Alexandru Archip | "Gheorghe Asachi" Tehnical University of Iasi (original) (raw)

Papers by Alexandru Archip

With the growth of the Internet, recommendations have become a fact of life and there is a big co... more With the growth of the Internet, recommendations have become a fact of life and there is a big competition between companies to get as much market share as possible. This is achievable not only through fast to market solutions but also by constantly providing high quality services. Considering the speed of current technological advancements, it is impossible to conceive a world without some form of prediction. Traditionally, recommendations have been computed using the collaborative filtering method, but the growth of available information has pushed research into other directions such as content based, demographic based, utility-based, knowledge-based and hybrids. This paper provides an introduction to collaborative filtering and content based methods, describing the underlying concepts, and discusses possible improvements using overclassification. Individual results are presented and then compared with the overclassification approach.

2023 27th International Conference on System Theory, Control and Computing (ICSTCC)

Proceedings of the 2nd International Workshop on Architectures, Concepts and Technologies for Service Oriented Computing, 2008

Exploiting the power of the grid very often involves transforming existing or new applications in... more Exploiting the power of the grid very often involves transforming existing or new applications into grid services. In this paper we present a generic framework based on a service oriented architecture developed in order to simplify the task of deploying applications as grid services. Our work consists of a configurable grid service that provides application developers with a high level programming model, hiding the complexity of dealing with web services and grid technologies. The architectural design of the framework allows custom functionality to be plugged into an adaptive grid service in a simple manner, thus attracting more non-expert users to the grid. A prototype implementation of the framework has been built and a case study has been developed to illustrate the concept.

Bulletin of the Polytechnic Institute of Iași. Electrical Engineering, Power Engineering, Electronics Section

Designing a security solution should rely on having a good knowledge of the protected assets and ... more Designing a security solution should rely on having a good knowledge of the protected assets and better develop active responses rather than focus on reactive ones. We argue and prove that malicious activities such as vulnerabilities exploitation and (D)DoS on Web applications can be detected during their respective initial phases. While they may seem distinct, both attack scenarios are observable through abnormal access patterns. Following on this remark, we first analyze Web access logs using association rule mining techniques and identify these malicious traces. This new description of the historical data is then correlated with Web site structure information and mapped over trie data structures. The resulted trie is then used for every new incoming request and we thus identify whether the access pattern is legitimate or not. The results we obtained using this proactive approach show that the potential attacker is denied the required information for orchestrating successful assau...

2009 11th International Symposium on Symbolic and Numeric Algorithms for Scientific Computing, 2009

Simulation of quantum computers using classical computers is a computationally hard problem, requ... more Simulation of quantum computers using classical computers is a computationally hard problem, requiring a huge amount of operations and storage. Grid systems are a good choice for simulating quantum algorithms, since they provide access to high-performance computer clusters. In this paper we present the design of a message passing parallel version of the quantum computer simulator, QCL, deployed as a

Studies in Computational Intelligence, 2014

Increasing demands of flexible automating manufacturing processes made robots with vision systems... more Increasing demands of flexible automating manufacturing processes made robots with vision systems to be frequently used due to their ability to adapt to new environments and various conditions. This paper presents a visual servoing system for real time picking and placing of dynamic objects. The system is integrated into a manufacturing cell and its structure consists in a CCD camera with SIFT detector, an image based predictive controller and a robot manipulator. Using a Service Oriented Architecture (SOA), the visual servoing system is implemented and different experimental testing of the vision-guided robot predictive control architecture is conducted.

Roy Thomas Fielding defined the term REST as an architectural style for distributed hypermedia ba... more Roy Thomas Fielding defined the term REST as an architectural style for distributed hypermedia based systems in the year 2000. Since this initial definition, the term itself became a buzzword used in almost any web-related development. From simple, basic web applications, to highly complex web service/microservice-based solutions, almost everyone and everything talks REST and RESTful. Moreover, the Web context implies that these developments are usually realised over HTTP. In this paper, we first analyse the impact of this architectural style on distributed application development. A careless application of this model and its underlying HTTP standards could severely impact on the overall quality of any RESTful based solution. Following, we submit our own model for user data and session handling tasks to illustrate the correct approach to RESTful web service design techniques. This model offers all the advantages of the aforementioned architectural style while providing the required ...

Association Rule Mining (ARM) represents an important tool for Data Mining techniques. A key step... more Association Rule Mining (ARM) represents an important tool for Data Mining techniques. A key step in ARM is to determine the frequent itemsets present within the analyzed data. Recent algorithms addressing this problem focus on identifying frequent itemsets without candidate generation steps. This paper details a new algorithm - Fast Itemset Miner (FIM for short) - that still relies on candidate generation stages, but has a different approach from the standard Apriori algorithm. This approach focuses on increasing size of the interval that candidates belong to, rather than increasing the size of the candidates by one with each corresponding iteration. By comparing the Apriori and FIM candidate generation stages, we show that this second approach uses a faster and more efficient method of determining candidate itemsets. Moreover, such an approach also favors a better support counting method, which greatly impacts on the overall time response of the FIM algorithm.

A parallel algorithm for finding the frequent itemsets in a set of transactions is presented. The... more A parallel algorithm for finding the frequent itemsets in a set of transactions is presented. The frequent individual items are identified by their index. We assume that processors number (m) is less than the frequent items number (n). At the first stage, every processor Pi, i isin; {1, ...,m - 1} sequentially computes the frequent itemsets from the interval Ii = [(i - 1) cdot; p + 1, i cdot; p], where p = lfloor;n/mrfloor;. The processor Pm computes frequent itemsets from the interval Im = [(m - 1) cdot; p + 1, n]. In the second stage, the parallel algorithm is applied. The processor Pi computes, step by step, the sets FIi,Ij of the frequent itemsets with individual items from the intervals Ii,j = Ii∪Ii+1∪...∪Ij, j = i+1,...,m. In order to compute the set FIi,Ij, the processor Pi uses FIi,Ij-1 obtained in the previous step and FIi+1,Ij received from the processor Pi+1. The main advantage of our parallel algorithm is that it uses a communication pattern known before algorithm start,...

Electronics

Digital security plays an ever-increasing, crucial role in today’s information-based society. The... more Digital security plays an ever-increasing, crucial role in today’s information-based society. The variety of threats and attack patterns has dramatically increased with the advent of digital transformation in our lives. Researchers in both public and private sectors have tried to identify new means to counteract these threats, seeking out-of-the-box ideas and novel approaches. Amongst these, data analytics and artificial intelligence/machine learning tools seem to gain new ground in digital defence. However, such instruments are used mainly offline with the purpose of auditing existing IDS/IDPS solutions. We submit a novel concept for integrating machine learning and analytical tools into a live intrusion detection and prevention solution. This approach is named the Experimental Cyber Attack Detection Framework (ECAD). The purpose of this framework is to facilitate research of on-the-fly security applications. By integrating offline results in real-time traffic analysis, we could de...

2016 17th International Carpathian Control Conference (ICCC), 2016