Effectiveness of DOS (Dark-Object Subtraction) method and water index techniques to map wetlands in a rapidly urbanising megacity with Landsat 8 data

The objectives of this work were to examine the applicability of the Dark-Object Subtraction (DOS) atmospheric correction method and water-based index techniques to map wetlands in Dhaka megacity using Landsat 8 data. With the use of both raw data and DOS- corrected imagery, the analysis revealed that DOS- corrected images performed better in discriminating wetland areas. Furthermore, the Modified Normalised Water Index (MNDWI) was the most superior technique whilst the Normalised Difference Water Index (NDWI) was the least suitable in identifying the spatial locations of wetlands in a rapidly urbanising environment such as Dhaka

Understanding Flood Risk Management in Asia: Concepts and Challenges

In this chapter, an attempt is made to review the behavior of flood in Asian region and mechanism of flood risk management adopted among Asian nations. Flood is the most frequent natural disaster at present and vulnerability is widespread across the globe. Though, Asian region is on a knife-edge. Distribution of natural disasters in Asia followed by economic damage and human killing is illustrated in this chapter. In addition, discourse of China, Pakistan, India, Bangladesh, Indonesia, Nepal, Vietnam, and Sri Lanka on flood risk management is examined. Flood risk management policies framed by these nations over the period of time are synthesized. Research and investment on forecasting, planning, preparedness, assessment, evaluation, and mitigation of flood risk are explained. This synthesis can present a pathway for better response and flood management for debated Asian countries through filling the identified policy gaps. This chapter also urges a need of holistic and inter-countries research and cross country analysis followed by increased funding for sustainable management of risk

Efficiency and productivity in the takaful and insurance industries in Pakistan: a comparitive analysis

The comparisons of the efficiency insurance and takaful films which are operating simultaneously in the financial system need further investigation. The takaful industry is new player in the market which is struggling on its profitability specifically for developing country like Pakistan. This study investigates the existence of technical efficiency (TE), pure technical efficiency (PTE) and scale efficiency (SE) by applying Data Envelopment analysis (DEA) for the insurance and takaful sector from 2008 to 2016. This study measures the productivity change with Malmquist productivity index (MPI) for both insurance and takaful sector. In addition, this study also aims to identify the firm level attributes (asset size (SIZE), market share (MS), profitability (ROE) and leverage (LEV)) by Tobit Regression which determine the efficiency of insurance and takaful industry for Pakistan. The data for the fourteen insurance and four takaful firms is collected from the annual reports of the firms, State Bank of Pakistan reports and Insurance Association of Pakistan reports. The results highlight that takaful firms have more technical and pure technical efficiency as compared to the insurance firms whereas insurance firms attain more scale efficiency score for the study period. The takaful industry records the higher productivity than insurance firms measured by MPI. The results show the negative significant relation between SIZE and TE, SE of insurance and PTE of takaful and positive with TE and SE of takaful. MS is positive and significant with TE, PTE and SE of insurance and PTE of takaful. ROE is negative and significant with PTE of insurance and TE and SE of takaful. LEV is significant except to SE of insurance. The mixed results imply that policy makers and practitioners should develop different prudential regulations to improve scale efficiency especially for takaful industry by enhancing their branch network, new products development for adaptation of latest techniques and technology

Component-based mixed reality environment for the control and design of servo-pneumatic system

Synopsis Considerable research efforts have been spent over the last two decades on improving the design, control, and modelling of pneumatic servo drive systems including the development of dedicated controllers and control valves. However, the commercial updates in employing pneumatic servos are still largely limited to laboratory research usage and the initiatives in developing seem to have lost their momentums. Although this situation has some to do with the rapid development and availability of cost effective electric servo technologies, one reason is considered to be a lack of design and simulation tools for employing pneumatic servo drives. This research has therefore been conducted to address these concerns, and to demonstrate how appropriate tools and environments can be developed and used to aid in the design, control and commissioning of pneumatic servo drives. Because of the inherent high nonlinearities associated with pneumatic systems, it would be highly desirable if the simulation environment could be run in time domain so that it can be mixed with the real system. This would make the simulation more accurate and reliable especially when dealing with such nonlinear systems. Unfortunately, the tools that are available in the market such as Propneu (Festo, 2005) and Hypneu (Bardyne, 2006) are dedicated for pneumatic circuit design only. This research is aimed at developing a mixed reality environment for the control and design of servo-pneumatic systems. Working with a mixed reality environment would include both the capability to model the system entirely as a simulation, the so-called "off-line", as well as being able to use real components running against simulations of others "on-line", or in a Mixed Reality (MR) manner. Component-based paradigm has been adopted, and hence the entire pneumatic system is viewed as a series of component modules with standardised linking variables. The mathematical model of each individual component has been implemented in simulation software which produces time domain responses in order to allow for mixing the simulation with the real system. The main outcome of this research can be seen as a successful development and demonstration of the Component-based Mixed Reality Environment (CMRE), which would facilitate the control and design of servo-pneumatic systems. On the one hand, the CMRE facilitates the identification of some nonlinear parameters such as frictional \I ynopsis parameters. These parameters could cause great difficulties in servo-pneumatic modelling and control. Accurate friction parameters would give the ability to attain an accurate model, and therefore provide more flexibility in applying different control and tuning strategies on the real system. On the other hand, the CMRE facilitates the design process by enabling the designer to evaluate the servo-pneumatic system off-line prior to building the system. This would reduce the design time, increase the reliability of the design, and minimize the design cost. The concept of the CMRE was validated by tests carried out on laboratory-based prototype servo-drive. Close agreement between the experimental and simulated responses was obtained showing that the models have represented the real system adequately. Case studies were then conducted to demonstrate the validity of the proposed methodology and environment. In these case studies, PIDVF controller and cascade control structure were successfully implemented, synthesised, and tuned. The results revealed that the CMRE is an easy, accurate and robust way of implementing different control and tuning strategies on servo-pneumatic systems. Furthermore, the research has shown how the CMRE can lead to significant improvements in certain life cycle phases of the system, e.g. commissioning, maintenance, etc. This research has contributed to knowledge in the following: (1) Adopting the mixed reality concept and the component-based approach in order to create a CMRE in facilitating the control and design of servo-pneumatic systems. (2) A method to identify the friction parameters of a single-axis pneumatic machine, (3) Encapsulate existing control methods within the CMRE to be applied on the real system. (4) A scheme for controller tuning, in which the controller is tuned off-line and then applied on the real system, and hence avoided on-line tuning which can be troublesome and time consuming. It is anticipated that the concept of the CMRE can be extended to include multi-axes servo-pneumatic system, servo-hydraulic, and servo-electric drives. Therefore, conceptual model structures have been introduced in this research which can be considered as the foundation for creating similar environments for those systems

