Estimation of the 2D crustal velocity structure in the Hidaka and Iburi Subprefectures, Hokkaido, Japan     

Ismail Husain Fathi  Kaoru Miyashita 《Arabian Journal of Geosciences》2009,2(3):235-239

Applying the iterative shooting/bisection technique for rapid forward modeling to the seismic explosion data, we could refine the crustal velocity structure model of the western part of the Hidaka collision zone, Hokkaido, Japan. We used only the precise P-wave first arrival data obtained by the Research Group for Explosion Seismology, which set up a 113.4-km-long profile in August 2000 along with 327 observation points and four shot points with TNT charges from 100 to 300 kg. We could estimate a two-dimensional inhomogeneous crustal velocity structure model with a velocity decrease in the eastern direction at a depth of 15.7 km, several portions of velocity reversals with depth and a low velocity anomaly proposed in previous studies. The root-mean-square of travel-time residuals was improved from 0.398 s for the previous structure model to 0.176 s for the present model with a reduction of 55.8%.  相似文献   

Vibration analysis of damaged and undamaged steel structure systems: cantilever column and frame     

Khan  Muhammad Abuzar  Akhtar  Kareem  Ahmad  Naveed  Shah  Feroz  Khattak  Naeem 《地震工程与工程振动(英文版)》2020,19(3):725-737

This paper presents the experimental and numerical studies conducted on a steel column and a steel frame structure using free vibration analysis. The effects of damages on structures were investigated, which were simulated by introducing multiple cracks at different locations in the experimental and numerical models. The acceleration responses of the test models, were recorded through an accelerometer, and were used to calibrate the numerical models developed in finite element based software. Modal frequencies of damaged and undamaged structures were compared and analyzed, to derive relationships for damaged and undamaged structures' frequencies in terms of crack depth. It was found that, due to the presence of cracks, the mechanical properties of a structure changes, whereby, the modal frequencies decrease. An approximately linear trend was observed for the frequency decrease with the increase in crack depth, which was also confirmed by the numerical models. The derived relationships were extended to further develop a mechanics-based damage scale for steel structures, to help facilitate structural health monitoring and screening of vulnerable structures.  相似文献   

Trace Metals Accumulation and Antioxidants Profiling in Two Maize Genotypes Against Sewage and Textile Wastewater Treatment     

Zoya Zafar  Javaid Akhtar  Muhammad Amjad  Muhammad Anwar‐ul‐Haq  Zulfiqar Ahmed Saqib 《洁净——土壤、空气、水》2019,47(7)

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Ion acoustic double layers in the presence of positrons beam and q-nonextensive velocity distributed electrons     

S. Ali Shan  A. Mushtaq  N. Akhtar 《Astrophysics and Space Science》2013,348(2):501-510

Linear and nonlinear studies are presented for an electron-ion plasma system which is being energized with an external beam of positrons. The electrons are assumed to follow the q-nonextensive velocity distribution. The growth rates of instability due to positron beam are analyzed numerically. The compressive and rarefactive double layers are studied in the system and it is found that by varying the entropic index parameter q, positron beam speed v _po and concentration of positrons p, the dynamics of nonlinear profile is changing quite effectively. The relevance of the work regarding to astrophysical space plasma is pointed out.  相似文献   

A conceptual and analytical framework for understanding the spatial effects on political actions in a new world order     

Mohamed Ismail Siddiqi 《GeoJournal》1995,37(1):161-169

All creations, except mankind, on this Universe are well organized under a natural universal system. They struggle for their survival within the territorial limits of their making. They do not have special barriers between, particularly similar to International Boundaries of Mankind. They even move from one physical region to another if the basic requirements, necessary for their survival are exhausted. Mankind is recognized as supreme to all creations, but diversity of their character, behavior, suspicious, and indifferent political ideology with uncomfortable mask on faces, have created an ending growth of conflicts through passion and reason within and outside the limits of their access, and set a criterion of moving power, to control the other limits on this universe.The basic object of writing this paper is to construct a framework or show a path leading to its construction for uniting mankind on one political platform, free from the influence of power and pressure. Keeping in mind the teaching of religious doctrine and their concept of world orders and the philosophical approaches, particularly the recent political writing of Kant towards inidvidual rights and freedom under the controlling factors of reason and passion, a framework for the new world order is possible to establish, leading to the final goal of creating a global system.  相似文献   

Discovery of antler from a new site in the Pinjor Formation (Pleistocene) of Pakistan     

Abdul Ghaffar  Muhammad Akhtar  Muhammad Akbar Khan  Abdul Majid Khan  Khizar Samiullah  Mehboob Iqbal 《Journal of the Geological Society of India》2012,80(1):119-122

Partially complete right antler from the Pinjor Formation (Pleistocene) of the Upper Siwalik Subgroup is identified, described and its phylogenetic relationship is discussed. The fossil antler is compared with other known fossil records of family Cervidae as well as with the extant species, on the basis of which it can be attributed to Axis punjabiensis. This species has not been reported previously from this fossil site.  相似文献   

