Search

A major concern in the modern cement industry is considering how to minimize the CO2 footprint. Thus, cements based on belite, an impure clinker mineral (CaO)2SiO2 (C2S in cement chemistry notation), which forms at lower temperatures, is a promising solution to develop eco-efficient and sustainable cement-based materials, used in enormous quantities. The slow reactivity of belite plays a critical role, but the dissolution mechanisms and kinetic rates at the atomistic scale are not known completely yet. This work aims to understand the dissolution behavior of different facets of β-C2S providing missing input data and an upscaling modeling approach to connect the atomistic scale to the sub-micro scale. First, a combined ReaxFF and metadynamics-based molecular dynamic approach are applied to compute the atomistic forward reaction rates (RD) of calcium (Ca) and silicate species of (100) facet of β-C2S considering the influence of crystal facets and crystal defects. To minimize the huge number of atomistic events possibilities, a generalized approach is proposed, based on the systematic removal of nearest neighbors’ crystal sites. This enables us to tabulate data on the forward reaction rates of most important atomistic scenarios, which are needed as input parameters to implement the Kinetic Monte Carlo (KMC) computational upscaling approach. The reason for the higher reactivity of the (100) facet compared to the (010) is explained.

Cement clinkers containing mainly belite (β-C

Portlandite, as a most soluble cement hydration reaction product, affects mechanical and durability properties of cementitious materials. In the present work, an atomistic kinetic Monte Carlo (KMC) upscaling approach is implemented in MATLAB code in order to investigate the dissolution time and morphology changes of a hexagonal platelet portlandite crystal. First, the atomistic rate constants of individual Ca dissolution events are computed by a transition state theory equation based on inputs of the computed activation energies (Δ

Groundwater has become an important source of water to meet the increasing requirement for domestic, industrial, and agricultural needs. The study was formulated to assess the availability of groundwater resources in Selangor State, Malaysia. An integrated MIKE SHE and MIKE 11-based surface water–groundwater interaction model was developed to fulfill the study objectives. Model results illustrated that groundwater flows from the eastern part of the hilly region to the western part and ultimately discharges into the sea. The study also revealed that Sungai Langat, Sungai Klang, and Sungai Selangor receive water from groundwater and do not feed the groundwater. Approximate potential groundwater resources based on water balance study varies from 860–960 million liter per day (MLD), 630–690 MLD, 810–870 MLD to 630–690 MLD for Langat basin, Klang basin, Selangor basin, and Bernam basin, respectively. Impacts due to extreme dry condition showed that groundwater table declined about 0.5–3 m in most of the area. However, groundwater level for the major portion of Selangor State will drop to about 0–1 m for increased abstraction due to changed land-use pattern. Study findings may be used for a holistic and comprehensive management of groundwater resources for sustainable development in Selangor State, Malaysia.

In the rush towards urbanization as well as with emerging consumption, many developing countries have witnessed the overflow of waste and depletion of the inexhaustible natural resources at an alarming rate. As wastes are the outgrowth of the urban system, the urban dynamics influence the quantity, types and management of waste. The purpose of this study is to estimate the amount of the generated wastes from 2002 to 2017 with the urban growth of Sylhet city and implement the 3R (recycling, reuse, refuse) strategy conceptually for maximizing resource recovery and reducing landfilling. In this study, solid waste generation and it’s composition is estimated by collecting data through interviews encompassing 300 units from the representative areas and direct field survey. Correlation test between population and solid waste has been performed to measure the strength of association. The result indicated that, in 15 years, waste generation has increased 170 tons which calls for better management. From the study it is shown that about 72.46% (188.396 tons) of the waste can be minimized by executing 3Rs leaving only 27.54% to be dumped into landfill. It is evident that, implementation of the 3Rs will have a profound impact to protect the environment.

Summary In this work a novel framework for modeling role and task allocation in Cooperative Heterogeneous Multi‐Robot Systems (CHMRSs) is presented. This framework encodes a CHMRS as a set of multidimensional relational structures (MDRSs). This set of structure defines collaborative tasks through both temporal and spatial relations between processes of heterogeneous robots. These relations are enriched with tensors which allow for geometrical reasoning about collaborative tasks. A learning schema is also proposed in order to derive the components of each MDRS. According to this schema, the components are learnt from data reporting the situated history of the processes executed by the team of robots. Data are organized as a multirobot collaboration treebank (MRCT) in order to support learning. Moreover, a generative approach, based on a probabilistic model, is combined together with nonnegative tensor decomposition (NTD) for both building the tensors and estimating latent knowledge. Preliminary evaluation of the performance of this framework is performed in simulation with three heterogeneous robots, namely, two Unmanned Ground Vehicles (UGVs) and one Unmanned Aerial Vehicle (UAV).

