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Human body in HCI is often seen as an actuator for issuing commands and providing input to digital systems. We present the concept of the body as a canvas, in which the body acts as both an actuator and a display for information. Body as a canvas creates an interaction loop where interaction with information causes changes in the body, which in turn changes the display of information. Our qualitative study using an on-body projection system in a public exhibition investigates this concept with regards to body characteristics, types of body input, interactions between multiple bodies, and comparison to other display technologies. Our findings show that body as a canvas create connectedness between the body and information. Finally, we discuss how body characteristics and appearances can complement the information, when the body acts as a canvas.
Virtual reality (VR) is now being designed and deployed in diverse sensitive settings, especially for therapeutic purposes. For example, VR experiences are used for diversional therapy in aged care and as therapy for people conditions such as phobias and post-traumatic stress. While these uses of VR offer great promise, they also present significant challenges. Given the novelty of VR, its immersive nature, and its impact on the user’s sense of reality, it can be particularly challenging to engage participants in co-design and predict what might go wrong when implementing these technologies in sensitive settings. This workshop provides a forum for researchers working in this emerging space to share stories about their experiences of designing and evaluating VR applications in settings such as aged care or mental health therapy. The workshop will develop a manifesto for good practice, outlining co-design strategies and ethical issues to consider when designing and deploying VR in sensitive settings.
Digital food technologies such as diet trackers, food sharing apps, and 'smart' kitchenware offer promising yet debatable food futures. While proponents suggest its potential to prompt efficient food lifestyles, critics highlight the underlying technosolutionism of digital food innovation and limitations related to health safety and data privacy. This workshop addresses both present and near-future digital food controversies and seeks to extend the existing body of Human-Food Interaction (HFI) research. Through scenarios and food- tech prototyping navigated by bespoke Digital Food Cards, we will unpack issues and suggest possible design approaches. We invite proposals from researchers, designers, and other practitioners interested in working towards a complex framework for future HFI research.
This paper presents findings from a small ethnographic study of children’s use of technology in family-friendly restaurants during dinnertime. We explore children’s use of a range of devices (iPad, mobile phone, laptop) in terms of the layout of the table, the juxtaposition of artefacts, the timing of interaction around eating, and the management of behaviour or ‘table manners’. Ultimately we argue that mobile technology use is adeptly managed by a range of actors – children, parents and restaurant staff – to facilitate a positive dining experience. Further we find that mobile technology use provides unforeseen opportunities for learning, game playing, and intergenerational interaction while allowing families to spend time together. Finally, we outline design considerations for restaurants and designers to better support children’s mobile technologies use in family-friendly restaurants.
[Conference Paper] Ferdous, H. S., Vetere, F., Davis, H., Ploderer, B., O’Hara, K., Comber, R., and Farr-Wharton, G. 2017. Celebratory Technology to Orchestrate the Sharing of Devices and Stories during Family Mealtimes. Accepted as a long paper in 35th Annual ACM Conference on Human Factors in Computing Systems (CHI '17). [pdf]
While the idea of “celebratory technologies” during family mealtimes to support positive interactions at the dinner table is promising, there are few studies that investigate how these technologies could be meaningfully integrated into family practices. This paper presents the deployment of Chorus - a mealtime technology that orchestrates the sharing of personal devices and stories during family mealtimes, explores related content from all participants’ devices, and supports revisiting previously shared content. A three-week field deployment with seven families shows that Chorus augments family interactions through sharing contents of personal and familial significance, supports togetherness and in-depth discussion by combining resources from multiple devices, helps to broach sensitive topics into familial conversation, and encourages participation from all members including children. We discuss implications of this research and reflect on design choices and opportunities that can further contribute to enhance the family mealtime experience.
This paper examines familial interactions, which are mediated through information and communication technologies, during domestic mealtimes. We seek to understand how technologies are used and negotiated amongst family members and the influence of technology on commensality. We conducted an observational study of six families. The findings showed how technologies are integrated into the mealtime activities. Our study identifies domestic circumstances where background technologies are raised to the foreground, visible devices are hidden, unwanted distractions become desired, and ordinary technologies are integrated into mealtime experiences. We identify four patterns of arrangement between technologies and family members during mealtimes, and we discuss how technologies contribute to mealtime satiety and commensality. Finally, we present implications of our findings and directions for technological advancements focusing on the social and celebratory nature of family mealtimes.
