Vibration-based method for story-level damage detection of the reinforced concrete structure

Saqib Mehboob,Qaiser U. Zamana 사단법인 한국계산역학회 2021 Computers and Concrete, An International Journal Vol.27 No.1

This study aimed to develop a method for the determination of the damaged story in reinforced concrete (RC) structure with ambient vibrations, based on modified jerk energy methodology. The damage was taken as a localized reduction in the stiffness of the structural member. For loading, random white noise excitation was used, and dynamic responses from the finite element model (FEM) of 4 story RC shear frame were extracted at nodal points. The data thus obtained from the structure was used in the damage detection and localization algorithm. In the structure, two damage configurations have been introduced. In the first configuration, damage to the structure was artificially caused by a local reduction in the modulus of elasticity. In the second configuration, the damage was caused, using the Elcentro1940 and Kashmir2005 earthquakes in real-time history. The damage was successfully detected if the frequency drop was greater than 5% and the mode shape correlation remained less than 0.8. The results of the damage were also compared to the performance criteria developed in the Seismostruct software. It is demonstrated that the proposed algorithm has effectively detected the existence of the damage and can locate the damaged story for multiple damage scenarios in the RC structure.

Torrefaction and Hydrothermal Carbonization (HTC) of Dead Leaves

Saqib, Najam Ul,Park, Seong-Kyu,Lee, Jai-Young Korean Society of Soil and Groundwater Environment 2014 지하수토양환경 Vol.19 No.5

Torrefaction and hydrothermal carbonization (HTC) are productive methods to reclaim energy from lignocellulosic biomass. The hydrophobic, homogenized, energy dense and carbon rich solid fuel can be obtain from torrefaction and hydrothermal carbonization. Dead leaves were carbonized in a stainless steel reactor of volume 200 ml with torrefaction ($250-270^{\circ}C$) for 120 minutes and hydrothermal carbonization ($200-250^{\circ}C$) for 30 minutes, with mass yield solid fuel ranging from 57-70% and energy content from 16.81MJ/kg to 22.01 MJ/kg compare to the biomass. The char produced from torrefaction process possess high energy content than hydrothermal carbonization. The highest energy yield of 89.96% was obtained by torrefaction at $250^{\circ}C$. The energy densification ratio fluctuated in between 1.15 to 1.30. On the basis of pore size distribution of the chars, the definition of the International Union of Pure and Applied Chemistry (IUPAC) was used as a classification standard. The pore diameter was ranging within 11.09-19 nm which play important role in water holding capacity in soil. Larger pores can hold water and provide passage for small pores. Therefore, it can be concluded that high pore size char can be obtained my HTC process and high energy content char of 22.01 MJ/Kg with 34.04% increase in energy can be obtain by torrefaction process.

Dynamics and Vibrational Control of an Underwater Inverted Pendulum

Saqib Hasnain,Umer Hameed Shah,Sang-Hei Choi,Keum-Shik Hong 제어로봇시스템학회 2016 제어로봇시스템학회 국제학술대회 논문집 Vol.2016 No.10

This paper discusses the dynamics and vibrational control problem of an underwater inverted pendulum system. The system’s equations of motion are obtained by using the Lagrange equation. The vibrational control technique is applied to stabilize the inverted pendulum in water. Furthermore, stability analyses in terms of stable-unstable region for the underwater inverted pendulum system is presented. While a number of control techniques for the stabilization problem of an inverted pendulum in air by oscillating the support point have been developed, but a similar technique for the system in water has not yet been investigated. The dynamics of any system in liquid is strongly influenced by the density of the liquid and the relative velocity of the surrounding liquid. Also, it becomes a challenging task to stabilize the system in the presence of the hydrodynamic forces acting on it. Simulation results reveal that the application of the vibrational control technique newly developed in this paper can successfully stabilize the system in water under the influence of hydrodynamic forces.

