Vedran Podobnik | University of Zagreb (original) (raw)

Papers by Vedran Podobnik

Lecture Notes in Computer Science, 2006

Applications and Systems, 2008

... Therefore, recent approaches to the discovery processes are increasingly grounded on mechanis... more ... Therefore, recent approaches to the discovery processes are increasingly grounded on mechanisms which exploit the semantics of resource descriptions (“intelligent discovery”) (Colluci, Noia, Sciascio, Donini, &amp; Mongiello, 2005; Keller, Lara, Lausen, Polleres, &amp; Fensel, 2005 ...

Lecture Notes in Computer Science, 2008

In order to increase profit and remain competitive on the telecommunication market, telcos must i... more In order to increase profit and remain competitive on the telecommunication market, telcos must introduce new types of services. Nowadays, basic mobile services are insufficient for an average user: advanced services include combination of entertainment and information content, and as such require greater personalization. The future of mobile communications is directed towards creating systems aware of user preferences, mobile device capabilities, and communication context. Such systems will enable telcos to use new approaches in service provisioning (e.g., dynamic user group formation can enhance provisioning of group-oriented services). This paper presents how using Semantic Web and software agent technologies can help improving telecommunication processes: we propose AMiGO-Mob middleware for enhancing group-oriented mobile service provisioning.

Multimedia applications executed on mobile devices allow users to be present and communicate with... more Multimedia applications executed on mobile devices allow users to be present and communicate with other users, anywhere and anytime, through wide area cellular networks, wireless local area networks (WLAN), or fixed networks. In order to enable ubiquitous personalized services, communication systems should allow users to specify their context, or their mobile devices and network infrastructures should automatically sense their context and offer enhanced service provisioning solutions. In this paper, we propose an agent-based solution that supports context-aware provisioning of IP multimedia subsystem (IMS)-enabled ubiquitous services. Using agent technology, multimedia communication, controlled by SIP and enriched with context-related events delivered by SIP’s event mechanism, can be seamlessly provisioned, taking into account not only mobility issues and context-awareness, but also the semantics of exchanged events. This paper proposes a multi-agent system that will enable users to consume context-aware ubiquitous services in a seamless (i.e., automated) way, providing optimal provisioning of SIP-based multimedia services according to user preferences.

In this article we propose a novel approach, enabled by software agents, in mobile service provis... more In this article we propose a novel approach, enabled by software agents, in mobile service provisioning process: energy-efficient collaborative downloading. The main idea is that mobile users, represented with their agents and corresponding profiles, interested in the same content download some parts directly from a service server and others afterwards locally exchange among themselves to reduce overall energy consumption. Collaborative downloading is formed as an auction where mobile users’ agents compete to determine which parts of a requested content to download directly from the service server and which to exchange with other users. Our main motivation for conceiving collaborative downloading was to lower the overall energy consumption of users’ mobile devices. Simulation results demonstrate that the proposed innovation can save up to 75% of the energy of mobile devices’ batteries.

2014 22nd International Conference on Software, Telecommunications and Computer Networks (SoftCOM), 2014

Proceeding of 12th International Conference on Telecommunications (ConTEL 2013), 2013

Many companies diligently establish their presence on Social Networking Services (SNSs) as they r... more Many companies diligently establish their presence on Social Networking Services (SNSs) as they recognize Social Media Marketing (SMM) will be the next “holy grail of marketing”. However, yet the true value of SMM remains unclear because marketing based on social networking still defines its best practices and metrics. This paper provides a small step towards understanding how to unlock a potential of SMM through analysis of Key Performance Indicators (KPIs) for the flagship SMM platform Facebook. The case study of five largest Premier League brands analyses relationships among Facebook SMM KPIs and identifies several interesting connections. The most important managerial implication of our analysis suggests that the number of Facebook fans, although often criticized as the relevant SMM metric, is the most important SMM KPI.

Book Chapters by Vedran Podobnik

Service-Oriented Computing: Agents, Semantics, and Engineering

Agent and Multi-Agent Systems: Technologies and Applications

Knowledge-Based and Intelligent Information and Engineering Systems

In this article we propose an agent-based solution for enabling paradigm shift from CRM (Customer... more In this article we propose an agent-based solution for enabling paradigm shift from CRM (Customer Relationship Management) to CMR (Customer-Managed Relationship). Namely, Telco Agent is a software agent which represents telecom operator in interactions with its customers. Customers provide Telco Agent with their profiles and afterwards Telco Agent uses its mechanisms for semantic matchmaking of customer profiles and creation of customer social network to facilitate autonomous CMR.