This paper presents a wearable emergency response system for women based on Internet of things (IoT) by considering the viewpoint of Bangladesh. Different type of sexual violence against women are happened all over the Bangladesh. Rape is the most common type of violence against women in recent days in our country. Rape is increasing rapidly. Victims of rape are not interested to file a legal complain against rapist, due to social barriers. Sometimes they feel shy and uncomfortable. In this regard a connected wearable device is introduced. This wearable device will established a communication among women with their family members, police station and nearby volunteer people. In extreme condition, a victim can able to make a help request directly to police station as well as nearby volunteer people (eager to help) and their family members by simply pressing a button of the proposed device. The conceptual design and implementation of the wearable device is discussed on this paper.

This paper describes a lightweight obstacle detection system for Micro Aerial Vehicles (MAVs). This system is composed of multiple infrared (IR) proximity sensors interconnected through an open source development board. Standard methods for obstacle detection for UAVs commonly rely on sensory systems, such as, cameras and range finders. These sensors are usually very expensive. Moreover, their use is limited by both the payload and the computational resources available on the vehicle. By contrast, proximity sensors are cheap as well as lightweight. They can allow to detect the presence of objects in the nearby without any physical contact. We installed the system on a Parrot AR. Drone. This drone is a MAV with low payload capacity. Experiments in both simulation and real environments have been performed to test the effectiveness of our system.

This paper presents a monitoring/tracking system for water passenger vehicle such as vessels or ferries. Bangladesh is a land of rivers. Each and every year peoples die due to accidents in water vehicles. The rescue teams are unable to reach there on time due to the communication barriers which causes huge damages in life. On the other hand, some captains of ferries/vessels do not maintain the weather notifications as well as overload the vessels before leaving the terminal, which are the main reasons for accident listed by BIWTA. In this regard, we have proposed real time monitoring/tracking system for water vehicle. The system (continuously) monitors the status(such as geo-location, load information, the orientation etc.) of the vehicles and sends reports to the ground/control station. As a result, the ground station will always be aware of vehicle status. The details design and implementation of proposed system are also discussed in this paper. The proposed system increases the safety by reducing the number/chances of accidents.

Current water quality monitoring system is a manual system with a monotonous process and is very time-consuming. This paper proposes a sensor-based water quality monitoring system. The main components of Wireless Sensor Network (WSN) include a microcontroller for processing the system, communication system for inter and intra node communication and several sensors. Real-time data access can be done by using remote monitoring and Internet of Things (IoT) technology. Data collected at the apart site can be displayed in a visual format on a server PC with the help of Spark streaming analysis through Spark MLlib, Deep learning neural network models, Belief Rule Based (BRB) system and is also compared with standard values. If the acquired value is above the threshold value automated warning SMS alert will be sent to the agent. The uniqueness of our proposed paper is to obtain the water monitoring system with high frequency, high mobility, and low powered. Therefore, our proposed system will immensely help Bangladeshi populations to become conscious against contaminated water as well as to stop polluting the water. Konferensartikel i tidskrift

To date, the effects of Bambusa tulda on stem cells have not been thoroughly assessed. The present study aimed to evaluate the effects of Bambusa tulda extract on the morphology and proliferative potential of human mesenchymal stem cells derived from the gingiva. The stem cells were cultured in a growth medium in the presence of Bambusa tulda methanolic extract (BBT) at concentrations ranging from 0.001 to 1%. Evaluation of cell morphology and cellular proliferation as well as immunofluorescent assays for collagen I were performed on days 1, 3, 5 and 7. Stem cells in the control group displayed a fibroblast-like morphology, and BBT treatment did not produce any noticeable morphological changes. However, application of 1% BBT produced a significant increase in cell proliferation. BBT, particularly at the concentration of 1%, also caused a noticeable increase of collagen I expression at day 1 and day 3. Based on these findings, it was concluded that BBT exerted beneficial effects on the proliferation of mesenchymal stem cells and enhanced collagen I expression at early time points.

