793 research outputs found
The Unified-FFT Method for Fast Solution of Integral Equations as Applied to Shielded-Domain Electromagnetics
Electromagnetic (EM) solvers are widely used within computer-aided design (CAD) to improve and ensure success of circuit designs. Unfortunately, due to the complexity of Maxwell\u27s equations, they are often computationally expensive. While considerable progress has been made in the realm of speed-enhanced EM solvers, these fast solvers generally achieve their results through methods that introduce additional error components by way of geometric approximations, sparse-matrix approximations, multilevel decomposition of interactions, and more. This work introduces the new method, Unified-FFT (UFFT). A derivative of method of moments, UFFT scales as O(N log N), and achieves fast analysis by the unique combination of FFT-enhanced matrix fill operations (MFO) with FFT-enhanced matrix solve operations (MSO).
In this work, two versions of UFFT are developed, UFFT-Precorrected (UFFT-P) and UFFT-Grid Totalizing (UFFT-GT). UFFT-P uses precorrected FFT for MSO and allows the use of basis functions that do not conform to a regular grid. UFFT-GT uses conjugate gradient FFT for MSO and features the capability of reducing the error of the solution down to machine precision. The main contribution of UFFT-P is a fast solver, which utilizes FFT for both MFO and MSO. It is demonstrated in this work to not only provide simulation results for large problems considerably faster than state of the art commercial tools, but also to be capable of simulating geometries which are too complex for conventional simulation. In UFFT-P these benefits come at the expense of a minor penalty to accuracy.
UFFT-GT contains further contributions as it demonstrates that such a fast solver can be accurate to numerical precision as compared to a full, direct analysis. It is shown to provide even more algorithmic efficiency and faster performance than UFFT-P. UFFT-GT makes an additional contribution in that it is developed not only for planar geometries, but also for the case of multilayered dielectrics and metallization. This functionality is particularly useful for multi-layered printed circuit boards (PCBs) and integrated circuits (ICs). Finally, UFFT-GT contributes a 3D planar solver, which allows for current to be discretized in the z-direction. This allows for similar fast and accurate simulation with the inclusion of some 3D features, such as vias connecting metallization planes
”Joku asia liikahti maailmassa”:ihmisen ja luonnon suhde ja erilajiset toimijat Johanna Sinisalon Linnunaivot-romaanin kertomusmaailmassa
Tiivistelmä. Tässä pro gradu -tutkielmassa tarkastelen ihmisen ja ympäristön suhdetta sekä erilajisia toimijoita Johanna Sinisalon romaanissa Linnunaivot (2008). Romaanissa on sekä ihmis- että eläintoimijoita, ja myös ympäristö esitetään romaanissa toimijana. Tutkielman tarkoituksena on näyttää, miten romaani kommentoi ihmisen ja ympäristön suhdetta. Teos tuo esiin erilaisia tapoja suhtautua ympäristöön ja näyttää myös sen, miten ihmiset ja eläimet ovat monella tapaa samankaltaisia. Teoksessa myös ympäristö saa aktiivisen roolin sen sen sijaan, että se olisi vain ihmishahmojen toiminnan taustana.
Tutkielman teoreettinen tausta muodostuu ekokritiikistä, materiaalisesta ekokritiikistä sekä eläintutkimuksesta. Metodeina tutkielmassani käytän henkilöhahmoanalyysia, teoksen rakenteen ja kirjallisuudenlajin sekä intertekstuaalisuuden analyysia. Tutkielmani edustaa ekokriittistä tutkimusta, sillä tarkastelen sitä, miten ympäristö esitetään teoksessa.
Tutkielmassani tuon esiin, miten romaanin eri henkilöhahmot edustavat erilaisia tyyppejä ja sitä kautta erilaisia tapoja suhtautua ympäristöön. Näillä erilaisilla tyypeillä tuodaan esiin sitä, miten yksipuoliset tai äärimmäiset ajattelutavat voivat olla haitallisia. Joskus on tarpeen osata muuttaa omaa suhtautumistaan ja sitä kautta omaa käyttäytymistään.
Yksi romaanin teemoista on tuoda esiin lintujen viisautta ja sitä, miten linnuilla on yllättävän paljon samanlaisia ominaisuuksia kuin ihmisilläkin. Tähän viittaa romaanin nimi Linnunaivot. Vertailemalla ihmis- ja eläinhahmoja toisiinsa tuon esille sen, että romaanin linnuilla ja ihmisillä on samanlaisia ominaisuuksia ja ne käyttäytyvät yllättävän samanlaisesti.