Changes in postpartum metabolites and resumption of ovarian cyclicity in primiparous and multiparous dairy cows

Saqib, Muhammad Najmus,Qureshi, Muhammad Subhan,Khan, Rifat Ullah The Korean Society for Applied Biological Chemistr 2018 Applied Biological Chemistry (Appl Biol Chem) Vol.61 No.1

The postpartum period in high-yielding dairy cows creates an enormous drain of nutrients in favor of milk yield which antagonizes the resumption of ovulatory cycles. Therefore, a study was undertaken to evaluate the association of changes in postpartum serum metabolites with resumption of ovarian cyclicity. A total of 24 clinically healthy, freshly parturated primiparous (P-1) and multiparous (P-2) Holstein Frisian cows was selected. Cows were further divided on the basis of body condition score (BCS) 1 and 2 having BCS 3 or above 3, respectively. Weekly blood samples were collected and serum glucose, cholesterol, triglycerides, progesterone, and cortisol concentrations were determined for a period of 7 weeks. The glucose concentration was significantly (P < 0.05) higher in cows in P-2 during week 7. Cows in parity 2 had significantly (P < 0.05) high cholesterol during week 6 and 7. The serum triglyceride concentration in multiparous animals having BCS-2 during week 6 was increased significantly (P < 0.05). Serum cortisol was significantly (P < 0.05) high in P-1 during week 1 and 2 and significantly (P < 0.05) high in P-2 during week 7. Serum progesterone was significantly (P < 0.05) higher in cows during week 7 in P-2 having BCS-2. The increased serum progesterone concentration during postpartum period was associated with decreased levels of serum cortisol and more availability of cholesterol and glucose. The multiparous cows maintained the postpartum blood metabolite concentration and showed better adaptability to reproductive cyclicity during the postpartum period as compared to primiparous cows.

Forecasting Scheme for Swan Coastal River Streamflow Using Combined Model of IOHLN and Nin~o4

Saqib Ur Rehman,Kashif Saleem 한국기상학회 2014 Asia-Pacific Journal of Atmospheric Sciences Vol.50 No.2

The study aims to investigate the possible relationship between Niño 4 and Indian Ocean high longitude (IOHLN) with the Swan coastal river flow by constructing a regression model which predict streamflow patterns and which enables to obtain long time lead to forecasting, in a period when there was not much rainfall. Many streamflow forecast models use rainfall and runoff relationship, which is dependent on basin response time and hence cannot provide large forecasting lead time. For water resource management, this lead time of predictability is not capable for a long period of drying trend. Significant findings of this study suggest that Niño 4 and Indian Ocean high pressure longitude (IOHLN) can be used for forecasting of flow in Swan river. In this study not only qualitative forecast of Swan coastal river is presented based on the conditional probability, but also a quantitative forecast is done by combining Niño.4 and IOHLN indices using multiple regression, which shows enhancement over other climate indicators when used alone. The Conditional probability model correctly predict 7 years category of flow out of 8 years flow.

Modification of Oxygen-Ionic Transport Barrier of BaCo_0.4Zr_0.1Fe_0.4Y_0.1O₃Steam (Air) Electrode by Impregnating Samarium-Doped Ceria Nanoparticles for Proton-Conducting Reversible Solid Oxide Ce

Saqib, Muhammad,Lee, John-In,Shin, Ji-Seop,Park, Kwangho,Kim, You-Dong,Kim, Ki Buem,Kim, Jung Hyun,Lim, Hyung-Tae,Park, Jun-Young Electrochemical Society 2019 Journal of the Electrochemical Society Vol.166 No.12

