A Survey of Software Development Process Models in Software Engineering

Iqbal H. Sarker1,Faisal Faruque,Ujjal Hossen,Atikur Rahman 보안공학연구지원센터 2015 International Journal of Software Engineering and Vol.9 No.11

Software has been a significant part of modern society for a long time. In particular, this paper is concerned with various software development process models. Software process model is a description of the sequence of activities carried out in a software engineering project, and the relative order of these activities. It represents some of the development models namely, waterfall, v-shaped, incremental, RAD, iterative spiral and agile model. Therefore, the main objective of this paper is to represent different models of software development and different aspects of each model to help the developers to select specific model at specific situation depending on customer demand.

Dynamic ID randomization for user privacy in mobile network

Arijet Sarker(Arijet Sarker ),SangHyun Byun(SangHyun Byun),Manohar Raavi(Manohar Raavi ),Jinoh Kim(Jinoh Kim),Jonghyun Kim(Jonghyun Kim),Sang-Yoon Chang(Sang-Yoon Chang) 한국전자통신연구원 2022 ETRI Journal Vol.44 No.6

Mobile and telecommunication networking uses temporary and random identifiers (IDs) to protect user privacy. For greater intelligence and security o the communications between the core network and the mobile user, we design and build a dynamic randomization scheme for the temporary IDs for mobile networking, including 5G and 6G. Our work for ID randomization (ID-RZ) advances the existing state-of-the-art ID re-allocation approach in 5G in the following ways. First, ID-RZ for ID updates is based on computing, as opposed to incurring networking for the re-allocation-based updates, and is designed for lightweight and low-latency mobile systems. Second, ID-RZ changes IDs proactively (as opposed to updating based on explicit networking event triggers) and provides stronger security (by increasing the randomness and frequency of ID updates). We build on the standard cryptographic primitives for security (e.g., hash) and implement our dynamic randomization scheme in the 5G networking protocol to validate its design purposes, which include time efficiency (two to four orders of magnitude quicker than the re-allocation approach) and appropriateness for mobile applications.

Mesoporous metal-organic framework PCN-222(Fe): Promising adsorbent for removal of big anionic and cationic dyes from water

Sarker, Mithun,Shin, Subin,Jeong, Jong Hwa,Jhung, Sung Hwa Elsevier 2019 Chemical engineering journal Vol.371 No.-

<P><B>Abstract</B></P> <P>Dyes are considered as harmful water pollutants because of their high water solubility, wide uses and toxicity. A highly mesoporous metal-organic framework PCN-222(Fe), together with commercial activated carbon (AC), was applied for the removal of both cationic (brilliant green (BG), crystal violet (CV), and methylene blue (MB)) and anionic (acid red 1 (AR 1), acid blue 80 (AB 80) and methyl orange (MO)) dyes from water through adsorption. The adsorptive performances of PCN-222(Fe) are much higher than AC for big dyes (BG, CV, AR 1, and AB 80). On the contrary, PCN-222(Fe) and AC show not very much different performances for the adsorption of small dyes (MB and MO). The maximum adsorption capacity of PCN-222(Fe) for BG, CV, AR 1, and AB 80 was higher than that of any reported adsorbent so far. The remarkably high adsorption capacity of PCN-222(Fe) for BG (854 mg·g<SUP>−1</SUP>), CV (812 mg·g<SUP>−1</SUP>), AR 1 (417 mg·g<SUP>−1</SUP>) and AB 80 (371 mg·g<SUP>−1</SUP>) could be explained by suitable pore size of PCN-222(Fe) together with electrostatic and π-π interactions. Moreover, PCN-222(Fe) could be successfully regenerated and reused for several cycles without any severe decrease in adsorption performance. Therefore, PCN-222(Fe) is suggested as an effective adsorbent for the dyes (especially with big size) removal from water.</P> <P><B>Highlight</B></P> <P> <UL> <LI> PCN-222(Fe) showed the highest adsorption capacity for studied four big dyes. </LI> <LI> PCN-222(Fe) was effective for removal of big dyes, different from that of small dyes. </LI> <LI> Adsorption could be explained by suitable pore size, electrostatic and π-π interactions. </LI> <LI> PCN-222(Fe) could be easily recycled by ethanol washing. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Detection and Recognition of Illegally Parked Vehicles Based on an Adaptive Gaussian Mixture Model and a Seed Fill Algorithm

Sarker, Md. Mostafa Kamal,Weihua, Cai,Song, Moon Kyou The Korea Institute of Information and Commucation 2015 Journal of information and communication convergen Vol.13 No.3

In this paper, we present an algorithm for the detection of illegally parked vehicles based on a combination of some image processing algorithms. A digital camera is fixed in the illegal parking region to capture the video frames. An adaptive Gaussian mixture model (GMM) is used for background subtraction in a complex environment to identify the regions of moving objects in our test video. Stationary objects are detected by using the pixel-level features in time sequences. A stationary vehicle is detected by using the local features of the object, and thus, information about illegally parked vehicles is successfully obtained. An automatic alarm system can be utilized according to the different regulations of different illegal parking regions. The results of this study obtained using a test video sequence of a real-time traffic scene show that the proposed method is effective.

