• The Journal of Asian Finance, Economics and Business
• /
• v.8 no.5
• /
• pp.689-695
• /
• 2021

In the current technology-driven era, Small and medium enterprises (SMEs) have been deemed as one of the leading and prominent drivers of sustainable economic progress in emerging and developing economies such as in the Bangladesh context. Hence, it is of significance to understand what might fuel accelerating performance of SME business as increased SME performance will bring about more sustainability and strong development of SME sector within the country, through which more employment is anticipated to be generated. Therefore, the current study examines the impact of three factors: risk-taking, innovativeness, and proactiveness on SME performance in Bangladesh. The study has gathered data from SME entities in Dhaka city of Bangladesh, by applying a non-probability sampling strategy. 250 SME owners were contacted to act as respondents and finally, 180 SME owners fully completed the survey questionnaire, indicating that the final sample size is n=180. SPSS is used as a purpose of testing the hypotheses by considering a 5% significance level as acceptance criteria of the hypothesis. Hierarchical regression analysis was run to understand the impact of control variables and independent variables on SME performance and found that age of business, risk-taking, innovativeness, and proactiveness have an important impact on SME performance in Bangladesh.

• Journal of Electrochemical Science and Technology
• /
• v.10 no.3
• /
• pp.257-270
• /
• 2019

The inhibition performance of sodium gluconate (SG), cetyltrimethylammonium bromide (CTAB) and their mixture (SG/CTAB) on the corrosion behavior of ${\alpha}$-brass in 0.5 M $H_2SO_4$ solution has been investigated by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), Scanning Electron Microscope with Energy-Dispersive Spectrometer (SEM-EDS), Inductively Coupled Plasma Spectrometry (ICPS) and molecular dynamics (MD) simulation techniques. The results reveal that SG with 5ppm CTAB, noted SG/CTAB, acts as a good corrosion inhibitor and its inhibition efficiency reached 89% after 24 h immersion in sulfuric acid solution, but slightly decreased at higher temperatures. The polarization curves displayed that SG/CTAB acts as a cathodic-kind inhibitor. Electrochemical impedance spectroscopy (EIS) studies revealed that the addition of 5ppm CTAB to different concentrations of SG considerably increases the corrosion resistance of ${\alpha}$-brass. The SEM-EDS and ICPS analyses support the experimental results. Further, molecular dynamics (MD) simulations were used to understand the adsorption profiles of SG/CTAB on Cu(111) and Zn(111) surfaces.

• Journal of the Mineralogical Society of Korea
• /
• v.29 no.4
• /
• pp.209-220
• /
• 2016

Clay minerals are a major player to determine geochemical cycles of trace metals and carbon in the critical zone which covers the atmosphere down to groundwater aquifers. Molecular dynamics (MD) simulations can examine the Earth materials at an atomic level and, therefore, provide detailed fundamental-level insights related to physicochemical properties of clay minerals. In the current study, we have applied classical MD simulations with clayFF force field to dioctahedral clay minerals (i.e., gibbsite, kaolinite, and pyrophyllite) to analyze and compare structural parameters (lattice parameter, atomic pair distance) with experiments. We further calculated vibrational power spectra for the hydroxyls of the minerals by using the MD simulations results. The MD simulations predicted lattice parameters and interatomic distances respectively deviated less than 0.1~3.7% and 5% from the experimental results. The stretching vibrational wavenumber of the hydroxyl groups were calculated $200-300cm^{-1}$ higher than experiment. However, the trends in the frequencies among different surface hydroxyl groups of each mineral was consistent with experimental results. The angle formed by the surface hydroxyl group with the (001) plane and hydrogen bond distances of the surface hydroxyls were consistent with experimental result trends. The inner hydroxyls, however, showed results somewhat deviated from reported data in the literature. These results indicate that molecular dynamics simulations with clayFF can be a useful method in elucidating the roles of surface hydroxyl groups in the adsorption of metal ions to clay minerals.

