A comprehensive analysis of degree based condition for Hamiltonian cycles

Hasan, Md. Kamrul,Kaykobad, Mohammad,Lee, Young-Koo,Lee, Sungyoung Elsevier 2010 Theoretical computer science Vol.411 No.1

<P><B>Abstract</B></P><P>Since finding whether a graph has a Hamiltonian path or Hamiltonian cycle are both NP-complete problems, researchers have been formulating sufficient conditions that ensure the path or cycle. Rahman and Kaykobad (2005) <ce:cross-ref refid='b2'>[2]</ce:cross-ref> presented a sufficient condition for determining the existence of Hamiltonian path. Three recent works–Lenin Mehedy, Md. Kamrul Hasan, Mohammad Kaykobad (2007) <ce:cross-ref refid='b3'>[3]</ce:cross-ref>, Rao Li (2006) <ce:cross-ref refid='b4'>[4]</ce:cross-ref>, Shengjia Li, Ruijuan Li, Jinfeng Feng (2007) <ce:cross-ref refid='b5'>[5]</ce:cross-ref>–further used the same or similar condition to ensure Hamiltonian cycle with some exceptions. The three works, along with their unique findings, have some common results. This paper unifies the results and brings them under Rahman and Kaykobad’s condition.</P>

Focus Intonation in Bengali

( Md Kamrul Hasan ) 범태평양 응용언어학회 2015 Journal of Pan-Pacific Association of Applied Ling Vol.19 No.1

This work attempts to investigate the role of prosody in the syntax of focus in Bangla. The aim of this study is to show the intonation pattern of Bangla in emphasis and focus. In order to do that, the author has looked at the pattern of focus without-i/o as well as with the same. Do they really pose any different focus intonation pattern from Lahiri and Cole (1999) and others or not-that is also examined in the course of the discussion. The current study reports the finding that the focus intonation in Bangla is H*L1 rather than L *Hp as reported by Hayes and Lahiri. The intonation can be accompanied by shades of meaning. Once a particular intonation contour has been isolated; its meaning can be determined by the emotional situations within which that contour occurs. According to the speaker``s momentary feeling about the subject matter, most sentences or parts of sentences can be pronounced with several different intonation contours. These attitudes can vary from surprise, to deliberation, to sharp isolation of some part of a sentence for attention, to mild intellectual detachment. Intonation in Bangla can have emotive function. This is shown by the examples and figures of (18), (24) and (25) cited in the discussion. The same kind of study of Bangla can be traced in other studies as well; such as the study of Isamu Abe (1955) and Kenneth Pike (1945) would be greater importance in this regard. The focus intonation pattern with clitics and without clitics of Bangla also can be added to form our argument. The examples of (11), (19), (20), (23), (26) with clitics and other examples without clitics and relative figures prove this point. They follow uniform phonological shape of H*L1 of Bangla.

Thermal deformation analysis of tabbed solar cells using solder alloy and conductive film

Md. Kamrul Hasan,Katsuhiko Sasaki 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.7

Finite element analysis (FEA) has been carried out with the aim of understanding the thermal deformation characteristics of two solar cell configurations. One of the solar cell models is tabbed by lead-free solder, the other model by Conductive film (CF). A high temperature soldering process could weaken the bond and reduce the reliability of the cells because of the residual stress caused by the different thermal expansion coefficients of the materials. Moreover, solar irradiation generates temperature distribution across the surface of the solar cell, and the development of solar cells made of thinner crystalline silicon wafers will lead to the reduction in manufacturing costs. In this study, Finite element analysis (FEA) of the manufacturing process has been carried out using both solder and CF bonding. Three temperature cycles were applied to analyze different environmental operating conditions and understand how thermal cycles affect the residual stress during actual service conditions. This investigation provides a comparison of thermal deformations between solder and CF bonded solar cells in order to understand which offers substantial reliability in the long term. Also this study explores the effects of various thicknesses of the silicon wafer on the residual stress and deformation of the solar cells.

