The Electronic Journal of Information Technology in Construction (ITcon): An Open Access Journal Using an Un-paid, Volunteer-Based Organization

Introduction This case study is based on the experiences with the Electronic Journal of Information Technology in Construction (ITcon), founded in 1995. Development This journal is an example of a particular category of open access journals, which use neither author charges nor subscriptions to finance their operations, but rely largely on unpaid voluntary work in the spirit of the open source movement. The journal has, after some initial struggle, survived its first decade and is now established as one of half-a-dozen peer reviewed journals in its field. Operations The journal publishes articles as they become ready, but creates virtual issues through alerting messages to “subscribers”. It has also started to publish special issues, since this helps in attracting submissions, and also helps in sharing the work-load of review management. From the start the journal adopted a rather traditional layout of the articles. After the first few years the HTML version was dropped and papers are only published in PDF format. Performance The journal has recently been benchmarked against the competing journals in its field. Its acceptance rate of 53% is slightly higher and its average turnaround time of seven months almost a year faster compared to those journals in the sample for which data could be obtained. The server log files for the past three years have also been studied. Conclusions Our overall experience demonstrates that it is possible to publish this type of OA journal, with a yearly publishing volume equal to a quarterly journal and involving the processing of some fifty submissions a year, using a networked volunteer-based organization.

End-User Attitudes Towards EDM Use in Construction Project Work: Case Study

This article reports on a cross-sectional case study of a large construction project in which Electronic document management (EDM) was used. Attitudes towards EDM from the perspective of individual end users were investigated. Responses from a survey were combined with data from system usage log files to obtain an overview of attitudes prevalent in different user segments of the total population of 334 users. The survey was followed by semi-structured interviews with representative users. A strong majority of users from all segments of the project group considered EDM as a valuable aid in their work processes, despite certain functional limitations of the system used and the complexity of the information mass. Based on the study a model describing the key factors affecting end user EDM adoption is proposed. The model draws on insight from earlier studies of EDM enabled projects and theoretical frameworks on technology acceptance and success of information systems, as well as the insights gained from the case study.

Use of Document Management Systems - a Case Study of the Finnish Construction Industry

Triggered by the very quick proliferation of Internet connectivity, electronic document management (EDM) systems are now rapidly being adopted for managing the documentation that is produced and exchanged in construction projects. Nevertheless there are still substantial barriers to the efficient use of such systems, mainly of a psychological nature and related to insufficient training. This paper presents the results of empirical studies carried out during 2002 concerning the current usage of EDM systems in the Finnish construction industry. The studies employed three different methods in order to provide a multifaceted view of the problem area, both on the industry and individual project level. In order to provide an accurate measurement of overall usage volume in the industry as a whole telephone interviews with key personnel from 100 randomly chosen construction projects were conducted. The interviews showed that while around 1/3 of big projects already have adopted the use of EDM, very few small projects have adopted this technology. The barriers to introduction were investigated through interviews with representatives for half a dozen of providers of systems and ASP-services. These interviews shed a lot of light on the dynamics of the market for this type of services and illustrated the diversity of business strategies adopted by vendors. In the final study log files from a project which had used an EDM system were analysed in order to determine usage patterns. The results illustrated that use is yet incomplete in coverage and that only a part of the individuals involved in the project used the system efficiently, either as information producers or consumers. The study also provided feedback on the usefulness of the log files.

Bank Run Risk and Optimal Reserves

We characterize the optimal reserves, and the generated probability of a bank run, as a function of the penalty imposed by the central bank, the probability of depositors’ liquidity needs, and the return on outside investment opportunities.

Examining and Modeling the Dynamics of the Volatility Surface

The objective of this paper is to investigate and model the characteristics of the prevailing volatility smiles and surfaces on the DAX- and ESX-index options markets. Continuing on the trend of Implied Volatility Functions, the Standardized Log-Moneyness model is introduced and fitted to historical data. The model replaces the constant volatility parameter of the Black & Scholes pricing model with a matrix of volatilities with respect to moneyness and maturity and is tested out-of-sample. Considering the dynamics, the results show support for the hypotheses put forward in this study, implying that the smile increases in magnitude when maturity and ATM volatility decreases and that there is a negative/positive correlation between a change in the underlying asset/time to maturity and implied ATM volatility. Further, the Standardized Log-Moneyness model indicates an improvement to pricing accuracy compared to previous Implied Volatility Function models, however indicating that the parameters of the models are to be re-estimated continuously for the models to fully capture the changing dynamics of the volatility smiles.

