Effects of vane/blade ratio and spacing on fan noise, volume 1

The noise characteristics of a high-speed fan were studied. The experimental investigation was carried out on a 50.8 cm (20 in.) diameter scale model fan stage in an anechoic chamber with an inflow turbulence control screen installed. The forty-four blade rotor was tested with forty-eight vane and eighty-six vane stator rows, over a range of aixal rotor-stator spacings from 0.5 to 2.3 rotor tip chords. A two-dimensional strip theory model of rotor-stator interaction noise was employed to predict the measured tone power level trends, and good overall agreement with measured trends was obtained

Basic research in fan source noise: Inlet distortion and turbulence noise

A widely recognized problem in jet engine fan noise is the discrepancy between inflight and static tests. This discrepancy consists of blade passing frequency tones, caused by ingested turbulence that appear in the static tests but not in flight. To reduce the ingested distortions and turbulence in an anechoic chamber, a reverse cone inlet is used to guide the air into the fan. This inlet also has provisions for boundary layer suction and is used in conjunction with a turbulence control structure (TCS) to condition the air impinging on the fan. The program was very successful in reducing the ingested turbulence, to the point where reductions in the acoustic power at blade passing frequency are as high as 18 db for subsonic tip speeds. Even with this large subsonic tone suppression, the supersonic tip speed tonal content remains largely unchanged, indicating that the TCS did not appreciably attenuate the noise but effects the generation via turbulence reduction. Turbulence mapping of the inlet confirmed that the tone reductions are due to a reduction in turbulence, as the low frequency power spectra of the streamwise and transverse turbulence were reduced by up to ten times and 100 times, respectively

Tackling the emotional toll together : how journalists address harassment with connective practices

In this article, we examine how journalists address and tackle online harassment by connective practices that involve joint action with peers and editors that we find are particularly effective in addressing the emotional effects of harassment. Theoretically, we bridge community of practice research with theories of emotional labour to develop a novel perspective to examine online harassment. Drawing on 22 interviews with Finnish journalists, we find three categories of connective practices that are particularly effective in tackling harassment: (1) supportive connection between the journalist and the editor; (2) shared collegial practices among peers in the newsrooms and (3) emotional engagement among peers outside the newsroom. All three categories illustrate how journalists as a community of practice develop new practices through dynamic processes innovation, improvisation, trial and error, reciprocal learning and mutual engagement. Importantly, emotional labour forms an important dimension of these practices as the journalists jointly address and tackle the emotional effects of harassment. We posit that the effectiveness of these connective practices largely stems from their ability to provide emotional support. While addressing feelings of fear, anger and shame, these shared practices also help consolidate the newly acquired knowledge and the professional identity under attack. Finally, we offer recommendations for newsrooms and journalists on how to collectively counter harassment and develop policies to address it.Peer reviewe

Effects of vane/blade ratio and spacing on fan noise. Volume 2: Data supplement

Complete tabulations of 1/3-octave band acoustic measurements are given

Aqueous modification of chitosan with itaconic acid to produce strong oxygen barrier film

In this study, the chemical modification of chitosan using itaconic acid as a natural-based unsaturated dicarboxylic acid was investigated. In an aqueous environment, the amine group of chitosan reacts with itaconic acid to produce a chitosan derivative with pyrrolidone-4-carboxylic acid group. On the basis of the elemental analysis, 15 of the amine groups of chitosan reacted, thus creating modified chitosan with amine and carboxylic acid functionalities. Due to the presence of amine and carboxylic acid groups, the surface charge properties of the chitosan were notably altered after itaconic acid modification. In an aqueous solution, the modified chitosan exhibited zwitterionic properties, being cationic at low pH and turning anionic when the pH was increased over 6.5, whereas the original chitosan remained cationic until pH 9. Furthermore, it was demostrated that the modified chitosan was suitable for the preparation of a self-standing film with similarly high transparency but notably higher mechanical strength and oxygen barrier properties compared to a film made from the original chitosan. In addition, the thermal stability of the modified chitosan film was higher than that of the original chitosan film, and the modified chitosan exhibited flame-retardant properties

”Luokkakuva suhisi ja sihisi pinkkejä Dingo-huiveja”:nuoruus 1980-luvulla omaelämänkerrallisten tekstien kuvaamana

