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Utilities are looking for cost-effective solutions to improve the grid's power quality and stability. Applications of FACTS devices provide a popular and proven solution to reactive power compensation, mitigating grid instability, improving power quality and voltage stability. Amongst a plethora of FACTS devices, shunt controllers are the most sought-after power controllers in which the power electronics-based Static Synchronous Compensators or STATCOM is the popular state-of-the-art technology. The increasing penetration of distributed RE (DRE) based electricity generation plays a crucial role in supplying power to loads in remote areas, especially where the main grid system is inaccessible. Such areas are frequently suffering the problems of reliable power supply, power quality, and voltage instability. The Utilization of smart inverters based on dynamic reactive power compensation by Distributed-STATCOM (D-STATCOM) has enabled to qualitatively improve the end-user requirements in the electricity distribution system. The design and behavior of a simple filter assisted D-STATCOM for reactive power compensation during variation of inductive loads is the topic of this paper. A cost-effective ±200kVAr D-STATCOM armed with a novel output filter and improved PI controller employing the pulse width modulated (PWM) technique to IGBT based Voltage Source Converter is proposed to compensate reactive power requirement of loads and to improve transient and dynamic stability, limiting harmonic distortion within standard IEEE-519 limits. The proposed STATCOM design is simulated in Simulink/MATLAB, which confirms its satisfying dynamic reactive power compensation capabilities and low level of harmonic distortion.

To promote investment in the electricity sector, the deregulated electricity market regime has created an enabling environment to accelerate the all-around development of power generation, transmission and distribution systems. RE-based power generation is proliferating in the power sectors worldwide. Participation of large numbers of market players, and massive penetration of RE-generation have created enough complexities and has made fundamental changes in the deregulated electricity market conditions. Small scale RE generating units have limited participation in the electricity markets due to the uncertainties. These units integrate with other fossil fuel plants and forms as Virtual Power Plants (VPPs). Increasing participation of RE based VPPs in the competitive electricity market, has brought out further complexity in market operation primarily in terms of its generation scheduling, economic profitability, etc. In this paper a two-stage stochastic programming approach for optimal scheduling of VPPs in the electricity markets is presented, along with modeling of uncertainties in the electricity market price, available level of stochastic renewable generation and the request for reverse deployment. These uncertainties are modeled using scenario bounds and are formulated using stochastic programming approach. Simulation results are carried out on 4-h planning horizon.

The VSC-based multi terminal HVDC technology is gaining popularity in power system to integrate and efficiently operate multi-area AC systems of same or asynchronous frequency as one grid. Nevertheless, this technology has enabled to enhance controllability and stability of AC-DC integrated system. Depending upon the amount of power transfer between AC and DC systems, control strategy adopted for MTDC system varies. Master-Slave, Voltage Margin and Voltage Droop control are classical DC voltage control strategies for VSC-based MTDC systems. Although Voltage Droop technique is reliable but it suffers from drawbacks like inability to deliver constant active power to critical AC systems, inability to maintain DC voltage to a constant value, risk of irreversible switching from droop control mode to constant power control mode, etc. Voltage Margin technique is reliable than Master Slave control but suffers from power oscillations and large DC voltage overshoot when DC voltage control is transferred from main master controller to reserve controller. In this paper, an adaptive Master-Slave control technique with modulation of converter currents in Master terminal is proposed where direct-axis converter current is allowed to increase well up to maximum IGBT current carrying ability limit. Thus, augmented Master control scheme is able to compensate for more unbalanced power in DC grid than the conventional one thereby preventing severe DC overvoltage or arresting DC voltage from running down. The proposed control has enabled to improve the reliability and stability of AC-DC grid and is found to be more flexible than conventional Master-Slave control.

In order to meet existing and future load growth, capacity addition by economical RE generation and replacement of hydrocarbon-driven or fossil fuel-based alternators are the major trend in power system development worldwide. In effect, there is gradual decrease in system inertia. The intermittency and variability of RE-sources being a well-established phenomenon creates not only load-generation balancing issues in real time scale, but leads to system operational problems like wide frequency fluctuations, high rate of change of frequency, etc. This makes the power system very much prone to serious frequency insecurities. For secure operation of integrated EHVAC-HVDC hybrid power system, frequency regulation concept is embedded inside converter control systems and a telecommunication-independent active power frequency droop-based Converter Current Modulation technique using IGBT-based VSC HVDC system is proposed in this paper, which offers support to maintain stable frequency near nominal value in an interconnected power system during generation loss, load-switching or a fault in the system, avoiding any frequency dip. The proposed VSC-HVDC control scheme has been simulated by MATLAB/Simulink tool and performance of the controller is demonstrated to validate the superiority of the proposed scheme over the conventional vector current control scheme used in VSC-HVDC system.

