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Fire in a seven-storied ready-made garments (RMG) factory building, based on the actual drawing of an existing RMG building, is simulated and the tenability of the occupants isanalyzed. The modeling is conducted by using PyroSim,a computational fluid dynamics (CFD) tool with the capability of simulating fire and optimized for low-speed, thermally-driven flow. A number of factors including temperature, visibility, and CO concentration are analyzed to examine their effects on the tenability of different zones and floors. The source of the fire is considered to be the fabric storage of the ground floor andnylon, a commonly used fiber in the RMG industries with a high heat release rate, is selected as the fuel. It is found that within 3 min of the initiation of the fire, fire-smoke spreads very rapidly through the hallways and stairways and completely blocks the escape routes of the building. From the point of view of an efficient evacuation process, the conditions in the 1st floor are found to be the most critical as fire and dense smoke surround the escape routes with a high degree of visibility reduction within 2 min. The available safety egress time is found to be small unless the smoke migration ismitigated by the use of fire doors and other smoke management techniques. Findings of this study will be helpful in the assessment of fire risk in the RMG buildings in Bangladesh and would enable to suggest design measures to control the propagation of fire and smoke and improve tenability, thus minimizing the life and property damages.

A hybrid dc-dc step-down converter is designed to achieve a low output to input voltage conversion ratio with high efficiency. Both switched capacitor and switched inductor topologies are used to develop the proposed buck converter. The mathematical model of the proposed buck circuit is derived considering continuous conduction mode of operation. The steady-state analysis of the converter is validated by simulation result from MATLAB SIMULINK The proposed converter maintains efficiency higher than 90% for a load of 100W–250W.

Designing hydrophobic surfaces with controllable wettability has attracted much interest in the recent times. The present study seeks to simulate the static and dynamic wetting behavior of liquid droplets on horizontal flat and microgrooved surfaces and compare the findings with experimentally obtained data. Using an open-source software, a 3D drop-shape model is developed to numerically analyze the shape of liquid droplets and anisotropic wetting for a wide range of parametric space. The effects of droplet volume, variation in the microgroove geometry and wettability gradient along the parallel and perpendicular directions of the microgrooved surfaces etc . on the drop shape and apparent contact angle are examined. Simulation and analysis are extended to analyze the wetting behavior of V-grooved geometry and are compared with the findings on rectangular microgrooved surfaces. For creating wettability gradient along the parallel direction of the grooves, periodic PDMS (Polydimethylsiloxane) coating is considered and increased hydrophobicity of the surface is observed with significant increase in the parallel contact angle for this case. The simulated results manifest considerable differences in the wetting pattern of the microgrooved and flat surfaces and are found out to be in good agreement with the experimental findings.

Energy harvesting technology has the ability to create self-powered electronic systems that do not rely on battery power for their operation. Wind energy can be converted into electricity via a piezoelectric transducer during the air flow over a cylinder. The vortex-induced vibration over the cylinder causes the piezoelectric beam to vibrate. Thus useful electric energy at the range 0.2-0.3V is found which can be useful for self-powering small electronic devices. In the present study, prototypes of micro-energy harvester with a shape of 65 mm × 37 mm × 0.4 mm are developed and tested for airflow over D-shaped bluff body for diameters of 15, 20 and 28mm in an experimental setup consisting of a long wind tunnel of 57cm × 57cm with variable speeds of the motor for different flow velocities and the experimental setup is connected at the downstream where flow velocity is the maximum. Experimental results show that the velocity and induced voltage follows a regular linear pattern. A maximum electrical potential...

Reduced core weight and material cost, higher corrosion resistance are some of the major eye catching properties to study polymers over metal in heat exchanger applications in spite of the former’s relatively low thermal conductivity and low strength. In the present study, performance of polymer parallel thin tube heat exchanger is numerically evaluated for cross flow liquid to air applications for a wide range of design and operating parameters such as tube diameter, thickness, fluid velocity and temperature, etc. using Computational Fluid Dynamics (CFD). Among a range of available polymeric materials, those with a moderate to high thermal conductivity and strength are selected for this study. A 90 cm × 1 cm single unit of polymer tubes, with appropriate number of tubes such that at least a gap of 5 mm is maintained in between the tubes, is used as a basic unit and multiple combination in the transverse direction of this single unit is simulated to measure the effect. The tube inner diameter is varied fr...