Epidemiology of candidemia in Finland

Candida species are an important cause of nosocomial bloodstream infections in hospitalized patients worldwide, with associated high mortality, excess length of stay and costs. Main contributors to candidemias is profound immunosuppression due to serious underlying condition or intensive treatments leading to an increasing number of susceptible patients. The rank order of causative Candida species varies over time and in different geographic locations. The aim of this study was to obtain information on epidemiology of candidemia in Finland, to identify trends in incidence, causative species, and patient populations at risk. In order to reveal possible outbreaks and assess the value of one molecular typing method, restriction enzyme analysis (REA), in epidemiological study, we analyzed C. albicans bloodstream isolates in Uusimaa region in Southern Finland during eight years. The data from the National Infectious Disease Register were used to assess the incidence and epidemiological features of candidemia cases. In Helsinki University Central Hospital (HUCH) all patients with blood culture yielding any Candida spp. were identified from laboratory log-books and from Finnish Hospital Infection Program. All the patients with a stored blood culture isolate of C. albicans were identified through microbiology laboratory logbooks, and stored isolates were genotyped with REA in the National Institute for Health and Welfare (former KTL). The incidence of candidemia in Finland is globally relatively low, but increased between between 1990s and 2000s. The incidence was highest in males >65 years of age, but incidence rates for patients <1-15 years were lower during 2000s than during 1990s. In HUCH the incidence of candidemia remained low and constant during our 18 years of observation, but a significant shift in patient-populations at risk was observed, associated with patients treated in intensive care units, such as premature neonates and surgical patients. The predominating causative species in Finland and in HUCH is C. albicans, but the proportion of C. glabrata increased considerably. The crude one-month case fatality was constantly high between 28-33%. REA differentiated efficiently between C. albicans blood culture isolates and no clusters were observed in the hospitals involved, despite of abundant transfer of patients among them. Candida spp. are an important cause of nosocomial blood stream infections in Finland, and continued surveillance is necessary to determine the overall trends and patient groups at risk, and reduce the impact of these infections in the future. Molecular methods provide an efficient tool for investigation of suspected outbreak and should be available in the future in Finland, also.

Maissin tuotantoon ja markkinoihin vaikuttavat tekijät Yhdysvalloissa 2000-luvulla

Tutkimus käsittelee maissin tuotantoon ja markkinoihin vaikuttavia tekijöitä Yhdysvalloissa 2000-luvulla. Yhdysvallat on maailman merkittävin maissin tuottaja. Aikaisemmin maissia on tuotettu suoraan tai välillisesti eläinten rehuna ihmisten ruuantuotannon tarpeisiin. 2000-luvulla maissin käyttö liikenteen polttoaineena käytettävän etanolin raaka-aineena on merkittävästi lisääntynyt. Samaan aikaan maissin hinta on noussut ennätyskorkeaksi. Tässä tutkimuksessa maissimarkkinoihin vaikuttavia tekijöitä tutkittiin ajankohtaisen viranomaistiedon, aiheeseen liittyvän aikaisemman tutkimuksen ja empiirisen ekonometrisen estimoinnin perusteella. Tutkimuksen teoreettinen viitekehys perustuu kysyntä- ja tarjontateoriaan. Lisäksi tässä tutkimuksessa on kerrottu Yhdysvaltojen maatalouspolitiikan lähihistoriasta ja tarkemmin tällä hetkellä rehuviljan tuotantoon vaikuttavasta maatalouspolitiikasta. Tutkimuksessa estimoitiin maissin tuottajien viljelypäätöksiin vaikuttavia tekijöitä käyttäen pienimmän neliösumman menetelmää. Viljelypäätöstä kuvaavaksi selitettäväksi muuttujaksi valittiin maissin viljelypinta-ala. Aineiston saatavuus rajasi tutkimuksen vuosiin 1987 – 2010. Viljelypinta-alaa selittäviä muuttujia valittiin 12. Muuttujien valinta perustui maissin tuotantoon liittyviin tekijöihin, joita on käytetty muissa alan tutkimuksissa ja joiden käyttöä voidaan perustella talousteorialla. Vähitellen kokeilemalla mallista karsittiin turhat muuttujat pois ja viljelypinta-alaa selittämään jäi maissin ja soijan viivästetty hintasuhde, viivästetty typpilannoitteen hinta, maissifutuurien ostomäärät sekä viivästetty etanolin tuotanto ja maissin muu teollinen käyttö. Paras ja luotettavin lineaarisella mallilla saatu tulos sai selitysasteeksi 0,85. Tässä mallissa molemmat kysyntää kuvaavat muuttujat olivat alle 1 % virhetasolla tilastollisesti merkitseviä. Alle 10 % virhetasolla tilastollisesti merkitseviä olivat myös maissin ja soijan hintasuhde samoin kuin futuuriostot. Samoilla muuttujilla testattu log-lineaarinen malli antoi tutkimuksen korkeimman selitysasteen 0,87. Selittävistä muuttujista etanolin tuotanto oli edelleen alle 1 % virhetasolla tilastollisesti merkitsevä. Sen sijaan maissin muun teollisen käytön merkitsevyys heikkeni, ollen kuitenkin alle 10 % virhetasolla tilastollisesti merkitsevä. Lannoitteen hinnan p-arvo laski, joten lannoitteen hinta oli nyt alle 5 % virhetasolla tilastollisesti merkitsevä samoin kuin futuuriostot. Log-lineaarinen malli paransi myös maissin ja soijan hintasuhteen merkitsevyyttä. Tutkimustulokset ovat loogisia ja vastaavat teoriaa ja muita tutkimuksia siltä osin, että maissin korkeampi hinta, maissin lisääntynyt kysyntä ja futuuriostot lisäävät maissin viljelypinta-alaa. Tulosten perusteella voi todeta maissin tuotantokustannusten nousun ja soijan hinnan nousun laskevan maissin viljelypinta-alaa. Tutkimuksen tuloksena saadut joustokertoimet ovat pieniä, mikä kertoo maissin viljelypinta-alan vaihtelujen olevan melko joustamattomia markkinoilla tapahtuviin muutoksiin nähden. Tästä voisi päätellä viljelijöiden tuotantopäätösten olevan melko riippumattomia markkinoiden muutoksista. Tämä voi selittyä maatalouspolitiikan luomalla vahvalla turvaverkolla, rajoitteilla ja kannustimilla.

