Helsinki University of Technology

About: Helsinki University of Technology is a based out in . It is known for research contribution in the topics: Artificial neural network & Finite element method. The organization has 8962 authors who have published 20136 publications receiving 723787 citations. The organization is also known as: TKK & Teknillinen korkeakoulu.

Requirements prioritization challenges in practice

Abstract: Requirements prioritization is recognized as an important activity in product development. In this paper, we describe the current state of requirements prioritization practices in two case companies and present the practical challenges involved. Our study showed that requirements prioritization is an ambiguous concept and current practices in the companies are informal. Requirements prioritization requires complex context-specific decision-making and must be performed iteratively in many phases during development work. Practitioners are seeking more systematic ways to prioritize requirements but they find it difficult to pay attention to all the relevant factors that have an effect on priorities and explicitly to draw different stakeholder views together. In addition, practitioners need more information about real customer preferences.

Synthesis and Characterization of a Biodegradable Thermoplastic Poly(ester-urethane) Elastomer.

Abstract: Thermoplastic poly(ester−urethanes) were polymerized in a two-step process: a condensation copolymerization of lactic acid (LA) and e-caprolactone (CL), using stannous octoate as catalyst, followed by an increase in the molecular weight through urethane linking. The use of 1,4-butanediol results in oligomer molecules with hydroxyl functionality at both ends. The effect of comonomer ratio on the thermal and mechanical properties of the poly(ester−urethane) was investigated. SEC, FTIR, and 13C NMR were used to confirm the formation and structure of the polymer; a random sequence distribution of the comonomer units was concluded along the polymeric chains. All poly(ester−urethanes) were amorphous, with Tg varying from 53 to −45 °C. Poly(ester−urethanes) with a small amount of CL units were rigid, having a tensile modulus of 1700−2100 MPa, maximum stress of 36−47 MPa, and maximum strain of 4−7%. CL-rich poly(ester−urethanes) were highly elastomeric with maximum stress of 9 MPa and with maximum strain over 10...

Interference-avoiding MIMO schemes for device-to-device radio underlaying cellular networks

Abstract: An underlaying direct Device-to-Device (D2D) communication mode in future cellular networks, such as IMT-Advanced, is expected to provide spectrally efficient and low latency support of e.g. rich multi-media local services. Enabling D2D links in a cellular network presents a challenge in transceiver design due to the potentially severe interference between the cellular network and D2D radios. In this paper we propose MIMO transmission schemes for cellular downlink that avoid generating interference to a D2D receiver operating on the same time-frequency resource. System simulations demonstrate that substantial gains in D2D SINR of up to 15 dB and around 10% total cell capacity gains can be obtained by using the proposed scheme.

Joking, storytelling, artsharing, expressing affection: a field trial of how children and their social network communicate with digital images in leisure time

Abstract: Increasing use of mobile phones in leisure and communication with digital images are important and current issues in the field of telecommunications. However, little is known about how images would be used in leisure related communication. According to our experience field trials are the best way of studying it. In this paper, we describe a field-trial case study of leisure related communication with digital images. Moreover, we discuss the advantages of conducting field trials as part of product concept design process.