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Impact of Community Education on Antenatal Care Visits in Bangladesh: A Multilevel Analysis 社区教育对孟加拉国产前保健访问的影响:一项多层次分析
Pub Date : 2019-01-30 DOI: 10.3329/dujs.v67i1.54570
Md Morshadur Rahman, Md Akhtar Hossain
Antenatal care (ANC) utilization has a great role in reducing pregnancy-related complications and maternal mortality. Besides individual demographic and socio-economic factors, community characteristics can influence a mother‟s decision to seek antenatal care visits. This study makes an attempt to determine the influence of community education on adequate ANC visits in Bangladesh by using Bangladesh Demographic and Health Survey (BDHS) 2014 data. Multilevel logistic regression model has been employed for the purpose of the analysis. Study findings showed a significant positive association of community education on adequate ANC visits. Other community and individual level covariates such as place of residence, region of residence, birth order, mother‟s age at birth, household wealth, media access, husband‟s education, decision making on health care also showed significant association with adequate ANC visits. Dhaka Univ. J. Sci. 67(1): 41-46, 2019 (January)
产前保健(ANC)的利用在减少与妊娠有关的并发症和孕产妇死亡率方面发挥着重要作用。除了个人人口统计和社会经济因素外,社区特征也会影响母亲寻求产前检查的决定。本研究利用2014年孟加拉国人口与健康调查(BDHS)的数据,试图确定社区教育对孟加拉国适当的ANC访问的影响。本文采用多水平逻辑回归模型进行分析。研究结果显示,社区教育与充分的ANC访问有显著的正相关关系。其他社区和个人水平的协变量,如居住地、居住地区、出生顺序、母亲的出生年龄、家庭财富、媒体访问、丈夫的教育程度、医疗保健决策也显示出与充分的ANC访问有显著关联。达卡大学学报,67(1):41-46,2019 (1)
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引用次数: 3
Conjugate Effects of Thermal and Mass Diffusion on Natural Convection Flow from a Heated Sphere with Internal Heat Generation or Absorption 热扩散和质量扩散对具有内部热产生或吸收的受热球体自然对流流动的共轭效应
Pub Date : 2019-01-30 DOI: 10.3329/dujs.v67i1.54565
Sadia Masud, N. C. Roy
We examine the conjugate effects of thermal and mass diffusion on the unsteady natural convection flow from a heated sphere. The mathematical model of the problem is made into a system of nonsimilar partial differential equations introducing appropriate transformations. We solve this system employing the implicit finite difference technique. Numerical solutions have been elucidated with the skin friction as well as heat and mass transfer for varying Prandtl number, Schmidt number, combined buoyancy parameter, and heat generation or absorption parameter. Dhaka Univ. J. Sci. 67(1): 13-20, 2019 (January)
我们研究了热扩散和质量扩散对加热球体非定常自然对流流动的共轭效应。将该问题的数学模型转化为引入适当变换的非相似偏微分方程组。我们采用隐式有限差分技术求解该系统。在普朗特数、施密特数、联合浮力参数、生热或吸热参数变化的情况下,给出了表面摩擦和传热传质的数值解。达卡大学学报(自然科学版),67(1):13- 20,2019 (1)
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引用次数: 0
Determination of Trace Amount of Iron with as-Triazine Containing Ferroin- Functional Group 含铁三嗪官能团法测定痕量铁
Pub Date : 2019-01-01 DOI: 10.3329/dujs.v67i2.54588
M. Hossain, Md. Anwarul Islam, S. Begum, Maksuda Parvin
The as-triazines containing iron(II) methine chromophoric group; 3-(2-pyridyl)-5,6-diphenyl-as-triazine (PDT), and 3-(2- pyridyl)-5,6-bis(p-methoxyphenyl)-as-triazine (PBMPT) have been prepared from commercially available relatively cheaper reagents. The absorptiometric characteristics of the iron(II) complexes with PDT and PBMPT have been re-evaluated. The interference of copper ion on the determination of iron with these selective reagents and its masking has also been studied. The application of these spectrophotometric reagents for determination of iron in water samples based on the formation of extractable PDT-iron(II) and PBMPT-iron(II) complexes in chloroform medium has been described. Standard addition technique was used to verify the reliability of the method. Repeated determinations gave results with a very small standard deviation. Dhaka Univ. J. Sci. 67(2): 145-150, 2019 (July)