<P>A reliable and high performance proton-conducting reversible solid oxide cell (P-RSOCs) is developed to generate electricity in a protonic ceramic fuel cell (PCFC) mode and to generate hydrogen gas in a protonic ceramic electrolysis (PCEC) mode in a single electrochemical device. Herein we propose a modified triple conducting (H<SUP>+</SUP>/O<SUP>2−</SUP>/e<SUP>−</SUP>) steam (air) electrode through the infiltration of an Sm<SUB>0.2</SUB>Ce<SUB>0.8</SUB>O<SUB>2-δ</SUB> (SDC) oxygen-ionic conductor, because the polarization resistance (<I>R<SUB>p</SUB></I>) of P-RSOCs mainly comes from the steam (air) electrode in both the operational modes. The SDC-infiltrated nanoparticles on the composite BaCo<SUB>0.4</SUB>Zr<SUB>0.1</SUB>Fe<SUB>0.4</SUB>Y<SUB>0.1</SUB>O<SUB>3+δ</SUB> (BCZFY)-BaCe<SUB>0.7</SUB>Zr<SUB>0.1</SUB>Y<SUB>0.2-x</SUB>Yb<SUB>x</SUB>O<SUB>3-δ</SUB> (BCZYYb) electrode result in a considerable improvement in the oxygen reduction reaction and oxygen evolution reaction catalytic activity at 600–700°C due to the extension of electrochemical active sites with the increasing of surface area. In addition, the enhanced ionic conduction of a triple conducting composite using infiltrated oxygen-ionic SDC conductors leads to an effective decrease in the <I>R<SUB>p</SUB></I> (1.388→1.079 Ω·cm<SUP>2</SUP> at 600°C symmetric cell) with improved cell performance in both the PCFC and PCEC modes. Furthermore, the NiO-BCZYYb anode-supported cell with the SDC-infiltrated composite BCZFY-BCZYYb air electrode shows excellent durability in the PCFC and PCEC modes without any degradation during 250 h each at 650°C.</P>

COEFFICIENT BOUNDS FOR GENERALIZED MULTIVALENT FUNCTIONS  

SAQIB HUSSAIN,NAZAR KHAN,SHAHID KHAN 장전수학회 2016 Proceedings of the Jangjeon mathematical society Vol.19 No.3

In this paper we introduce and study some new classes of analytic multivalent functions de…ned in the open unit disk E ={z : |z| < 1}. Certain applications of our main results by using extended fractional differential operator are given. The Fekete-–Szego like inequality is also obtained.

A Study of Feature Subset Selection Methods for Dimension Reduction

Saqib Hayat,Abdul Basit Siddiqui,Sajid Ali Khan 보안공학연구지원센터(IJSIP) 2014 International Journal of Signal Processing, Image Vol.7 No.1

Ultrasonic Targeting of NK Cell in Vessel Bifurcation for Immunotherapy: Simulation and Experimental Validation

Saqib Sharif,송형우,정대원,Hiep Xuan Cao,박종오,강병전,최은표 한국센서학회 2023 센서학회지 Vol.32 No.6

Natural killer (NK) cells play a crucial role in combating infections and tumors. However, their therapeutic application in solid tumorsis hindered by challenges, such as limited lifespan, tumor penetration, and delivery precision. Our research introduces a novel ultrasonicactuation technique to navigate NK cells more effectively in the vascular system, particularly at vessel bifurcations where targeted deliveryis most problematic. We use a hemispherical ultrasonic transducer array that generates phase-modulated traveling waves, focusingon an ultrasound beam to steer NK cells using blood-flow dynamics and a focused acoustic field. This method enables the preciseobstruction of non-target vessels and efficiently directs NK cells toward the tumor site. The simulation results offer insights into thebehavior of NK cells under various conditions of cell size, radiation pressure, and fluid velocity, which inform the optimization of theirtrajectories and increase targeting efficiency. The experimental results demonstrate the feasibility of this ultrasonic approach for enhancingNK cell targeting, suggesting a potential leap forward in solid tumor immunotherapy. This study represents a significant step in NKcell therapeutic strategies, offering a viable solution to the existing limitations and promising enhancement of the efficacy of cancer treatments.

URL Filtering by Using Machine Learning

Saqib, Malik Najmus International Journal of Computer ScienceNetwork S 2022 International journal of computer science and netw Vol.22 No.8

The growth of technology nowadays has made many things easy for humans. These things are from everyday small task to more complex tasks. Such growth also comes with the illegal activities that are perform by using technology. These illegal activities can simple as displaying annoying message to big frauds. The easiest way for the attacker to perform such activities is to convenience user to click on the malicious link. It has been a great concern since a decay to classify URLs as malicious or benign. The blacklist has been used initially for that purpose and is it being used nowadays. It is efficient but has a drawback to update blacklist automatically. So, this method is replace by classification of URLs based on machine learning algorithms. In this paper we have use four machine learning classification algorithms to classify URLs as malicious or benign. These algorithms are support vector machine, random forest, n-nearest neighbor, and decision tree. The dataset that is used in this research has 36694 instances. A comparison of precision accuracy and recall values are shown for dataset with and without preprocessing.