Exact bounds for distributed graph colouring

A distributed system is a collection of networked autonomous processing units which must work in a cooperative manner. Currently, large-scale distributed systems, such as various telecommunication and computer networks, are abundant and used in a multitude of tasks. The field of distributed computing studies what can be computed efficiently in such systems. Distributed systems are usually modelled as graphs where nodes represent the processors and edges denote communication links between processors. This thesis concentrates on the computational complexity of the distributed graph colouring problem. The objective of the graph colouring problem is to assign a colour to each node in such a way that no two nodes connected by an edge share the same colour. In particular, it is often desirable to use only a small number of colours. This task is a fundamental symmetry-breaking primitive in various distributed algorithms. A graph that has been coloured in this manner using at most k different colours is said to be k-coloured. This work examines the synchronous message-passing model of distributed computation: every node runs the same algorithm, and the system operates in discrete synchronous communication rounds. During each round, a node can communicate with its neighbours and perform local computation. In this model, the time complexity of a problem is the number of synchronous communication rounds required to solve the problem. It is known that 3-colouring any k-coloured directed cycle requires at least ½(log* k - 3) communication rounds and is possible in ½(log* k + 7) communication rounds for all k ≥ 3. This work shows that for any k ≥ 3, colouring a k-coloured directed cycle with at most three colours is possible in ½(log* k + 3) rounds. In contrast, it is also shown that for some values of k, colouring a directed cycle with at most three colours requires at least ½(log* k + 1) communication rounds. Furthermore, in the case of directed rooted trees, reducing a k-colouring into a 3-colouring requires at least log* k + 1 rounds for some k and possible in log* k + 3 rounds for all k ≥ 3. The new positive and negative results are derived using computational methods, as the existence of distributed colouring algorithms corresponds to the colourability of so-called neighbourhood graphs. The colourability of these graphs is analysed using Boolean satisfiability (SAT) solvers. Finally, this thesis shows that similar methods are applicable in capturing the existence of distributed algorithms for other graph problems, such as the maximal matching problem.