[Conference Paper] Ferdous, H. S., Ploderer, B., Davis, H., Vetere, F., O’Hara, K., Farr-Wharton, G., and Comber, R. 2016. TableTalk: Integrating Personal Devices and Content for Commensal Experiences at the Family Dinner Table. In Proceedings of the 2016 ACM International Joint Conference on Pervasive and Ubiquitous Computing (UbiComp '16), ACM. [pdf] [presentation]
This paper joins the ubiquitous computing scholarship that investigates the use of technologies in collocated shared settings like family mealtime. Family mealtimes are an important site for fostering togetherness, sharing everyday experiences, and nurturing familial ties. While technologies, especially television and personal devices are often criticized for disrupting the social aspects of mealtimes, they are widely available and commonly used nevertheless. In this paper, we explore this tension and present a novel system TableTalk, which transforms personal devices into a communal shared display on the table to enrich mealtime interactions and experience. Our field study shows that TableTalk does not undermine togetherness, but supports familial expectations and experiences by stimulating conversation, reminiscing, bonding, education, and socializing. We discuss how technology that is sensitive to the needs of family interactions can augment the commensal experience and reflect on design choices and opportunities that contribute, rather than disrupt, family mealtimes.
In this research, we investigate the everyday interactions of familial uses of technology around mealtimes and explore how family members configure the dinner space and the technologies within it. We seek to understand how technologies are used and negotiated amongst family members and the influence of technologies on the content and context of their interactions. Based on the current practices in families regarding such collocated use of both stationary and mobile networked communication devices, we identify four patterns of arranging technologies and family members during mealtimes and discuss design opportunities around it. Finally, we discuss about a novel design around collocated and collective use of personal and mobile technologies in the shared family mealtime space.
The last decade has seen the emergence of the social networking sites (SNS) and researchers are investigating the useful applications of this technology in various areas apart from its recreational value. Ubiquitous presence of SNS has enabled us to obtain customized information seamlessly from our acquaintance. There have been many works that analyzed the types and topics of questions people ask in these networks and why. Topics like what motivates people to answer such queries, how to integrate the traditional search engines, and SNS together are also well investigated. In this research, we focus on the use of this technology in underdeveloped parts of the world and the new doors it has opened for its inhabitants in terms of obtaining information. Analyzing 880 status messages collected from a widely used SNS, we have observed that, unavailability and inadequacy of information on web in developing countries play a significant role to motivate users using SNS for information retrieval. Based on a structured survey on 328 persons, we have tried to emphasize the differences between social search and traditional web search. Our statistical analysis finds the correlations among different relevant parameters and provides insight that one might require to consider while developing any application for SNS-based searching.
[Conference Paper] Ferdous, H. S., Ploderer, B., Davis, H., Vetere, F., and O'Hara, K. 2015. Pairing Technology and Meals: A Contextual Enquiry in the Family Household. In Proceedings of the 27th Annual Meeting of the Australian Special Interest Group for Computer Human Interaction (OzCHI '15), pp. 370-379, ACM. [pdf] [presentation]
Recent research about technology during mealtime has been mostly concerned with developing technology rather than creating a deeper understanding of the context of family mealtimes and associated practices. In this paper, we present a two-phase study discussing how the temporal, social, and food related features are intertwined with technology use during mealtimes. Our findings show how people differentiate technology usage during weekday meals, weekend meals, and among different meals of the day. We identify and analyse prototypical situations ranging from the use of arbitrary technologies while eating solitary, to idiosyncratic family norms and practices associated with shared technologies. We discuss the use of mealtime technology to create appropriate ambience for meals with guests and demonstrate how technology can be used to complement food in everyday meals and special occasions. Our findings make recommendation about the need for HCI research to recognize the contextual nature of technology usage during family mealtimes and to adopt appropriate design strategies.
In this research, we investigate the everyday interactions of familial uses of technology around mealtimes and explore how family members configure the dinner space and the technologies within it. We seek to understand how technologies are used and negotiated amongst family members and the influence of technologies on the content and context of their interactions. We aim to pay special attention to understand how our everyday technologies support our regular mealtimes as well as special occasions.
