INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH最新文献

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On electromagnetic precursors to the Hokkaido earthquake in September, 2018 and consideration of lithosphere-atmosphere-ionosphere coupling 2018年9月北海道地震电磁前兆及岩石圈-大气-电离层耦合的考虑
INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH Pub Date : 2019-08-22 DOI: 10.33665/ijear.2019.v06i01.003
M. Hayakawa, A. Rozhnoi, M. Solovieva, Shih-Sian Yang
{"title":"On electromagnetic precursors to the Hokkaido earthquake in September, 2018 and consideration of lithosphere-atmosphere-ionosphere coupling","authors":"M. Hayakawa, A. Rozhnoi, M. Solovieva, Shih-Sian Yang","doi":"10.33665/ijear.2019.v06i01.003","DOIUrl":"https://doi.org/10.33665/ijear.2019.v06i01.003","url":null,"abstract":"Electromagnetic precursors have been investigated for a recent relatively large earthquake (EQ) with magnitude M=6.7 occurred in the Hokkaido Island, Japan on 5 September (UT), 2018 on the basis of coordinated data on the lower ionospheric perturbation with subionospheric VLF/LF propagation anomalies monitored in Japan and in Russia, on the upper F region anomaly with GIM (global ionosphere map) TEC (Total Electron Content) and on the stratospheric behavior with the use of ERA5 temperature profile data. It is found that there were observed the clearest VLF/LF propagation anomalies indicative of seismogenic lower ionospheric perturbations above the EQ epicenter on 4 and 5 September before the EQ and 6 September even after it because this period was geomagnetically quiet. As for the F region, an anomaly in TEC over the EQ epicenter appeared only on 5 September, but it is quite uncertain whether this anomaly is related to either a pre-EQ effect or a geomagnetic storm effect. Then, we have tried to find if there were some seismo-related AGW (atmospheric gravity wave) activities in the stratosphere, but though we have found a lot of anomalies, they are highly likely to be associated with the activities by convective weather systems. Even though we have recently identified the first convincing direct evidence on the Atmospheric oscillation hypothesis in the lithosphere-atmosphere-ionosphere coupling (LAIC) mechanism for the 2016 Kumamoto EQ [Yang et al., 2019], this paper aimed initially to obtain further evidence on this channel. However, the above experimental findings may provide a negative result in this direction; that is, this Atmospheric oscillation channel is unlikely to be in operation for the present 2018 Hokkaido EQ, suggesting other channels in the LAIC effect. So we have made extensive discussions on this LAIC mechanism for this Hokkaido EQ with special reference to the 2016 Kumamoto EQ and the 2011 Tohoku EQ. https://doi.org/10.33665/IJEAR.2019.v06i01.003 International Journal of Electronics and Applied Research (IJEAR) vol. 6, issue 1, June 2019 Online (http://eses.net.in/online_journal.html) ISSN 2395-0064 _____________________________________________________________________________________ Copyright @ESES IJEAR","PeriodicalId":249119,"journal":{"name":"INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH","volume":"281 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121996313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Wind profiling features and atmospheric dynamics: A few first observations from ST Radar of Gauhati University 风廓线特征和大气动力学:高哈蒂大学ST雷达的一些初步观测
INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH Pub Date : 2019-08-22 DOI: 10.33665/ijear.2019.v06i02.004
M. Devi, S. Patgiri, A. Medhi, S. Das, A. Barbara, R. Mahato, S. Shaw
{"title":"Wind profiling features and atmospheric dynamics: A few first observations from ST Radar of Gauhati University","authors":"M. Devi, S. Patgiri, A. Medhi, S. Das, A. Barbara, R. Mahato, S. Shaw","doi":"10.33665/ijear.2019.v06i02.004","DOIUrl":"https://doi.org/10.33665/ijear.2019.v06i02.004","url":null,"abstract":"The windfeatures in fine spatio-temporal resolutions covering lower troposphere to beyond tropopause, are important inputs for understanding atmospheric dynamics associated with weather and climate. The extraction of information from such features requires complex analysis processes because of involvement of wide dynamical meteorology. Therefore, for study of this type, it is essential to have special atmospheric probing set up along with embedded state of art signal analysis tools, where Stratospheric Tropospheric (ST) Radar proves to be one of the most ideal facility that can provide high resolution wind profiling data covering this defined range. The paper thus attempts to understand the physics and dynamics of the atmosphere associated with complex weather environment of the North East part of India by analyzing wind profiling characters received from the ST Radar, installed at Gauhati University (26 ̊N, 91. ̊ E), that offers wind velocity as detailed as 0.1 m/s (in vertical mode) with altitude resolution of 150 m. Starting with the calibration of Radar derived wind parameters with Radiosonde and satellite observed data; the analysis here is directed to assess the reliability of wind speed and directions obtained from this setup. The special events like precipitation and thunder time modulations of wind components are also presented and possible system physics for development of such situations has been focused.","PeriodicalId":249119,"journal":{"name":"INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132332463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Observed Data Containing One Parameter and Chance Error: Probabilistic Evaluation of Parameter by Pythagorean Mean 包含一个参数和机会误差的观测数据:参数的毕达哥拉斯平均值的概率估计
INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH Pub Date : 2019-08-22 DOI: 10.33665/ijear.2019.v06i01.002
D. Chakrabarty
{"title":"Observed Data Containing One Parameter and Chance Error: Probabilistic Evaluation of Parameter by Pythagorean Mean","authors":"D. Chakrabarty","doi":"10.33665/ijear.2019.v06i01.002","DOIUrl":"https://doi.org/10.33665/ijear.2019.v06i01.002","url":null,"abstract":"Recently some methods have been developed for determining the appropriate value of the parameter from observed data containing the parameter itself and chance error since the existing statistical methods of estimation in such situation fail in finding out the appropriate value of the parameter. However, the methods are based on some probabilistic assumptions. Accordingly, the value of the parameter obtained by the methods is not deterministic but probabilistic i.e. one cannot be fully certain that the value of the parameter obtained is identical with its actual value. This paper is based on the evaluation of the probability that the value obtained is the actual value of the parameter and on one numerical application of the method in determining the central tendency of each of annual maximum and annual minimum of ambient air temperature at Guwahati.","PeriodicalId":249119,"journal":{"name":"INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114804048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 6
Arithmetic-Geometric Mean: Evaluation of Parameter from Observed Data Containing Itself and Random Error 算术-几何平均:从包含自身和随机误差的观测数据中评估参数
INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH Pub Date : 2019-08-22 DOI: 10.33665/ijear.2019.v06i02.003
D. Chakrabarty
{"title":"Arithmetic-Geometric Mean: Evaluation of Parameter from Observed Data Containing Itself and Random Error","authors":"D. Chakrabarty","doi":"10.33665/ijear.2019.v06i02.003","DOIUrl":"https://doi.org/10.33665/ijear.2019.v06i02.003","url":null,"abstract":"Recently some methods have been developed for determining the value of parameter from observed data containing a single parameter and random error since the existing statistical methods of estimation in such situation fail in finding out the appropriate value of the parameter. The methods, so developed, involve huge computational tasks. Moreover, a finite set of observed data may not yield the appropriate value of the parameter in many situations while the number of observations required in the methods may be too large for obtaining the appropriate value of the parameter. For these two limitations, one method for the same has been developed here which involves lesser computational tasks than those involved in the methods developed so far. Moreover, the method described here can be applicable in the case of finite set of data. This paper describes the derivation of the method and one numerical application of the method in determining the central tendency of each of annual maximum and annual minimum of surface air temperature at Guwahati.","PeriodicalId":249119,"journal":{"name":"INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128034551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 6
Local time, annual, latitude, and seasonal variations of total electron content over Japan 日本上空总电子含量的当地时间、年、纬度和季节变化
INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH Pub Date : 2019-08-22 DOI: 10.33665/ijear.2019.v06i02.002
K. Oyama, K. Noguch