The present study aimed to evaluate the feasibility of coconut coir pads, jute fiber pads and sackcloth pads as alternative pad materials. Experimental measurements were conducted and the experimental data were quantitative. The experimental work mainly focused on the effects of different types and thicknesses of evaporative cooling pads by using forced draft fan while changing the environmental conditions. Experiments are conducted in a specifically constructed test chamber having dimensions of 12’X8’X8’, using a number of cooling pads (36”X26”) with a variable thickness parameters of the evaporative cooling pads i.e., 50, 75 and 100 mm. Moreover, the experimental work involved the measurement of environmental parameters such as temperature, relative humidity, air velocity, water mass flow rate and pressure drops at different times during the day. Experiments were conducted at three different water mass flow rates (0.25 kgs−1, 0.40 kgs−1 & 0.55 kgs−1) and three different air velocities (3.6 ms−1, 4.6 ms−1& 5.6 ms−1). There was a significant difference between evaporative cooling pad types and cooling efficiency. The coconut coir pads yielded maximum cooling efficiency of 85%, whereas other pads yielded the following maximum cooling efficiency: jute fiber pads 78% and sackcloth 69% for higher air velocity and minimum mass flow rate. It is found that the maximum reduction in temperature between cooling pad inlet and outlet is 4°C with a considerable increase in humidity. With the increase of pad thickness there was an increment of cooling efficiency. The results obtained for environmental factors, indicated that there was a significant difference between environmental factors and cooling efficiency. In terms of the effect of air velocity on saturation efficiency and pressure drop, higher air velocity decreases saturation efficiency and increases pressure drop across the wetted pad for maximum flow rate. Convective heat transfer co-efficient has an almost linear relationship with air Velocity. Water consumption or evaporation rate increases with the increase in air velocity. Finally, the present study indicated that the coconut coir pads perform better than the other evaporative cooling pads and have higher potential as wetted-pad material. The outcomes of this study can provide an effective and low-cost solution in the form of evaporative cooling system, especially in an agricultural country like Bangladesh.

Casualty of garment factory workers from factory fire in Bangladesh is a recurring tragedy. Smoke, which is more fatal than fire itself, often propagates through different pathways from lower to upper floors during building fire. Among the toxic gases produced from a building fire, carbon monoxide (CO) can be deadly, even in small amounts. This paper models the propagation and transportation of fire induced smoke (CO) that resulted from the burning of synthetic polyester fibers using two open source platforms, CONTAM and Fire Dynamics Simulator (FDS). Smoke migration in a generic multistoried garment factory building in Bangladesh is modeled using CONTAM where each floor is compartmentalized by different zones. The elevator and stairway shafts are modeled by phantom zones to simulate contaminant (CO) transport from one floor to upper floors. FDS analysis involves burning of two different stacks of polyester jacket of six feet height and with a maximum heat release rate per unit area of 1500kw/m2 over a storage area 50m2 and 150m2, respectively. The resulting CO generation and removal rates from FDS are used in CONTAM to predict fire-borne CO propagation in different zones of the garment building. Findings of the study exhibit that the contaminant flow rate is a strong function of the position of building geometry, location of initiation of fire, amount of burnt material, presence of AHU and contaminant generation and removal rate of CO from the source location etc. The transport of fire-smoke in the building Hallways, stairways and lifts are also investigated in detail to examine the safe egress of the occupants in case of fire.

At the end of a defrost, part of the frost melt water is retained on the surface, which freezes in the following frosting cycle. An experimental study is conducted on microgrooved and flat brass surfaces to examine the effects of the variation of the microgroove geometry and frost melt water retention on the cyclical frost growth and on frost properties. It is found that the dimensional variation of the microgroove texture affects these frost properties even in the refrost cycles. Density of the frost layer is increased by about 5–20% in the refrost cycles than in the 1st frost cycle for all the surfaces. The variation of frost properties becomes repeatable and periodic from the 3rd frost cycle. Incorporating microgrooves on a flat surface results in an increase in the frost thickness and a decrease in the frost density in all frosting cycles (by about 5–25%). The possible relationship of the obtained water drainage enhancement from the microgrooved surfaces with the variation of frost properties due to the change in groove dimensions is examined. Findings of this study can provide a more comprehensive idea of the possible effects of incorporating microgrooves on heat transfer surfaces operating under frosting/defrosting conditions.