Development of foreign direct investment in Finland

During 1990 to 2009, Foreign Direct Investment (FDI henceforth) in Finland has fluctuated greatly. This paper focused on analyzing the overall development and basic characteristics of Foreign Direct Investment in Finland, covering the period from 1990 to present. By comparing FDI in Finland with FDI in other countries, the picture of Finland’s FDI position in the world market is clearer. A lot of statistical data, tables and figures are used to describe the trend of Foreign Direct Investment in Finland. All the data used in this study were obtained from Statistics Finland, UNCTAD, OECD, World Bank and International Labor Office, Investment map website and etc. It is also found that there is a big, long-lasting and increasing imbalance of the inward FDI and outward FDI in Finland, the performance of outward FDI is stronger than the inward FDI in Finland. Finland’s position of FDI in the world is rather modest. And based on existing theories, I tried to analyze the factors that might determine the size of the inflows of FDI in Finland. The econometric model of my thesis is based on time series data ranging from 1990 to 2007. A Log linear regression model is adopted to analyze the impact of each variable. The regression results showed that Labor Cost and Investment in Education have a negative influence on the FDI inflows into Finland. Too high labor cost is the main impediment of FDI in Finland, explaining the relative small size of FDI inflows into Finland. GDP and Economy openness have a significant positive impact on the inflows of FDI into Finland; other variables do not emerge as significant factor in affecting the size of FDI inflows in Finland as expected. Meanwhile, the impacts of the most recent financial and economic crisis on FDI in the world and in Finland are discussed as well. FDI inflows worldwide and in Finland have suffered from a big setback from the 2008 global crisis. The economic crisis has undoubtedly significant negative influence on the FDI flows in the world and in Finland. Nevertheless, apart from the negative impact, the crisis itself also brings in chances for policymakers to implement more efficient policies in order to create a pro-business and pro-investment climate for the recovery of FDI inflows. . The correspondent policies and measures aiming to accelerate the recovery of the falling FDI were discussed correspondently.

Sarveiskalvon permeabiliteetin ennustaminen QSPR-mallin avulla

QSPR-malli kuvaa kvantitatiivista riippuvuutta muuttujien ja biologisen ominaisuuden välillä. Näin ollen QSPR mallit ovat käyttökelpoisia lääkekehityksen apuvälineitä. Kirjallisessa osassa kerrotaan sarveiskalvon, suoliston ja veriaivoesteen permeabiliteetin malleista. Useimmin käytettyjä muuttujia ovat yhdisteen rasvaliukoisuus, polaarinen pinta-ala, vetysidosten muodostuminen ja varaus. Myös yhdisteen koko vaikuttaa läpäisevyyteen, vaikka tutkimuksissa onkin erilaista tietoa tämän merkittävyydestä. Malliin vaikuttaa myös muiden kuin mallissa mukana olevien muuttujien suuruusluokka esimerkkinä Lipinskin ‖rule of 5‖ luokittelu. Tässä luokittelussa yhdisteen ominaisuus ei saa ylittää tiettyjä raja-arvoja. Muussa tapauksessa sen imeytyminen suun kautta otettuna todennäköisesti vaarantuu. Lisäksi kirjallisessa osassa tutustuttiin kuljetinproteiineihin ja niiden toimintaan silmän sarveiskalvossa, suolistossa ja veriaivoesteessä. Nykyisin on kehitetty erilaisia QSAR-malleja kuljetinproteiineille ennustamaan mahdollisten substraatittien tai inhibiittorien vuorovaikutuksia kuljetinproteiinin kanssa. Kokeellisen osan tarkoitus oli rakentaa in silico -malli sarveiskalvon passiiviselle permeabiliteetille. Työssä tehtiin QSPR-malli 54 yhdisteen ACDLabs-ohjelmalla laskettujen muuttujien arvojen avulla. Permeabiliteettikertoimien arvot saatiin kirjallisuudesta kanin sarveiskalvon läpäisevyystutkimuksista. Lopullisen mallin muuttujina käytettiin oktanoli-vesijakaantumiskerrointa (logD) pH:ssa 7,4 ja vetysidosatomien kokonaismäärää. Yhtälö oli muotoa log10(permeabiliteettikerroin) = -3,96791 - 0,177842Htotal + 0,311963logD(pH7,4). R2-korrelaatiokerroin oli 0,77 ja Q2-korrelaatiokerroin oli 0,75. Lopullisen mallin hyvyyttä arvioitiin 15 yhdisteen ulkoisella testijoukolla, jolloin ennustettua permeabiliteettia verrattiin kokeelliseen permeabiliteettiin. QSPR-malli arvioitiin myös farmakokineettisen simulaation avulla. Simulaatiossa laskettiin seitsemän yhdisteen kammionestepitoisuudet in vivo vakaassa tilassa käyttäen simulaatioissa QSPR mallilla ennustettuja permeabiliteettikertoimia. Lisäksi laskettiin sarveiskalvon imeytymisen nopeusvakio (Kc) 13 yhdisteelle farmakokineettisen simulaation avulla ja verrattiin tätä lopullisella mallilla ennustettuun permeabiliteettiin. Tulosten perusteella saatiin tilastollisesti hyvä QSPR-malli kuvaamaan sarveiskalvon passiivista permeabiliteettia, jolloin tätä mallia voidaan käyttää lääkekehityksen alkuvaiheessa. QSPR-malli ennusti permeabiliteettikertoimet hyvin, mikä nähtiin vertaamalla mallilla ennustettuja arvoja kokeellisiin tuloksiin. Lisäksi yhdisteiden kammionestepitoisuudet voitiin simuloida käyttäen apuna QSPR-mallilla ennustettuja permeabiliteettikertoimien arvoja.