Transactions on Computational Collective Intelligence II

Today, telecom operators face a threefold challenge: a social challenge dealing with the evolutio... more Today, telecom operators face a threefold challenge: a social challenge dealing with the evolution of the consumer lifestyle, a technological challenge dealing with ever changing ICT trends and a business challenge dealing with the need for innovative business models. This paper introduces an idea of group-oriented services, a special type of personalized telecom services, as a possible solution for all three of these challenges. A proof-of-concept service, called Agent-Based Mobile Content Brokerage, is presented and elaborated with the aim to demonstrate a shift towards consumer-managed relationships, a novel provisioning paradigm within the telecom industry.

Agent and Multi-Agent Systems: Technologies and Applications

Social network services such as Facebook, MySpace or Twitter support more or less permanent socia... more Social network services such as Facebook, MySpace or Twitter support more or less permanent social relationships, where user interaction takes place via fixed or mobile access to the Internet. However, in many situations social relationships are ad-hoc (i.e., set up by (mobile) users located in a limited geographical area during a certain period in time). To effectively support this kind of social relationships, we propose an extension of basic social networking model – the ad-hoc social networking. This paper defines the model for ad-hoc social networking, describes functionalities and architecture of a platform for ad-hoc social networking and explains why software agents are opportune technology for platform implementation. Finally, paper presents several applications of ad-hoc social networking.

Agent and Multi-Agent Systems. Technologies and Applications

With intense increase in number of competing service providers in the information and communicati... more With intense increase in number of competing service providers in the information and communication sector, companies must implement mechanisms for forecasting consumer interest in new services. Common growth models provide the mechanisms for modelling and predicting acceptance of a certain service. However, they have two shortcomings: i) limited precision; and ii) a short, but yet existing, time delay. By using semantic reasoning for detecting similarities between services already on a market and ones that are just to be introduced, it is possible both to increase forecasting precision and eliminate the time delay caused by the need to collect a certain amount of data about the new service before a prediction can be made. The proposed semantic-aware prediction model is elaborated on a case of forecasting YouTube clip popularity.

Agent-Mediated Electronic Commerce. Designing Trading Strategies and Mechanisms for Electronic Markets

Sponsored search is a popular form of targeted online advertising and the most profitable online ... more Sponsored search is a popular form of targeted online advertising and the most profitable online advertising revenue format. Online publishers use different formats of unit price auctions to sell advertising slots. In the Trading Agent Competition Ad Auctions (TAC/AA) game, intelligent software agents represent a publisher which conduct keyword auctions and advertisers which participate in those auctions. The publisher is designed by game creators while advertisers are designed by game entrants. Advertisers bid for the placement of their ads on the publisher’s web page and the main challenge placed before them is how to determine the right amount they should bid for a certain keyword. In this paper, we present the CrocodileAgent, our entry in the 2010 TAC AA Tournament. The agent’s architecture is presented and a series of controlled experiments are discussed.

Agent-Mediated Electronic Commerce. Designing Trading Strategies and Mechanisms for Electronic Markets, 2014

This paper provides insights into performance of competing agents in Power Trading Agent Competit... more This paper provides insights into performance of competing agents in Power Trading Agent Competition finals held in May 2014. Firstly, the paper gives the description of the Power TAC post-game data set and presents our analysis process. Furthermore, paper discusses the analysis output: indicators about brokers performance in energy retail market, energy wholesale market as well as the balancing process. Results of the analysis identified diverse approaches in the design of competing agents strategies.

Cases on Web 2.0 in Developing Countries: Studies on Implementation, Application, and Use, 2013

