Design of Grooved Microstrip Patch Resonator Filters for Mobile Communication

Vivek Singh Kushwah,Geetam Singh Tomar,Sarita Singh Bhadauria 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.5

In advanced communication technology the microstrip filter has an important job in terms of selectivity and elimination of the undesired signals. In microwave and RF frequency applications the design of filter is complex task as lumped components cannot be used in this range of frequency. Microstrip filters are always preferred over the lumped filters at larger frequency for their compact size, lighter weight, lower cost and higher performance. In this paper the design of grooved microstrip patch resonator band-pass filter is presented at mid-band frequency 1.8 GHz for L-Band applications. It also acts as a band-reject filter at center frequency 1.1 GHz, which is innovative concept in microstrip filter design. Band-pass filter has a high attenuation in stop band, small insertion loss of 0.5744 dB and high return loss of 26.52 dB in the pass band whereas Band-reject filter has a low attenuation, high insertion loss of 21.95 dB and low return loss of 0.2432 dB in the stop band. The result is encouraging and fabrication is also very easy.

Molecular n-doping of chemical vapor deposition grown graphene

Singh, Arun Kumar,Iqbal, Muhammad Waqas,Singh, Vivek Kumar,Iqbal, Muhammad Zahir,Lee, Jae Hong,Chun, Seung-Hyun,Shin, Koo,Eom, Jonghwa The Royal Society of Chemistry 2012 Journal of materials chemistry Vol.22 No.30

<P>It is essential to tailor the electronic properties of graphene in order to apply graphene films for use in electrodes. Here we report the modification of the electronic properties of single layer chemical vapor deposition (CVD) grown graphene by molecular doping without degrading its transparency and electrical properties. Raman spectroscopy and transport measurements revealed that <I>p</I>-toluenesulfonic acid (PTSA) imposes n-doping on single layer CVD grown graphene. The shift of G and 2D peak wave numbers and the intensity ratio of D and G peaks are analyzed as a function of reaction time. In the gate voltage dependent resistivity measurement, it is found that the maximum resistivity corresponding to the Dirac point is shifted toward a more negative gate voltage with increasing reaction time, indicating an n-type doping effect. We have also made single layer graphene p–n junctions by chemical doping and investigated the current–voltage characteristics at the p–n junction.</P> <P>Graphic Abstract</P><P>It is essential to tailor the electronic properties of graphene in order to apply graphene films for use in electrodes. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2jm32716c'> </P>

Performance Comparison of Microstrip Band-Pass Filters for Different Dielectric Materials

Vivek Singh Kushwah,Geetam S. Tomar,김혜진 사단법인 인문사회과학기술융합학회 2016 예술인문사회융합멀티미디어논문지 Vol.6 No.10

In this paper design of Microstrip band-pass filters has been presented for different dielectric materials for GSM Guardband applications. The various designs have been investigated for performance and optimal solution has been provided in the work. The filter has been simulated using IE3D 14.1 simulation tool where various parameters have been obtained and performance has been measured using scattering parameters; Insertion loss and return loss of microstrip filter.

Performance Comparison of Microstrip High-Pass Filters for Different Dielectric Substrates

Vivek Singh Kushwah,G. S. Tomar,Sarita Singh Bhadauria,김혜진 사단법인 인문사회과학기술융합학회 2016 예술인문사회융합멀티미디어논문지 Vol.6 No.12

In this paper performance and design comparison of Microstrip high-pass filters are presented for different dielectric materials for L, S and C-band applications. IE3D 14.1 simulation tool is used for obtaining the Insertion loss and return loss performance of microstrip high pass filter.

Dual-mobility versus Fixed-bearing in Primary Total Hip Arthroplasty: Outcome Comparison

Vivek Singh,Jeremy Loloi,William Macaulay,Matthew S. Hepinstall,Ran Schwarzkopf,Vinay K. Aggarwal 대한고관절학회 2022 Hip and Pelvis Vol.34 No.2