Kun tarkastellaan ympäristön kuvausta teoksessa, tulee esiin, että ympäristö esitetään sekä kielen että tarinan tasolla romaanissa toimijana. Ympäristöä ja eri henkilöhahmoja tarkastellessa tulee esille myös ajatus siitä, että mikään toimija ei toimi itsenäisesti, vaan sekä romaanin hahmot että ympäristö toimivat kaikki vuorovaikutuksessa keskenään.
Yksi tärkeistä teemoista romaanissa on matkustaminen, matkustamisen syyt ja siihen liittyvät ongelmat. Teoksen pohjatekstinä toimii Joseph Conradin teos Pimeyden sydän (1902). Kahdessa teoksessa tapahtuvat matkat rinnastetaan sekä ympäristön kielellisen kuvauksen tasolla että temaattisella tasolla. Molemmissa teoksissa ympäristö kuvataan toimijana, uhkaavana oliona, joka ei toivota sinne matkustavia tervetulleeksi.
Teoksessa otetaan kantaa siihen, miten ympäristöä tulisi kohdella. Erämaahan matkustamista tulisi harkita tarkkaan, sillä siitä on aina ympäristölle haittaa. Tasmanian erämaa alkaa olla vaarassa, kun matkustajamäärät nousevat jatkuvasti. Lisäksi teoksessa käsitellään myös Suomea ja Lappia, jota uhkaavat täsmälleen samat turismiin ja luonnon köyhtymiseen liittyvät ongelmat kuin Australiaakin
Yhtenäisen myyntitapaamiskonseptin mahdollistavat tekijät
Tiivistelmä. Myyntitapaaminen on lähes ainut yrityksen myyntiprosessista asiakkaalle näkyvä osa. Tämän tutkimuksen tavoite on selvittää miten yrityksen myyntitapaamisten ohjaaminen ja johtaminen voidaan yrityksissä toteuttaa yhtenäisesti.
Tutkimuksen teoriaosiossa tutkitaan miten myyntitapaaminen on sijoitettu myynnin tutkimuksessa sekä miten prosessijohtamisen tutkimuksessa on tutkittu yhtenäistä toimintatapaa.
Tämä tutkimus on tehty toimintatutkimuksena avoimilla puolistrukturoiduilla haastatteluilla. Ainestoa on lisäksi analysoitu sisällönanalyysin menetelmällä. Tutkimus on tehty laadullisin menetelmin, johon on haastateltu 7 henkilöä. Tämä tutkimus on tehty teknisenä toimintatutkimuksena, jossa haastatteluja on käytetty tutkijan apuna syventää ymmärrystä ja ratkaista tutkittua ongelmaa.
Tämän tutkimuksen perusteella yhtenäistä toimintatapaa ole vielä laajassa mittakaavassa toteutettu. Toimintatutkimuksen tuloksena löydettiin kuitenkin neljä merkittävintä tekijää, joiden perusteella muodostettiin prosessijohtamisen teoriaa hyödyntäen malli myyntitapaamiskonseptista. Lisäksi muodostettiin ratkaisumyynnin portaat-malli, joka kuvaa yritysten myyntitapaamisten tyypillistä etenemistä.
Tutkimus suunta ja tulokset rikastavat nykyistä kirjallisuutta tuoden esille myyntitapaamisen johtamisen yksittäisenä osana yrityksen myyntiprosessista. Tärkein tutkimuksen tavoite oli tehdä näkyväksi ja sanoittaa miten myyntijohdon tulee myyntitapaamisia ohjaa ja johtaa. Myyntitapaamisen merkitys ja rooli yrityksen myynnissä korostuu ja siellä työskentelevien henkilöiden ammattitaitoa tulee pystyä johtamaan ja kehittämään.Enabling factors for a unified sales meeting concept. Abstract. A sales meeting is almost the only part of the company’s sales process visible to a customer. The study aims to find out how important it is to implement the guidance and management of sales meetings in a unified manner.
The study theory section examines how a sales meeting ranks in market research and how process management research examines a unified approach.
