History Matching Using Principal Component Analysis

Imperial Users onl

Geopolitical Risk and BRICS Volatilities

The effects of the Russia-Ukraine crisis on the stock market volatilities of BRICS countries (Brazil, Russia, India, China, and South Africa) are examined in this paper. The research draws on data from the closing prices of countries’ leading stock market indexes from February 1, 2020, up to July 26, 2024. The well-known GARCH (1,1) model supports the study to capture volatility persistence within a geopolitical context defined by its increasing uncertainty driven by the war between Russia and Ukraine. The core research findings show increased volatility in the Russian MOEX index at the early stages of the war, suggesting high levels of short-term volatility arising from geopolitical events in which Russia is directly involved. The shocks for the Russian market are short-lived, with similar results revealed for the rest of the countries that showed relatively stable behaviour, indicating a fast reaction to the geopolitical shock emerging from the Russian and Ukrainian war. The findings offer insights into the countries’ ability to withstand geopolitical changes, which could be explained by the potential diversification and growing vitality of the BRICS block. Among the BRICS countries, the Brazilian index IBOVESPA was identified as the most stable market, suggesting that aftermarket shocks make it relatively easy to return to its stability levels. The results offer interesting insights into the impact of geopolitical risks and the vulnerability exhibited by some emerging economies, providing evidence on how the BRICS countries differ in their reaction to the Russian-Ukrainian war and underlining the necessity of economic diversification and the importance of analysing countries’ geopolitical orientation to minimise the adverse impact of geopolitical risk on stock market fluctuations within a changing geofinance context

A Honeypot for Research on VoIP Systems Security

Byla vyvinuta technologie VoIP (Voice over Internet Protocol) a její význam v širokopásmové síti rychle roste. Telefony VoIP volají po stejné trase používané pro síťový a internetový provoz a čelí stejné kybernetické hrozbě, jakou dnes trápí datovou síť. Tyto hrozby zahrnovaly útoky odmítnutí služby, viry, narušení dat. Ve srovnání s technologickým boomem a tím, jak výroba zařízení pro IP telefonii přináší technologii do masové oblasti, se bezpečnostní problém nebo obavy sítě IP telefonie zbledly. V minulosti jsme již viděli, jak mnoho rozvinutých technologií čelí skutečné výzvě až poté, co se tyto technologie stanou boomem na trhu a široce přijaty společnostmi. Tento dokument vysvětluje bezpečnostní riziko, problémy spojené se sítí VoIP a různé typy útoků, kterým VoIP čelí; také popisuje kroky, které pomáhají zabezpečit síť VoIP organizace.Voice over Internet Protocol (VoIP) technology has been developed, and its importance in the broadband network is rapidly increasing. VoIP phones call on the same route used for network and internet traffic and face the same cyber threat that plagues the data network today. These threats included denial-of-service attacks, viruses, data breaching. The security issue or concern of the Ip telephony network pales compared to the technology boom and how IP telephony equipment manufacture brings technology to the mass area. In the past, we already have seen the many developed technologies face the real challenge only after these technologies become a boom in the market and widely adopted by the companies. This paper explains the security risk, problems associated with the VoIP network, and different types of attacks faced by the VoIP; it also outlines the steps for helping to secure an organization's VoIP network

Weak and Semi Compatible Maps in Probabilistic Metric Space Using Implicit Relation

2000 Mathematics Subject Classification: 54H25, 47H10.The concept of semi compatibility is given in probabilistic metric space and it has been applied to prove the existence of unique common fixed point of four self-maps with weak compatibility satisfying an implicit relation. At the end we provide examples in support of the result.Authors thank to MPCOST, Bhopal for financial support through the project M-19/2006

Anteromedial versus trans-tibial technique for anterior cruciate ligament reconstruction using quadrupled hamstring graft: a comparative study

Background: Femoral tunnel position plays a pivotal role for successful outcome in anterior cruciate ligament (ACL) reconstruction surgeries. Recently, the anteromedial techniques have gained popularity over the trans-tibial technique due to better anatomical position and better stability rotationally and antero-posteriorly then the later. The aim of the present study was to compare the technical difficulty and ease, functional and radiological outcome of trans-tibial and anteromedial portal techniques in ACL reconstruction.Methods: Thirty patients between March 2015 and February 2016 with ACL tear underwent arthroscopic reconstruction using quadrupled hamstring graft and were divided into two groups A (anteromedial) and group B (trans-tibial) as per the technique used. Patients with multiligament injuries, revision surgeries, and osteoarthritis knee were excluded. All the patients were followed-up for 24 months and clinical Lysholm and IKDC scores along with radiological outcome were calculated.Results: The mean age of patients were 32.4±6.3 years. Isolated ACL tear was seen in 16 (53.4%) cases followed by medial meniscus injury in 11 (36.6%) patients. The mean duration between injury and surgery was 14.8±8.99 and 21.6±3.23 days in group A and B respectively (p=0.0122). The radiological position of femoral tunnel in sagittal and coronal plane was statistically significant in both the groups. The Lysholm and IKDC scores showed statistically significant difference at 3 months post-operatively.Conclusions: Anteromedial and trans-tibial techniques have similar long term functional outcomes. However, more anatomical position of the graft through the anteromedial technique and better rotational and anteroposterior stability makes it theoretically to be superior to the trans-tibial technique

Comparison of efficacy of azilsartan with olmesartan in patients of hypertension: randomized controlled trial

Background: Azilsartan and olmesartan are members of ARBs, used in the management of hypertension. Objective was to evaluate efficacy of azilsartan with olmesartan in patients of hypertension. Methods: A randomized, prospective, open label, comparative study was carried out in Pharmacology and Medicine department at Dr. RPGMC Kangra at Tanda, HP. The study stretched over one year and blood pressure was monitored at first, third and sixth month. Out of 69 patients, 35 patients in group A were prescribed tablet azilsartan 40 mg/day and 34 patients in group B patients were prescribed tablet olmesartan 20 mg/day. Tablet chlorthalidone 12.5 mg/day was add on in both the groups. Data was presented as mean+SD. Student’s t test was used and p value <0.05 was considered significant. Results: In group A, systolic blood pressure (SBP) values improved from baseline of 153±10 mmHg to 111±18 mmHg (p<0.001) at 3 months and 109±6.1 mmHg (p<0.001) at 6 months and diastolic blood pressure (DBP) values from baseline of 87±7 mmHg to 67.1±4.6 mmHg (p<0.001) at 3 months and 67.6±2.5 mmHg (p < 0.001) at 6 months. In group B, SBP values improved from baseline of 154±8.5 mmHg to 127±3.6 mmHg (p<0.001) at 3 months and 123±4 mmHg (p<0.001) at 6 months and DBP values from baseline of 85±6.5mm Hg to 75.7±3.3 mmHg (p<0.001) at 3 months and 73±3.3 mmHg (p<0.001) at 6 months. On intergroup comparison improvement in hypertension was better in azilsartan group (p<0.001). Conclusions: The study concluded that azilsartan is significantly better than olmesartan in controlling the hypertension