Risk Assessment of Dropped Cylindrical Objects in Offshore Operations

Dropped object are defined as any object that fall under its own weight from a previously static position or fell due to an applied force from equipment or a moving object. It is among the top ten causes of injuries and fatality in oil and gas industry. To solve this problem, several in-house tools and guidelines is developed over time to assess the risk of dropped objects on the sub-sea structures. This thesis focuses on compiling and comparing those methods in hope to improve the recommended practices available in the market. A simple modification is done on the in-house tools to better predict the landing point distribution of the dropped cylindrical objects on the seabed by imposing the random three-dimensional rotation around the water depth axis. This tool is then used to compare the result of annual hit frequency using the recommended practice and further compared with the available experimental data

The Diversity of Board of Directors Characteristics and Firm Value

The research contributes to provide insights on how characteristics of board of directors can affect firm value by analyzing board characteristics such as gender diversity, age and educational background to firm value of public firms in Indonesia. Generational diversity is being considered as an independent variable as it has never been assessed in Indonesia. Resource dependence theory and upper echelons theory are used in this research among other available concepts to explain the impact of board characteristics during the decision-making process and its access to resources. ROA is used in this research as the profitability approach indicator of firm value, while Tobin’s Q is used as the market approach indicator of firm value. Samples used in this research amounts to 1.151 samples from 411 companies. The results show that educational background and board age significantly affects firm value positively when measured by profitability approach indicator. While gender diversity and generational diversity both have no significant effect on firm value when measured by either profitability approach indicator or market approach indicator due to homogeneity. The results indicate that the appointment of directors with older age while possessing higher education can increase a company’s firm value which is measured by profitability indicators

Antioxidant Activity of Methanol Extract from Several Indonesian Green Teas

As a common beverage, green tea is supposed to have beneficial health effect, such as antioxidant. At present, there are many green teas available in the market in Jakarta. Their quality, in their antioxidant activity, should be proved. This study aimed to investigate the antioxidant activity of extracts of green tea products commercially available in Jakarta. Four green tea samples from different factories (coded as A, B, C, and D) were selected and macerated using methanol. DPPH radical scavenging activity, reducing power ability and total antioxidant capacity were used to measure the antioxidant activity. The total phenolic content (TPC) was also determined. The studied green teas had varied TPC from 23.80 to 84.03 mG GAE/g extract, ranked as B more than D more than A more than C. All samples exhibited various but strong antioxidant activity by DPPH assay, even better than standards ascorbic acid and butylated hydroxytoluene (BHT). However, all extracts showed similar activities in their reducing power ability and total antioxidant capacity, with activities less than standards. These findings confirm that the quality of the Indonesian commercial green teas were heterogeneous both in TPC or DPPH scavenging capacity. But, there is an indication that they are good as an antioxidant containing beverage

Numerical analysis of point absorber for wave energy conversion in Malaysian seas

Wave energy conversion by using point absorber has recently gained intensive research in renewable energy. However, a majority of research works only focused on the regions with high wave heights, which may not be readily achievable in Malaysian seas condition. As the technology of point absorber facing the concern on less-applicability in low wave height conditions in Malaysia, a numerical modeling to understand the maximum potential power output to be generated by point absorber is now in demand to predict the power capture ability of point absorber in Malaysian waters. In order to complete this research gap, this paper is aiming to determine the sensitivity of different configurations of power take-off system in point absorber and to numerically analyze the potential maximum power output to be generated by the point absorber in Malaysian water, under regular wave motion. The significance of this study leads to a better understanding of the envelope of power output generated by point absorber in Malaysian seas. The methodology is conducted with theoretical modeling of point absorber, developing a numerical model of power take-off system to identify the maximum magnetic flux density of different stator-translator configuration, and simulating the power output of point absorber in time-domain under regular wave condition based on Malaysia seas data. The results show that power output of point absorber can be increased by a double-sided stator. The envelope of maximum power output to be generated has been identified. This research provides a further understanding of the development of point absorber technologies in Malaysian seas condition

Incidence of HIV and hepatitis C virus among people who inject drugs, and associations with age and sex or gender: a global systematic review and meta-analysis