The Relationship of Sub-Components of Manifold Dimensions of Vocabulary Depth Knowledge and Academic Reading Comprehension among English as a Foreign Language Learners at Tertiary Level

( Md. Kamrul Hasan ),( Ahmad Affendi Shabdin ) 범태평양 응용언어학회 2017 Journal of Pan-Pacific Association of Applied Ling Vol.21 No.1

This study makes an attempt to investigate the correlations between manifold aspects, namely both syntagmatic and paradigmatic relations, the four major derivative word forms, which represented morphological knowledge, six dimensions of analytic relations (i.e. component-integral, member-collection, portion-mass, stuff-object, feature-activity, and place-area) of vocabulary depth knowledge and academic reading comprehension among English as a Foreign Language learners at tertiary level. To this end, ninety one students from three departments of Business school and sixty four Engineering students (two departments) took part voluntarily in three depth of vocabulary knowledge tests and one reading comprehension test, which consisted of three reading passages with followed multiple choice questions. Results showed that firstly, analytic relations, which represented depth of vocabulary knowledge was positively and significantly correlated with reading comprehension. In other words, those students who gained more analytical relations (part-whole) knowledge performed better in reading comprehension than students with morphological knowledge and syntagmatic and paradigmatic relations, which represented depth of vocabulary knowledge. Secondly, students who had more paradigmatic (synonyms) relation knowledge performed better in reading comprehension than those who had syntagmatic relation (collocations), one of the two subtests of vocabulary depth knowledge test. Thirdly, the four major derivational word forms, i.e. noun, verb, adjective, and adverb were positively and either strongly or moderately correlated with dependent variable, academic reading comprehension. Fourthly, except one aspect of analytic relations, i.e. stuff-object analytic relations aspect, the rest of other five dimensions of analytic relations, namely component-integral, portion-mass, member-collection, place-area, and feature-activity analytic relations facets were positively and either strongly or moderately correlated with dependent variable, academic reading comprehension.

Individual and Social- Psychological Variables Related to Bangladeshi Students and Their Proficiency in ESL

Md. Kamrul Hasan 아시아영어교육학회 2010 The Journal of Asia TEFL Vol.7 No.1

Service Discovery Using Broadcasting Data Channel

( Md Kamrul Hasan ),( Husne Ara Rubaiyeat ),( Sungyoung Lee ),( Young-koo Lee ) 한국정보처리학회 2010 한국정보처리학회 학술대회논문집 Vol.17 No.1

Traditional service discovery mechanisms so far necessitate centralized registry containing all the service descriptions. Though centralized service registration is intuitive, it does not facilitate users in their usual ways of doing things. Moreover, centralized repository is not scalable for high query rate. We propose that service description be broadcast through the advertising data channels so that computers can parse and queue the service descriptions interesting to the users. The current technologies such as Digital Media Broadcast (DMB), Car Navigation Systems and Wireless Broadband can bring our idea to reality.

Blind Deconvolution of Ultrasound Images Using <tex> $l_{1}$</tex>-Norm-Constrained Block-Based Damped Variable Step-Size Multichannel LMS Algorithm

Hasan, Md. Kamrul,Rabbi, Md. Shifat-E-,Lee, Soo Yeol IEEE 2016 and Frequency Control Vol.63 No.8

<P>The problem of improving the ultrasound image resolution by undoing the effect of convolution on backscattered radio-frequency (RF) data caused by the point spread function (PSF) of ultrasonic imaging system is one of the key problems in the reconstruction of the medical ultrasound images. In this paper, the tissue reflectivity functions (TRFs) are directly estimated from the noisy and nonstationary RF data using the block-based multichannel least-mean square (l(1)-bMCLMS) algorithm without any prior knowledge of the PSF. To account for the nonstationarity and incomplete acquisition problem of the ultrasound RF data a modified block-based cross-relation equation has been developed. An l(1)-norm regularized cost function based on the proposed modified cross-relation equation is then formulated for blind estimation of the TRFs using the new l(1)-bMCLMS algorithm. A damped variable step-size is also developed to compensate for the noise effect and to improve the convergence speed of the algorithm. The PSF is then estimated from multiple lateral blocks of RF data using the regularized multiple-input/output inverse theorem, which is known to be suitable for both minimum and nonminimum phase signals. The salient feature of the proposed method is that no basis function is required for TRFs and/or PSF. The efficacy of the proposed method is examined using the simulation/experimental phantom data and in vivo RF data and evaluated in terms of the quality metrics: resolution gain (RG), normalized projection misalignment (NPM), and shifted normalized mean square error (snMSE). The results show that the RG and NPM improvements of TRFs estimation of 0.12 similar to 5.2 and 3.34 similar to 22.82 dB, respectively, and the snMSE improvement of the PSF estimation of the order 10(2 similar to 4) can be achieved in our technique as compared with the other techniques in the literature.</P>