With the vast expansion of grid network and enhancement of Communication system, Cyber security reinforcement is of paramount importance for reliable and secure power system operation. Cyber-attacks on electricity markets acquire financial profits to the adversary. In this paper a modest attempt is made to model the cyber attacker's objective of profit maximization by injecting false data into Day-ahead and Real Time electricity markets. It is considered that attacker runs a bi-level optimization problem which includes attacker's profit maximization objective and market clearing problem for finding out the optimal attack measurements. While manipulating the measuring devices like RTUs, the attacker takes care to avoid being detected by the bad data detection (BDD) procedure run by the ISO. This paper focuses on financially motivated FDI attacks considering attacker as one of the virtual players in electricity market. A novel attacking model is designed using bi-level optimization problem where attacker aims to gain financial benefits by misleading market clearing problem. Potential impact of financially motivated False Data Injection (FDI) attacks on electricity markets is presented by considering PJM 5-bus system. The simulation results show the sharp impact on Locational Marginal Prices (LMPs) in fulfilling the attacker's objective, and the distinct relationship between LMPs and the market clearing prices during the attack.

A hospital based cross sectional study was carried out to analyze diurnal variation of stroke and their association to sleep awake cycle. Four hundred and two patients of stroke admitted in different Medicine Units of Faridpur Medical College and Dhaka Medical College Hospitals from July 2012 to June 2013 were chosen using purposive sampling technique. Enrolled patients were with their first stroke, subsequently proved by CT scan of brain. The initial clinical diagnosis of stroke was made from history and examination obtained from the patient himself or from his/her attendant. The time of onset of stroke was recorded by attending doctor at the time of assessment and recorded on a fixed proforma. Patient who could not give history properly or had no responsible attendant and who had history of head injury, intracranial space occupying lesion or bleeding disorder were excluded from the study. Age ranged from 25 years to 98 years with mean age of 62.02 years (±SD 11.75 years). Out of 402 patients 59.7% suffered from ischemic stroke. Highest incidence of stroke (26.9%) occurred between 4:01am to 8:00 am and lowest (7.5%) between 8:01 pm to 12:00 am. Among the subtypes, ischaemic stroke has shown a single peak incidence at 4:01 to 8:00 am and lowest between 8:01 pm to 12:00 am. 50 % of ischaemic stroke cases developed between 0:01 am to 8:00 am. In this study, maximum number of patients developed hemorrhagic stroke between 4:01 am to 8:00 am (25.9%) and lowest number developed hemorrhagic stroke between 12:01 pm to 4:00 pm (9.3%). This study confirms the diurnal variation of both hemorrhagic and ischaemic stroke in Bangladesh and most of them occurs in early morning after wakening.Faridpur Med. Coll. J. 2014;9(2): 80-83

Stroke is one of the most common medical emergency. A total number of 100 randomly selected clinically and CT proven acute stroke patients were studied at medicine and neurology ward of Faridpur Medical College Hospital (FMCH), Faridpur from January to July, 2014 with a view to study the clinical features and risk factors of Stroke. Among 100 patients, stroke was found most commonly in 59-70 years age group. Ischaemic stroke was 56%, haemorrhagic stroke was 39% and haemorrhagic infarct was 5%. Most of the patients were male with male-female ratio was 1.6:1. The commonest risk factor was hypertension found in 60%, diabetes mellitus found in 17%, smoking was present in 54% patients and dyslipidaemia was present in 22% cases. History of heart disease (Myocardial infarction was present in 2% patients, valvular heart disease was present in 4% patients) was present in 6% patients. The commonest presentation in both ischaemic and haemorrhagic stroke was hemiplegia (61%). Headache (14%) and vomiting (10%) were found to be more common accompaniment in haemorrhagic stroke. Loss of consciousness was present in 34% patients. Alcohol intake was not found in any patient.Faridpur Med. Coll. J. Jan 2016;11(1): 23-25

CorrigendumThe Article "Families with neurocutaneous syndromea - Report of two Cases" was published in JDMC Vol.22(1) in April 2013. The name of one of the authors was written 'Prodip Kumar Sarker', which is to be read as 'Prodip Kumar Sarkar'. (4th August 2014)Neurocutaneus syndrome is inherited as autosomal dominant condition.Tuberous sclerosis is one of the important neurocutaneous disorder characterized by development of widespread hamartomatous lesions involving skin, brain, kidney, retina etc. Recently we came across two cases of tuberous sclerosis. Both cases presented with status epilepticus and had a positive family history but the first case also had family history of neurofibromatosis. DOI: http://dx.doi.org/10.3329/jdmc.v22i1.15709 J Dhaka Medical College, Vol. 22, No. 1, April, 2013, Page 102-107