This study is conducted as an action study with open-structured interviews. The material is available analyzed by the content analysis method. The study was conducted using qualitative methods, where seven people were interviewed. This study has been conducted as a technical action study, which is why the interviews have been used to help the researcher deepen their understanding and solve the problem studied.
Based on this study, a unified approach has not yet been implemented on a large scale. However, as a result of the action research, the four most significant factors were found, on the basis of which a model of the sales meeting concept was formed, utilizing the theory of process management. In addition, a solution sales ladder model was developed that describes the typical progress of companies’ sales meetings.
The research direction and results enrich the current literature by highlighting sales meeting management as a single part of a company’s sales process. The main goal of the study was to make visible and say how sales management should direct and lead sales meetings. The importance and role of the sales meeting in the company’s sales is emphasized, and the professional skills of the people working there must be able to be managed and developed
Transcriptional monitoring of steady state and effects of anaerobic phases in chemostat cultures of the filamentous fungus Trichoderma reesei
BACKGROUND: Chemostat cultures are commonly used in production of cellular material for systems-wide biological studies. We have used the novel TRAC (transcript analysis with aid of affinity capture) method to study expression stability of approximately 30 process relevant marker genes in chemostat cultures of the filamentous fungus Trichoderma reesei and its transformant expressing laccase from Melanocarpus albomyces. Transcriptional responses caused by transient oxygen deprivations and production of foreign protein were also studied in T. reesei by TRAC. RESULTS: In cultures with good steady states, the expression of the marker genes varied less than 20% on average between sequential samples for at least 5 or 6 residence times. However, in a number of T. reesei cultures continuous flow did not result in a good steady state. Perturbations to the steady state were always evident at the transcriptional level, even when they were not measurable as changes in biomass or product concentrations. Both unintentional and intentional perturbations of the steady state demonstrated that a number of genes involved in growth, protein production and secretion are sensitive markers for culture disturbances. Exposure to anaerobic conditions caused strong responses at the level of gene expression, but surprisingly the cultures could regain their previous steady state quickly, even after 3 h O(2 )depletion. The main effect of producing M. albomyces laccase was down-regulation of the native cellulases compared with the host strain. CONCLUSION: This study demonstrates the usefulness of transcriptional analysis by TRAC in ensuring the quality of chemostat cultures prior to costly and laborious genome-wide analysis. In addition TRAC was shown to be an efficient tool in studying gene expression dynamics in transient conditions
Laparoscopic ventral rectopexy in male patients with external rectal prolapse is associated with a high reoperation rate
Background Laparoscopic ventral rectopexy has been used to treat male patients with external rectal prolapse, but evidence to support this approach is scarce. The aim of this study was to evaluate the results of this new abdominal rectopexy surgical technique in men. Methods This was a retrospective multicenter study. Adult male patients who were operated on for external rectal prolapse using ventral rectopexy in five tertiary hospitals in Finland between 2006 and 2014 were included in the study. Patient demographics, detailed operative, postoperative and short-term follow-up data were collected from patient registers in participating hospitals. A questionnaire and informed consent form was sent to all patients. The questionnaire included scores for anal incontinence, obstructed defecation syndrome, urinary symptoms and sexual dysfunction. The main outcome measure was the incidence of recurrent rectal prolapse. Surgical morbidity, the need for surgical repair due to recurrent symptoms and functional outcomes were secondary outcome measures. Results A total of 52 adult male patients with symptoms caused by external rectal prolapse underwent ventral rectopexy. The questionnaire response rate was 64.4 %. Baseline clinical characteristics and perioperative results were similar in the responder and non-responder groups. A total of 9 (17.3 %) patients faced complications. There were two (3.8 %) serious surgical complications during the 30-day period after surgery that necessitated reoperation. None of the complications were mesh related. Recurrence of the prolapse was noticed in nine patients (17 %), and postoperative mucosal anal prolapse symptoms persisted in 11 patients (21 %). As a result, the reoperation rate was high. Altogether, 17 patients (33 %) underwent reoperation during the follow-up period due to postoperative complications or recurrent rectal or mucosal prolapse. According to the postoperative questionnaire data, patients under 40 had good functional results in terms of anal continence, defecation, urinary functions and sexual activity. Conclusions Laparoscopic ventral rectopexy is a safe surgical procedure in male patients with external prolapse. However, a high overall reoperation rate was noticed due to recurrent rectal and residual mucosal prolapse. This suggests that the ventral rectopexy technique should be modified or combined with other abdominal or perineal methods when treating male rectal prolapse patients.Peer reviewe
Redo ventral rectopexy : is it worthwhile?