Cervid remains from the middle Siwaliks of Hasnot (Late Miocene), Pakistan     

Muhammad Akbar Khan  Muhammad Akhtar  George Iliopoulos 《Journal of the Geological Society of India》2014,84(3):352-360

The late Miocene-early Pliocene fossil deposits of Hasnot in northern Pakistan have yielded a very rich vertebrate fauna. In this paper we describe the remains of Cervidae from six of these localities. By dental remains, at least four species of cervids are documented. These remains significantly widen the time distribution of the cervids and draw back the first appearance of cervids in the Dhok Pathan Formation of the Siwaliks. The data indicate a diverse set of coexisting ungulates in the area, subsisting within a mosaic of habitats.  相似文献   

Investigation of the properties of electrostatic IA solitary wave structures in negative ion magneto-plasmas with superthermal electrons     

S. Hussain  S. Ali Shan  N. Akhtar  M. M. Masud 《Astrophysics and Space Science》2014,352(2):605-612

A rigorous theoretical investigation is carried out in analyzing the excitation of electrostatic ion acoustic (IA) solitary wave (SW) structures in two dimensional negative ion magneto-plasmas with superthermal electrons (following κ type distribution). The Zakharov-Kuznetsov (ZK) equation is derived by employing the well known reductive perturbation method, and the analytical solution of ZK equation assists to find out the SW profiles along with their properties. The consequences of different plasma parameters (regarding our considered plasma system) variation on SW structures has been studied. It is found that magnetic field intensity, superthermal parameter κ and temperature of positive and negative ions as well as their densities significantly modify the basic characteristics (amplitude, width, etc.) of the SW waves. A comparison of the SW structures is also presented when the electrons are Maxwellian to when they are superthermal. The relevance of the findings of this work with astrophysical plasmas is briefly pointed out.  相似文献   

Effects of Replacing Fishmeal with Animal By-products Meal Supplementation in Diets on the Growth and Nutrient Utilization of Mangrove Red Snapper   总被引：1，自引：0，他引：1  

Khalid Jamil Ghulam Abbas Rukhsana Akhtar LIN Hong LI Zhenxing 《中国海洋大学学报(英文版)》2007,6(3):292-298

A feeding trial was conducted for 75 d to evaluate the nutritive value of a mixture of animal by-products(MAB) as a possible protein source in diets for juvenile mangrove red snapper,Lutjanus argentimaculatus(mean initial body weight,30 g). Fish were fed one of five isonitrogenous diets(40% crude protein) replacing 0,25%(MAB25),50%(MAB50),75%(MAB75) and 100%(MAB100) of fish meal protein with similar percentages of MAB. The MAB consisted of 25% cow liver meal,20% leather meal,20% meat and bone meal,15% blood meal,10% APC(poultry feather meal),8% poultry manure dried,1.5% choline and 0.5% chromic oxide. After 75 d of feeding,fish fed with diets MAB50,MAB75 and MAB100 exhibited significantly lower growth per-formance than that of fish fed with control and MAB25 diets. The optimum level of MAB was estimated to be 23%. Replacement of fish meal by MAB23% showed the following performance:maximum weight gain,510%;SGR,2.39% and FCE,2.83%. The MAB substitution up to 75% of fish meal protein in diets did not show differences in apparent protein digestibility(83.6% for MAB25,79.2% for MAB50,78.7% for MAB75) compared with control(83.4%),whereas in MAB100 group digestibility(65.3%) was sig-nificantly lower than in other groups. The apparent phosphorus absorption of test diet groups was significantly higher(37.1% for MAB25,28.5% for MAB50,55.6% for MAB75 and 54.5% for MAB100) than that of control(11.2%). The levels of protein and ash in the whole body,carcass and viscera increased as MAB substitution in diets increased,whereas lipids and moisture remained con-sistent among all treatment groups. These results showed that approximately 23% of fish meal protein could be replaced by a mixture of animal by-products for juvenile snapper growing from 30 g to 167 g in 75 d without compromising growth performance and feed efficiency.  相似文献   

Shocks in multicomponent cylindrical and spherical Lorentzian plasmas     

S. Hussain  N. Akhtar  S. Mahmood 《Astrophysics and Space Science》2013,343(1):329-333

Nonlinear cylindrical and spherical ion acoustic shocks have been studied in unmagnetized dissipative non-Maxwellian electron-positron-ion (e-p-i) plasmas. Modified Korteweg-de Vries Burgers (mKdVB) has been derived by using reductive perturbation method. Two level finite difference scheme is used with the help of Runge Kutta method to simulate the mKdVB. It is noticed that positron concentration, spectral indices of electrons and positrons, kinematic viscosity of ions significantly modifies the strength of shocks in cylindrical and spherical geometries.  相似文献