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Cybersecurity: Identifying the Vulnerability Intensity Function (VIF) and Vulnerability Index Indicator (VII) of a Computer Operating System

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Journal of Information Security 2022年第4期13卷 337-362页

作者： ranju Karki Chris P. Tsokos Department of Mathematics and Statistics University of South Florida Tampa USA

The objective of the present study is to define two important aspects of the computer operating system concerning the number of its vulnerabilities behavior. We identify the Vulnerability Intensity Function (VIF), and the Vulnerability Index Indicator (VII) of a computer operating network. Both of these functions, VIF and VII are entities of the stochastic process that we have identified, which characterizes the probabilistic behavior of the number of vulnerabilities of a computer operating network. The VIF identifies the rate at which the number of vulnerabilities changes with respect to time. The VII is an important index indicator that conveys the following information about the number of vulnerabilities of Desktop Operating Systems: the numbers are increasing, decreasing, or remaining the same at a particular time of interest. This decision type of index indicator is crucial in every strategic planning and decision-making. The proposed VIF and VII illustrate their importance by using real data for Microsoft Windows Operating Systems 10, 8, 7, and Apple MacOS. The results of the actual data attest to the importance of VIF and VII in the cybersecurity problem we are currently facing.

关键词： Cybersecurity Operating Systems Vulnerabilities Stochastic Process Vulnerability Intensity Function Vulnerability Index Indicator

Methane Gas Sensor Based on Microstructured Highly Sensitive Hybrid Porous Core Photonic Crystal Fiber

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Journal of Sensor Technology 2019年第1期9卷 12-26页

作者： Md. ranju Sardar Mohammad Faisal Department of Electrical & Electronic Engineering (EEE) Bangladesh University of Engineering & Technology (BUET) Dhaka-1000 Bangladesh

We have demonstrated and analyzed the methane gas sensor based on octagonal cladding and hexagonal hybrid porous core photonic crystal fiber (HPC-PCF) for gas detection purpose. The proposed design of HPC-PCF has been numerically investigated by COMSOL Multiphysics software through utilizing the full vectorial finite element method (FEM). The optical characteristics of HPC-PCF as well as confinement loss, relative sensitivity and refractive index, effective area, nonlinearity and numerical aperture are optimized properly by changing the geometrical parameters as well as air filling ratio, air hole diameter, pitch constant of cladding and porosity of the core. In this simulation work, we have achieved optimum relative sensitivity of 21.2%, and confinement loss of 0.000025 dB/m at 3 μm pitch, 0.7 air filling ratio of the cladding and 29% porosity of the core for 3.5 μm absorption wavelength of CH4 gas. This proposed design of HPC-PCF will keep exclusive contribution for detecting the CH4 gas accurately.

关键词： HPC-PCF Relative Sensitivity Confinement Loss Porosity CH4 Gas and Gas Sensor

Loss of disabled-2 expression is an early event in esophageal squamous tumorigenesis

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World Journal of Gastroenterology 2006年第37期12卷 6041-6045页

作者： Kumar Anupam Chatopadhyay Tusharkant Siddhartha Datta Gupta Ralhan ranju Department of Biochemistry All India Institute of Medical Sciences Ansari Nagar New Delhi 110029 India Department of GI Surgery All India Institute of Medical Sciences Ansari Nagar New Delhi 110029 India Department of Pathology All India Institute of Medical Sciences Ansari Nagar New Delhi 110029 India