Estimation of cutting volume with three inventory methods for harvest planning in Canadian boreal forests.

Two methods of pre-harvest inventory were designed and tested on three cutting sites containing a total of 197 500 m3 of wood. These sites were located on flat-ground boreal forests located in northwestern Quebec. Both methods studied involved scaling of trees harvested to clear the road path one year (or more) prior to harvest of adjacent cut-blocks. The first method (ROAD) considers the total road right-of-way volume divided by the total road area cleared. The resulting volume per hectare is then multiplied by the total cut-block area scheduled for harvest during the following year to obtain the total estimated cutting volume. The second method (STRATIFIED) also involves scaling of trees cleared from the road. However, in STRATIFIED, log scaling data are stratified by forest stand location. A volume per hectare is calculated for each stretch of road that crosses a single forest stand. This volume per hectare is then multiplied by the remaining area of the same forest stand scheduled for harvest one year later. The sum of all resulting estimated volumes per stand gives the total estimated cutting-volume for all cut-blocks adjacent to the studied road. A third method (MNR) was also used to estimate cut-volumes of the sites studied. This method represents the actual existing technique for estimating cutting volume in the province of Quebec. It involves summing the cut volume for all forest stands. The cut volume is estimated by multiplying the area of each stand by its estimated volume per hectare obtained from standard stock tables provided by the governement. The resulting total estimated volume per cut-block for all three methods was then compared with the actual measured cut-block volume (MEASURED). This analysis revealed a significant difference between MEASURED and MNR methods with the MNR volume estimate being 30 % higher than MEASURED. However, no significant difference from MEASURED was observed for volume estimates for the ROAD and STRATIFIED methods which respectively had estimated cutting volumes 19 % and 5 % lower than MEASURED. Thus the ROAD and STRATIFIED methods are good ways to estimate cut-block volumes after road right-of-way harvest for conditions similar to those examined in this study.

Fast distributed approximation algorithms for vertex cover and set cover in anonymous networks

We present a distributed algorithm that finds a maximal edge packing in O(Δ + log* W) synchronous communication rounds in a weighted graph, independent of the number of nodes in the network; here Δ is the maximum degree of the graph and W is the maximum weight. As a direct application, we have a distributed 2-approximation algorithm for minimum-weight vertex cover, with the same running time. We also show how to find an f-approximation of minimum-weight set cover in O(f2k2 + fk log* W) rounds; here k is the maximum size of a subset in the set cover instance, f is the maximum frequency of an element, and W is the maximum weight of a subset. The algorithms are deterministic, and they can be applied in anonymous networks.

Locally checkable proofs

This work studies decision problems from the perspective of nondeterministic distributed algorithms. For a yes-instance there must exist a proof that can be verified with a distributed algorithm: all nodes must accept a valid proof, and at least one node must reject an invalid proof. We focus on locally checkable proofs that can be verified with a constant-time distributed algorithm. For example, it is easy to prove that a graph is bipartite: the locally checkable proof gives a 2-colouring of the graph, which only takes 1 bit per node. However, it is more difficult to prove that a graph is not bipartite—it turns out that any locally checkable proof requires Ω(log n) bits per node. In this work we classify graph problems according to their local proof complexity, i.e., how many bits per node are needed in a locally checkable proof. We establish tight or near-tight results for classical graph properties such as the chromatic number. We show that the proof complexities form a natural hierarchy of complexity classes: for many classical graph problems, the proof complexity is either 0, Θ(1), Θ(log n), or poly(n) bits per node. Among the most difficult graph properties are symmetric graphs, which require Ω(n2) bits per node, and non-3-colourable graphs, which require Ω(n2/log n) bits per node—any pure graph property admits a trivial proof of size O(n2).