The present cross-sectional study was conducted in the Department of Pathology, Dhaka Medical College Hospital, Dhaka over a period 12 months to evaluate the usefulness of intra-operative imprint cytology in diagnosing various breast lesions and to compare its diagnostic accuracy with those of frozen and paraffin sections. A total of 101 cases of breast tumours, diagnosed clinically or mamographically, who underwent elective surgery were consecutively included in the study. The mean age of the patients was 37.7 – 14.5 years. The sensitivity and specificity of imprint cytology in differentiating breast carcinoma from those who did not have breast carcinoma were 91% and 94.1% respectively. The positive and negative predictive values (PPVs and NPVs) of the test were 96.8% and 84.2% respectively. The percentages of false positive and false negative were 3.2% and 15.8% respectively. The overall diagnostic accuracy of imprint cytology was 92%. The sensitivity of frozen sections in correctly diagnosing carcinoma of breast was 95.5%, while the specificity of the test in ruling out those who did not have carcinoma was 97.1%. The positive and negative predictive values of the test were 98.5% and 91.7% respectively. The percentages of false positive and false negative were 1.5% and 8.3% respectively. The overall diagnostic accuracy of the test was 96%. The overall diagnostic accuracy of the two procedures is almost comparable. However, the imprint cytology has merit over frozen section in that it can be done quickly and thus helps operating surgeons to decide about margin clearance. JCMCTA 2013 ; 24 (2): 4-8

Through a systematic study of microgrooved brass surfaces, the effect of parallel, periodic microgroove geometry on the wettability is examined experimentally and compared to that of flat surfaces, where the drop size is comparable to the groove dimensions.A total of 18 brass samples are fabricated by micromachining without any chemical modification of the surface The substrates have groove depths in the range of 26 to 122 μm, groove widths of 27 to 187 μm, and are about 45 mm x 45 mm in size, with a thickness about 3 mm.A high degree of wetting anisotropy is observed on most of the microgrooved surfaces. A significantly higher value of static contact angle (SCA) in the orthogonal direction (across the grooves) of the grooves is observed on the microgrooved surfaces compared to the contact angle on the flat baseline surfaces which are hydrophilic in nature.The contact angle also shows a significant dependence on droplet volume. The observed wetting behavior is attributed to the manner in which droplets rest on these surfaces, contact line pinning by the groove edges and texture and local variation of roughness of the micromachined brass surfaces.

Osteoporosis is one of the most notable causes of bone fracture and approximately 200 million women are affected by osteoporosis worldwide. According to a report of International Osteoporosis Foundation, at least one in five men and one in three women in Bangladesh suffer a bone fracture due to osteoporosis in their remaining lifetime. Limited data is available in the open literature on osteoporosis among women in Bangladesh and more so on the micro-structural analysis of osteoporosis. The present study particularly aims at identifying the trend of osteoporosis of women of in Bangladesh, with special emphasis on the mechanical micro-structural analysis of female bones. A comprehensive statistical analysis has been conducted by collecting data of 250 Bangladeshi females with age ranging from 20 to 80 years. Trabecular bones of Tibia of female have been analysed with computed tomography for micro-structural assessment. To characterize several parameters of trabecular bones, the computed tomography scans have been analysed and parameters like bone volume fraction, fractal dimension etc. have been evaluated. A correlation between structural properties of the bones has been formed by multiple regression analysis. It shows a positive correlation between fractal dimension and bone volume fraction of the specimens.

In this study, frost is grown on microgrooved and flat brass samples under specific operating conditions and a comparison of the condensation, frosting, and defrosting pattern on microgrooved and flat brass surfaces is carried out experimentally. The surfaces are fabricated by a mechanical micromachining process and no chemical alteration of the surface is conducted. It is found that the shape, size, and distribution of condensed water droplets and the subsequent frost structure are significantly affected by the presence of microgrooves on the surface. The condensed water droplets take an elongated shape and then coalesce along the pillars and grooves on the microgrooved surfaces, giving a parallel “brick-wall-like” frosting pattern. The frost crystals on these microgrooved surfaces exhibit more directional growth parallel to the surface, with numerous ice flakes growing in the perpendicular and angular directions to the grooves. This nonuniform growth of the frost layer also gives the appearance of a spo...

The retention of water on the air-side surface of heat exchangers is important in air conditioning, refrigeration, and heat pumping applications. Recently, surfaces with grooves tens to hundreds of micrometers deep and wide have been proven highly effective in promoting water drainage from heat exchangers. Dynamic wetting behavior governs the motion of drops on such surfaces, and this work provides the first data on the dynamic wetting behavior on microgrooved metallic surfaces. Moving drops on microgrooved surfaces can be in a Wenzel or Cassie–Baxter wetting state. In a Wenzel wetting state, drops are elongated and have a tail; the length of the tail increases with Wenzel roughness. In a Cassie–Baxter wetting state, drops become more elongated as the Cassie–Baxter roughness increases. Drops in the Wenzel and Cassie–Baxter wetting states have dynamic advancing contact angles that increase with drop velocity and dynamic receding contact angles that decrease with velocity. In the Cassie–Baxter state, dynami...