Measurement and simulation of current-voltage relation in dye-sensitized solar cells with reduced graphene oxide at the counter electrodes

Sarker, Subrata,Kim, Dong Min Elsevier 2018 SOLAR ENERGY -PHOENIX ARIZONA THEN NEW YORK- Vol.176 No.-

<P><B>Abstract</B></P> <P>The performance of counter electrodes (CEs) dramatically affects the overall performance of dye-sensitized solar cells (DSSCs). To make the DSSCs perform with the fullest capacity of their photoelectrodes (PEs), the CEs must efficiently regenerate electrolyte and conduct electron. Thus, characterizing CEs and finding its essential features, which affect the photovoltaic performance of DSSCs, are of great importance for developing new efficient and low-cost CEs of DSSCs. Here, we report on the development of two different rGO electrodes for CEs of DSSCs by screen printing a viscous rGO paste on FTO substrates and comparison of the rGO electrodes with a thermally deposited Pt electrode. Moreover, we explain the photovoltaic performance of the DSSCs with an analytical model that resembles a diode model of DSSCs with a series resistance (<I>R</I> <SUB>s</SUB>) comprising all the series resistive elements including a potential dependent charge transfer resistance (<I>R</I> <SUB>ct</SUB>) at the CE. The model parameters were extracted from a <I>j-V</I> and EIS data of the DSSCs. The model calculation suggests that <I>R</I> <SUB>ct</SUB> should be as low as possible and the higher the catalytic activity, the higher the fill-factor; however, the higher catalytic activity comes with an adverse effect to the current density of the cells. Thus, developing materials for CEs with a smaller <I>R</I> <SUB>ct</SUB> without affecting the performance of the PEs is the key to develop high-efficiency Pt-free DSSCs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Counter electrode (CE) is one of the key components of dye-sensitized solar cells (DSSCs). </LI> <LI> Reduced graphene oxide (rGO) may act as an electrocatalyst material at the CEs. </LI> <LI> An analytical model is developed to calculate the photovoltaic performance of DSSCs. </LI> <LI> The model relates the performance of CE to the photovoltaic performance of DSSCs. </LI> <LI> The catalytic activity of rGO increases with thickness with a cost of decreased photocurrent. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Growth Promotion of Pavlova viridis by Bacteria Isolated from the Microalga

Sarker Anowarul Kabir Ahamed(사커 아노와룰 아하메드),Jin-Joo Kim(김진주),Tae-O Choi(최태오),Tae-Jin Choi(최태진) 한국생명과학회 2015 생명과학회지 Vol.25 No.5

해양 미세조류인 파블로바 비리디스는 빨리 자라며, DHA, EPA와 같은 해양생물을 키우는데 필수적인 영양요소를 축적하는 능력을 가지고 있어 어류와 새우류 치어 사육에 이용되어 왔다. 본 연구에서는 파블로바 비리디스와 이 미세조류의 표면에 붙어서는 세균과의 공생적 상호작용을 연구하였다. 무균의 파블로바 비리디스 균주는 항생제 혼합액을 포함하는 액체배지에 반복 배양함으로써 얻어졌다. 무균상태는 항생제를 포함하지 않는 배지에 3번 계대 배양한 후 확인하였다. 무균상태의 조류는 이 조류로부터 분리되었으며, 임의로 I1?I5로 명명한 세균과 혼합배양하면서 조류의 성장 촉진 효과를 조사하였다. 모든 세균이 파블로바 비리디스의 생장을 촉진하였으며, 그 중 I3로 명명한 세균이 5가지 세균 중 가장 효과가 좋았다. 혼합배양 상태에서 파블로바 비리디스의 세포 수는 대조구에 비하여 유의하게 많았다. I3의 16S rRNA 유전자에 대한 염기서열 분석 결과 시트로박터 종의 그것과 97%의 염기서열 상동성을 보였다. I3을 파블로바 비리디스와 혼합배양할 경우 I3의 성장도 유의하게 증가하였으며, 이것은 조류와 그 표면에 부착하여 살아가는 세균들 사이에 공생관계가 존재한다는 것을 제시한다. 미세조류와 세균과의 공생관계는 전자현미경적 관찰을 이용하여 확인하였다. The marine microalga Pavlova viridis can grow fast and has the ability to accumulate essential nutrients for culturing marine animals, such as EPA and DHA, and it has been used as food for raring larval fish and prawn. The symbiotic relationship between the flagellate microalga Pavlova viridis and its associated bacteria was investigated. An axenic culture of P. viridis was obtained by repeated treatment of the microalga with an antibiotic cocktail. The axenic status was confirmed after sub-culturing three times in a sterile f/2 medium without an antibiotic. The axenic alga was then co-inoculated with five bacteria, arbitrarily designated as I1?I5, isolated from the alga to test the growth promotion of the algae. All bacterial strains promoted the growth of P. viridis, and bacterial isolate I3 was the most effective among the five bacteria tested. The cell number of P. viridis in the co-culture with I3 was significantly higher than that of the control culture. A sequence analysis of the 16S rRNA gene isolated from I3 revealed a 97% nucleotide sequence similarity to that of Citrobacter sp. The growth of strain I3 was also significantly enhanced by co-culturing with P. viridis, indicating a symbiotic relationship between the microalga and its associated bacterium. The association between the microalga and bacterium was confirmed by scanning electron microscopy.

