Towards Flexible Teamwork

Many AI researchers are today striving to build agent teams for complex, dynamic multi-agent domains, with intended applications in arenas such as education, training, entertainment, information integration, and collective robotics. Unfortunately, uncertainties in these complex, dynamic domains obstruct coherent teamwork. In particular, team members often encounter differing, incomplete, and possibly inconsistent views of their environment. Furthermore, team members can unexpectedly fail in fulfilling responsibilities or discover unexpected opportunities. Highly flexible coordination and communication is key in addressing such uncertainties. Simply fitting individual agents with precomputed coordination plans will not do, for their inflexibility can cause severe failures in teamwork, and their domain-specificity hinders reusability. Our central hypothesis is that the key to such flexibility and reusability is providing agents with general models of teamwork. Agents exploit such models to autonomously reason about coordination and communication, providing requisite flexibility. Furthermore, the models enable reuse across domains, both saving implementation effort and enforcing consistency. This article presents one general, implemented model of teamwork, called STEAM. The basic building block of teamwork in STEAM is joint intentions (Cohen & Levesque, 1991b); teamwork in STEAM is based on agents' building up a (partial) hierarchy of joint intentions (this hierarchy is seen to parallel Grosz & Kraus's partial SharedPlans, 1996). Furthermore, in STEAM, team members monitor the team's and individual members' performance, reorganizing the team as necessary. Finally, decision-theoretic communication selectivity in STEAM ensures reduction in communication overheads of teamwork, with appropriate sensitivity to the environmental conditions. This article describes STEAM's application in three different complex domains, and presents detailed empirical results.Comment: See http://www.jair.org/ for an online appendix and other files accompanying this articl

Review of Mobile tower radiation effects on Human and Mitigation techniques

All over the world there has been rapid increase in the mobile phone users . mobile phones are popular as they permit people to make and maintain constant and continuous communication without affecting their liberty of lifestyle . As usage of mobile phone is increasing, demand for seamless service is also gets increase and it puts pressure on the service provider . for fulfilling this demand supporting infrastructure is required .To strengthen infrastructure , service provider requires to install more mobile phone tower . Enormous installation of the mobile phone tower throughout the world raised the health concern of high electromagnetic radiation in the area near to these towers. This brings forward the need to revise the radiation level, their impact on the public health and mitigation techniques for radiations . DOI: 10.17762/ijritcc2321-8169.15024

THE SINGLE INDEX MARKET MODEL IN AGRICULTURE

This study illustrates the differences in empirical results due to data measurements and estimating procedures when applying the single index market model in agriculture. Gross and net return betas along with systematic and unsystematic risk proportions are estimated and found to be different. The stochastic coefficients model is used to show the difference in beta-risk estimates compared with the traditional fixed coefficients OLS procedure. A third estimating technique, weighted least squares/Prais Winsten method, is also proposed.Research Methods/ Statistical Methods,

Now I.T.’s “Personal”: Offshoring and the Shifting Skill Composition of the US Information Technology Workforce

We combine new offshoring and IT workforce micro-data to investigate how an increase in the offshore supply of IT workers has affected the composition of the US IT workforce. We find that at firms with offshore captive IT centers, the relative demand for onshore IT workers in occupations involving tasks that can be traded over computer networks, such as those requiring little personal communication or hands-on interaction with US-based objects, fell by about 8% over the last decade. By comparison, relative demand for workers in those occupations rose by about 3% in firms that were not offshoring. Our second finding is that hourly IT workers are more likely than full-time workers to be employed in occupations requiring tradable tasks, and that the relative demand for hourly IT workers is about 2-3% lower in offshoring firms. We discuss the implications of our findings for IT workers, policy makers, educators, and managers

Now IT\u27s Personal: Offshoring and the Shifting Skill Composition of the U.S. Information Technology Workforce

We combine new information technology (IT) offshoring and IT workforce microdata to investigate how the use of IT offshore captive centers is affecting the skill composition of the U.S. onshore IT workforce. The analysis is based on the theory that occupations involving tasks that are “tradable,” such as tasks that require little personal communication or hands-on interaction with U.S.-based objects, are vulnerable to being moved offshore. Consistent with this theory, we find that firms that have offshore IT captive centers have 8% less of their onshore IT workforce involved in tradable occupations; those without offshore captive centers have increased the proportion of onshore employment in these same occupations by 3%. In addition, we find that hourly IT workers (e.g., IT contractors) are disproportionately employed in tradable jobs, and their onshore employment is 2%–3% lower in firms with offshore captive centers. These findings persist after considering different measures of employment composition, including controls for human capital, firm performance, domestic outsourcing, and whether firms choose to build or buy software. Instrumental variables and corroborating regressions suggest that our estimates are conservative—the magnitude of the effect generally rises after accounting for reverse causality and measurement error

The Extroverted Firm: How External Information Practices Affect Innovation and Productivity