The variation of frost structure and properties with groove geometry on microgrooved brass surfaces (45 mm × 45 mm) is examined through an experimental study. Frost is grown on a number of microgrooved brass samples having a wide range of groove dimensions (groove depth ≈ 27–122 μm, pillar width ≈ 26–187 μm and fixed groove width of 130 μm), and on one flat baseline surface under a range of substrate temperature and relative humidity conditions. Frost structure on the microgrooved surfaces, especially at the early stages of frost formation, is found to be significantly affected by a variation of the groove geometry. Depending on the rate of cooling of the substrate and variation of the groove geometry, the condensed droplets, which predominantly form on top of the pillar surfaces, either merge with the droplets on the grooves and fill the grooves completely, or bridge with droplets on the adjacent pillars and grooves, or freeze on the top of the pillars. These differences in the initial frost formation pattern are also found to considerably affect the thickness and density of the frost layer in frosting cycles up to 4 h long. Microgrooved samples with the deepest groove (122 μm) and widest pillar (187 μm) within the sample space, which exhibit similar frost structure at the early stages of frost formation, are found to have lower frost thickness and higher frost density among all the microgrooved samples. The relationship between the frost structure and frost properties with groove dimensions is discussed, emphasizing the importance of the morphological features.

Network coding has become increasingly popular in time efficient data dissemination due to its inherent nature of broadcasting multiple data items in encoded form through a single broadcast. However, not much attention has been put forth on the efficiency of network coding when accessed data items' sizes can vary. In this work, we have investigated that when clients' accessed data items are of different sizes, network coding based broadcast can no longer maintain its superiority over traditional broadcast. We have found the reason of this performance degradation of coding based broadcast and propose an efficient dynamic threshold based coding approach. The proposed approach can maintain its performance superiority over both traditional broadcast approach and conventional coding based approach under a range of different size accessed data items. Simulation results support our claim.

From the dawn of advanced aerospace technology, the aspect of stability and automated control is an important field of research interest providing ease of handling and friendly assistance for piloting. Considering this challenging aspect, development of automated control system is chosen for this research. The aim of this paper is to design a longitudinal autopilot for a general aviation aircraft and to analysis the performance of the developed model both for normal condition and atmospheric disturbance. To improve the overall performance, stability of the system and to overcome the atmospheric disturbance a compensator along with a PID controller has been designed. Simulation results of MATLAB Simulink have been also analyzed.

This work is aimed at developing a way to harvest energy from a fluid stream with the application of piezoelectric transducers in a small channel. In this COMSOL Multiphysics based simulation study, it is attempted to harvest energy from the abundant renewable source of energy available in the form of kinetic energy of naturally occurring flow of fluids. The strategy involves harnessing energy from a fluid-actuator through generation of couples, eddies and vortices, resulting from the stagnation and separation of flow around a semi-circular bluff-body attached to a cantilever beam containing a piezoceramic layer. Fluctuation of fluidic pressure impulse on the beam due to vortex shedding and varying lift forces causes the flexible cantilever beam to oscillate in the direction normal to the fluid flow in a periodic manner. The periodic application and release of a mechanical strain upon the beam effected a generation of electric potential within the piezoelectric layer, thus enabling extraction of electrica...

A Multiple Model Adaptive Estimation (MMAE) based approach of fault diagnosis for Li-Ion battery is illustrated in this paper. Electrochemical modelling approach is integrated with MMAE for fault diagnosis. This real physics based model of Li-ion battery (with Li-Co-O2 cathode chemistry) with nominal model parameters is considered as the healthy battery model. Battery fault conditions such as aging, overcharge and over discharge causes significant variations of parameters from nominal values and can be considered as separate models. Output error injection based Partial Differential Algebraic Equation (PDAE) observers are used to generate the residual voltage signals. These residuals are then used in MMAE algorithm to detect the ongoing fault conditions of the battery. Simulation results show that the fault conditions can be detected and identified accurately which indicates the effectiveness of the proposed battery fault detection method.