Road traffic accidents in Bangladesh have been rapidly increasing with huge mortality through road accidents each year. There are many causes of road accidents in recent years; one important cause is running of locally made improvised three wheelers (flat bed tricycle) in the urban areas and also on the highways, popularly known as 'Nasimon' and 'Karimon'. This prospective study was carried out in Faridpur Medical College Hospital from January through June 2011, to study the accident patients caused by 'Nasimon' and 'Karimon'. Fifty six (12%) patients were of RTA by 'Nasimon' and 'Karimon' out of a total of 468 patients admitted into our hospital during this period. Most patients (41, 73.21%) were male, highest accidents (24, 42.86%) were observed among 21-30 years age group and most victims (33, 58.93%) were belonged to low socioeconomic status. Commonest (31, 55.36%) victims were passengers of 'Nasimon' and 'Karimon' while maximum number of accidents (46, 82.14%) took place in the urban areas and on the highways. Injury pattern of victims were similar to that found in any other road accident patients. These three wheelers 'Nasimon' and 'Karimon' are run in violating of Bangladesh Motor Vehicles Act (1983) as they are totally unfit for plying on the highways. Strict surveillance against these illegal and risky vehicles on the highways and in the urban areas by law enforcing agencies is required as a measure to reduce the burden of road accidents in our country.DOI: http://dx.doi.org/10.3329/fmcj.v7i1.10289Faridpur Med. Coll. J. 2012;7(1): 06-09

Upper GI bleeding is a common medical emergency with a significant mortality, outcome of which depends upon the cause, appropriate and early intervention in a specialized center. This study was carried out to see the outcome of patient with Upper GI haemorrhage. Fifty cases with episode of upper gastrointestinal haemorrhage, admitted into medicine units of Faridpur Medical College Hospital from January 2011 to December 2011, were studied. Duodenal ulcer was the commonest cause of haematemesis and melaena followed by oesophageal varices, gastric ulcer and erosive gastritis. The peak incidence was among 35 to 45 years of age. Over all male female ratio was 4.55:1 but in case of duodenal ulcer it was 9:1. During hospital stay recurrent bleeding was noted in 10% of patients and during subsequent follow up it was 10% of the total and 50% in case of variceal bleeding group. Over all hospital mortality was 4% . DOI: http://dx.doi.org/10.3329/fmcj.v8i1.16891 Faridpur Med. Coll. J. 2013;8(1): 15-17

Miller Fisher Syndrome (MFS) is characterized by acute onset of ophthalmoplegia, ataxia and loss of tendon reflexes with relative sparing of strength in the extremities and trunk. Our patient Mr. Akter Sheikh, 40 years male, non diabetic, non hypertensive, presented with generalized weakness and difficulty in walking for 7 days preceded by a history of respiratory tract infection. After clinical and CSF examination, he was diagnosed as a case of Miller-Fisher syndrome. With treatment he improved significantly.Faridpur Med. Coll. J. Jan 2015;10(1): 44-45

Bronchial Asthma (BA) is a chronic airway disorder with significant morbidity and mortality but due to recent advances in the field of medicine most patients with BA can have complete symptom control and live a normal life. There are various routs of drug delivery for asthma control but among them aerosol inhalation is considered the optimal route. A number of pressured Metered Dose Inhalers (MDI) & Dry Powder Inhalers (DPI) are available for this purpose. However inhalation of therapeutic aerosols is not without difficulty, it requires precise instructions on the inhaler maneuvers, which is different from spontaneous normal breathing. Also, the characteristics of the inhaler device have to be suitable for the user. Available data indicate that, lack of knowledge demonstrated by health professionals & patients on the inhalation maneuvers & handling of inhalers resulting in a reduction of therapeutic benefit. The paper reviews the literature concerning the fundamental aspects of inhaler devices, inhalation maneuvers & device selection, in an attempt to increase the knowledge of and to optimize the clinical use of therapeutic inhalers. As a result of which Asthmatics can be kept under good control. Key words: Bronchial Asthma; MDI; DPI; Inhalation technique; Rotahaler; Cozyhaler. DOI: http://dx.doi.org/10.3329/fmcj.v6i2.9212 FMCJ 2011; 6(2): 104-106