含铁(II)甲基显色基团的as-三嗪类;3-(2-吡啶基)-5,6-二苯基-三嗪(PDT)和3-(2-吡啶基)-5,6-双(对甲氧基苯基)-三嗪(PBMPT)是由市售的相对便宜的试剂制备的。重新评价了铁(II)配合物与PDT和PBMPT的吸收特性。研究了铜离子对这些选择性试剂测定铁的干扰及其掩蔽作用。描述了这些分光光度试剂在氯仿介质中形成可萃取的pdt -铁(II)和pbmpt -铁(II)配合物的基础上测定水样中铁的应用。采用标准加入技术验证了方法的可靠性。重复测定的结果标准差非常小。达卡大学学报,67(2):145-150,2019 (7)
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引用次数: 3
Determination of Optimal Smoothing Constants for Holt - Winter’s Multiplicative Method Holt - Winter乘法法最优平滑常数的确定
Pub Date : 2019-01-01 DOI: 10.3329/dujs.v67i2.54580
M. N. Dhali, Nandita Barman, M. B. Hasan
There are many trade time series parade having seasonality. This paper ponders on taking the appropriate smoothing constants of seasonal time series data using Holt-Winter’s exponential smoothing method in demand forecasting of toy production in a company. It is a quantitative technique in forecasting. This forecasting method is used three constants that assign weights to current demands and previous forecasts to decide on a new forecast. We have demonstrated the techniques how to choose these constants by presenting a real life example and calculated corresponding forecast value of this technique for the optimal smoothing constants. Dhaka Univ. J. Sci. 67(2): 99-104, 2019 (July)
有许多贸易时间序列游行具有季节性。本文探讨了利用Holt-Winter指数平滑法对季节时间序列数据选取合适的平滑常数进行玩具生产需求预测的问题。这是一种定量预测技术。这种预测方法使用三个常量,为当前需求和以前的预测分配权重,以确定新的预测。通过一个实际的例子说明了如何选择这些常数的技术,并计算了该技术对最佳平滑常数的相应预测值。达卡大学学报(自然科学版),67(2):99-104,2019 (7)
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引用次数: 1
Analysis of Antenatal Care Visit Data in Bangladesh Using Zero Modified Count Regression Model 使用零修正计数回归模型分析孟加拉国产前保健访问数据
Pub Date : 2019-01-01 DOI: 10.3329/dujs.v67i2.54583
N. Ahmed, T. S. Mallick
In medical science, pharmaceutical studies, public health and socio-economic researches we often encounter the situation of excess of zeros in count data. This preponderance of zeros leads to overdispersion. In such cases traditional count data regression models like Poisson and negative binomial (NB) regression may not be pertinent for inference. The two most commonly used types of model that have been developed to adjust for excessivezeros in count data are Hurdle and zero-inflated models. In this study we have analyzed the antenatal care (ANC) visit data of pregnant women in Bangladesh using traditional and zero-modified count models. Based on the model selection criteria, we found that negative binomial hurdle model fits the data best. Through this analysis,we have perceived that the variables age of mother, division, birth order (order a child is born), place of residence, economic condition, media exposure of the mother, mainaccess road to village and education gap between husband and wife have significant impact on the mean number of ANC visits taken. Dhaka Univ. J. Sci. 67(2): 117-122, 2019 (July)
在医学、药物研究、公共卫生和社会经济研究中,我们经常遇到计数数据中超过零的情况。这种零的优势导致过色散。在这种情况下,传统的计数数据回归模型,如泊松和负二项回归(NB)可能不适合推理。为调整计数数据中过多的零而开发的两种最常用的模型类型是障碍模型和零膨胀模型。在本研究中,我们使用传统和零修改计数模型分析了孟加拉国孕妇的产前护理(ANC)访问数据。根据模型选择标准,我们发现负二项障碍模型最适合数据。通过这一分析,我们发现,母亲的年龄、分工、出生顺序(孩子出生的顺序)、居住地、经济条件、母亲的媒体曝光率、通往村庄的主要通道以及夫妻之间的教育差距等变量对ANC的平均访问次数有显著影响。达卡大学学报(自然科学版),67(2):117- 122,2019 (7)
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引用次数: 0
Electromagnetics in Terms of Differential Forms 微分形式下的电磁学
Pub Date : 2019-01-01 DOI: 10.3329/dujs.v67i1.54564
H. Hena, Jenita Jahangir, Md. Showkat Ali