[Conference Paper, Short] McKay, D., Awori, K., and Ferdous, H. S. 2015. Three is a Crowd? Our Experience of Testing Large-Scale Social Software in a Usability Lab. In Proceedings of the 27th Annual Meeting of the Australian Special Interest Group for Computer Human Interaction (OzCHI '15), pp. 407-411, ACM. [pdf]
'In the wild' testing has been the cornerstone of HCI in past attempts to create large scale social software, such as conference software. Conversely mobile software is frequently tested in a lab environment, thus banishing typical context of use. In this paper we present our attempt at merging the two approaches for conference social software. We tested in the lab, but attempted to replicate some of the social context of field-based testing. We report our learnings and propose future research for this type of hybrid testing.
[Conference Paper] Ahmed, S. I., Jackson, S. J., Ahmed, N., Ferdous, H. S., Rifat, M. R., Rizvi, A. S. M., Ahmed, S., and Mansur, R. S. 2014. Protibadi: A Platform for Fighting Sexual Harassment in Urban Bangladesh. In Proceedings of the 32nd annual ACM conference on Human factors in computing systems (CHI '14), pp. 2695-2704, ACM. [pdf] [presentation]
Public sexual harassment has emerged as a large and growing concern in urban Bangladesh, with deep and damaging implications for gender security, justice, and rights of public participation. In this paper we describe an integrated program of ethnographic and design work meant to understand and address such problems. For one year we conducted surveys, interviews, and focus groups around sexual harassment with women at three different universities in Dhaka. Based on this input, we developed "Protibadi", a web and mobile phone based application designed to report, map, and share women's stories around sexual harassment in public places. In August 2013 the system launched, user studies were conducted, and public responses were monitored to gauge reactions, strengths, and limits of the system. This paper describes the findings of our ethnographic and design-based work, and suggests lessons relevant to other HCI efforts to understand and design around difficult and culturally sensitive problems.
[Conference Paper] Tasnim, M., Zaman, F., Ferdous, H. S., Galib, S., and Sharif, M. 2014. Towards Ubiquitous Learning Tools for Computer Aided Classroom in Developing Regions. In Proceedings of the 16th International Conference on Computer and Information Technology (ICCIT '13), pp. 320-325. IEEE. [pdf]
Education is recognized as one of the most powerful aspects for human development. Scope of education includes dispersal of knowledge, logical thinking, flourishing skills, refining habits, and sharing values. Accordingly, basic or primary education is a fundamental right for every citizen of a country. Studies provide sufficient evidence that individuals lacking primary education are incapable of making sensible choice about their own benefits in personal, social, and economic life. To ensure technology enhanced primary education for every citizen is yet a significant challenge for developing countries. A number of obstacles in the financial, technological, social, and political sector impede the way to exploit the blessings of modern technology in this sector. Keeping all these in mind, we have worked on a cost efficient tool to improve the learning experience in classrooms in developing regions. We have also designed some learning materials that can make learning exciting and enjoyable to the young learners. In this paper we focus on the existing problems in Primary Education system and the causes behind them. Later we present our cost effective equipment; application of which is believed to be effective in improving the scenario.
[Conference Paper] Ahmed, S., Anik, M. T. A., Tasnim, M., and Ferdous, H. S. 2013. Statistical Analysis and Implications of SNS search in Under-Developed Countries. In Proceedings of the 25th Annual Meeting of the Australian Special Interest Group for Computer Human Interaction (OzCHI '13), pp. 487-496, ACM. [pdf] [presentation]
Using Social Network Sites (SNS) as an information source has drawn the attention of the researchers for a while now. There have been many works that analyzed the types and topics of questions people ask in these networks and why. Topics like what motivate people to answer such queries, how to integrate the traditional search engines and SNS together are also well investigated. In this paper, we focus on a relevant but novel issue - how SNS search varies in developed and developing regions of the world and why. Analyzing 880 status messages collected from a widely used SNS, we have observed that, unavailability and inadequacy of information on web in developing countries play a significant role to motivate users using SNS for information retrieval. With established statistics of Internet usage, e-Governance, and our experimental data analysis, we have tried to emphasize the differences between social search and traditional web-search and provided insight that one might require to consider while developing any application for SNS based searching.