{"title":"Local time, annual, latitude, and seasonal variations of total electron content over Japan","authors":"K. Oyama, K. Noguch","doi":"10.33665/ijear.2019.v06i02.002","DOIUrl":"https://doi.org/10.33665/ijear.2019.v06i02.002","url":null,"abstract":"Total Electron Content(TEC)data are being accumulated by using about 1000 GPS receivers under the coordination of Japan Geographical Survey Institute to monitor the movement of Japanese islands which experience frequent earthquake. General pictures of diurnal, seasonal, and annual variations of TEC at three receiving stations, Okinawa (25degrees N), Kokubunji (35degrees N), and Wakkanai (45 degrees N) have been obtained by using the data acquired in the period of January 2000 January 2004. Seasonal variation shows two peaks in March and September which start to appear clearly in Okinawa at 08 JST (Japan Standard Time) and disappears at 04 JST. The magnitude of the two peaks is nearly the same until 22 JST and the September peak starts to reduce the magnitude from 02 JST and disappears at 06 JST. Whilst at Kagoshima and Aomori, two peaks appear between 08 JST and 16 JST. After 16 JST the September peak starts decreasing and disappears at 18 JST, which is much earlier than at Okinawa. Daytime TEC in January in low latitude is nearly equal to the TEC in July. Daytime TEC increases as solar radio flux increases. This tendency is the smallest in summer. Nighttime TEC also shows a slight increase as the solar radio flux increases.","PeriodicalId":249119,"journal":{"name":"INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128990005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Possible relation of air ion density anomalies with earthquakes and the associated precursory ionospheric perturbations: An analysis in terms of criticality 空气离子密度异常与地震和相关的电离层前兆扰动的可能关系:从临界性角度的分析
INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH Pub Date : 2018-12-31 DOI: 10.33665/IJEAR.2018.V05I02.004
M. Hayakawa, S. Potirakis, Y. Saito
{"title":"Possible relation of air ion density anomalies with earthquakes and the associated precursory ionospheric perturbations: An analysis in terms of criticality","authors":"M. Hayakawa, S. Potirakis, Y. Saito","doi":"10.33665/IJEAR.2018.V05I02.004","DOIUrl":"https://doi.org/10.33665/IJEAR.2018.V05I02.004","url":null,"abstract":"The air ion density observed at Sendai during a period of 10/02/2013 to 30/04/2016 (more than 3 years) has been analyzed in terms of natural time critical analysis. It is then found that the air ions exhibit criticalities at some specific time periods, as a signature of pre-earthquake (EQ) fracturing process in the lithosphere. So it is likely to conclude that this criticality analysis enables us to associate the criticality in ion density to an EQ as a general tendency. The detection of air ions at a particular place suggests that those ions may be a precursor to an EQ (magnitude greater than 5.0) occurring within a radius of 200 km from the ion observatory. However, based on a comparison with the corresponding VLF/LF sub-ionospheric propagation data, we cannot say anything about a certain relationship of those air ions with the lower ionospheric perturbation as seen by VLF/LF, because the temporal scale of ions is medium-termed, but VLF/LF perturbation is short-termed, which makes it extremely difficult to correlate between the two.","PeriodicalId":249119,"journal":{"name":"INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121210378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
The effect of a compact ionosphere disturbance over the earthquake: A Focus on Schumann resonance 致密电离层扰动对地震的影响:以舒曼共振为焦点
INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH Pub Date : 2018-12-31 DOI: 10.33665/ijear.2018.v05i02.002
A. Nickolaenko, Y. Galuk, M. Hayakawa
{"title":"The effect of a compact ionosphere disturbance over the earthquake: A Focus on Schumann resonance","authors":"A. Nickolaenko, Y. Galuk, M. Hayakawa","doi":"10.33665/ijear.2018.v05i02.002","DOIUrl":"https://doi.org/10.33665/ijear.2018.v05i02.002","url":null,"abstract":"We model perturbations of vertical electric and horizontal magnetic fields of Schumann resonance by a localized seismogenic non-uniformity in the Earth–ionosphere cavity with simultaneous accounting for the day–night non-uniformity. The source and receiver are placed at the same meridian and the latitudes covering 22.5° N and 22.5° S. The propagation path is positioned at the night (60° E) or the dayside (120° E) of morning terminator. The localized nonuniformity moves either along or across the propagation path. The full wave solution is used in the form of Riccati equation for finding the propagation parameters. The spectral components of fields are computed with the 2D (two dimensional) telegraph equations. Numerical estimates were obtained of the impact of the localized ionosphere non-uniformity on the electric and magnetic field amplitudes at a set of Schumann resonance frequencies for various positions of disturbances relative to the propagation path. It is shown that the impact of compact nonuniformity grows with increasing frequency. Field modifications are of interference nature. The day–night asymmetry provides a minor impact, and one may neglect this non-uniformity. The model was applied to interpret observations with a point source in Southeast Asia, Africa, or in South America. The observer was positioned at the Moshiri observatory, Japan. The earthquake focus modifying the conductivity of mesosphere was located at Taiwan. Perturbations of amplitude spectra of Schumann resonance were computed and their similarity to the observations was demonstrated.","PeriodicalId":249119,"journal":{"name":"INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH","volume":"214 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121341967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 6
