Formulating layered adjustable autonomy for unmanned aerial vehicles

Purpose - In this paper, we propose a Layered Adjustable Autonomy (LAA) as a dynamically adjustable autonomy model for a multi-agent system. It is mainly used to efficiently manage humans and agents share control of autonomous systems and maintain humans’ global control over the agents. Design/Methodology/Approach - We apply the LAA model in an agent-based autonomous Unmanned Arial Vehicle (UAV) system. The UAV system implementation consists of two parts, software, and hardware. The software part represents the controller and the cognitive and the hardware represents the computing machinery and the actuator of the UAV system. The UAV system performs three experimental scenarios of dance, surveillance and search missions. The selected scenarios demonstrate different behaviors in order to create a suitable test plan and ensure significant results. Findings - The results of the UAV system tests prove that segregating the autonomy of a system as multidimensional and adjustable layers enables humans and/or agents to perform actions in a convenient autonomy levels. Hence, reducing the adjustable autonomy drawbacks of constraining the autonomy of the agents, increasing humans’ workload and exposing the system to disturbances. Originality/value - The application of the LAA model in a UAV manifests the significance of implementing dynamic adjustable autonomy. Assessing the autonomy within three phases of agents run cycle (task-selection, actions-selection, actions-execution) is an original idea that aims to direct agents’ autonomy towards performance competency. The agents’ abilities are well exploited when an incompetent agent switches with a more competent on

Changes in chemical properties of an Ultisol as affected by palm oil mill effluent application

An experiment was conducted to determine the effects of palm oil mill effluent (POME) application on soil chemical properties. The POME was incorporated into the top 0-30 cm of Batang Merbau soil, an Ultisol. POME was applied at 0, 5, 10, 20, and 40 t ha-1, both in the presence and absence of 2 t ground magnesian limestone (GML). A succeeding crops of maize and groundnut were planted. The results of the experiment showed that POME application up to the rate of 40 t ha-1 did not significantly change the topsoil pH and exchangeable calcium (Ca), magnesium (Mg), and aluminum (Al). The addition of POME improved the soil fertility, which resulted in an increase of maize yield. The Ca and Mg from the POME accumulated in the topsoil, being held by the negative charge present on the exchange complex. The beneficial effects of POME and/or GML application lasted for about 3 years. The study indicated that application of POME together with GML is a good agronomic option to alleviate soil acidity in Ultisol for maize production

Longevity of ground magnesium limestone applied to an Ultisol

Soils in the upland areas of Malaysia are mostly weathered (Ultisols and Oxisols), having high aluminum (Al), but calcium (Ca) and/or magnesium (Mg) deficient. Magnesium limestone is available in large quantities in Malaysia and is frequently being used to alleviate acidity in the upland soils. This study aimed at assessing the longevity of the limestone applied to an highly weathered acid soil under conditions prevailing in the tropics. The experiment consisted of two phases; in the first phase the plots were treated with various rates of lime, while in the second phase some plots were left as residual treatments. The results of the study showed that an acid Ultisol of Malaysia can be ameliorated by annual limestone application of 1 t ha-1 for maize (Zea mays L.) production. The beneficial effects of liming with ground magnesium limestone (GML) at 4 t ha-1 were observed for about eight years. The critical soil pH and exchangeable Al for maize production were found to be 5 and 0.7 cmol(c)kg-1 soil, respectively. The Ca and Mg from the limestone were mostly found in the topsoils because of the increase in cation exchange capacity (CEC) resulting from the pH increase

A Framework for Research Supervision

One of the main challenges that are encountered in research development is the management of research activities. Supervisors often have difficulties in managing schedules, issues and supervision of different research activities. This is compounded by students’ poor research skills. Consequently, in this paper, we propose a knowledge management framework to point out, track, and monitor various research supervision activities. The proposed framework consists of two layers, abstract and detail. The abstract layer consists of six stages which are; basement stage, review stage, data collection stage, data analysis stage, development stage, and testing and validation stage. These stages, according to our framework, are mandatory; in other words, any research must go through the stages. To complete the task of each stage, a number of steps are defined, which constitute the detail layer. A supervisor is able to pick up appropriate steps (and not all suggested steps) from the detail layer since the complexity varies from one research to another. We discuss the results of our findings in conceiving the framework. Keywords: research development, development stage, research activities, supervision managemen