[Conference Paper] Ferdous, H. S., Ahmed, S., Anik, M. T. A., and Tasnim, M. 2013. SNS Search in Developing Countries: Linking the People to End Digital Division in Information Retrieval. In 5th International Conference on Computational Intelligence, Communication Systems and Networks (CICSyN '13), pp. 57-62, IEEE. [pdf]
Using Social Network Sites (SNS) as an information source has drawn the attention of the researchers for a while now. There has been many works that analyzed the types and topics of questions people ask in these networks and why. Topics like what motivate people to answer such queries, how to integrate the traditional search engines and SNS together are also well investigated. In this paper, we focus on a relevant but different issue - how SNS search varies in developed and developing regions of the world and why. With established statistics of Internet usage, e-Governance, and our experimental data collection, we have tried to emphasize the differences among them and provided insight that one might require to consider while developing any application for SNS based searching.
[Conference Paper] Islam, M. R., Rahaman, S., Hasan, R., Noel, R. R., Salekin, A., and Ferdous, H. S. 2013. A Novel Approach for Constructing Emulator for Microsoft Kinect XBOX 360 Sensor in the. NET Platform. In Proceedings of the 4th International Conference on Intelligent Systems Modeling & Simulation (ISMS '13), pp. 1-6. IEEE. [pdf]
The Microsoft Kinect sensor has brought a new era of Natural User Interface (NUI) based gaming and the associated SDK has provided access to its powerful sensors, which can be utilized in many ways, especially in research purposes. We have already seen its use in robotics, developing assistive technologies, and augmented reality, aside from gaming. Thousands of people around the world are playing with its built-in multimodal sensors, but still a complete emulator for the Kinect sensor device is lacking, thus requiring a physical device to do any experiments with it. In this work, we have come forward with a novel design of an emulator for the Kinect sensor and its implementation in the .NET platform using the Microsoft Kinect SDK. We have demonstrated the applicability of our system through detailed software design, code descriptions to incorporate this emulator in user's own code, and video demonstration of our proposed system.
Despite the ever-increasing popularity of mobile devices, text entry on such devices is becoming more of a challenge. Problems with traditional keypads primarily lie with placement of the letters alphabetically on the keys. This configuration, though very easy to remember, requires higher number of keystrokes and key jamming along with a limitation in flexibility of finger movement, as many frequent letters are not easily reachable by the thumb. Besides, users have to move their thumb extensively which also increases typing time and provides less comfort. Considering these issues, a novel solution to the problems is proposed in this paper, focusing on both the structure of suitable human finger movements and ordering of the letters on the keys. We took the basic Human Computer Interaction principles and general issues into consideration. Designs were found that have performance surpassing the traditional designs, while maintaining better usability. Simulations and a performance measurement of our proposed system have shown rapid lessening of key jamming by up to 51.38 percent, improvements in flexibility of finger movement by up to 7.31 percent, number of keystrokes by up to 29.99 percent and reduction of total distance while changing keys by up to 2.04 percent. In summary, this work represents an improved keypad layout for text entry on cell phones and other similar devices.
[Conference Paper] Ferdous, H. S., Ahmed, S., Islam, M. A., Kabir, M. H., and Ahmad, M. A. 2012. A Research Study on Determining the Effect of 3G Cellular Network on the Implementation of e-Governance in Bangladesh. In Proceedings of the IEEE Symposium on E-Learning, E-Management and E-Services (IS3E '12), pp. 1-6, IEEE. [pdf]
This research addresses the issues affecting e-Governance implementation in developing countries in consideration with implementation of the 3G mobile networks. Implementing e-Governance has always been a challenge either it is social, economical, or political. Besides this, there are many technological problems, which should be understood and met so that a user-accepted e-Governance system emerges. This research provides a quantitative investigation of e-Governance implementation problems with emphasis on analyzing quantitative data gathered in a survey using structured questionnaires that was generated on the basis of our theoretical study. Based on this results we provide a clear conception about those problems, which should be considered at the time of implementing e-Governance services in developing countries.
The distributed coordination function (DCF) of the IEEE 802.11 standard based medium access control has drawn significant interest from the researchers in the past decade. Many proposals of its performance analysis and modifications to remove its limitations are proposed. In this paper we are considering some recent proposals to make a detailed study of the performance comparison between DCF, CONTI, k-EC, and PREMA, which are various contention resolution schemes proposed in various independent researches. The criteria for performance comparison that we use are collision rate, throughput, and average delay between successful transmissions. Also, we consider queuing delay using an exponential on-off based unsaturated model for these protocols whose implementation and performance is consistent with the saturated mode used in the above contention schemes.