Finite Difference and Ratio Operations: Representation of Numerical Data on a Pair of Variables by a Polynomial Curve 有限差分和比值运算:用多项式曲线表示一对变量上的数值数据
INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH Pub Date : 2018-12-31 DOI: 10.33665/IJEAR.2018.V05I02.005
D. Chakrabarty
{"title":"Finite Difference and Ratio Operations: Representation of Numerical Data on a Pair of Variables by a Polynomial Curve","authors":"D. Chakrabarty","doi":"10.33665/IJEAR.2018.V05I02.005","DOIUrl":"https://doi.org/10.33665/IJEAR.2018.V05I02.005","url":null,"abstract":"The recently introduced approach to interpolation which consists of the representation of numerical data by a suitable polynomial curve and then to compute the value of the dependent variable from the curve corresponding to any given value of the independent variable leads to the necessity of a method/formula for representing a given set of numerical data on a pair of variables by a suitable polynomial curve. One method, in addition to the existing methods, has been developed for representing a set of numerical data on a pair of variables by a suitable polynomial curve. The method developed here, which is simpler than the earlier ones, is based on two numerical operations namely finite difference operation and ratio operation. This paper describes the development of the method with numerical example in order to show the application of the method to numerical data.","PeriodicalId":249119,"journal":{"name":"INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129302793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Phishing URL detection system based on URL features using SVM 基于URL特征的支持向量机网络钓鱼URL检测系统
INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH Pub Date : 2018-12-31 DOI: 10.33665/ijear.2018.v05i02.003
Bireswar Banik, A. Sarma
{"title":"Phishing URL detection system based on URL features using SVM","authors":"Bireswar Banik, A. Sarma","doi":"10.33665/ijear.2018.v05i02.003","DOIUrl":"https://doi.org/10.33665/ijear.2018.v05i02.003","url":null,"abstract":"Phishing activities on the Internet are increasing day by day. It is an illicit attempt made by the attackers to steal personal information such as bank account details, login id, passwords etc. Many of the researchers proposed to detect phishing URLs by extracting features from the content of the web pages. But lots of time and space is required for this. This paper presents an approach to detect phishing URLs in an efficient way based on URL features only. For detecting the phishing URLs SVM classifier is used. The performances are evaluated for different size of datasets using different number of features. The results are compared with other machine learning classification techniques. The proposed system is able to detect phishing websites using URL features only with accuracy of 96.35%.","PeriodicalId":249119,"journal":{"name":"INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122063023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 10
The response of global seismicity to solar flares of September, 2017 2017年9月全球地震活动对太阳耀斑的响应
INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH Pub Date : 2018-12-31 DOI: 10.33665/IJEAR.2018.V05I02.001
Y. Ruzhin, V. Novikov
{"title":"The response of global seismicity to solar flares of September, 2017","authors":"Y. Ruzhin, V. Novikov","doi":"10.33665/IJEAR.2018.V05I02.001","DOIUrl":"https://doi.org/10.33665/IJEAR.2018.V05I02.001","url":null,"abstract":"Results of an analysis of interrelation between powerful solar flares of September, 2017 and global seismic activity are presented. It was found that during the period of solar flares and one week after it the number of earthquakes rises by up to 100%. We attribute the obtained results to earthquake triggering effects of solar flares. A possibility of electric/electromagnetic triggering of earthquakes due to space weather disturbances is supported by results of field and laboratory experiments, where earthquakes (both natural and laboratory) were initiated by injection of electrical current into the Earth crust or simulated seismogenic fault. For the case of man-made electric earthquake triggering the current density at the depth of earthquake sources is comparable with estimations of a density of telluric currents induced by variation of space weather conditions due to solar flares.","PeriodicalId":249119,"journal":{"name":"INTERNATIONAL JOURNAL OF ELECTRONICS AND APPLIED RESEARCH","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128040560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
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