Purpose: Use of dual mobility (DM) articulations can reduce the risk of instability in both primary and revision total hip arthroplasty (THA). Knowledge regarding the impact of this design on patient-reported outcome measures (PROMs) is limited. This study aims to compare clinical outcomes between DM and fixed bearing (FB) prostheses following primary THA. Materials and Methods: All patients who underwent primary THA between 2011-2021 were reviewed retrospectively. Patients were separated into three cohorts: FB vs monoblock-D vs modular-DM. An evaluation of PROMs including HOOS, JR, and FJS-12, as well as discharge-disposition, 90-day readmissions, and revisions rates was performed. Propensity-score matching was performed to limit significant demographic differences, while ANOVA and chi-squared test were used for comparison of outcomes. Results: Of the 15,184 patients identified, 14,652 patients (96.5%) had a FB, 185 patients (1.2%) had a monoblock-DM, and 347 patients (2.3%) had a modular-DM prosthesis. After propensity-score matching, a total of 447 patients were matched comparison. There was no statistical difference in the 90-day readmission (P=0.584), revision rate (P=0.265), and 90-day readmission (P=0.365) and revision rate due to dislocation (P=0.365) between the cohorts. Discharge disposition was also non-significant (P=0.124). There was no statistical difference in FJS-12 scores at 3-months (P=0.820), 1-year (P=0.982), and 2-years (P=0.608) between the groups. Conclusion: DM bearings yield PROMs similar to those of FB implants in patients undergoing primary THA. Although DM implants are utilized more often in patients at higher-risk for instability, we suggest that similar patient satisfaction may be attained while achieving similar dislocation rates.

Performance Comparison of Microstrip Band-Reject Filters for Different Dielectric Materials

Vivek Singh Kushwah,Geetam S. Tomar,Sarita Singh Bhadauria 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.10

In this paper design of Microstrip band-reject filters have been presented for different dielectric materials on L-band applications. The various designs have also been compared with different dielectric constants and other performance parameters to check for viability and stability of designs on the considered frequency band. IE3D 14.1 simulation tool has been used for obtaining the Insertion loss and return loss performance of microstrip filter.

Network Security in Embedded System Using TLS

Vivek Negi,Himanshu Verma,Ipsita Singh,Aditya Vikram,Kanika Malik,Archana Singh,Gaurav Verma 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.2

Security in terms of Networks have turn out to be more significant to Organizations, Military and personal computer user’s. Since various kinds of threats are for data from sending it from sender side over internet till it reaches to receiver. Here we will focus on SSL it is a technique used to give client and server authentication, data confidentiality and data integrity. It transform our data into unintelligible form, data which we will be sending can be text or no text form, by encrypting our data we can save it from attacks like eavesdropping, in which interception of communication by unauthorized person, he can either listen or can add malicious information in our data which can lead to catastrophic results. This technique of secure data transmission is very useful in securing the integrity of data sent by the Unmanned Aerial Vehicles in military application to commercially used Electricity meter. Since the above mentioned devices uses microcontroller to send data through internet hence this data is always going to be susceptible to above mentioned threats so it is important to ensure that it doesn’t fall in wrong hands, our objective is that our microcontroller sends the data to remote location has authenticity, confidentiality and integrity. First we will send some meaningful text already stored in controller of STM3240G Eval-board then that data will be sent to server. These encrypted packets will be sending to remote server through Ethernet. At the receiver end this data will be received and decrypted to get the original captured data.

Tailoring the Electrical Properties of Graphene Layers by Molecular Doping

Singh, Arun Kumar,Ahmad, Muneer,Singh, Vivek Kumar,Shin, Koo,Seo, Yongho,Eom, Jonghwa American Chemical Society 2013 ACS APPLIED MATERIALS & INTERFACES Vol.5 No.11

<P>It is an essential issue in graphene-based nanoelectronic and optoelectronic devices to tune the electrical properties of graphene layers, while preserving its unique band structure. Here, we report the tuning of electronic properties of single-, bi-, and trilayer mechanically exfoliated graphenes by <I>p</I>-toluenesulfonic acid (PTSA) molecular doping. Raman spectroscopy and charge transport measurements revealed that PTSA molecule imposes <I>n</I>-doping to single-, bi-, and trilayer graphenes. The shift of G and 2D peak frequencies and intensity ratio of single-, bi-, and trilayer graphenes are analyzed as a function of reaction time. The Dirac point is also analyzed as a function of reaction time indicates the <I>n</I>-type doping effect for all single-, bi-, and trilayer graphenes. Our study demonstrates that chemical modification is a simple approach to tailor the electrical properties of single-, bi-, and trilayer graphenes, while maintaining the important electrical assets.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2013/aamick.2013.5.issue-11/am401119j/production/images/medium/am-2013-01119j_0008.gif'></P>