[Conference Paper] Monir, S., Rubya, S., and Ferdous, H. S. 2012. Rotation and Scale Invariant Posture Recognition using Microsoft Kinect Skeletal Tracking Feature. In Proceedings of the 12th International Conference on Intelligent Systems Design and Applications (ISDA '12), pp. 404-409, IEEE. [pdf]
Human posture identification for motion controlling applications is becoming more of a challenge. We present a posture classification system using skeletal-tracking feature of Microsoft Kinect sensor. Posture recovery is carried out by detecting the human body joints, its position, and orientation at the same time. Angular representation of the skeleton data makes the system very robust and avoids problems related to human body occlusions and motion ambiguities. The implemented system is tested on a class of relatively common postures comprising hundreds of human pose instances by different people, where our classifier shows an average accuracy of 94.9%, 96.7% and 96.9% for linear, exponential and priority based matching systems respectively.
[Conference Paper] Ferdous, H. S., Choudhury, F. M., Rifat, M. R., and Moutushy, S. 2012. Usability Analysis of e-Governance Services in Bangladesh — A Survey and Future directions. In Proceedings of the 15th International Conference on Computer and Information Technology (ICCIT '12), pp. 417-422. IEEE. [pdf]
This research addresses the issues affecting e-Governance implementation in Bangladesh in consideration with a detailed usability analysis and directions for future development. Implementing e-Governance has always been a challenge either it is social, economical, or political. Besides this, there are many technological problems, which should be understood and met, so that a user-accepted e-Governance system emerges. This research provides a quantitative investigation of e-Governance implementation problems with emphasis on analyzing quantitative data gathered in a survey using structured questionnaires that was generated on the basis of our theoretical study. Based on these results we provide a clear conception about those problems, which should be considered at the time of implementing e-Governance services in developing countries like Bangladesh.
Location Based Advertisement (LBA) has become today's most personal and direct marketing channel that provides customers more relevant information, personalized message, targeted offer about products and allows marketers to reach a specific target audience by creating campaigns. Location-based advertising (LBA) is a new form of advertising that integrates mobile advertising with location based services (LBS) to provide location-specific advertisements on consumer's devices. With the help of LBA, it is possible to target population at the right place and the right time. By taking advantage of a consumer's real world position, location based advertising delivers relevant ads for products and services. In this paper the features and usability of the application, “Location Based Intelligent Advertisement using OpenStreetMap” are explained and how this type of OpenStreetMap (OSM) based LBS application is effective for Bangladesh is discussed. The application helps the registered shop owners to introduce the offers to a consumer who is in close proximity to make them take those final steps to enter his store and let the consumer know what is around him with audio and map support. Additional feature of this application is for visually impaired people so that they can shop easily. We also focus on the benefits of using an open source map over a commercial one in this respect.
OpenStreetMap (OSM) is a world-wide campaign for developing open source maps. The prospect of such open source maps is very bright in commercial, educational and political points of views. With the burgeoning growth of cellular phones, the necessity of location based services is increasing day by day. Starting from the 3G mobile applications to cheap SMS-based services, we need maps everywhere. Various applications of digital maps are also seen in different national and international issues. Hence, OSM has been growing at a rapid pace in different parts of the world. However, it is a bit challenging task to develop this sort of voluntary efforts in the developing third world countries like Bangladesh. In this paper, we discuss the present conditions and initiatives taken for making OpenStreetMap a success in Bangladesh. Then we discuss about the various sectors that can be directly benefitted by the use of OSM in the context of developing countries like us and finally, we present the shortcomings and challenges that we face while developing OSM for this region.
With the ever-increasing popularity of cell phone devices, text based services on such devices is becoming more and more popular. Problems with traditional keypads primarily lie with the placement of the letters alphabetically on the keys. This configuration is comparatively easy for the users to remember but can greatly limit the flexibility of finger movement, as well as require a higher number of keystrokes and key jamming. In attempting to resolve these issues, a novel innovative solution is proposed here, focusing on both the structure of human finger movements and ordering of letters on the keys based on their frequency of use. Simulations and performance measurement of our represented system have shown rapid reduction in key jamming by up to 57 percent, improvements in flexibility of finger movement by up to 11.5 percent and reduction in number of keystrokes by up to 34 percent.