The calculus of differential forms has been applied to electromagnetic field theory in several papers and texts, some of which are cited in the references. Differential forms are underused in applied electromagnetic research. Differential forms represent unique visual appliance with graphical apprehension of electromagnetic fields. We study the calculus of differential forms and other fundamental principle of electromagnetic field theory. We hope to show in this paper that differential forms make Maxwell’s laws and some of their basic applications more intuitive and are a natural and powerful research tool in applied electromagnetics. Dhaka Univ. J. Sci. 67(1): 1-4, 2019 (January)
微分形式的微积分已经在一些论文和文本中应用于电磁场理论,其中一些在参考文献中被引用。微分形式在应用电磁研究中未得到充分利用。微分形式是一种独特的视觉工具,具有对电磁场的图形理解。我们学习微分形式的微积分和电磁场理论的其他基本原理。我们希望在本文中表明,微分形式使麦克斯韦定律及其一些基本应用更加直观,是应用电磁学中一种自然而有力的研究工具。达卡大学学报:自然科学版,67(1):1-4,2019 (1)
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引用次数: 0
The Effects of Birth Spacing on Nutritional Status in the form of Stunting of Under Five Children in Bangladesh: Evidence Based on BDHS, 2014 Data 出生间隔对孟加拉国五岁以下儿童营养状况(表现为发育迟缓)的影响:基于BDHS的证据,2014年数据
Pub Date : 2019-01-01 DOI: 10.3329/dujs.v67i2.54587
Mahfuzur Rahman Khokan
In this paper, it has been examined the effect of preceding birth interval on nutritional status in the form of Stunting of the children aged under 5 years of age in Bangladesh.For the purpose of the analysis, Bangladesh Demographic and Health Survey (BDHS), 2014 data has been used. The study cases are the children under 5 years aged born during last delivery of their mother. The response variable is Nutritional Status of under 5 year children in the form of stunting. The key independent variables is the length of the preceding birth interval, measured as the number of months between the births of the child under study.Bivariate analysis along with a Chi-square test has been performed to examine the association between preceding birth interval and stunting of the children. To determine the effect of preceding birth interval, three different logistic regression models (Model-I: considering only the preceding birth intervals, Model-II: covariate of model-I along with demographic and socioeconomic factors and Model-III: covariates of model-II along with health related factors) were considered.  The occurrence of stunting has been found to be inversely related with the preceding birth interval for the children aged under 5 years in Bangladesh. This inverse association has been found statistically significant for three models.After adjusting the demographic, socio-economic and health-related factors, the OR (odds ratio) shows that the percentage of being stunted is 73% higher for the children whose preceding birth interval is less than 24 (<24) while it is 37% higher for the children whose preceding birth interval is between months compared to whose birth interval is more than 60 (60>) months with 99% confidence interval (1.27, 2.36)***and (1.07, 1.45)***respectively. Dhaka Univ. J. Sci. 67(2): 139-144, 2019 (July)
在这篇论文中,它已经检查了之前的出生间隔对营养状况的影响,在孟加拉国的5岁以下儿童发育迟缓的形式。为进行分析,使用了2014年《孟加拉国人口与健康调查》的数据。研究案例是母亲最后一次分娩时出生的5岁以下儿童。反应变量是5岁以下儿童的营养状况,表现为发育迟缓。关键的自变量是前出生间隔的长度,以被研究儿童出生之间的月数来衡量。采用双变量分析和卡方检验来检验产前间隔与儿童发育迟缓之间的关系。为了确定前生育间隔的影响,考虑了三种不同的逻辑回归模型(模型1:仅考虑前生育间隔,模型2:模型1的协变量与人口统计学和社会经济因素,模型3:模型2的协变量与健康相关因素)。在孟加拉国,已发现5岁以下儿童发育迟缓的发生与之前的出生间隔成反比。这种负相关关系在三个模型中具有统计学意义。在调整了人口统计学、社会经济和健康相关因素后,OR(比值比)显示,前出生间隔小于24个月的儿童发育迟缓的比例高出73%,其99%的置信区间分别为(1.27,2.36)***和(1.07,1.45)***。达卡大学学报(自然科学版),67(2):139- 144,2019 (7)
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引用次数: 1
Over-Differencing and Forecasting with Non-Stationary Time Series Data 非平稳时间序列数据的过差分与预测
Pub Date : 2019-01-01 DOI: 10.3329/dujs.v67i1.54568
Z. Hossain, Atikur Rahman, Moyazzem Hossain, J. Karami