Tiivistelmä. Suomalaisessa muistitietoon pohjautuvassa nuorisotutkimuksessa ”kasarinuoret” ovat vielä melko vähän tutkittu aihe. Vanhempia sukupolvia ja erityisesti toisen maailmansodan jälkeen syntyneitä suuria ikäluokkia on tutkittu runsaasti, joiden varjoon nuoremmat ovat tutkimuksen kohteena jääneet. Tähän tarpeeseen vastaamiseksi tutkin tässä pro gradu -työssä sitä, miten 1980-luvulla nuoruutensa eläneet muistelevat nuoruuttaan omaelämänkerrallisissa teksteissä. Aineistona käytän Nuorisotutkimusverkoston, Nuoren Voiman Liiton ja Suomalaisen Kirjallisuuden seuran 15.5.–30.11.2010 järjestämän omaelämänkerrallisen Oi nuoruus -kirjoituskilpailun tuotoksia. Aineiston olen rajannut siten, että se koostuu vuosina 1965–1975 syntyneiden kirjoittajien teksteistä. Tällä rajauksella aineistoni koostuu 36 kirjoituksesta. Yhteensä kilpaluun lähetettiin 376 teksti. Naiset ovat aineistossani selvästi yliedustettuina, sillä kirjoituksista vain kahdeksan oli miesten kirjoittamia. Tämä epäsuhta heijastuu tutkimustuloksiini. Tutkimukseni kohde on nuoruus kokemuksena ja ilmiönä — keskiössä ovat kysymykset siitä, miten nuoruutta muistellaan ja mitä asioita näistä muistoista nousee esille. Luonteeltaan tutkimukseni on pääasiassa kvalitatiivinen, keskeisimpänä tutkimusmenetelmänäni on aineiston lähiluku. Aineisto luetaan useaan kertaan, jolloin sieltä tunnistetaan tutkimustehtävän kannalta keskeisiä elementtejä ja näiden pohjalta tehdään tulkinnat. Aineiston perusteella kirjoittajat muistelevat nuoruuttaan erityisesti nuoruuteen liittyvien siirtymien ja merkkipaalujen sekä nuorisokulttuurin kautta. Koulutaival oli monen kirjoittajan muistoissa keskeinen osa nuoruutta, ja varsinkin siirtymä yläasteelle koettiin tärkeäksi tapahtumaksi. Ensimmäiset päihdekokeilut ja ensiaskeleiden ottaminen vastakkaisen sukupuolen kanssa olivat kaksi muuta aineistosta selvästi erottuvaa merkkipaalua. Keskeisin nuoruuskokemuksia yhdistävä tekijä oli kuitenkin nuorisokulttuuri ja erityisesti musiikki, joka korostui muistoissa ja kietoutui myös muille elämän osa-alueille. 1980-luvun nuoruusmuistoissa on vielä runsaasti tutkittavaa. Tässä tutkielmassa keskeisimmäksi haasteeksi nousi aineiston rajallisuus ja sen homogeeninen luonne, minkä myötä tutkimani muistot ovat pääasiassa koulutettujen, naispuolisten henkilöiden muistoja

Measuring Student Engagement and Commitment on Private Academic Institutions Using Fuzzy Logic Expert System Metrics Applications

Even though academic knowledge is provided to academic institutions under very specific academic standards in teaching and research, the instruction’s management can impact significantly the student engagement and commitment on receiving and utilizing such knowledge. To analyse this challenge, a Fuzzy Logic, expert system-based software application has been developed and applied on a private academic institution. In this research the institution participated with 40 undergraduate students, from 24 different countries from two different semesters on the same course. The technology measures the student engagement and commitment via the co-evolute methodology for knowledge elicitation. By utilizing this approach, the management of academic institutions can make development analysis based on concrete bottom-up results. The collective analysis of the test results clearly identifies where students see the needs for greatest development and how they view their current state of engagement

Phronetic leadership style evaluation with a fuzzy logic application

The purpose of leadership style assessments is to determine the basic features and characteristics of leadership behaviours and to reveal the leader’s personality traits and abilities and to increase their self-awareness. The style can be, for example, democratic, autocratic, bureaucratic, laissez-faire, strategic, visionary, transformational, or transactional. However, ordinary assessments do not help leaders analyze their knowledge and wisdom behind their behaviours. The Wisdom Cube seeks to explain wisdom through the four dimensions of wisdom and provides a practical way of understanding the knowledge and wisdom in leadership. By utilising the dimensions and planes of the Wisdom Cube, we can find the way from data handling, information processing, and knowledge creation to wisdom generation. The aim of this research is, therefore, to reveal the ontology of the phronetic leader and to create a practical evaluation tool for leaders. The content of the article covers the elements of the Wisdom Cube, presents related efforts to measure and analyze phronetic leadership characteristics, and shows the practical results of the first test runs with the fuzzy logic-based application. The personal deep understanding of the leadership traits may then help the leaders to turn their current leadership styles more phronetic

Normalization of large-scale behavioural data collected from zebrafish

Many contemporary neuroscience experiments utilize high-throughput approaches to simultaneously collect behavioural data from many animals. The resulting data are often complex in structure and are subjected to systematic biases, which require new approaches for analysis and normalization. This study addressed the normalization need by establishing an approach based on linear-regression modeling. The model was established using a dataset of visual motor response (VMR) obtained from several strains of wild-type (WT) zebrafish collected at multiple stages of development. The VMR is a locomotor response triggered by drastic light change, and is commonly measured repeatedly from multiple larvae arrayed in 96-well plates. This assay is subjected to several systematic variations. For example, the light emitted by the machine varies slightly from well to well. In addition to the light-intensity variation, biological replication also created batch-batch variation. These systematic variations may result in differences in the VMR and must be normalized. Our normalization approach explicitly modeled the effect of these systematic variations on VMR. It also normalized the activity profiles of different conditions to a common baseline. Our approach is versatile, as it can incorporate different normalization needs as separate factors. The versatility was demonstrated by an integrated normalization of three factors: light-intensity variation, batch-batch variation and baseline. After normalization, new biological insights were revealed from the data. For example, we found larvae of TL strain at 6 days post-fertilization (dpf) responded to light onset much stronger than the 9-dpf larvae, whereas previous analysis without normalization shows that their responses were relatively comparable. By removing systematic variations, our model-based normalization can facilitate downstream statistical comparisons and aid detecting true biological differences in high-throughput studies of neurobehaviour