Understanding the relationship between surface roughness and wetting state is essential in designing microstructured surfaces with tunable wetting properties. In this work, an analytical model for predicting the wetting state on microgroove geometry is developed and applied to intrinsically hydrophilic brass surfaces with a wide range of groove geometry. To enhance the scope and applicability of the developed model, it is implemented on a number of other aluminum microgrooved surfaces. Before applying any surface minimization algorithm to obtain equilibrium droplet shape, the stable wetting state is determined by comparing the total surface energy of the liquid droplet in Cassie and Wenzel wetting state. It is found that hybridization of the microgrooved surface (PDMS coating on the groove base) reduces the critical microgroove dimensions for exhibiting a Cassie wetting state. The unusual spreading of water droplets, observed experimentally on certain microgrooved surfaces, is predicted more accurately when slightly inclined pillars (with a 7° inclination from vertical) instead of vertical wall are assumed. These results corroborate our earlier claim that the shape and the slope of the pillar edge are responsible for the unusual spreading exhibited by certain surfaces. Moreover, implementation of the experimentally obtained values of droplet elongation ratio in the numerical model further enhances the accuracy of the obtained results. The present mathematical model offers an excellent tool for predicting the wetting state of the rough hydrophilic surface using its roughness geometry, and the numerical approach of implementing inclined pillar and droplet elongation ratio can improve the accuracy of drop shape simulation while predicting the wetting states accurately.

Frost formation on heat exchangers is an undesirable phenomenon often encountered in different applications where the cold surface with a temperature below freezing point of water is exposed to humid air. The formation of frost on the heat transfer surface results in an increase in pressure drop and reduction in heat transfer, resulting in a reduction of the system efficiency. Many factors, including the temperature and moisture content of air, cold plate temperature, surface wettability etc., are known to affect frost formation and growth. In our present study, a model for frost growth on rectangular, periodic microgroove surfaces for a range of microgroove dimension (ten to hundreds of micron) is presented. The mathematical model is developed analytically by solving the governing heat and mass transfer equations with appropriate boundary conditions using the EES (Engineering Equation Solver) software. For temperature, a convective boundary condition at frost-air interface and a fixed cold plate surface temperature is used. Instead of considering the saturation or super-saturation models, density gradient at the surface is obtained by considering experimentally-found specified heat flux. The effect of surface wettability is incorporated by considering the distribution of condensed water droplets at the early stage of frost formation. Thickness, density and thermal conductivity of frost layer on the micro-grooved surfaces are found to vary with the dimension of the grooves. The variation of density and thickness of the frost layer on these micro-grooved surfaces under natural convection is numerally determined for a range of plate temperature and air temperature conditions and is compared with experimental results found in the open literature.

Drainage of frost melt water from a number of microgrooved brass surfaces, fabricated by micro-end-milling process, is investigated experimentally and compared to that of a flat baseline surface. Frost is grown on sample surfaces (45 mm × 45 mm in dimension) inside a thermally controlled chamber, at a plate temperature of about −25 °C in the presence of cold air (−6 °C) and retention of water on these surfaces after defrosting is studied for three different defrosting energy inputs. Microgrooved surfaces drain up to 70% more condensate than does the flat baseline. The groove geometry is found to considerably affect the water retention. Drainage is promoted by an increase in the pillar width but is relatively insensitive to the changes in the groove depth. Effects of defrosting heating rate on the frost surface temperature and substrate temperature during defrosting process is also investigated. Frost mass per unit area is found to be lower for the grooved surfaces in the 1st frost and 2nd frost cycles.

In this paper, performance analysis and the effectiveness of Orthogonal Frequency Division Multiplexing (OFDM) for different channels environment has been analyzed and investigated. In order to accomplish these tasks, an OFDM system model has been considered where a random bit sequence is generated and subsequently converted into decimal value depending on the word size of the system. In order to simulate the system, the power delay profile of different wireless channels, numbers of carriers, window type, and symbol duration have been chosen as simulation parameters. The whole system has been analyzed by modeling a transmission-reception OFDM wireless system using MATLAB code for four different channels i.e. urban, rural, terrain and rician channel. Factors that affect the performance of an OFDM system such as multipath delay spread, channel noise, distortion of the signal (clipping), and timing requirements have also been measured. Our study reveals that, for each channel the system must satisfied the conditions of flat fading. It has been realized that for total symbol duration of 80 microseconds to 148 microseconds, the whole system gives a satisfactory result for terrain channel. In these range of symbol duration, the performance seems to be at least 120 microseconds of length.

The resilience concept requires greater attention to human livelihoods if it is to address the limits to adaptation strategies and the development needs of the planet's poorest and most vulnerable people. Although the concept of resilience is increasingly informing research and policy, its transfer from ecological theory to social systems leads to weak engagement with normative, social and political dimensions of climate change adaptation. A livelihood perspective helps to strengthen resilience thinking by placing greater emphasis on human needs and their agency, empowerment and human rights, and considering adaptive livelihood systems in the context of wider transformational changes.

