos (q x) \hat z$, where $B_1 \ll B_0$ and $q = 2 \pi/a$ with $a$ is the modulation period. We obtain the analytical expressions of the diffusive conductivities for spin-up and spin-down electrons. The conductivities for spin-up and spin-down electrons oscillate with different frequencies and produce beating patterns in the amplitude of the Weiss and Shubnikov-de Haas oscillations. We show that the Rashba strength can be determined by analyzing the beating pattern in the Weiss oscillation. We find a simple equation which determines the Rashba spin-orbit interaction strength if the number of Weiss oscillations between any two successive nodes is known from the experiment. We compare our results with the electrically modulated 2DEG with the Rashba interaction. For completeness, we also study the beating pattern formation in the collisional and the Hall conductivities.Comment: 11 pages, 5 figures, re-written with new result

Correlation energies by the generator coordinate method: computational aspects for quadrupolar deformations

We investigate truncation schemes to reduce the computational cost of calculating correlations by the generator coordinate method based on mean-field wave functions. As our test nuclei, we take examples for which accurate calculations are available. These include a strongly deformed nucleus, 156Sm, a nucleus with strong pairing, 120Sn, the krypton isotope chain which contains examples of soft deformations, and the lead isotope chain which includes the doubly magic 208Pb. We find that the Gaussian overlap approximation for angular momentum projection is effective and reduces the computational cost by an order of magnitude. Cost savings in the deformation degrees of freedom are harder to realize. A straightforward Gaussian overlap approximation can be applied rather reliably to angular-momentum projected states based on configuration sets having the same sign deformation (prolate or oblate), but matrix elements between prolate and oblate deformations must be treated with more care. We propose a two-dimensional GOA using a triangulation procedure to treat the general case with both kinds of deformation. With the computational gains from these approximations, it should be feasible to carry out a systematic calculation of correlation energies for the nuclear mass table.Comment: 11 pages revtex, 9 eps figure

Strengthening primary health care and family planning services in Pakistan: some critical issues

Objective: The Lady Health Workers (LHWs) under the Ministry of Health and the Village-based Family Planning Workers (VBFPWs) under the Ministry of Population Welfare are mandated to bring services to the people and are often the only health care resource available particularly for women. This study was conducted to understand the problems faced by the LHWs and VBFPWs in their routine work.STUDY Design: A situational analysis followed by focus group discussions conducted with a cross-section of LHWs and VBFPWs in four districts, one from each province.Results: Findings reveal that LHWs and VBFPWs are faced with a number of problems that severely limit their effectiveness. Findings suggest that the population/health worker ratios vary considerably from one district to another. Moreover, these two categories of workers differ considerably in terms of level of education, training and skills. There is lack of well-designed client record cards, proper training and backup support, including emergency obstetric care, to cover the range of essential services demanded by the consumers and a lack of information feedback.CONCLUSION: These issues need to be recognized and addressed to further strengthen primary health care and family planning services in the country. The paper presents some of the important findings of the survey and focus group discussions conducted by the Community Health Sciences Department of the Aga Khan University as part of a broader study funded by the United Nations Population Fund. These findings have serious implications for future primary health care and family planning policies in Pakistan