Ohjelmistotestauksen käytänteet Suomessa

Ohjelmistotestauksen merkitys on kasvanut sen mukaan mitä enemmän ohjelmisto-tuotteet vaikuttavat jokapäiväisesseen elämämme. Tämän vuoksi yritysten investointien ja laadunvarmentamisen yhteys on ilmeinen. Organisaatiot panostavat yhä enemmän ei–funktionaaliseen testaukseen, kuten turvallisuuden, suorituskyvyn ja käytettävyyden testaamiseen. Tämän työn tarkoituksena on tutkia ohjelmistotestauksen nykytilannetta Suomessa. Syy tähän on uudistaa ja parantaa ohjelmistotestauksen kurssitarjontaa Turun yliopistossa vastaamaan parhaalla mahdollisella tavalla yritysten tarvetta. Opinnäyte on toteutettu replikaatio-tutkimuksena. Pääosa kyselystä sisältää kysymyksiä ohjelmistotestauksen menetelmistä ja työkaluista testausprosessin toimintojen aikana. Lisäksi on yleisiä kysymyksiä yrityksistä ja niiden ohjelmistotestausympäristöistä. Kyselyssä otetaan myös kantaa yritysten käyttämiin monenlaisiin testaus-tasoihin, -tyyppeihin ja testauksessa kohdattuihin haasteisiin. Tämä opinnäyte perustuu testausprosessistandardeihin. Ohjelmistotestausstandardit ovat keskeisessä asemassa tässä työssä, vaikka ne ovat olleet viime aikoina vahvan kritiikin kohteena. Epäilys standardien välttämättömyyteen on syntynyt muutoksista ohjelmistokehityksessä. Tämä työ esittelee tulokset ohjelmistotestauksen käytännöistä. Tuloksia on verrattu aiheeseen liittyvän aiemman kyselyn (Lee, Kang, & Lee, 2011) tuloksiin. Ajanpuutteen havaitaan olevan suuri haaste ohjelmistotestauksessa. Ketterä ohjelmistokehitys on saavuttanut suosiota kaikissa vastaajien yrityksissä. Testauksen menetelmät ja työkalut testauksen arviointiin, suunnitteluun ja raportointiin ovat hyvin vähäisessä käytössä. Toisaalta testauksen menetelmien ja työkalujen käyttö automaattiseen testauksen toteuttamiseen ja virheiden hallintaan on lisääntynyt. Järjestelmä-, hyväksyntä-, yksikkö- ja integraatiotestaus ovat käytössä kaikkien vastaajien edustamissa yrityksissä. Kaikkien vastaajien mielestä regressio- sekä tutkiva- ja ei-funktionaalinen testaus ovat tärkeitä tekniikoita.

Proximity Based Authentication in IoT

IoT consists of essentially thousands of tiny sensor nodes interconnected to the internet, each one of which executes the programmed functions under memory and power limita- tions. The sensor nodes are distributed mainly for gathering data in various situations. IoT envisions the future technologies such as e-health, smart city, auto-mobiles automa- tion, construction sites automation, and smart home. Secure communication of data under memory and energy constraints is major challenge in IoT. Authentication is the first and important phase of secure communication. This study presents a protocol to authenticate resource constraint devices in physical proximity by solely using the shared wireless communication interfaces. This model of authentication only relies on the abundance of ambient radio signals to authenticate in less than a second. To evaluate the designed protocol, SkyMotes are emulated in a network environment simulated by Contiki/COOJA. Results presented during this study proves that this approach is immune against passive and active attacks. An adversary located as near as two meters can be identified in less than a second with minimal expense of energy. Since, only radio device is used as required hardware for the authentication, this technique is scalable and interoperable to heterogeneous nature of IoT.

Improve the production capacity: A case study of Eurofins Viljavuuspalvelu Oy

In any manufacturing system, there are many factors that are affecting and limiting the capacity of the entire system. This thesis addressed a study on how to improve the production capacity in a Finnish company (Viljavuuspalvelu Oy) through different methods like bottleneck analysis, Overall Equipment Effectiveness (OEE), and Just in Time production. Four analyzing methods have been studied in order to detect the bottleneck machine in Viljavuuspalvelu Oy. The results shows that the bottleneck machine in the industrial area that constraint the production is the grinding machine while the bottleneck machine in the laboratory section is the photometry machine. In addition, the Overall Equipment Effectiveness (OEE) of the entire system of the studied case was calculated and it has been found that the OEE of the Viljavuuspalvelu Oy is 35.75%. Moreover, two methods on how to increase the OEE were studied and it was shown that either the total output of the company should be 1254 samples/shift in order to have an OEE around 85% which is considered as a world class or the Ideal run rate should be 1.45 pieces/minute. In addition, some realistic methods are applied based on the finding in this thesis to increase the OEE factor in the company and in one realistic method the % OEE has increase to 62.59%. Finally, an explanation on how to implement the Just in Time production in Viljavuuspalvelu Oy has been studied.

Real-time simulation of multibody systems with applications for working mobile vehicles

This dissertation describes an approach for developing a real-time simulation for working mobile vehicles based on multibody modeling. The use of multibody modeling allows comprehensive description of the constrained motion of the mechanical systems involved and permits real-time solving of the equations of motion. By carefully selecting the multibody formulation method to be used, it is possible to increase the accuracy of the multibody model while at the same time solving equations of motion in real-time. In this study, a multibody procedure based on semi-recursive and augmented Lagrangian methods for real-time dynamic simulation application is studied in detail. In the semirecursive approach, a velocity transformation matrix is introduced to describe the dependent coordinates into relative (joint) coordinates, which reduces the size of the generalized coordinates. The augmented Lagrangian method is based on usage of global coordinates and, in that method, constraints are accounted using an iterative process. A multibody system can be modelled as either rigid or flexible bodies. When using flexible bodies, the system can be described using a floating frame of reference formulation. In this method, the deformation mode needed can be obtained from the finite element model. As the finite element model typically involves large number of degrees of freedom, reduced number of deformation modes can be obtained by employing model order reduction method such as Guyan reduction, Craig-Bampton method and Krylov subspace as shown in this study The constrained motion of the working mobile vehicles is actuated by the force from the hydraulic actuator. In this study, the hydraulic system is modeled using lumped fluid theory, in which the hydraulic circuit is divided into volumes. In this approach, the pressure wave propagation in the hoses and pipes is neglected. The contact modeling is divided into two stages: contact detection and contact response. Contact detection determines when and where the contact occurs, and contact response provides the force acting at the collision point. The friction between tire and ground is modelled using the LuGre friction model, which describes the frictional force between two surfaces. Typically, the equations of motion are solved in the full matrices format, where the sparsity of the matrices is not considered. Increasing the number of bodies and constraint equations leads to the system matrices becoming large and sparse in structure. To increase the computational efficiency, a technique for solution of sparse matrices is proposed in this dissertation and its implementation demonstrated. To assess the computing efficiency, augmented Lagrangian and semi-recursive methods are implemented employing a sparse matrix technique. From the numerical example, the results show that the proposed approach is applicable and produced appropriate results within the real-time period.