[Workshop Paper] Sabbir, A.S., Salim, K.M., Rafique, M.R.B., Rahman, M.O., Rahman, M.M., Bhuiyan, M.H., Ferdous, H.S., and Ahmed, S.I. 2011. Birth Record Communicator: A Pathway to Automated Health Data Acquisition System, in Proceedings of the Workshop on Interactive Systems in Healthcare (WISH '11), co-located with the American Medical Informatics Association’s (AMIA), Fall Symposium in Washington, DC, USA [pdf]
The problem of child malnutrition remains persistently high in the developing world, particularly among the ultra poor in the South Asia. Bangladesh, like most other countries in this region, does not have any database for birth records. Most of child births are still taking place at home with the help of a midwife and consequently no systematic records related to birth are maintained. The two most significant factors contributing to childhood malnutrition are low birth weight and premature delivery. In order to have a good understanding of the problem and develop appropriate intervention mechanisms we need a comprehensive database of birth records containing birth weights and gestation ages of the newborns. An application domain that makes use of wireless sensor network technology can be found in the above area focused on medical monitoring. This field ranges from monitoring patients in the hospital using wireless technology in order to remove the constraints of tethering patients to big, bulky, wired monitoring devices to monitoring people in their everyday lives to provide early detection and intervention for various types of disease. This paper discusses how we can automate the process of getting child birth weight from the remote places with the help of wireless technology and modern microcontroller devices.
[Workshop Paper] Hassan, A.Z., Zahed, B.T., Zohora, F.T., Moosa, J.M., Salam, T., Rahman, M.M., Ferdous, H.S., and Ahmed, S.I. 2011. Developing the Concept of Money by Interactive Computer Games for Autistic Children, in Proceedings of the IEEE Symposium on Multimedia (IEEE ISM) for The Sixth Workshop on Multimedia Technology for E-Learning (MTEL '11), IEEE. [pdf]
Autism is a general term used to describe a group of complex developmental brain disorders known as Pervasive Developmental Disorders (PDD). It is a life-long disability that prevents people from understanding what they see, hear, and sense. This results in severe problems with social relationships, communications, and behavior. Autism is typically diagnosed between the ages of two and six, although variations of ASD (Autism Spectrum Disorders) can sometimes be diagnosed earlier or later. Children with learning disability such as autism who have serious impairments with social, emotional and communication skills require high degree of personalization in using the educational software developed for them. In this paper we present a personalized game based on digital story-telling concept that helps the children of age ranging from 9 to 14 years old with autism to understand the use of money. It also teaches the autistic children the social behavior appropriate while shopping. The game is developed on BYOB (Build Your Own Block, an advanced offshoot of the game engine Scratch).
Multiuser dynamic OFDMA based IEEE 802.11 distributed coordination function (DCF) has received significant interest from the researchers in recent time. Though several proposals have been made, to the best of our knowledge, none of these have presented an analytical model for this kind of medium access control protocols for IEEE 802.11. This paper provides a simple, nevertheless, very accurate analytical model to estimate the performance characteristics of IEEE 802.11 DCF with OFDMA under the assumptions of ideal channel conditions and saturation load. Our model accounts for important system parameters like throughput, collision rate, transmission delay, average contention window size, average retry count and average time wasted in backoff. Analytical results are verified through extensive simulations.
In this paper, we discuss the challenges associated with integrating multiuser OFDMA in a single cell IEEE 802.11 based wireless ad hoc network and propose a new, dynamic and robust approach to improve it. Our new MAC, using OFDMA in the physical layer, can incorporate multiple concurrent transmissions or receptions in a dynamic manner and adjust the collision probability based on the traffic load when nodes are endowed with a single half-duplex radio only. Simulation results show that for moderate number of users, our system improves throughput by up to 20%, decreases collision in control messages by up to 45% and reduces the average delay by up to 18%.
In this paper, we discuss the problems associated with the present contention resolution mechanism of IEEE 802.11 DCF and present a new, dynamic and robust approach to improve it. Our new MAC, using OFDMA in the physical layer, can incorporate multiple concurrent transmissions or receptions in a dynamic manner and can adjust the collision probability based on the traffic load when nodes are endowed with a single half-duplex radio only. Simulation results show that our system improves throughput by up to 40 percent, reduces collision in control messages by up to 80 percent and reduces the average delay for data transmission by up to 20 percent.