Evaluation of Static Horizontal Louvers on Annual Daylighting Performance in Classrooms

Daylighting has a great impact on students’ health, learning performance, and productivity. The goal of this paper is to enhance daylighting performance by examining year-round daylighting performance of Southern facades in the case of one central window in a classroom located in Cairo, Egypt by using static external horizontal shading devices during the Fall, Spring and Summer semesters The scope of the study is to evaluate and assess the effect of the window-to-wall ratio (WWR) in addition to the louvers’ configurations of depth and count parameters of the classroom on annual daylighting performance metrics for classrooms’ southern facades by using Rhinoceros, Grasshopper interface and Honeybee Plus plugin which uses the Radiance engine for annual daylighting Simulations. Annual Sunlight Exposure, Spatial Daylight Autonomy and upper and lower limits of useful daylight illuminance are incorporated for an efficient annual daylighting performance. Based on geographical location and sun altitude angles that is gathered from ladybug tools, three alternative configurations of fixed horizontal louvers were investigated to evaluate the difference between them. Results show a low difference with the proposed louver configurations cases and a high reduction in annual sunlight exposure by 78% which complies with LEED v4 and IES-LM-83-12 criteria

A Non-Reference Evaluation of Underwater Image Enhancement Methods Using a New Underwater Image Dataset

The rise of vision-based environmental, marine, and oceanic exploration research highlights the need for supporting underwater image enhancement techniques to help mitigate water effects on images such as blurriness, low color contrast, and poor quality. This paper presents an evaluation of common underwater image enhancement techniques using a new underwater image dataset. The collected dataset is comprised of 100 images of aquatic plants taken at a shallow depth of up to three meters from three different locations in the Great Lake Superior, USA, via a Remotely Operated Vehicle (ROV) equipped with a high-definition RGB camera. In particular, we use our dataset to benchmark nine state-of-the-art image enhancement models at three different depths using a set of common non-reference image quality evaluation metrics. Then we provide a comparative analysis of the performance of the selected models at different depths and highlight the most prevalent ones. The obtained results show that the selected image enhancement models are capable of producing considerably better-quality images with some models performing better than others at certain depths

Hypoglycemic status in low birth weight neonates during first 24 hours of life after birth

Objective: The study aimed to determine the frequency of hypoglycemia in low birth weight neonates during the first 24 hours of life after birth. Materials and Methods: This cross-sectional study was conducted from 1st March 2016 to 31st August 2016 in the NICU and postnatal ward of POF Hospital, Wah Cantt. All the babies with birth weight less than 2.5 kg including preterm and term were included in the study. After the aseptic measure blood, sugar was checked and a value less than 45 mg/dl was labelled as hypoglycemia. Results: Out of 96 neonates,51 (53%) were male and 45 (47%) were female.  The minimum weight of the patient was 1.6kg and the maximum was 2.40 kg. Hypoglycemia was noted in 49 (51%) babies after 2 hours of birth whereas 36 (37.5%) had hypoglycemia at 4 hours and 13 (13.5 %) had at 24 hours. 68 (70.8%) babies included in the study were appropriate for gestational age (AGA) and 28 (29.1%) babies were small for gestational age (SGA). After 2 hours of birth, hypoglycemia was present more in SGA babies i.e.20 (71.4%) as compared to AGA babies i.e. 29 (42.6%) which had statistical significance also (p-value 0.01). Conclusion: Neonatal hypoglycemia is a well-recognized complication in newborns and low birth weight infants are more susceptible to hypoglycemia. Early identification of vulnerable infants and the use of preemptive measures can result in better outcomes

Intussusception in an infant as a manifestation of COVID-19

Gastrointestinal manifestations of COVID-19 are rare and have primarily been limited to diarrhea or vomiting. Intussusception is the most common cause of bowel obstruction in infants, with up to 30% of pediatric intussusception cases having a preceding viral illness. We present the rare case of intussusception in a SARS-CoV-2 positive infant. This is the first documented case of survival in a SARS-CoV-2 positive patient presenting with intussusception as the primary manifestation. As our knowledge of this disease evolves, surgeons need to remain suspicious for possible gastrointestinal manifestations of COVID-19