An Automated Negotiation-based Framework via Multi-Agent System for the Construction Domain

In this paper, we propose an automated multi-agent negotiation framework for decision making in the construction domain. It enables software agents to conduct negotiations and autonomously make decisions. The proposed framework consists of two types of components, internal and external. Internal components are integrated into the agent architecture while the external components are blended within the environment to facilitate the negotiation process. The internal components are negotiation algorithm, negotiation style, negotiation protocol, and solution generators. The external components are the negotiation base and the conflict resolution algorithm. We also discuss the decision making process flow in such system. There are three main processes in decision making for specific projects, which are propose solutions, negotiate solutions and handling conflict outcomes (conflict resolution). We finally present the proposed architecture that enables software agents to conduct automated negotiation in the construction domain

An Investigation on Measuring Accuracy of Explicit Knowledge Sources in Universities

At present, e-libraries contain huge volumes of articles that may be irrelevant or inaccurate to academics’ research areas. The academics may spend extensive time and efforts to retrieve knowledge contents from these articles. Thus, universities need to manage their articles’ libraries effectively to deliver the most suitable explicit contents based on academics’ research areas. Consequently, in this paper, we identify potential factors that could contribute to candidate relevant and accurate articles that meet employees need. These factors work on measuring the accuracy of articles to identify the most relevant articles from the huge resources of online articles. Therefore, the search time and efforts could be reduced through classifying articles based on the contents’ knowledge using practical measurement factors. To address the objectives of this research, quantitative and qualitative studies are made to collect data using questionnaire survey and interview of experts in knowledge management. The results of the data analysis are used to identify the relevant factors and to compute the accuracy of articles based on these factors. Keywords: knowledge management, explicit knowledge, knowledge measurement

A Simple, Precise and Cost Effective PTFE Container Design Capable to Work in Domestic Microwave Oven

Starting from the first application of a microwave oven for sample preparation in 1975 for the purpose of wet ashing of biological samples using a domestic microwave oven, many microwave-assisted dissolution vessels have been developed. The advanced vessels are armed with special safety valve that release the excess of pressure while the vessels are in critical conditions due to applying high power of microwave. Nevertheless, this releasing of pressure may cause lose of volatile elements. In this study Teflon bottles are designed with relatively thicker wall compared to commercial ones and a silicone based polymer was used to prepare an O-ring which plays the role of safety valve. In this design, eight vessels are located in an ABS holder to keep them stable and safe. The advantage of these vessels is that they need only 2 mL of HNO3 and 1mL H2O2 to digest different environmental samples, namely, sludge, apple leave, peach leave, spinach leave and tomato leave. In order to investigate the performance of this design an ICP-MS instrument was applied for multi elemental analysis of 20 elements on the SRM of above environmental samples both using this design and a commercial microwave digestion design. Very comparable recoveries were obtained from this simple design with the commercial one. Considering the price of ultrapure chemicals and the amount of them which normally is about 8-10 mL, these simple vessels with the procedures that will be discussed in detail are very cost effective and very suitable for environmental studies

A Simple, Precise and Cost Effective PTFE Container Design Capable to Work in Domestic Microwave Oven

Starting from the first application of a microwave oven for sample preparation in 1975 for the purpose of wet ashing of biological samples using a domestic microwave oven, many microwave-assisted dissolution vessels have been developed. The advanced vessels are armed with special safety valve that release the excess of pressure while the vessels are in critical conditions due to applying high power of microwave. Nevertheless, this releasing of pressure may cause lose of volatile elements. In this study Teflon bottles are designed with relatively thicker wall compared to commercial ones and a silicone based polymer was used to prepare an O-ring which plays the role of safety valve. In this design, eight vessels are located in an ABS holder to keep them stable and safe. The advantage of these vessels is that they need only 2 mL of HNO3 and 1mL H2O2 to digest different environmental samples, namely, sludge, apple leave, peach leave, spinach leave and tomato leave. In order to investigate the performance of this design an ICP-MS instrument was applied for multi elemental analysis of 20 elements on the SRM of above environmental samples both using this design and a commercial microwave digestion design. Very comparable recoveries were obtained from this simple design with the commercial one. Considering the price of ultrapure chemicals and the amount of them which normally is about 8-10 mL, these simple vessels with the procedures that will be discussed in detail are very cost effective and very suitable for environmental studies