Nitrogen-doped porous carbon from ionic liquid@Al-metal-organic framework: A prominent adsorbent for purification of both aqueous and non-aqueous solutions

Sarker, Mithun,An, Hyung Jun,Yoo, Dong Kyu,Jhung, Sung Hwa Elsevier 2018 Chemical engineering journal Vol.338 No.-

<P><B>Abstract</B></P> <P>Nitrogen-doped porous carbons were derived through direct carbonization of ionic liquid (IL)-loaded Al-based metal-organic frameworks (MOFs, or porous coordination polymers) called AlPCP (IL@AlPCP), where IL was added to increase nitrogen contents of derived carbons. Porous carbons derived from IL@AlPCP and pristine AlPCP (called CDIL@AlPCP and CDAlPCP, respectively) were characterized using various techniques and utilized in liquid-phase adsorptions for both aqueous and non-aqueous media to realize their potential application in water and fuel purifications. The adsorptive performance of CDIL@AlPCP was remarkable for the removal of several pharmaceutical and personal care products from water. For example, the adsorption capacity of CDIL@AlPCP was thus far found to be the highest for para-chloro-meta-xylenol (PCMX) as compared with any reported adsorbent (including CDAlPCP and AC). Moreover, CDIL@AlPCP was also very effective for triclosan and acetaminophen adsorptions. Similarly, the efficiency of CDIL@AlPCP for adsorptive desulfurization and denitrogenation of the model fuel was also noticeable. The remarkable adsorption efficiency of CDIL@AlPCP for both aqueous and non-aqueous phases was explained in terms of mainly H-bonding. The direction of H-bonding can also be defined (for example, PCMX contributed as an H-donor, and ample N and O species of carbon materials contributed as an H-acceptor). Moreover, CDIL@AlPCP can be regenerated through simple ethanol washing and can be reused several times. Therefore, CDIL@AlPCP is recommended as a promising adsorbent for purification of both aqueous and non-aqueous solutions.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Nitrogen doped mesoporous carbon was obtained by pyrolysis of ionic liquid@AlPCP. </LI> <LI> The mesoporous carbon showed remarkable adsorption for water and fuel purification. </LI> <LI> H-bonding was a probable mechanism for various adsorptive purifications. </LI> <LI> The adsorbates and carbons behaved mainly as H-donor and -acceptor, respectively. </LI> <LI> CDIL@AlCP was a remarkable adsorbent based on adsorption capacity/reusability. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Testicular and epididymal ultrasonography for the assessment of semen quality in the indigenous ram

Sarker Suchana,Zohara Begum Fatema,Azizunnesa,Islam Md. Faruk,Bari Farida Yeasmin 사단법인 한국동물생명공학회 2021 한국동물생명공학회지 Vol.36 No.4

The aims of this study were to measure the ultrasonographic biometry of genitalia of the indigenous rams and observe the relationship of biometry on semen parameters. The epididymal volume was significantly reduced (p < 0.01) after semen collection compared with before collection for both left and right part in all rams. The cumulative results showed that although there was no significant difference in length, width and volume of epididymis between before and after semen collection, however the values were lower after collection. The epididymal length was significantly correlated with epididymal volume (p < 0.01), semen motility (p < 0.05) and semen morphology (p < 0.01). Epididymal width was only significantly correlated with epididymal volume (p < 0.01) not with the semen parameters. Epididymal volume had a significant correlation only with semen morphology (p < 0.01).The scrotal circumference had the significant correlation with semen density, mass activity, concentration and motility (p < 0.01). The epididymis had the similar or slightly increased echogenicity as compared to the normal testis. During whole study, some white spots were found on testis which did not affect the semen quantity and quality. Significant variation was observed only for semen concentration and motility among the rams (p < 0.05). The overall normal morphology was 90.5 ± 4.6% with highest percentage of coiled tail abnormalities.

