Studies of Eu- and Yb-induced Reconstructions on the Si(100) Surface

This thesis presents experimental studies of rare earth (RE) metal induced structures on Si(100) surfaces. Two divalent RE metal adsorbates, Eu and Yb, are investigated on nominally flat Si(100) and on vicinal, stepped Si(100) substrates. Several experimental methods have been applied, including scanning tunneling microscopy/spectroscopy (STM/STS), low energy electron diffraction (LEED), synchrotron radiation photoelectron spectroscopy (SR-PES), Auger electron spectroscopy (AES), thermal desorption spectroscopy (TDS), and work function change measurements (Δφ). Two stages can be distinguished in the initial growth of the RE/Si interface: the formation of a two-dimensional (2D) adsorbed layer at submonolayer coverage and the growth of a three-dimensional (3D) silicide phase at higher coverage. The 2D phase is studied for both adsorbates in order to discover whether they produce common reconstructions or reconstructions common to the other RE metals. For studies of the 3D phase Yb is chosen due to its ability to crystallize in a hexagonal AlB2 type lattice, which is the structure of RE silicide nanowires, therefore allowing for the possibility of the growth of one-dimensional (1D) wires. It is found that despite their similar electronic configuration, Eu and Yb do not form similar 2D reconstructions on Si(100). Instead, a wealth of 2D structures is observed and atomic models are proposed for the 2×3-type reconstructions. In addition, adsorbate induced modifications on surface morphology and orientational symmetry are observed. The formation of the Yb silicide phase follows the Stranski-Krastanov growth mode. Nanowires with the hexagonal lattice are observed on the flat Si(100) substrate, and moreover, an unexpectedly large variety of growth directions are revealed. On the vicinal substrate the growth of the silicide phase as 3D islands and wires depends drastically on the growth conditions. The conditions under which wires with high aspect ratio and single orientation parallel to the step edges can be formed are demonstrated.

Verkkopohjainen palautusjärjestelmä harjoitustöille

Tiedostojen palautus erilaisissa kursseissa yleistyy. Harjoituksia ja harjoitustöitä palautetaan erilaisissa tiedostomuodoissa, yleensä sähköpostin välityksellä. Oppilaat saattavat palauttaa tiedostoja väärin nimettynä tai tiedostotyyppi on väärä, joka hankaloittaa tarkastusta. Oppilas määrän ollessa suuri, tulee palautuksia myös paljon, joka täyttää tarkastajan sähköpostin. Tämän kandidaatintyön tarkoitus on selventää mitkä ohjelmointikielet kävisivät verkkopohjaisen palautusjärjestelmän toteutukseen. Verkkopohjainen palautusjärjestelmä toteutetaan kirjallisuudesta löytyvän materiaalin perusteella.

Evaluating End-User Training Effectiveness in ERP System Implementation

Today’s business world demands more and more internal and external integration and transparency among companies at all fields. Integrated ERP (enterprise resource planning) systems offer a possibility to improve business practices and procedures by providing a unified view on the business including all functions and departments. Due to the obvious benefits, the popularity of integrated ERP systems keeps growing. The implementation of ERP systems has however proven risky. The implementation projects tend to be long, extensive, and costly – and often they end up in a failure. Due to the significant task and role changes ERP implementation brings to almost everybody in the company, training has been identified as one of the most critical success factors of an ERP implementation. To ensure that the training is conducted in the most effective and successful manner, the training outcomes should be evaluated. So far, training evaluation has however gained only limited attention at most companies investing in different training programs. Uponor corporation has initiated a large ERP implementation and process harmonization program in 2004. Thousands of end-users have been trained during this project so far, and the work still continues until the project is completed in 2010. In this thesis, the evaluation of end-user training in Uponor’s ERP program is brought further from the current state of performing the basic participant satisfaction survey in the end of each class. The results show that in order to reach reliable training effectiveness evaluation results, not only the reaction towards training but also transfer of skills and attitudes and the final results of the training program should be evaluated.

Kertomuksia kohtaamisista ja kohtaamisen vaikeuksista

Kirjallisuusarvostelu

Kirkko, virka ja sukupuolisuus

Kirjallisuusarvostelu

Näkökulmia muutoksen johtamiseen

Kirjallisuusarvostelu

Käyttäjät asuintiloissa

Kirjallisuusarvostelu

Suomenlahden ulkosaaret muistoissa

Kirjallisuusarvostelu