Technique for single-stage reconstruction of obliterative or near-obliterative long urethral strictures in circumcised patients

Sher Singh Yadav,Vivek Kumar Singh,Vinay Tomar,Neeraj Agarwal,Anil Gulani 대한비뇨의학회 2018 Investigative and Clinical Urology Vol.59 No.3

Purpose: To report our initial experience with urethral reconstruction using a combined dorsal lingual mucosal graft (LMG) and ventral onlay preputial flap for long obliterative or near-obliterative strictures in circumcised patients. Materials and Methods: This was a retrospective study of 10 patients from January 2015 to June 2017 with long obliterative or near-obliterative anterior urethral strictures and circumcised prepuces. All patients underwent a combined approach using a dorsally LMG and a narrow preputial onlay flap ventrally to create a 26–30 Fr. neourethra over a 14-Fr Foley catheter. Success was defined as no requirement for additional urethral instrumentation. The follow-up period ranged from 6 to 32 months. Results: The patients ranged in age from 17 to 44 years (mean, 32.3±9.59 years) and stricture length ranged from 9 to 12.5 cm (mean, 10.77±1.15 cm). Four strictures were obliterative and six were near-obliterative. Two patients had a history of prior urethroplasty. The length of the LMGs harvested ranged from 11 to 14 cm (mean, 12.8±1.03 cm). The preputial flaps available were from 1 to 1.5 cm in width (1.29±0.16 cm) and the desired length. Maximum urinary flow rate (Qmax) achieved ranged from 12 to 26 mL/s (mean, 20.46±3.71 mL/s) after 3 months. One patient needed a single direct visualized internal urethrotomy and another patient develop temporary superficial penile necrosis. The success rate was 90%. Conclusions: Long obliterative and near-obliterative penile and penobulbar urethral strictures can still be treated in circumcised patients using available preputial skin along with lingual mucosa with good outcomes.

Living donor liver transplant outcomes during the COVID-19 pandemic: does a decrease in case volume impact the overall outcomes?

Shweta A. Singh,Hetal Pampaniya,Vikram Kumar,Mukesh Kumar,Shekhar Singh Jadaun,Vivek Yadav,Sanjiv Saigal,Subhash Gupta 대한이식학회 2022 Korean Journal of Transplantation Vol.36 No.2

Background: High-volume centers (HVCs) are classically associated with better out- comes. During the coronavirus disease 2019 (COVID-19) pandemic, there has been a decrease in the regular liver transplantation (LT) activity at our center. This study ana- lyzed the effect of the decline in LT on posttransplant patient outcomes at our HVC. Methods: We compared the surgical outcomes of patients who underwent LT during the COVID-19 pandemic lockdown (April 1, 2020 to September 30, 2020) with outcomes in the pre-pandemic calendar year (April 1, 2019 to March 31, 2020). Results: During the 6 months of pandemic lockdown, 60 patients underwent LT (43 adults and 17 children) while 228 patients underwent LT (178 adults and 50 children) during the pre-pandemic calendar year. Patients in the pandemic group had significant- ly higher model for end-stage liver disease (MELD) scores (24.39±9.55 vs. 21.14±9.17, P=0.034), Child-Turcotte-Pugh scores (11.46±2.32 vs. 10.25±2.24, P=0.03), and inci- dence of acute-on-chronic liver failure (30.2% vs. 10.2%, P=0.002). Despite performing LT in sicker patients with COVID-19-related challenges, the 30-day (14% vs. 18.5%, P=0.479), 3-month (16.3% vs. 20.2%, P=0.557), and 6-month mortality rates (23.3% vs. 28.7%, P=0.477) were lower, but not statistically significant when compared to the pre-pandemic cohort. Conclusions: During the COVID-19 pandemic lockdown the number of LT procedures performed at our HVC declined by half because prevailing conditions allowed LT in very sick patients only. Despite these changes, outcomes were not inferior during the pan- demic period compared to the pre-pandemic calendar year. Greater individualization of patient care contributed to non-inferior outcomes in these sick recipients.