In time series analysis, over-differencing is a common phenomenon to make the data to be stationary. However, it is not always a good idea to take over-differencing in order to ensure the stationarity of time series data. In this paper, the effect of over-differencing has been investigated via a simulation study to observe how far or how close the fitted model from the true one. Simulation results show that the fitted model is found to be different and very far from the true model because of over-differencing in most of the scenarios considered in this study. In practice, it may be worthy to consider differencing as well as suitable transformation of the time series data to make it stationary. Both transformation and differencing are used for a non-stationary time series data on average monthly house prices to ensure it to be stationary. We then analyse the data and make prediction for the future values. Dhaka Univ. J. Sci. 67(1): 21-26, 2019 (January)
在时间序列分析中,过度差分是使数据趋于平稳的一种常见现象。然而,为了保证时间序列数据的平稳性,采用过度差分并不总是一个好主意。本文通过仿真研究,考察了过度差分的影响,观察拟合模型与真实模型的距离。仿真结果表明,在本文考虑的大多数情景中,由于过度差异,拟合模型与真实模型存在很大差异。在实际应用中,可能值得考虑对时间序列数据进行差分和适当的变换,使其平稳。对月平均房价的非平稳时间序列数据,采用变换和差分相结合的方法,保证其平稳。然后我们分析数据并对未来的值进行预测。达卡大学学报:自然科学版,67(1):21-26,2019 (1)
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引用次数: 10
Isolation and Characterization of Two Cucurbitane Type Triterpenoid Glycocide from 1-Butanol Soluble Part of Momordica charantia Fruit Pulp Juice 苦瓜果肉汁1-丁醇可溶部分中两种葫芦烷型三萜糖苷的分离与表征
Pub Date : 2018-07-26 DOI: 10.3329/DUJS.V66I2.54560
M. Hossain, M. Hasan, M. Shoeb, M. Mamun, N. Nahar, M. Mosihuzzaman
Momordica charantia is a member of the Cucurbitaceae family having diverse biological activities. Two cucurbitane type triterpene glycoside have been isolated from 1-butanol soluble part of clear juice of M. charantia fruit pulp through column chromatography and HPLC. The isolated compounds were characterized as compound MC1 (3β, 7-O-β-glucopyranosyl-25-methoxy cucurbita –5-en-19-al) and compound MC2 (5β, 19-epoxy- 3- O-glucopyranosyl-25 methoxy cucurbita-6, 23-dien) with the help of UV Spectroscopy, Thin Layer Chromatography, IR Spectroscopy, 1H, 13C and dept-135 NMR. The proposed structures of the compounds were further confirmed by comparing the 13C-NMR values of the compounds with previous reported data. Dhaka Univ. J. Sci. 66(2): 145-149, 2018 (July)
苦瓜(Momordica charantia)是葫芦科植物,具有多种生物活性。采用柱层析法和高效液相色谱法,从白莲果果肉清汁的1-丁醇可溶性部分分离得到两个葫芦烷型三萜苷。通过紫外光谱、薄层色谱、红外光谱、1H、13C和深度-135核磁共振等手段对分离得到的化合物进行了表征,分别为化合物MC1 (3β, 7-O-β-葡萄糖吡喃基-25-甲氧基葫芦- 5-en-19-al)和化合物MC2 (5β, 19-环氧- 3- o -葡萄糖吡喃基-25-甲氧基葫芦- 6,23 -dien)。通过将化合物的13C-NMR值与先前报道的数据进行比较,进一步证实了化合物的结构。达卡大学学报,66(2):145-149,2018 (7)
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引用次数: 1
Bezier Polynomials with Applications Bezier多项式及其应用
Pub Date : 2018-07-26 DOI: 10.3329/dujs.v66i2.54562
Nazrul Islam, M. Islam
In this paper, we use the Galerkin technique for solving higher order linear and nonlinear boundary value problems (BVPs). The well-known Bezier polynomials are exploited as basis functions in the technique. To use the Bezier polynomials, we need to satisfy the corresponding homogeneous form of the boundary conditions and modification is thus needed. A rigorous matrix formulation is developed by the Galerkin method for linear and nonlinear systems and solved it using Bezier polynomials. The approximate solutions are compared to the exact solutions through tabular form. All problems are computed using the software MATHEMATICA. Dhaka Univ. J. Sci. 66(2): 157-162, 2018 (July)
本文利用伽辽金技术求解高阶线性和非线性边值问题。该技术利用了著名的贝塞尔多项式作为基函数。要使用Bezier多项式,需要满足相应齐次形式的边界条件,因此需要进行修改。采用伽辽金法建立了线性和非线性系统的严格矩阵公式,并用贝塞尔多项式进行求解。用表格的形式将近似解与精确解进行了比较。所有的问题都是用MATHEMATICA软件计算出来的。达卡大学学报:自然科学版,66(2):157-162,2018 (7)
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引用次数: 1
期刊
Dhaka University Journal of Science
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