In the Web 1.0 era users were passive consumers of a read-only web. However, the emergence of the... more In the Web 1.0 era users were passive consumers of a read-only web. However, the emergence of the Web 2.0 redefined a way people use information and communication services – users evolved into prosumers which actively participate and collaborate in the ecosystem of a read-write web. Consequently, marketing is one among many areas affected by an advent of the Web 2.0 paradigm. Namely, Web 2.0 enabled global proliferation of a social networking, which again is a foundation for Social Media Marketing. Social Media Marketing represents a novel Internet marketing paradigm based on spreading brand-related messages directly from one user to another. This is also the reason why Social Media Marketing is often referred as the viral marketing. This chapter will describe: (i) how social networking became the most popular Web 2.0 service, and (ii) how social networking revolutionized Internet marketing. Both issues will be elaborated on two levels – the global and the Croatian level. Namely, the chapter will first present the evolution of social networking phenomenon which has fundamentally changed the way how Internet users utilize web services. During the first decade of 21st century millions of people joined online communities and started using online social platforms, what led towards 1.5 billion members of social networks globally in 2012. Furthermore, the chapter will describe how Internet marketing provided marketers with innovative marketing channels which offer marketing campaign personalization, low-cost global access to consumers and simple, cheap and real-time marketing campaign tracking. Specifically, chapter will focus on Social Media Marketing, the latest step in Internet marketing evolution. Three most popular Social Media Marketing platforms (i.e., Facebook, Twitter and Foursquare) will be described, as well as examples of successful marketing case studies in Croatia presented.

Agreement Technologies, 2013

In this chapter we discuss how semantic technologies in general and specific Semantic Web standar... more In this chapter we discuss how semantic technologies in general and specific Semantic Web standards in particular can contribute to the goal of achieving interoperability between independent, loosely coupled, heterogeneous, autonomous software components (i.e. agents) and for the realization of open interaction systems. In particular we will discuss how those technologies have been used for the definition of the semantics of agent communication languages, for the definition of norms and policies used to regulate interactions in open frameworks, and for defining efficient mechanisms for matching demands (i.e., content they need) to supplies (i.e., available content) in telecommunication networks. In particular regarding this last type of application we describe a techno-economic approach for solving the matching problem, by means of a multi-agent system representing an electronic marketplace. Its functionality is realized by applying a semantic-aware content discovery model with two-level filtering in order to finally recommend a ranked set of eligible content to the users in response to their requests. The filtering processes not only consider the semantic information associated with the available content, but also ratings regarding the actual performance of businesses that act as content providers as well as the prices paid by businesses for advertising their content.

Computational Social Networks, 2012

At the end of 2010, we are at the effective end of the second phase of research in the field of S... more At the end of 2010, we are at the effective end of the second phase of research in the field of Social Networks (SNs) and aspects such as Human-to-Human (H2H) interactions have pretty much had their day due to advances in Machine-to-Machine (M2M) interactions. This chapter will provide a useful insight into the differences between those two types of SNs: the human SNs (hSNs) based on H2H interactions and the machine SNs (mSNs) based on M2M interactions. During the last two decades rapid improvements in computing and communication technologies have enabled a proliferation of hSNs and we believe they will induce the formation of mSNs in the next decades. To this end, we will show how to carry out successful SN analyses (e.g. clustering and data diffusion) by connecting ethological approaches to social behaviour in animals (e.g. the study of firefly synchronization) and M2M interactions.

Lecture Notes in Computer Science, 2006

Applications and Systems, 2008

Lecture Notes in Computer Science, 2008

2014 22nd International Conference on Software, Telecommunications and Computer Networks (SoftCOM), 2014

Proceeding of 12th International Conference on Telecommunications (ConTEL 2013), 2013

Service-Oriented Computing: Agents, Semantics, and Engineering

Agent and Multi-Agent Systems: Technologies and Applications

Knowledge-Based and Intelligent Information and Engineering Systems

Transactions on Computational Collective Intelligence II

Agent and Multi-Agent Systems: Technologies and Applications

Agent and Multi-Agent Systems. Technologies and Applications

Agent-Mediated Electronic Commerce. Designing Trading Strategies and Mechanisms for Electronic Markets

Agent-Mediated Electronic Commerce. Designing Trading Strategies and Mechanisms for Electronic Markets, 2014

Cases on Web 2.0 in Developing Countries: Studies on Implementation, Application, and Use, 2013

Agreement Technologies, 2013

Computational Social Networks, 2012

nnovations in Multi-Agent Systems and Applications - 1, 2010

The chapter deals with group-oriented service provisioning in next-generation network (NGN). It c... more The chapter deals with group-oriented service provisioning in next-generation network (NGN). It consists of three parts: the first bringing forth user profile creation and semantic comparison; the second explaining user profile clustering and semantic classification; and the third describing social network creation and analysis. The multi-agent system A-STORM (Agent-based Service and Telecom Operations Management) is presented and elaborated as part of the proof-of-concept prototype which demonstrates provisioning of group-oriented services within NGN. As a group-oriented service, the RESPIRIS (Recommendation-based Superdistribution of Digital Goods within Implicit Social Networks) service is implemented and provisioned by using prototype’s agents. The proposed provisioning scenario is set forth, as well as provisioning process analysis presented.