AIM: Disabled-2 (DAB2) is a candidate tumor-suppressor gene identified in ovarian cancer that negatively influences mitogenic signal transduction of growth factors and blocks ras activity. In a recent study, we observed down-regulation of DAB2 transcripts in ESCCs using cDNA microarrays. In the present study, we aimed to determine the clinical significance of loss of DAB2 protein in esophageal tumorigenesis, hypothesizing that DAB2 promoter hypermethylation-mediated gene silencing may account for loss of the protein. METHODS: DAB2 expression was analyzed by immunohistochemistry in 50 primary esophageal squamous cell carcinomas (ESCCs), 30 distinct hyperplasia, 15 dysplasia and 10 non-malignant esophageal tissues. To determine whether promoter hypermethylation contributes to loss of DAB2 expression in ESCCs, methylation status of DAB2 promoter was analyzed in DAB2 immuno-negative tumors using methylation-specifi c PCR. RESULTS: Loss of DAB2 protein was observed in 5/30 (17%) hyperplasia, 10/15 (67%) dysplasia and 34/50 (68%) ESCCs. Significant loss of DAB2 protein was observed from esophageal normal mucosa to hyperplasia, dysplasia and invasive cancer (Ptrend < 0.001). Promoter hypermethylation of DAB2 was observed in 2 of 10 (20%) DAB2 immuno-negative ESCCs. CONCLUSION: Loss of DAB2 protein expression occurs in early pre-neoplastic stages of development of esophageal cancer and is sustained down the tumorigenic pathway. Infrequent DAB2 promoter methylation in ESCCs suggests that epigenetic genesilencing is only one of the mechanisms causing loss of DAB2 expression in ESCCs.

关键词： Disabled-2 DOC-2 Esophageal cancer Promoter hypermethylation Dysplasia

Analysis of Rate One Quasi-Orthogonal Space-Time Block Coding over Rayleigh Fading Channel

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International Journal of Communications, Network and System Sciences 2014年第6期7卷 196-202页

作者： Md. Abdullah Al Amin ranju Ragib Shakil Rafi Electronics & Communication Engineering Khulna University Khulna Bangladesh

Full-rate is very important in any data transmission coding. For transmitting data at low bit rate than full-rate code, higher modulation scheme is required. But it is impossible to design full rate orthogonal designs with complex constellation for more than two transmit antennas. Only Alamouti code provides full-rate for two transmit antennas. In this paper, Bit Error Rate (BER) is calculated for Quasi-Orthogonal Space-time Block Coding (QOSTBC). Here we work with Rayleigh fading channel. We consider the codes which decodes pairs of symbols instead of simple separate decoding like Orthogonal Space-Time Block Coding. In Quasi-Orthogonal Space-time Block Code full-rate is achieved but full-diversity is sacrificed. Diversity is the most important techniques for providing reliable communication over fading channels. One of the diversity techniques that uses multiple transmit and/or receive antennas is space diversity. Multiple antenna technique provides a space diversity to struggle with the fading without necessarily sacrificing bandwidth resources, so the excellent solutions of removing the fading of the channel for broadband wireless communications is using space diversity. Then, with the constellation rotation of the symbol, rotated version of Quasi-Orthogonal Space-Time Block Code is generated. It provides full diversity. We simulate BER for QOSTBC, rotated QOSTBC, orthogonal STBC and for uncoded system. The simulation result shows that QOSTBC and rotated QOSTBC perform better than other systems. It shows that QOSTBC provides a full transmission rate but that rotated QOSTBC provides the full rate with the full diversity.

关键词： Orthogonal Space-Time Block Coding Quasi-Orthogonal Space-Time Block Coding Rayleigh Fading Rotated Quasi-Orthogonal Space-Time Block Coding

siRNA-mediated downregulation of TC21 sensitizes esophageal cancer cells to cisplatin

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World Journal of Gastroenterology 2012年第31期18卷 4127-4135页

作者： Md.Raghibul Hasan Shyam Singh Chauhan Rinu Sharma ranju Ralhan Department of Biochemistry All India Institute of Medical SciencesNew Delhi 110029India Department of Biotechnology School of BiotechnologyGuru Gobind Singh Indraprastha UniversityNew Delhi 110075India Department of Otolaryngology-Head and Neck Surgery Joseph and Mildred Sonshine Family Centre for Head and Neck DiseasesMount Sinai HospitalTorontoON M5G 1X5Canada Department of Pathology and Laboratory Medicine Alex Simona Shnaider Laboratory for Molecular OncologyMount Sinai HospitalTorontoON M5G 1X5Canada