The popularity of Internet of Things is increasing day by day in the area of remote monitoring system. The remote monitoring systems include, vehicle or assets monitoring, kids/pets monitoring, fleet management, parking management, water and oil leakage, energy grid monitoring etc. In this paper, we have proposed an intelligent patient monitoring system for monitoring the patients' health condition automatically through sensors based connected networks. Several sensors are used for gathering the biological behaviors of a patient. The meaningful biological information are then forwarded to the IoT cloud. The system is more intelligent that can able to detect the critical condition of a patient by processing sensors data and instantly provides push notification to doctors/nurses as well as hospital in-charge personal. The doctors and nurses get benefited from this system by observing their corresponding patients remotely without visiting in person. Patients' relatives can also get benefited from this system with limited access.

With the emergence of new technology and innovations, people are searching smarter ways to protect/monitor their properties remotely. In accordance to that, at present GPS based tracking system is frequently used in vehicle tracking, children/pet tracking, aircraft tracking, any personal belongings tracking, fleet management and so on. This paper introduces a Smart Anti-Theft Vehicle System based on Internet of Things (IoT) for monitoring the movement of any equipped vehicle from anywhere in real time. At the implementation of this system, Global Positioning System (GPS), Global System for Mobile Communication (GSM)/General Packet Radio Service (GPRS) and Microcontrollers are used to enable users for monitoring their vehicles in a convenient manner. This system provides the access to check the movement and control (emergency stop by closing the fuel line) vehicles remotely by using mobile application. The hardware prototype of the proposed system and the user application for monitoring and controlling vehicles are presented in this paper.

This paper presents our on-going research of comparing the composition of web services by Petri nets and BPEL. We model the transaction of a Car Broker web Service using both BPEL and Petri nets examining the expressiveness of both languages. In the reminder of the paper, Section III gives an overview of the Petri nets and its constructs. Section V first briefly describes our case study web service and then model the web service in both BPEL and Petri nets. For brevity only an abstract version of Car Broker web Service is modeled in this paper. Finally, we conclude our paper and outline our future

The study describes the effects of depulping the fruits and soaking the seeds of Terminalia belerica Roxb. on seed germination and seedling growth in nursery condition. Around half of the freshly collected fruits of T. belerica were depulped by rotting the fleshy pulp in water. Depulped seeds or intact fruits were dried in sun following storage in airtight container. Effects pre-sowing treatments were explored by soaking the dry intact fruits or depulped seeds in cold water for 0, 24, 48 and 72 h and sowed in polybags filled with soil mixed with decomposed cow dung. The study revealed that depulping of fruits and soaking the seeds significantly enhanced the seed germination and seedling growth performance in nursery condition. The fastest seed germination was observed in depulped seeds soaked in cold water for 72 h (DT3) and slowest germination was in intact fruits without treatment (IT0). The highest germination percentage (93) was observed in depulped seeds soaked in cold water for 48 h (DT2) followed by 85.6% in depulped seeds soaked in water for 24 h (DT1), which was significantly higher than the other treatments including the control (36.7). Although growth parameters such as shoot length, root length, total height, leaf number, leaf area and collar diameter of the seedlings were maximum in the seedlings developed through DT3, the vigor index was maximum in DT2 and minimum in IT0. Total dry mass per seedling was also maximum in the seedlings developed from the treatment DT3. Considered the imbibition period, germination percentage, growth performance including vigor index and total biomass produced per seedling, depulping the fruits and soaking the dry seeds in cold water for 48 h was recommended for obtaining maximum seed germination and seedling growth performance.

Selection of tender is a multi-criteria decision making process in which project performance is influenced by time, cost and quality. The appropriate tender selection can ensure a smooth delivery process and eliminate several complexities during construction. In this paper, the evidential reasoning (ER) approach which is capable of processing both quantitative and qualitative data is applied to find out the influencing factors as a means of solving the tender evaluation problem. The process of building a multiple criteria decision model of a hierarchical structure is presented, in which both quantitative and qualitative information is represented in a unified manner. By using a case study of Bangladesh the tender evaluation problem is then fully investigated using the ER approach. Finally we show the rank of influencing factors of best tender..