Prognostic Implications of the SUVmax of Primary Tumors and Metastatic Lymph Node Measured by 18F-FDG PET in Patients With Uterine Cervical Cancer: A Meta-analysis

Sarker, Azmal,Im, Hyung-Jun,Cheon, Gi Jeong,Chung, Hyun Hoon,Kang, Keon Wook,Chung, June-Key,Kim, E. Edmund,Lee, Dong Soo Wolters Kluwer Health, Inc. All rights reserved. 2016 Clinical nuclear medicine Vol.41 No.1

<P>Purpose We conducted a meta-analysis to evaluate the prognostic value of the SUVmax measured in pretreatment primary lesions and metastatic lymph nodes (LNs) on F-18-FDG PET scans in patients with uterine cervical cancer. Methods A systematic search of EMBASE and MEDLINE was performed using the keywords positron emission tomography (PET), uterine cervical cancer, and prognosis. Event-free survival and overall survival were evaluated as outcomes. The impact of SUVmax on survival was measured by the effect size of the hazard ratio (HR). Results Fourteen eligible studies including 1150 patients were analyzed. Patients with a high primary SUVmax showed a worse prognosis, with an HR of 2.66 (95% confidence interval [CI], 1.90-3.74; P < 0.00001) for adverse events and an HR of 2.45 (95% CI, 1.74-3.45; P < 0.00001) for death. Patients with high SUVmax in metastatic pelvic LN (PLN) showed a worse prognosis, with an HR of 2.92 (95% CI, 1.94-4.39; P < 0.00001) for adverse events and an HR of 2.66 (95% CI, 1.60-4.43; P = 0.0002) for SUVmax in PLN for death. In addition, high SUVmax in metastatic para-aortic LN was associated with a worse prognosis, with an HR of 4.41 (95% CI, 2.32-8.38; P < 0.00001) for death. Conclusions Patients with uterine cervical cancer and a high SUVmax primary lesion, PLN, or para-aortic LN are at higher risk of adverse events or death.</P>

[64Cu]Cu-Albumin Clearance Imaging to Evaluate Lymphatic Efflux of Cerebrospinal Space Fluid in Mouse Model

Sarker Azmal,서민석,최유리,박지용,권석준,김현,이은지,서혜연,이윤상,이동수 대한핵의학회 2022 핵의학 분자영상 Vol.56 No.3

Purpose Clearance of brain waste in the cerebrospinal fluid (CSF) through the meningeal lymphatic vessels (mLV) has been evaluated mostly through the fluorescent imaging which has inherent limitations in the context of animal physiology and clinical translatability. The study aimed to establish molecular imaging for the evaluation of mLV clearance function. Methods Radionuclide imaging after intrathecal (IT) injection was acquired in C57BL/6 mice of 2–9months. The distribution of [99mTc]Tc-diethylenetriamine pentaacetate (DTPA) and [64Cu]Cu-human serum albumin (HSA) was comparatively evaluated. Evans Blue and [64Cu]Cu-HSA were used to evaluate the distribution of tracer under various speed and volume conditions. Results [99mTc]Tc-DTPA is not a suitable tracer for evaluation of CSF clearance via mLV as no cervical lymph node uptake was observed while it was cleared from the body. A total volume of 3 to 9 μL at an infusion rate of 300 to 500 nL/min was not sufficient for the tracer to reach the cranial subarachnoid space and clear throughout the mLV. As a result, whole-body positron emission tomography imaging using [64Cu]Cu-HSA at 700 nL/min, to deliver 6 μL of injected volume, was set for characterization of the CSF to mLV clearance. Through this protocol, the mean terminal CSF clearance half-life was measured to be 123.6 min (range 117.0–135.0) in normal mice. Conclusions We established molecular imaging to evaluate CSF drainage through mLV using [64Cu]Cu-HSA. This imaging method is expected to be extended in animal models of dysfunctional meningeal lymphatic clearance and translational research for disease-modifying therapeutic approaches.