Skin diseases are among the most common health problems worldwide. In this article we proposed a method that uses computer vision based techniques to detect various kinds of dermatological skin diseases. We have used different types of image processing algorithms for feature extraction and feed forward artificial neural network for training and testing purpose. The system works on two phases- first pre-process the colour skin images to extract significant features and later identifies the diseases. The system successfully detects 9 different types of dermatological skin diseases with an accuracy rate of 90%.

House fire is one of the major concerns for designers, builders, and residents of property. In the case of detecting fire, individual sensors have been used for a long time, but they cannot detect the level of fire and notify the emergency response units. To solve this problem, this study attempts to propose an intelligent early fire detection system that would not only detect the fire by using integrated sensors but also notify the appropriate authorities including fire department, ambulance services, and local police station simultaneously to protect valuable lives and properties. Signals from the integrated detectors e.g., heat, smoke, and flame go through the machine learning algorithms to check the potentiality of the fire as well as broadcast the predicted result to various parties using a GSM modem. To consolidate the predicted output, structured forest for fast edge detection has also been applied. The final outcome of this development also minimized false alarms, thus making this system more reliable.

As the prices of conventional fossil fuels are monotonically increasing and the environmental impacts are becoming more serious concerns among people, the focus on the renewable energy has been increasing around the world. Among all the solar technologies, photovoltaic (PV) is the most promising one which converts solar energy into electrical energy. In recent years, Building Integrated Photovoltaic (BIPV) systems have become more popular due to the increased attention that renewable energy resources have received as well as the decreasing trend of the manufacturing costs of PV panel and related accessories. This paper evaluates the cost effectiveness of BIPV system for a building in Dhaka considering the local as well as international market prices of different components of BIPV system. The overall cost of the system is compared with the local electricity tariff. The per unit electricity cost of the BIPV system is also compared with that producing from different fossil fuels. The result shows an encouraging feature for BIPV system in Bangladesh.

Because of the increased demand and unsteady nature of solar power, solar energy storage methods are urgently needed, especially for mini-grid system where PV panels are the only source of energy. This paper intends to find out the more competitive solar energy storage system between two alternatives. They are, solar power system integrated with the pumped storage scheme and solar power system assisted by lead acid battery storage option. Though pumped storage scheme is unprecedented in smaller systems and its potential in a tiny scope is not proven, we incorporated it in a small system & tested its compatibility against the conventional lead acid battery storage system. It is observed that the pumped storage scheme is almost half as efficient yet more expensive than the conventional battery storage option.

For sustainable competitive advantages companies need innovation. However, for very few organizations innovation is a part of their DNA and for the most of companies it is a crisis element of “Constructive Destruction.” However, the recent economic crisis and evolution of business organization demand for innovative leaders who can do the miracle (innovation) in the organization. Like any new phenomenon, innovative leadership idea is blurry among different people and also experts are divided in their opinion. This paper tries to solve these puzzles by integrating the thought in a clear understandable picture. To solve the puzzle this paper first stated about creativity, innovations and leadership to better understand about innovative leadership process. Then it discussed in detail about the innovative leadership process followed by two examples of best practice and worst practice.Innovative leadership is the combination of four elements: emotional intelligence, management innovations, innovative organization and interaction with stakeholders. These are interrelated part that enforce each other to foster innovations. Emotional intelligence make the leader effective in performance because he can build trust and make people committed towards the goal; it becomes easy for him to do management innovations, develop innovative culture and interact with the stakeholders. Management innovations set the goal, principles and policy to guide the innovations and innovative culture foster to do the miracle by the employees. When inside is ready for the innovations the innovative leader interacts with the stakeholders for ideas and feedback. However, the innovative leader needs to apply sense when to be innovative and when not to be.

The aim of this study is to portray the status of awareness among Bangladeshi people. Six major characteristics- Rule of Law, Transparency, Responsiveness and Participation, Consensus oriented, Equity and inclusiveness, Accountability, Effectiveness and efficiency have been threaded to quantify different aspects of the complex concept of Corporate Governance. Study identified significant variance in different segment of the society. Inconsistency is also due in relation to different characteristics of the concept. As a new born nation unawareness is in tolerance level but this status is not satisfactory.