• Korean Journal of Digital Imaging in Medicine
• /
• v.3 no.1
• /
• pp.126-132
• /
• 1997

Purpose : To apply to Program of Auto processor quality control after comparison of Film density variations with amendments to Auto density by using Check density program and Adjust density program of calibration mode into the Laser imager. Methods : Observe Check and Adjust density variations on the Control chart with standard step and value during seven months from December, 1995 to June, 1956 extending twice a week. (1) Measure density value on the steps after printing out 17-step sensitometric pattern of the Check density program. (2) In the same way, measure density values after amending density by using Adjust density program If they are exceeding allowable error limit. Results : In case of Check density program, the exceeding limit rates of Density difference(DD) and Middle density(MD) are: FL-IM3543 DD=75%. MD=72.5%, FL-IMD DD=0%. MD=30.8%(14.5%) After amending density by using Adjust density program, the exceeding limit rates of all both Laser imager were zero percent. The standard deviations are show lower FL-IM D than FL-IM3543 on the Check density control chart, but higher on the Adjust density control chart. Conclusion : (1) Check density variations by printingout sensitometric pattern extending once a week at least for quality control of the Laser imager. (2) In case of a dusty place, check the Laser beam transmission after cleaning Laser optical unit extending once a month. (3) Be sure to measure and check density values by using adjust density program if they are exceeding allowable error limit. (4) Maintain much better film density by performing the adjust density program even if check density values are existed within normal limit.

• Journal of Embryo Transfer
• /
• v.28 no.2
• /
• pp.113-119
• /
• 2013

The study focuses on the quality assessment of Black Bengal buck semen preserved at chilled condition. In this in vitro trial, collected semen from Black Bengal bucks was preserved at chilling temperature ($4{\sim}5^{\circ}C$) in tris-glucosecitrate yolk medium of 1:5 ratios for four days. Artificial Vagina (AV) method was utilized to collect semen from buck. General evaluation of semen includes the color, mass activity and density were measured by direct visual examination. However, computer-assisted sperm analysis (CASA) and phase contrast microscopy were used to figure out the motility (%), hyper-activated (HYP) motility (%) and number of abnormal spermatozoa (%) initially, and at every 24 h intervals. The result revealed that spermatozoa preserved at chilling temperature showed significantly (P<0.05) lower motility and HYP motility with the progression of preservation. The number of phenotypically abnormal spermatozoa significantly (P<0.05) increased following preservation. Although significant positive correlation (r=0.945; P<0.05) was existed between % motile and % HYP motile spermatozoa however, the % of morphologically abnormal spermatozoa was negatively correlated with % motile (r=-0.997; P<0.05) and % HYP motile spermatozoa (r=-0.946; P<0.01). Therefore, we concluded that the quality of chilled semen progressively losses its viability and doesn't remain useable after certain period of preservation with respect to its motility and morphology.

• Journal of Korean Society of Water and Wastewater
• /
• v.30 no.5
• /
• pp.511-519
• /
• 2016

Shale gas has become increasingly important as a viable alternative to conventional gas resources. However, one of the critical issues in the development of shale gas is the generation of produced water, which contains high concentration of ionic compounds (> TDS of 100,000 mg/L). Accordingly, membrane distillation (MD) was considered to treat such produced water. Experiments were carried out using a laboratory-scale direct contact MD (DCMD). Synthetic produced water was prepared to examine its fouling propensity in MD process. Antiscalants and in-line filtration were applied to control fouling by scale formation. Fouling rates (-dJ/dt) were calculated for in-depth analysis of fouling behaviors. Results showed that severe fouling occurred during the treatment of high range produced water (TDS of 308 g/L). Application of antiscalant was not effective to retard scale formation. On the other hand, in-line filtration increased the induction time and reduced fouling.

