3D-FDTD Method for Analysis of Rectangular Waveguide Loaded with Anisotropic Dielectric Material

One of the most popular techniques to solve electromagneticproblems numerically is using finite-difference timedomain(FDTD) method. The method has been successfullyapplied to an extremely wide variety of electromagnetic problems.The essential reason resides in the fact that the FDTD methoditself is extremely simple even for analyzing in a three-dimensional(3D) system. In this paper, the analysis of resonant frequencyfor a rectangular waveguide which is loaded with anisotropicdielectric material is numerically investigated based on 3D-FDTDmethod. The wave equations and modes that appear in thewaveguide are analyzed theoretically in which the results areapplied to validate the numerical result obtained from 3D-FDTDmethod. For comparison, an empty rectangular waveguide anda rectangular waveguide fully loaded with isotropic dielectricmaterial are also analyzed both theoretically and numerically.From the result, it shows that a good agreement has been achievedbetween theoretical calculation and 3D-FDTD numerical resultswith their discrepancies of 0.26–2.32%

3D-FDTD Method for Analysis of Rectangular Waveguide Loaded with Anisotropic Dielectric Material

One of the most popular techniques to solve electromagneticproblems numerically is using finite-difference timedomain(FDTD) method. The method has been successfullyapplied to an extremely wide variety of electromagnetic problems.The essential reason resides in the fact that the FDTD methoditself is extremely simple even for analyzing in a three-dimensional(3D) system. In this paper, the analysis of resonant frequencyfor a rectangular waveguide which is loaded with anisotropicdielectric material is numerically investigated based on 3D-FDTDmethod. The wave equations and modes that appear in thewaveguide are analyzed theoretically in which the results areapplied to validate the numerical result obtained from 3D-FDTDmethod. For comparison, an empty rectangular waveguide anda rectangular waveguide fully loaded with isotropic dielectricmaterial are also analyzed both theoretically and numerically.From the result, it shows that a good agreement has been achievedbetween theoretical calculation and 3D-FDTD numerical resultswith their discrepancies of 0.26–2.32%

HUBUNGAN CITRA TUBUH DENGAN KEPERCAYAAN DIRI SISWI SMAN 5 PEKANBARU

Penelitian ini bertujuan untuk mengetahui hubungan antara citra tubuh dengan kepercayaan diri siswi SMAN 5 Pekanbaru dimana banyak remaja yang tidak percaya diri dengan dirinya. Hipotesis dalam penelitian ini yaitu ada hubungan antara citra tubuh dengan kepercayaan diri. Data di ambil dengan cara stratified sampling karena ada tingkat yang membedakan. Data penelitian menggunakan teknik korelasi product moment, untuk try out jumlah subjek 219 dan penelitian berjumlah 240 masing- masing kelas harus terwakilkan. Data diperoleh dengan menggunakan skala kepercayaan diri dan skala citra tubuh. Hasil dari penelitian menunjukan bahwa ada hubungan antara citra tubuh dengan kepercayaan diri pada siswi SMAN 5 Pekanbaru dengan signifikan p = 0,004 (p<0,05) yang berarti memiliki hubungan antara variabel X dan Y. Besarnya sumbangsih citra tubuh dalam mempengaruhi percaya diri adalah 2,7%. Kata kunci : citra tubuh, kepercayaan dir

Hardware trojan enabled denial of service attack on CAN bus

The trend of technological advances in the vehicle industry illustrates that future cars would have added functionalities with smart features, better connectivity and autonomous behaviour. These naturally involve a higher number of Electronic Control Units (ECUs) being connected using existing conventional in-vehicle network protocols such as Controller Area Network (CAN). In this context, security of systems is now becoming a major concern while industry’s primary interest in the manufacturing of cars is reliability and safety. It is now in daily news that smart cars are being hacked due to weaknesses in their embedded electronics that provides ways of hardware attacks [1] [2]. Hardware Trojan (HT) is the threat that has been recently recognised as one of the primary sources of backdoor access that enables hackers to attack systems. As trouble, HT remains silent until a rare function/event triggers it for activation. This paper contributes to the challenge of demonstration of disruption in CAN buses raised from hidden Hardware Trojan. In this regard, it is presented how just a small size Hardware Trojan disrupts the CAN bus communication without an adversary having physical access to the bus. The attack is neither detectable via frame analysis, nor can be prevented via network segmentation; additionally, a rare triggering mechanism activates HT to process untraceable faults

Layered security for IEEE 1687 using a Bimodal Physically Unclonable Function

In this paper, a layered security mechanism for IEEE 1687 is proposed using a new class of physically unclonable function (PUF) called Bimodal PUF. It moves beyond the conventional single-challenge single-response PUF by introducing a second response to the PUF gained from the same single challenge. As an advantage, a double-response PUF forms two-layer security solution, one at the hardware layer by limiting the access to the embedded instrument and the second one for the data layer by securing the output data that needs to be transmitted. Experiments conducted with FPGA show that such advantages come in place at a small silicon area overhead, up to 1.4%, for a 64-bit security key. This is known to be sufficient enough to resist brute-force and machine learning attack

Delay-based true random number generator in sub-nanomillimeter IoT devices

True Random Number Generators (TRNGs) use physical phenomenon as their source of randomness. In electronics, one of the most popular structures to build a TRNG is constructed based on the circuits that form propagation delays, such as a ring oscillator, shift register, and routing paths. This type of TRNG has been well-researched within the current technology of electronics. However, in the future, where electronics will use sub-nano millimeter (nm) technology, the components become smaller and work on near-threshold voltage (NTV). This condition has an effect on the timing-critical circuit, as the distribution of the process variation becomes non-gaussian. Therefore, there is an urge to assess the behavior of the current delay-based TRNG system in sub-nm technology. In this paper, a model of TRNG implementation in sub-nm technology was created through the use of a specific Look-Up Table (LUT) in the Field-Programmable Gate Array (FPGA), known as SRL16E. The characterization of the TRNG was presented and it shows a promising result, in that the delay-based TRNG will work properly, with some constraints in sub-nm technolog

Delay-Based True Random Number Generator in Sub-Nanomillimeter IoT Devices

True Random Number Generators (TRNGs) use physical phenomenon as their source of randomness. In electronics, one of the most popular structures to build a TRNG is constructed based on the circuits that form propagation delays, such as a ring oscillator, shift register, and routing paths. This type of TRNG has been well-researched within the current technology of electronics. However, in the future, where electronics will use sub-nano millimeter (nm) technology, the components become smaller and work on near-threshold voltage (NTV). This condition has an effect on the timing-critical circuit, as the distribution of the process variation becomes non-gaussian. Therefore, there is an urge to assess the behavior of the current delay-based TRNG system in sub-nm technology. In this paper, a model of TRNG implementation in sub-nm technology was created through the use of a specific Look-Up Table (LUT) in the Field-Programmable Gate Array (FPGA), known as SRL16E. The characterization of the TRNG was presented and it shows a promising result, in that the delay-based TRNG will work properly, with some constraints in sub-nm technology

Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

© 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 licenseBackground: 80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality. Methods: This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494. Findings: Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70–8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39–8·80) and upper-middle-income countries (2·06, 1·11–3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26–11·59) and upper-middle-income countries (3·89, 2·08–7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications. Interpretation: Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications. Funding: National Institute for Health Research Global Health Research Unit