We gather detailed data on organizational practices and information technology (IT) use at 253 firms to examine the hypothesis that external focus—the ability of a firm to detect and therefore respond to changes in its external operating environment—increases returns to IT, especially when combined with decentralized decision making. First, using survey-based measures, we find that external focus is correlated with both organizational decentralization, and IT investment. Second, we find that a cluster of practices including external focus, decentralization, and IT is associated with improved product innovation capabilities. Third, we develop and test a three-way complementarities model that indicates that the combination of external focus, decentralization, and IT is associated with significantly higher productivity in our sample. We also introduce a new set of instrumental variables representing barriers to IT-related organizational change and find that our results are robust when we account for the potential endogeneity of organizational investments. Our results may help explain why firms that operate in information-rich environments such as high-technology clusters or areas with high worker mobility have experienced especially high returns to IT investment and suggest a set of practices that some managers may be able to use to increase their returns from IT investments.Massachusetts Institute of Technology. Center for Digital BusinessNational Science Foundation (U.S.) (Grant IRI-9733877

VALIDATED RP-HPLC METHOD FOR SIMULTANEOUS ESTIMATION OF CEFIXIME AND MOXIFLOXACIN IN COMBINED PHARMACEUTICAL DOSAGE FORM

Objective: To develop a simple, selective and rapid reversed phase high performance liquid chromatographic (HPLC) method for the analysis of cefixime and moxifloxacin in combined pharmaceutical dosage form as per ICH guidelines.Methods: The separation was achieved from C18 column at 350C with a mobile phase consisting of methanol: 0.05M heptane sulfonic acid sodium salt,0.5 ml THF and 0.5 ml TEA [75: 25 v/v]. pH-3.8 was adjusted with ortho phosphoric acid at a flow rate of 0.4 ml/min and the retention time was about 6.08 minutes for cefixime and 6.94 minutes for moxifloxacin. The method was selective to cefixime and moxifloxacin able to resolve the drug peak from formulation excipients.Results: The calibration curve was linear over the concentration range of 20-120 μg/ml (r2 = 0.999) for both drugs. The proposed method was found to be accurate and precise and linear within the desired range. The limit of detection (LOD) and limit of quantitation (LOQ)were calculated statically. Recoveries do not differ significantly from 100% which show there was no interference from the common excipient used in tablet formulation indicating accuracy and reliability of the method. The method was validated as per ICH guidelines and found to be accurate, precise and rugged. The method was validated in terms of linearity, accuracy, precision, specificity, LOD and LOQ.Conclusion: A novel, simple, selective and rapid reversed phase high performance liquid chromatographic (HPLC) method was developed for the analysis of cefixime and moxifloxacin in tablets. Hence,the method can be used for the routine analysis in various pharmaceutical industries.Â

Validation of in-house knowledge-based planning model for advance-stage lung cancer patients treated using VMAT radiotherapy

Objectives: Radiotherapy plan quality may vary considerably depending on planner's experience and time constraints. The variability in treatment plans can be assessed by calculating the difference between achieved and the optimal dose distribution. The achieved treatment plans may still be suboptimal if there is further scope to reduce organs-at- risk doses without compromising target coverage and deliverability. This study aims to develop a knowledge-based planning (KBP) model to reduce variability of volumetric modulated arc therapy (VMAT) lung plans by predicting minimum achievable lung volume-dose metrics. Methods: Dosimetric and geometric data collected from 40 retrospective plans were used to develop KBP models aiming to predict the minimum achievable lung dose metrics via calculating the ratio of the residual lung volume to the total lung volume. Model accuracy was verified by replanning 40 plans. Plan complexity metrics were calculated using locally developed script and their effect on treatment delivery was assessed via measurement. Results: The use of KBP resulted in significant reduction in plan variability in all three studied dosimetric parameters V5, V20 and mean lung dose by 4.9% (p = 0.007, 10.8 to 5.9%), 1.3% (p = 0.038, 4.0 to 2.7%) and 0.9 Gy (p = 0.012, 2.5 to 1.6Gy), respectively. It also increased lung sparing without compromising the overall plan quality. The accuracy of the model was proven as clinically acceptable. Plan complexity increased compared to original plans; however, the implication on delivery errors was clinically insignificant as demonstrated by plan verification measurements. Conclusion: Our in-house model for VMAT lung plans led to a significant reduction in plan variability with concurrent decrease in lung dose. Our study also demonstrated that treatment delivery verifications are important prior to clinical implementation of KBP models. Advances in knowledge: In-house KBP models can predict minimum achievable lung dose-volume constraints for advance-stage lung cancer patients treated with VMAT. The study demonstrates that plan complexity could increase and should be assessed prior to clinical implementation

Situation based strategic positioning for coordinating a team of homogeneous agents

. In this paper we are proposing an approach for coordinating a team ofhomogeneous agents based on a flexible common Team Strategy as well as onthe concepts of Situation Based Strategic Positioning and Dynamic Positioningand Role Exchange. We also introduce an Agent Architecture including a specifichigh-level decision module capable of implementing this strategy. Ourproposal is based on the formalization of what is a team strategy for competingwith an opponent team having opposite goals. A team strategy is composed of aset of agent types and a set of tactics, which are also composed of several formations.Formations are used for different situations and assign each agent a defaultspatial positioning and an agent type (defining its behaviour at several levels).Agents reactivity is also introduced for appropriate response to the dynamicsof the current situation. However, in our approach this is done in a way thatpreserves team coherence instead of permitting uncoordinated agent behaviour.We have applied, with success, this coordination approach to the RoboSoccersimulated domain. The FC Portugal team, developed using this approach wonthe RoboCup2000 (simulation league) European and World championshipsscoring a total of 180 goals and conceding none