• Journal of Dental Anesthesia and Pain Medicine
• /
• v.20 no.5
• /
• pp.271-279
• /
• 2020

Background: The present study aimed to evaluate and compare the efficacy of buffered and unbuffered local anesthesia solutions during inferior alveolar nerve block (IANB) administration in children. Methods: PubMed, Ovid SP, and Cochrane databases were searched separately by two independent reviewers for potential papers published between 1980 and April 2020 using relevant MeSH terms and pre-specified inclusion and exclusion criteria. T Studies of IANB administration in children comparing buffered and unbuffered local anesthesia solutions were evaluated. The primary outcome evaluated was pain (perception and reaction), while the secondary outcome was the onset of anesthesia. Results: A total of five articles were included in a qualitative analysis; among them, four qualified for quantitative analysis of the primary outcome and three for quantitative analysis of the secondary outcome. A fixed-effects model was used to perform the meta-analysis. Pain perception (child-reported pain): Significantly lower pain scores were reported with buffered local anesthesia solution than with unbuffered solution (P = 0.006, MD: -0.32, 95% CI: -0.55 to -0.09). Pain reaction (observer-reported pain reaction in child): No significant difference was found between buffered and unbuffered solution in terms of observer-reported pain behavior in the child (P = 0.09, MD: -0.21, 95% CI: -0.46 to 0.04). Onset of anesthesia: A significantly lower duration of anesthesia onset was reported with buffered local anesthesia solution than with unbuffered solution (P = 0.00001, MD: -12.38, 95% CI: -17.64 to -7.13]. Conclusion: Buffering local anesthesia solution may reduce discomfort due to IANB injection administration and lower the initial onset time of anesthesia. More randomized control trials with adequate sample sizes should be carried out to validate the accuracy of these results.

• Journal of Acupuncture Research
• /
• v.38 no.1
• /
• pp.8-19
• /
• 2021

Low-level laser therapy including laser acupuncture (LLLT/LA) has been widely used for non-specific chronic low back pain (NCLBP). However, there is no critically appraised evidence of its potential benefits. This study aimed to evaluate the effectiveness of LLLT/LA for NCLBP. There were 12 databases (MEDLINE, CENTRAL, EMBASE, KoreaMed, KMBASE, KISS, NDSL, KISTI, OASIS, CNKI, CiNII, J-stage) searched for randomized controlled trials using LLLT/LA for NCLBP up until June 2019. The primary outcome was pain intensity and functional status/disability due to NCLBP. A random-effects meta-analysis was conducted on 20 studies involving 1,323 participants. LLLT/LA showed a significant positive effect on pain relief scores compared with sham treatments (SMD -0.51, 95% CI: -0.88 to -0.13; χ2 = 31.12, I2 = 74%). Alone, the therapy showed a significant positive effect on function/disability scores (30 participants, MD -11.90, 95% CI: -17.37 to -6.43). As an add-on treatment, it showed a significant positive effect on pain relief (80 participants, MD -5.10, 95% CI: -9.31 to -0.88; χ2 = 28.99, I2 = 97%) and improved function/disability scores (120 participants, MD 5.44, 95% CI: 2.19 to 8.68; χ2 = 4.07, I2 = 75%). Among 20 studies, 9 studies reported no adverse events and 1 study reported mild adverse events. LLLT/LA may be an alternative or add-on treatment for NCLBP.

• The Journal of the Acoustical Society of Korea
• /
• v.25 no.8
• /
• pp.356-361
• /
• 2006

We present the performance of differential space-time block decoders. which does not require the channel state information. We suggest the structure of the multiple blocks differential space time decoders. which does not require the channel state information, and analyze the Performances. In quasi-static flat fading channels. the Performance of multiple blocks differential detection (MD-STC) outperforms that of 2 blocks(D-STC) by 1.5dB. But in the time-selective fading channels due to Doppler frequency $(f_d)$, the performance of MD-STC degrades as the vehicular speed is greater than 200km/hr in 802.16e systems, where the data transmission rate is 144kbps.

• Natural Product Sciences
• /
• v.10 no.3
• /
• pp.99-100
• /
• 2004

A 5-C-methylcoumarin was isolated from the petroleum ether extract of Toona ciliata stem bark. Its structure was established as 7-Hydroxy-4-methoxy-5-methylcoumarin on the basis of spectral data, including 2D NMR.