Direct Mean Strain Estimation for Elastography Using Nearest-Neighbor Weighted Least-Squares Approach in the Frequency Domain

Hasan, Md. Kamrul,Anas, Emran Mohammad Abu,Alam, S. Kaisar,Lee, Soo Yeol Elsevier 2012 Ultrasound in medicine & biology Vol.38 No.10

<P>Ultrasound elastography is emerging with enormous potential as a medical imaging modality for effective discrimination of pathological changes in soft tissue. It maps the tissue elasticity or strain due to a mechanical deformation applied to it. The strain image most often calculated from the derivative of the local displacement field is highly noisy because of the de-correlation effect mainly due to unstable free-hand scanning and/or irregular tissue motion; consequently, improving the SNR of the strain image is still a challenging problem in this area. In this paper, a novel approach using the nearest-neighbor weighted least-squares is presented for direct estimation of the 'mean' axial strain for high quality strain imaging. Like other time/frequency domain reported schemes, the proposed method exploits the fact that the post-compression rf echo signal is a time-scaled and shifted replica of the pre-compression rf echo signal. However, the elegance of our technique is that it directly computes the mean strain without explicitly using any post filter and/or previous local displacement/strain estimates as is usually done in the conventional approaches. It is implemented in the short-time Fourier transform domain through a nearest-neighbor weighted least-squares-based Fourier spectrum equalization technique. As the local tissue strain is expected to maintain continuity with its neighbors, we show here that the mean strain at the interrogative window can be directly computed from the common stretching factor that minimizes a cost function derived from the exponentially weighted windowed pre- and post-compression rf echo segments in both the lateral and axial directions. The performance of our algorithm is verified for up to 8% applied strain using simulation and experimental phantom data and the results reveal that the SNR of the strain image can be significantly improved compared to other reported algorithms in the literature. The efficacy of the algorithm is also tested with in vivo breast data known to have malignant or benign masses from histology.</P>

Reviewing the Challenges and Opportunities Presented by Code Switching and Mixing in Bangla

Md. Kamrul Hasan,Mohd. Moniruzzaman Akhand 범태평양 응용언어학회 2014 범태평양응용언어학회지 Vol.18 No.2

This paper investigates the issues related to code-switching/codemixing in an ESL context. Some preliminary data on Bangla-English code-switching/code-mixing has been analyzed in order to determine which structural pattern of code-switching/code-mixing is predominant in different social strata. This study also explores the relationship of language use to the socioeconomic class of the language user. The redefined concept of modernization, the increased number of crosscultural contact and the need for language innovation play a dominant role in the language user``s application of code-switching/mixing that determine the socioeconomic rank. Out of four major types of codeswitching/ mixing, our focus of interest is on "inter-sentential mixing`` and ``intra-sentential mixing`` i.e. where elements are mixed from both languages that are used in the same sentence and/or in the same conversation. The context and factors that lead to the motivation of using L1 and L2 in a social milieu are also explored in this paper. Our findings suggest that the users are concerned about the language during their speech in order to establish and/or to realize social function, pragmatic function, and meta-linguistic function.

Seismic evaluation of different types of electrical cabinets in nuclear power plants considering coupling effects: Experimental and numerical study

Ikbal Md Kamrul Hasan,Nguyen Dong Van,김석철,김두기 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.9

The objective of this research is to assess the seismic performance of different types of electrical cabinets in nuclear power plants. The cabinets under investigation are: (a) Case 1: a short single cabinet; (b) Case 2: a tall single cabinet; (c) Case 3: separated cabinets; and (d) Case 4: a combined cabinet with coupling effects. To accurately capture the real behavior of the cabinet, three-dimensional finite element models are developed using ANSYS with connection non-linearity. Frequency domain decomposition (FDD) is used to determine the dynamic properties of the cabinets from shaking table testing data, and these results are utilized to validate the numerical model. The close match between the experimental and numerical results obtained from the modal analysis demonstrates the accuracy of the numerical model. Subsequently, transient structural analysis is performed on the validated models to explore seismic performance. The results show that the acceleration response of the combined cabinet is lower than the single cabinet and the separated cabinet. This observation suggests that top anchors used to combine two different types of cabinets play a crucial role in assessing the efficiency and seismic resistance of electrical cabinets in a nuclear power plant.