Encyclopedia of E-Business Development and Management in the Digital Economy, 2010

In a global multi-service and multi-provider market, Internet Service Providers (ISPs) will incre... more In a global multi-service and multi-provider market, Internet Service Providers (ISPs) will increasingly need to base their operation on new consumer-centric business models. In this article, we present an agent-based framework for the Business-to-Consumer (B2C) electronic market, comprising User Agents, Broker Agents and Provider Agents, which enable Internet users to select an ISP in an automated manner.

Knowledge Processing and Decision Making in Agent-Based Systems, 2009

Today, there is a wide variety of telecom services available provided by a number of competing st... more Today, there is a wide variety of telecom services available provided by a number of competing stakeholders in the telecom environment. Consequently, consumers in such an environment require efficient mechanisms to match their demands (requested services) to supplies (available services). Businesses, on the other hand, aim to achieve efficient allocation of their resources. This chapter introduces a combination of Artificial Intelligence mechanisms and Computational Economics concepts as a means of solving the above mentioned problems. These mechanisms and concepts are implemented in agent-based electronic markets. Electronic markets function as digital intermediaries that create value by bringing consumers and providers together to create transactional immediacy and supply liquidity, by supporting the exchange of demand and supply information, and reducing transaction costs. The efficiency of the created multi-agent system is realized by applying novel discovery and/or negotiation models.

Agent Technologies and Web Engineering: Applications and Systems, 2009

This paper presents an application of multi-agent system in ubiquitous computing scenarios charac... more This paper presents an application of multi-agent system in ubiquitous computing scenarios characteristic of next-generation networks. Next-generation networks will create environments populated with a vast number of consumers, which will possess diverse types of context-aware devices. In such environments the consumer should be able to access all the available services anytime, from any place, and by using any of its communication-enabled devices. Consequently, next-generation networks will require efficient mechanisms which can match consumers’ demands (requested services) to network-operators’ supplies (available services). The authors propose an agent approach for enabling autonomous coordination between all the entities across the telecom value chain, thus enabling automated context-aware service provisioning for the consumers. Furthermore, the authors hope that the proposed service discovery model will not only be interesting from a scientific point of view, but also amenable to real-world applications.

Global competition is putting a premium on the ability to manage risk through flexible and agile ... more Global competition is putting a premium on the ability to manage risk through flexible and agile web-enabled procurement practices. This article discusses the design of the 2007 “supply chain management – procurement challenge” (SCM-PC), a competition designed by the first three authors to evaluate the performance of mixed procurement strategies that balance risk through combinations of long-term, quantity-flexible contracts and one-off contracts. Specifically, the SCM-PC challenge revolves around a PC assembly scenario, where web-enabled trading agents developed by different teams compete for components required to assemble different types of PCs. Collectively the authors represent the top three entries in the 2007 procurement challenge. They present the strategies their teams developed for the competition, compare their performances, and discuss lessons learned from the competition.

This paper proposes a distributed model of service provisioning process for mobile network users ... more This paper proposes a distributed model of service provisioning process for mobile network users who share a common interest in a service content offered in the network. The model is based on an idea that such users could individually acquire disjunctive parts of service content from a remote server (via a wide area mobile network), and then subsequently exchange them among themselves in an ad hoc local network in a peer-to-peer fashion, thus allowing each user to reassemble the entire content for her/his own use. The benefits of this approach include lowering the load on the “expensive” link to the telco’s network and saving the energy for wide-area communication on users’ mobile devices. The key questions to solve include recognizing the “common interest” of users and achieving their collaboration as described above. As an example, we show a service in which mobile users form an implicit social network and collaborate while downloading a selected multimedia content from the server under the control of the telco. A proof-of-concept implementation, named Collaborative Downloading (CollDown for short), is evaluated by using real mobile phones in a real network.