Background Minimally invasive ventral mesh rectopexy (VMR) is a widely used surgical treatment for posterior pelvic organ prolapse; however, evidence of the utility of revisional surgery is lacking. Our aim was to assess the technical details, safety and outcomes of redo minimally invasive VMR for patients with external rectal prolapse (ERP) recurrence or relapsed symptoms of internal rectal prolapse (IRP). Methods This is a retrospective cohort study of patients with recurrent ERP or symptomatic IRP who underwent redo minimally invasive VMR between 2011 and 2016. The study was conducted at three hospitals in Finland. Data collected retrospectively included patient demographics, in addition to perioperative and short-term postoperative findings. At follow-up, all living patients were sent a questionnaire concerning postoperative disease-related symptoms and quality of life. Results A total of 43 redo minimally invasive VMR were performed during the study period. The indication for reoperation was recurrent ERP in 22 patients and relapsed symptoms of IRP in 21 patients. In most operations (62.8%), the previously used mesh was left in situ and a new one was placed. Ten (23.3%) patients experienced complications, including 2 (4.7%) mesh-related complications. The recurrence rate was 4.5% for ERP. Three patients out of 43 were reoperated on for various reasons. One patient required postoperative laparoscopic hematoma evacuation. Patients operated on for recurrent ERP seemed to benefit more from the reoperation. Conclusions Minimally invasive redo VMR appears to be a safe and effective procedure for treating posterior pelvic floor dysfunction with acceptable recurrence and reoperation rates.Peer reviewe
Constraining the top-light initial mass function in the extended ultraviolet disk of M83
The universality or non-universality of the initial mass function (IMF) has
significant implications for determining star formation rates and star
formation histories from photometric properties of stellar populations. We
reexamine whether the IMF is deficient in high-mass stars (top-light) in the
low-density environment of the outer disk of M83 and constrain the shape of the
IMF therein. Using archival Galaxy Evolution Explorer (GALEX) far ultraviolet
(FUV) and near ultraviolet (NUV) data and new deep OmegaCAM narrowband
H imaging, we constructed a catalog of FUV-selected objects in the
outer disk of M83. We counted H-bright clusters and clusters that are
blue in FUVNUV in the catalog, measured the maximum flux ratio
among the clusters, and
measured the total flux ratio over the catalog. We then compared these measurements to
predictions from stellar population synthesis models made with a standard
Salpeter IMF, truncated IMFs, and steep IMFs. We also investigated the effect
of varying the assumed internal extinction on our results. We are not able to
reproduce our observations with models using the standard Salpeter IMF or the
truncated IMFs. It is only when assuming an average internal extinction of
in the outer disk stellar clusters that models
with steep IMFs () simultaneously reproduce the observed cluster
counts, the maximum observed ,
and the observed .
Our results support a non-universal IMF that is deficient in high-mass stars in
low-density environments.Comment: 18 pages, 15 figures, accepted to Astronomy & Astrophysic
Effects of overstory tree density, site preparation, and ground vegetation on natural Scots pine seedling emergence and survival in northern boreal pine forests
Natural regeneration is a commonly used forest regeneration method in northern Finland. It is not known, however, what would be the optimal overstory density and ground vegetation composition for seedling emergence and survival, and if site preparation is needed to accompany overstory density manipulation. We studied the effects of overstory density (unthinned control and thinning to 50,150, and 250 trees.ha(-1)) and ground vegetation removal (mechanical site preparation with disc trenching) on the number of naturally germinated pine seedlings and survival of individual seedlings over a period of 8 to 11 years. Bare mineral soil was a superior seedbed compared to intact vegetation cover, even though the mortality rate was high on mineral soil. Greater cover of lingonberry, crowberry, and slash had a negative effect on seedling number. Seedling mortality was initially high (60% died during the first 2 years) but decreased throughout the first 5 years. The survival rate of seedlings located in the mineral soil of the upper part of the disc trencher track was twice as high as that of seedlings located in the lower part of the track. High coverage of hair mosses (Polytrichum spp.) was associated with poorer seedling survival. An overstory density of 50-150 trees.ha(-1) with site preparation seems to be an efficient treatment to promote regeneration under these circumstances
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