Mobile payments are a natural evolution of e-payment schemes that will facilitate mobile commerce. A mobile payment or m-payment may be defined, as any payment where a mobile device is used to initiate, authorize and confirm an exchange of financial value in return for goods and services. Mobile devices may include mobile phones, PDAs, wireless tablets and any other device that connect to mobile telecommunication network and make it possible for payments. In Bangladesh, several private banks (Dutch-Bangla Ltd, Islami Bank Ltd, Trust Bank Ltd and Others) introduced mobile banking. The BRAC Bank-initiated mobile banking service, “bKash”, is at present the country's leading service-provider in mobile banking. This paper present a new m-payment system called “mCard” replacing existing Credit or Debit or ATM card and includes some feature of mobile banking (except money transfer to remote area).

Web services technology provides a platform on which we can develop distributed services. The interoperability among these services is achieved by various standard protocols. In recent years, several researches suggested that process algebras provide a satisfactory assistance to the whole process of web services development. Business transactions, on the other hand, involve the coordination and interaction between multiple partners. With the emergence of web services, business transactions are conducted using these services. The coordination among the business processes is crucial, so is the handling of faults that can arise at any stage of a transaction. BPEL models the behavior of business process interaction by providing a XML based grammar to describe the control logic required to coordinate the web services participating in a process flow. However BPEL lacks a proper formal description where the composition of business processes cannot be formally verified. Process algebra, on the other hand, facilitates a formal foundation for rigorous verification of the composition. This paper presents a comparison of web service composition between BPEL and process algebra, cCSP., Comment: 6 pages, 4 figures, Advanced Computer Science Applications and Technologies (ACSAT), 2012 International Conference on

This paper describes an integrated approach of site suitability mapping and ranking of the most suitable sites, for the implementation of Managed Aquifer Recharge (MAR) projects, using spatial multicriteria decision analysis (SMCDA) techniques and mathematical modelling. The SMCDA procedure contains constraint mapping, site suitability analysis with criteria standardization and weighting, criteria overlay by analytical hierarchy process (AHP) combined with weighted linear combination (WLC) and ordered weighted averaging (OWA), and sensitivity analysis. The hydrogeological impacts of the selected most suitable sites were quantified by using groundwater flow and transport modelling techniques. Finally, ranking of the selected sites was done with the WLC method. The integrated approach is demonstrated by a case study in the coastal aquifer of North Gaza. Constraint mapping shows that 50% of the total study area is suitable for MAR implementation. About 25% of the total area is “very good” and 25% percent is “good” for MAR, according to the site suitability analysis. Six locations were selected and ranked against six representative decision criteria. Long term (year 2003 to year 2040) groundwater flow and transport simulations were performed to quantify the selected criteria under MAR project operation conditions at the selected sites. Finally, the suitability mapping and hydrogeological investigation recommends that the location of the existing infiltration ponds, constructed near the planned North Gaza Wastewater Treatment Plant (NGWWTP) is most suitable for MAR project implementation. This paper concludes that mathematical modelling should be combined with the SMCDA technique in order to select the best location for MAR project implementation. Besides MAR project implementation, the generalised approach can be applicable for any other water resources development project that deals with site selection and implementation.

Primary education is one of the important social sectors in the developing countries. It plays a gigantic role in promoting the social development of the concerned countries. More specifically, not the only education but the quality primary education which depends on such factors will contribute a lot for its smooth acceleration. In primary education, if the quality will maintain then automatically all the problems in primary education i.e. enrollment, completion, drop-out and so on will be robotic and gradually solved. The improvement primary education is influenced by both multiple qualitative and quantitative factors. This paper presents evidential reasoning(ER) approach to find out significant factors that are aggregated in assessment of performance of primary education. A case study of Dhaka, Chittagong, Rajshahi and Khulna districts in Bangladesh is provided to illustrate the implementation process of the ER approach for finding strong factors of primary education. For that reason, firstly we assess the performance of four districts then we determine the weakness and strength of specific factors of particular district. In this paper we also show the relation of lowest or best performing districts to its specific factors.

Relay networks achieve high performance by utilizing cooperation between nodes which can classified as multi-hop networks and cooperative MIMO relaying networks. Cooperative diversity is a transmission technique to overcome fading, multipath and inter-channel interference. As an important part of "spatial diversity" systems, cooperative diversity involving multi hop data relays is a solution to improve propagation performance, expanding coverage and enhancing system capacity in such wireless environments. In a cooperative diversity system, the "third party" mobile devices acting as relays to help the main transmission link for improving the performance such as bit error rate (BER), data rate, coverage. This paper is a study of analyzing the system performance for MIMO-Relaying MIMO in different wireless channel and results show the better performance of cooperative communication.