International Journal of Intelligent Information and Database Systems

Recent technical advancements in computing devices and communication networks, combined with chan... more Recent technical advancements in computing devices and communication networks, combined with changes in the way people use information and communication technology (ICT) systems, have transformed the ICT industry. In this article, we present the collaborative urban computing (CUC) paradigm, which supports serendipitous cooperation between a set of users physically located in an urban environment and all sharing a common goal. Advantages and disadvantages of the CUC paradigm are elaborated on a proof-of-concept CUC service, which we call collaborative downloading.

The reduction of cost and complexity is a key driver in the evolution of mobile networks. This re... more The reduction of cost and complexity is a key driver in the evolution of mobile networks. This reduction not only applies to the pre-operational state (e.g. the deployment phase of a new network), but to the operational state as well. During the operational state, self-optimization processes can be performed to reduce the operating expenses (OPEX) of telecommunications operators. In this paper, we propose an agent-based mechanism for auto-tuning mobile networks with the aim of achieving energy savings in access networks. Firefly-based synchronization is used for the coordination of mutually dependent software agents located at the operator’s base stations. Once synchronized, agents can act together to obtain a global goal – i.e. the reduction of the telecommunications operator’s costs without reducing the quality of the provided services for mobile users. These agents build a self-organized overlay network where neither centralized nor decentralized control is needed and, therefore, is more robust.

Green communication is a new focus within the telecommunications industry, leading to various inn... more Green communication is a new focus within the telecommunications industry, leading to various innovative ideas on how to optimize communication in order to achieve energy savings. While the majority of those ideas target the transport layer of communication systems, this paper takes a different approach and proposes an innovation for the application layer by introducing a novel concept in the mobile telecom service provisioning process: the swarm-oriented services. The presented proof-of-concept swarm-oriented mobile telecom service is called the Collaborative Downloading and its primary goal is to lower the mobile users’ overall energy consumption while they are downloading data. In order to enable this service, we designed the self-organizing market-based algorithm (SOMA), which combines swarm intelligence (i.e. self-organization) and market-based (i.e. auctions) mechanisms, while the proof-of-concept implementation is based on multi-agent technology. Analytical results show that the proposed Collaborative Downloading service saved up to 76% of energy in mobile device batteries when compared with the current mobile data download practice (in a scenario with 6 mobile users whose mobile devices support GPRS and Bluetooth networking technologies).

With the constantly increasing competition on the information service market, service providers s... more With the constantly increasing competition on the information service market, service providers should enhance their business processes by introducing new mechanisms. These novel mechanisms must include almost real-time detection of business opportunities (as well as possible failures), necessary resource prediction, and finally profit forecasting. Presented challenges can be tackled by using growth models for service acceptance prediction. However, common growth models have certain shortcomings when it comes to forecasting consumer interest in new services. Two main shortcomings are: i) limited precision; and ii) a short, but yet existing, time delay. Possible solution that minimizes the specified shortcomings is semantic reasoning, which can be used for detecting similarities between services already on the market and ones that are just to be introduced. Consequently, it becomes possible both to increase forecasting precision and eliminate time delay caused by the need to collect a certain amount of data about the new service before any prediction can be made. Our approach, the semantic-aware prediction model, can thus replace the common subjective service similarity approximation approach. Elaboration and verification of the semantic-aware prediction model are conducted on a case of forecasting YouTube clip popularity.

The AAAI-13 Workshop Program, a part of the 27th AAAI Conference on Artificial Intelligence, was ... more The AAAI-13 Workshop Program, a part of the 27th AAAI Conference on Artificial Intelligence, was held Sunday and Monday, July 14‚Äì15, 2013 at the Hyatt Regency Bellevue Hotel in Bellevue, Washington, USA. The program included 12 workshops covering a wide range of topics in artificial intelligence, including Activity Context-Aware System Architectures (WS-13-05); Artificial Intelligence and Robotics Methods in Computational Biology (WS-13-06); Combining Constraint Solving with Mining and Learning (WS-13-07); Computer Poker and Imperfect Information (WS-13-08); Expanding the Boundaries of Health Informatics Using Artificial Intelligence (WS-13-09); Intelligent Robotic Systems (WS-13-10); Intelligent Techniques for Web Personalization and Recommendation (WS-13-11); Learning Rich Representations from Low-Level Sensors (WS-13-12); Plan, Activity, and Intent Recognition (WS-13-13); Space, Time, and Ambient Intelligence (WS-13-14); Trading Agent Design and Analysis (WS-13-15); and Statistical Relational Artificial Intelligence (WS-13-16).