AIM： To determine the functional significance of TC21 in esophageal squamous cell carcinoma （ESCC）. METHODS： TC21 siRNA transfection was carried out using Hyperfectamine to knock down TC21, and tran- scripts were analyzed by reverse transcription-poly- merase chain reaction and protein by Western *** demonstrated the effect of TC21 downregulation of cell signaling in esophageal cancer cells by assess- ing the phosphorylation status of its downstream tar- gets, phosphoinositide 3-kinase （PI3K）, phosphatase and tensin homolog （PTEN）, protein kinase B （pAl〈t）, nuclear factor-KB （NF-~B） and cyclinD1 using specific antibodies. Cell survival analysis after cisplatin treat- ment was carried out by cell viability assay and cell cycle analysis using flow cytometry. RESULTS： TC21 knockdown in human ESCC cell line TEl3 cells, showed only a marginal increase （14.2%） in cell death compared with control cells. The expres- sions of the signaling proteins PI3K and pAkt, transcrip- tion factor NF-KB, and cell cycle protein cyclin D1 were markedly decreased in response to TC21 downregula- tion, whereas the level of pPTEN, an antagonist of PI3K, was increased. In addition, we evaluated the potential of TC21 as a putative target for sensitizing ESCC cells to the chemotherapeutic agent cisplatin. Increased cell death （38.4%） was observed in cells treated with cis- platin after TC21 knockdown compared with cells which were treated with cisplatin alone （20% cell death）. CONCLUSION： Results suggest that TC21 mediates its effects via the PI3K-Akt pathway, NF-KB and cyclin D1, and enhances chemoresistance in esophageal cancer cells.

关键词： TC21 Esophageal squamous cell carci-noma siRNA Cisplatin Chemosensitivity

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羽毛羽绒微波消解方法的研究

现代纺织技术 2016年第6期24卷 10-12页

作者：蒙冉菊嘉兴职业技术学院纺织与艺术设计分院浙江嘉兴314036

运用微波消解技术对羽毛羽绒样品消解,探究了消解试剂的种类和比例,样品粉碎的程度,消解前放置的时间,消解时间、消解功率和压力等微波消解的工艺条件。综合节省资源、减小污染、提高效率以及消解效果良好的要求,可确立较佳的消解工艺... 详细信息

运用微波消解技术对羽毛羽绒样品消解,探究了消解试剂的种类和比例,样品粉碎的程度,消解前放置的时间,消解时间、消解功率和压力等微波消解的工艺条件。综合节省资源、减小污染、提高效率以及消解效果良好的要求,可确立较佳的消解工艺。结果表明:将羽毛羽绒样品粉碎至5mm以下,在室温下于4mLHNO_3和1mLH_2O_2混合试剂中浸泡2h后进行微波消解,消解功率采用梯度升高的模式,消解总时间取15min,可获得较好的消解效果。

关键词：微波消解技术羽毛羽绒消解工艺

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辽宁省宽甸县东挂牌岭硼矿深部找矿前景探析

化工矿产地质 2010年第3期32卷 149-153页

作者：贾玉国李然菊辽宁省化工地质勘查院辽宁锦州121000

位于辽宁省宽甸县大西岔乡的东挂牌岭硼矿,处于杨木杆复式向斜构造南翼,含硼层位赋存于里尔峪组中下部,呈层状、似层状展布。地表赋矿层在走向和倾向上都具有膨缩现象。通过与邻近庙沟矿区的矿体特征、构造等成矿条件综合对比,二者均发... 详细信息