This research examines the attitudes of university students of Dhaka city towards advertising. The data were collected from randomly selected 200 students from both private and public universities in Dhaka city. The respondents were solicited to answer a self-administered questionnaire consisting of 20 statements about advertising. R-mode factor analysis, frequency distribution were used to explore data. The consequences of the study reveal that students have positive judgment about the economic impact of advertising. However, they have negative judgment about the ethical and social consequences of advertising. The students stipulate more regulations to control the advertising. The study recommends that advertisers should design factor-oriented, entertainment, excitement based advertising which may contain some sorts of emotional messages keeping in mind the traditions of Bangladesh. The advertising agencies should create successful advertising messages to reach the customers. Moreover, the study makes available a useful benchmark for future research studies.

Introduction: Self-care activities are crucial for managing diabetes nephropathy (DN), and there is not enough data on this in Bangladesh. The main target of this study was to identify the qualitative differences of self-care activities between patients attending government health facilities and private health facilities. Materials and Methods: This is a cross-sectional study conducted among the patients of DN attending government health facilities and private health facilities in Bangladesh using self-made survey question, and SPSS software version 16 was used for analysis. Results: A total of 200 ( n = 200) patients were taken, 100 from government health institutes and 100 from private health institutes. In both sectors, most of the patients were between 51 and 70 years old. In government sectors, the percentage of following healthy eating plans all days of a week was 47%, at least 30 min of physical activities on a regular basis was 39%, blood sugar testing at least once in a month was 79%, washing feet on all days of a week was 63%, having fruits/vegetables all days of a week was 27%, glomerular filtration rate (GFR) checked within the last month was 17%, having high-fat diet all days of a week was 22%, and having fried food all days of a week was 38%. In private sectors, the percentage of following healthy eating plans all days of a week was 76%, at least 30 min of physical activities on a regular basis was 58%, blood sugar testing at least once in a month was 88%, washing feet on all days of a week was 91%, having fruits/vegetables all days of a week was 63%, GFR was checked within the last month was 42%, having high fat diet all days of a week was 35%, and having fried food all days of a week was 42%. Conclusion: The patients of DN attending private health facilities were comparatively more aware and serious about self-care than the patients attending government health facilities in Bangladesh, and government health facilities should provide awareness program on this aspect.

In the present study, we report the contact angle hysteresis and drainage behavior of water drops on a number of brass surfaces with parallel microgrooves and compare them to the flat baseline surfaces. Parallel micro-grooves with different groove dimensions are fabricated by micro end-milling process without any modification of the surface chemistry. Advancing and receding contact angles in both parallel and perpendicular direction of the grooves and also the drainage behavior of water droplets on the microgrooved surfaces is found to be considerably affected by change in groove geometry parameters. Very high hysteresis is observed for both low (< 0.2) and high aspect ratio (> 0.7) of grooves and also for surfaces with lower groove spacing due to the droplets being in a Wenzel state. For intermediate aspect ratio (0.25–0.70) and larger spacing of the grooves, droplets remain in a Cassie state and the hysteresis is lower in both directions than that on the flat surfaces. Variation of critical sliding angle (angle at the point of incipient sliding of water droplets due to gravity) with groove geometry is investigated for a range of water droplet volume of 15 to 75 μl. Droplets of all volumes are found to slide much more readily on grooved surfaces than when placed on the flat baseline surfaces. Height and spacing of the grooves are also found to have significant influence on the sliding of the water droplets, as critical inclination angle decreased with groove height and increased with groove spacing. The results from this study may be useful in a broad range of applications where water retention plays an important role.

Minimization of condensate (frost melt water) retention on a surface operating under frosting/defrosting condition is of tremendous importance in a wide range of air conditioning and refrigeration applications. In the present study, the wetting characteristics, condensation and frosting pattern and the drainage of frost melt water from aluminum surfaces with parallel microgrooves have been examined and compared to the flat baseline surfaces. These surfaces are fabricated by topographical modification only, via standard photolithographic process. The microgrooved samples exhibit wetting anisotropy and static contact angles are as high as 149 and 112° when viewed from parallel and perpendicular directions to the grooves, respectively. Frost is grown on the samples inside a thermally controlled chamber at 3 different plate temperatures of −8°C, −13°C and −18°C, air temperature of 20±2°C and for 3 relative humidity conditions (50%, 70% and 90%). The duration of the frosting cycle is 45 minutes and tests are continued up to 5 frosting cycles, each time defrosting for a certain length of time at the end of frosting period. Significantly different size, shape and distribution of condensed and frozen water droplets on the grooved surfaces are observed from that on the flat baselines. The microgrooved samples are found to manifest better water drainage behavior and drained up to 50% more melt water compared to the flat baseline surfaces. While the amount of water retention on the baseline surfaces increases in the subsequent refrost cycles and is highest in the 5th frost cycle, the microgrooved surfaces show consistently improved water drainage in all cycles.