BACKGROUND: Measuring the incidence of HIV and hepatitis C virus (HCV) infection among people who inject drugs (PWID) is key to track progress towards elimination. We aimed to summarise global data on HIV and primary HCV incidence among PWID and associations with age and sex or gender.METHODS: In this systematic review and meta-analysis, we updated an existing database of HIV and HCV incidence studies among PWID by searching MEDLINE, Embase, and PsycINFO, capturing studies published between Jan 1, 2000, and Dec 12, 2022, with no language or study design restrictions. We contacted authors of identified studies for unpublished or updated data. We included studies that estimated incidence by longitudinally re-testing people at risk of infection or by using assays for recent infection. We pooled incidence and relative risk (RR; young [generally defined as ≤25 years] vs older PWID; women vs men) estimates using random-effects meta-analysis and assessed risk of bias with a modified Newcastle-Ottawa scale. This study is registered with PROSPERO, CRD42020220884.FINDINGS: Our updated search identified 9493 publications, of which 211 were eligible for full-text review. An additional 377 full-text records from our existing database and five records identified through cross-referencing were assessed. Including 28 unpublished records, 125 records met the inclusion criteria. We identified 64 estimates of HIV incidence (30 from high-income countries [HICs] and 34 from low-income or middle-income countries [LMICs]) and 66 estimates of HCV incidence (52 from HICs and 14 from LMICs). 41 (64%) of 64 HIV and 42 (64%) of 66 HCV estimates were from single cities rather than being multi-city or nationwide. Estimates were measured over 1987-2021 for HIV and 1992-2021 for HCV. Pooled HIV incidence was 1·7 per 100 person-years (95% CI 1·3-2·3; I 2=98·4%) and pooled HCV incidence was 12·1 per 100 person-years (10·0-14·6; I 2=97·2%). Young PWID had a greater risk of HIV (RR 1·5, 95% CI 1·2-1·8; I 2=66·9%) and HCV (1·5, 1·3-1·8; I 2=70·6%) acquisition than older PWID. Women had a greater risk of HIV (RR 1·4, 95% CI 1·1-1·6; I 2=55·3%) and HCV (1·2, 1·1-1·3; I 2=43·3%) acquisition than men. For both HIV and HCV, the median risk-of-bias score was 6 (IQR 6-7), indicating moderate risk. INTERPRETATION: Although sparse, available HIV and HCV incidence estimates offer insights into global levels of HIV and HCV transmission among PWID. Intensified efforts are needed to keep track of the HIV and HCV epidemics among PWID and to expand access to age-appropriate and gender-appropriate prevention services that serve young PWID and women who inject drugs.FUNDING: Canadian Institutes of Health Research, Fonds de recherche du Québec-Santé, Canadian Network on Hepatitis C, UK National Institute for Health and Care Research, and WHO.</p

The state of the Martian climate

60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Risk Assessment of Dropped Cylindrical Objects in Offshore Operations

Dropped object are defined as any object that fall under its own weight from a previously static position or fell due to an applied force from equipment or a moving object. It is among the top ten causes of injuries and fatality in oil and gas industry. To solve this problem, several in-house tools and guidelines is developed over time to assess the risk of dropped objects on the sub-sea structures. This thesis focuses on compiling and comparing those methods in hope to improve the recommended practices available in the market. A simple modification is done on the in-house tools to better predict the landing point distribution of the dropped cylindrical objects on the seabed by imposing the random three-dimensional rotation around the water depth axis. This tool is then used to compare the result of annual hit frequency using the recommended practice and further compared with the available experimental data

Prediction on parametric resonance of offshore crane cable for lowering subsea structures

Parametric resonance of offshore crane cable was predicted by using Mathieu equation to provide structural safety prediction during subsea lowering operation. This paper studied the predicting method of offshore crane cable to complement the safety management during subsea lowering operation. The offshore crane cable was modeled as a tensioned long cylindrical structure and Mathieu instability coefficients were utilized to predict the dynamic instability of the structure. Numerical analyses were conducted to predict the parametric resonance of cable and evaluate the sensitivity effective submerged length, dynamic tension variation. Dynamic instability at sub-harmonic 2:1 unstable region of Mathieu stability diagram potentially creates high risk for lowering operation if the damping coefficient is low. Dynamic tension variation can cause instability of offshore crane cable during passing through wave splash zone and landing subsea payload. The reduction of axial tension variation can stabilize the dynamic of offshore crane cable. Parametric resonance of cable is also sensitive to the total payload. The findings of this paper can enhance structural integrity prediction of offshore crane cable and complement to safety management during subsea lowering operation