位于辽宁省宽甸县大西岔乡的东挂牌岭硼矿,处于杨木杆复式向斜构造南翼,含硼层位赋存于里尔峪组中下部,呈层状、似层状展布。地表赋矿层在走向和倾向上都具有膨缩现象。通过与邻近庙沟矿区的矿体特征、构造等成矿条件综合对比,二者均发育有大范围含矿层,且含矿层规模较大,同时严格受蛇纹石化镁橄岩层控制,为层控矿床;地表蚀变均较强烈,蛇纹石化较普遍。普遍存在较大规模的北北东向逆断层,赋矿层受此构造影响,普遍向深部侧伏等方面非常相似。通过地表及浅部钻孔(350m以上)控制,认为矿体具有一定的厚度和品位,在走向、倾向上延伸均较好,在倾向上有增厚的趋势。故推测东挂牌岭西区深部资源前景巨大,有望通过进一步工作,取得找矿突破。

关键词：混合岩化蛇纹石化赋矿层硼矿资源前景

羽绒制品的填充密度和分割空间与保暖性关系的研究

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现代纺织技术 2013年第3期21卷 21-24页

作者：高慧英蒙冉菊嘉兴职业技术学院纺织与艺术设计分院浙江嘉兴313000

为了在相同的羽绒填充量条件下,更好地提高羽绒制品的保暖性能,模拟实际的羽绒制品,分别制备了不同含绒量、不同填充密度、不同分割空间的羽绒制品,采用平板式织物保暖仪和织物厚度仪测试了样品的填充密度和保暖率,研究了羽绒制品的填... 详细信息

为了在相同的羽绒填充量条件下,更好地提高羽绒制品的保暖性能,模拟实际的羽绒制品,分别制备了不同含绒量、不同填充密度、不同分割空间的羽绒制品,采用平板式织物保暖仪和织物厚度仪测试了样品的填充密度和保暖率,研究了羽绒制品的填充密度、空间分割与保暖性之间的关系。结果显示,羽绒制品的保暖性能与填充密度和分割空间有很大的关系,制品的保暖性能随填充密度的增加而提高,当填充密度达到一定值后,保暖性能处于恒定;在饱和填充密度附近,含绒率对保暖性能的影响不大,空间分割过大或过小,均影响羽绒的保暖性能,因此,适宜的填充密度和空间分割有利于提高羽绒制品的保暖性,控制和降低产品生产成本。

关键词：羽绒制品保暖性填充密度分割空间

静电纺丝工艺参数对SS/PEO纳米纤维形貌及直径的影响

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丝绸 2018年第12期55卷 37-42页

作者：蒙冉菊王铁军翁浦莹陈文高慧英嘉兴职业技术学院纺织与艺术设计学院浙江嘉兴314036 山东华平新材料科技有限公司山东滨州256200

以质量分数为20%丝胶蛋白(SS)水溶液、6%聚环氧乙烷(PEO)水溶液为原料配制SS/PEO纺丝液,采用静电纺丝技术制备SS/PEO纳米纤维。探讨两种溶液混合比例及搅拌时间、纺丝电压、纺丝距离、纺丝速度等工艺参数对SS/PEO纳米纤维形貌及直径的... 详细信息

以质量分数为20%丝胶蛋白(SS)水溶液、6%聚环氧乙烷(PEO)水溶液为原料配制SS/PEO纺丝液,采用静电纺丝技术制备SS/PEO纳米纤维。探讨两种溶液混合比例及搅拌时间、纺丝电压、纺丝距离、纺丝速度等工艺参数对SS/PEO纳米纤维形貌及直径的影响。实验结果表明:当SS、PEO溶液的质量混合比为1︰2、搅拌时间为3 h、纺丝电压为25 kV、纺丝距离为20 cm、纺丝速度为0. 001 mL/s时,纺丝效果好,且获得形态好、直径细且分布均匀的SS/PEO纳米纤维。

关键词： SS/PEO纳米纤维静电纺丝纤维形貌纤维直径工艺参数