Thermoloop is a pulsated two-phase thermosyphon (PTPT) comprising of evaporator, condenser and a liquid reservoir with associated tubing and fittings with a view to cooling electronic devices. This study presents an experimental investigation on the thermoloop to address some issues on design and heat transfer performance. The evaporator employed in this study was of 72.5 mm × 60 mm × 20 mm in dimension with inside volume of 75 cm3. The reservoir had a liquid storing capacity of 80 cm3. A copper tubular condenser was used as the heat sink having two different convection conditions. For various heat input, evaporator wall temperatures, condenser inlet and outlet temperatures and reservoir liquid column height were recorded at a regular interval. For the variation of heat input from 100 W to 250 W, the maximum temperature of the evaporator wall increased from 106°C to 112°C and the minimum temperature of evaporator wall increased from 73°C to 95°C at an evaporator fill ratio of 30%. The values of other functional parameter such as cycle time, height of liquid column in the reservoir and condenser temperature also increased with an increase in thermal load. The inclusion of a fan to cool the condenser increased the operational limit of the device from 125 W to 275 W. This thermoloop device transported heat in cyclic and pulsated manner; the amount of heat transported was as high as 250 W with a thermal resistance of 0.116 m2K/W. Furthermore, various functional parameters of the thermoloop attained a steady value after 5 to 6 heat transport cycles.

Most basic DHT based peer-to-peer networks distribute objects among nodes in a way that tends to balance loads among the peers if the distribution of objects in the identifier space is uniform. But this doesnpsilat hold in practice. The case is further complicated by the fact that, in a typical scenario, object loads and node capacities vary enormously. Additionally, a nodepsilas load may vary greatly over time since the system can be expected to experience continuous insertions and deletions of objects, and continuous arrival and departure of nodes. This paper presents a scheme that can balance load in any DHT based P2P network even in a dynamic environment.

Character order in unicode for Bengali is different from the sorting order suggested by the governing authority. As a result, simple letter by letter comparison does not yield correct order of Bengali words. The presence of modifier characters in Bengali made the situation more complicated. The objective of our study is to adapt the suggested collation order for unicode represented Bengali text while achieving maximum possible efficiency. Here we propose an algorithm for this purpose. The proposed algorithm is applicable to any chosen sorting order. Also it compares words in O(1) time, irrespective of their lengths. Thus complexity of sorting texts is always O(n log n).

Stained glasses form an important element in human history. Since stained glasses are multifunctional, they have been utilized both in religious and civil architecture. Various conservation techniques such as mechanical, chemical, and the latest one being laser-based cleaning have been utilized. This work aims at making contributions to the knowledge about laser-glass interaction. The three main laser-glass interactions are photo-thermal, photo-chemical, and photo-mechanical. Experiments were carried out in burst and in continuous mode using a 800 ps n-IR laser with a wavelength of 1064nm. A pulsed/burst mode produces a sequence of a defined number of pulses with a high repetition rate. Contemporary glasses and historical pieces were used. The results realized will be important in the establishment of a laser tool selection criterion for decontamination/conservation of actual in-situ historic stained glasses and also develop a dynamic, automated, or semi-automated laser conservation method for historic glass. Complementary analytical techniques used include scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), confocal microscopy among others. The generally expected outcomes are to develop a practical criterion to apply lasers in cultural heritage; develop skills necessary to select, operate safely and apply lasers to problems in cultural heritage materials in general.

Stained glasses form an important element in human history. Since stained glasses are multifunctional, they have been utilized both in religious and civil architecture. Various conservation techniques such as mechanical, chemical, and latest one being laser-based cleaning have been utilized. This work aims at making contributions to the knowledge about laser-glass interaction. The three main laser-glass interactions are photo-thermal, photo-chemical, and photo-mechanical. Experiments were carried out in burst and in continuous mode using an 800 ps n-IR laser with a wavelength of 1064nm. A pulsed/burst mode produces a sequence of a defined number of pulses with a high repetition rate. Contemporary glasses and historical pieces were used. The results realized will be important in the establishment of a laser tool selection criterion for decontamination/conservation of actual in-situ historic stained glasses and also develop a dynamic, automated, or semi-automated laser conservation method for historic glass. Complementary analytical techniques used include scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), confocal microscopy among others.