20 research outputs found

    Autoregressive neural networks with exogenous variables for indoor temperature prediction in buildings

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    Thermal models of buildings are helpful to forecast their energy use and to enhance the control of their mechanical systems. However, these models are building-specific and require a tedious, error-prone and time-consuming development effort relying on skilled building energy modelers. Compared to white-box and gray-box models, data-driven (black-box) models require less development time and a minimal amount of information about the building characteristics. In this paper, autoregressive neural network models are compared to gray-box and black-box linear models to simulate indoor temperatures. These models are trained, validated and compared to actual experimental data obtained for an existing commercial building in Montreal (QC, Canada) equipped with roof top units for air conditioning. Results show that neural networks mimic more accurately the thermal behavior of the building when limited information is available, compared to gray-box and black-box linear models. The gray-box model does not perform adequately due to its under-parameterized nature, while the linear models cannot capture non-linear phenomena such as radiative heat transfer and occupancy. Therefore, the neural network models outperform the alternative models in the presented application, reaching a coefficient of determination R2 up to 0.824 and a root mean square error down to 1.11 °C, including the error propagation over time for a 1-week period with a 5-minute time-step. When considering a 50-hour time horizon, the best neural networks reach a much lower root mean square error of around 0.6 °C, which is suitable for applications such as model predictive control

    Conservation physiology can inform threat assessment and recovery planning processes for threatened species

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    Conservation physiology has emerged as a discipline with many success stories. Yet, it is unclear how it is currently integrated into the activities of the IUCN and other bodies which undertake international, national, or regional species threat assessments and work with partners to develop recovery plans. Here we argue that conservation physiology has much to offer for the threat assessment process and we outline the ways in which this can be operationalized. For instance, conservation physiology is effective in revealing causal relationships and mechanisms that explain observed patterns, such as population declines. Identifying the causes of population declines is a necessary precursor to the design of actions to reverse or mitigate such threats. Conservation physiology can also identify complex interactions and support modeling activities that consider emerging threats. When a population or species is deemed threatened and recovery plans are needed, physiology can be used to predict how organisms will respond to the conservation intervention and future threats. For example, if a recovery plan was focused on translocation, understanding how to safely translocate organisms would be necessary, as would ensuring that the recipient habitat provides the necessary environmental characteristics to meet the fundamental physiological needs/tolerances of that organism. Our hope is that this paper will clarify ways in which physiological data can make an important contribution to the conservation activities of bodies like the IUCN that are engaged in threat assess

    Psychosocial impact of undergoing prostate cancer screening for men with BRCA1 or BRCA2 mutations.

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    OBJECTIVES: To report the baseline results of a longitudinal psychosocial study that forms part of the IMPACT study, a multi-national investigation of targeted prostate cancer (PCa) screening among men with a known pathogenic germline mutation in the BRCA1 or BRCA2 genes. PARTICPANTS AND METHODS: Men enrolled in the IMPACT study were invited to complete a questionnaire at collaborating sites prior to each annual screening visit. The questionnaire included sociodemographic characteristics and the following measures: the Hospital Anxiety and Depression Scale (HADS), Impact of Event Scale (IES), 36-item short-form health survey (SF-36), Memorial Anxiety Scale for Prostate Cancer, Cancer Worry Scale-Revised, risk perception and knowledge. The results of the baseline questionnaire are presented. RESULTS: A total of 432 men completed questionnaires: 98 and 160 had mutations in BRCA1 and BRCA2 genes, respectively, and 174 were controls (familial mutation negative). Participants' perception of PCa risk was influenced by genetic status. Knowledge levels were high and unrelated to genetic status. Mean scores for the HADS and SF-36 were within reported general population norms and mean IES scores were within normal range. IES mean intrusion and avoidance scores were significantly higher in BRCA1/BRCA2 carriers than in controls and were higher in men with increased PCa risk perception. At the multivariate level, risk perception contributed more significantly to variance in IES scores than genetic status. CONCLUSION: This is the first study to report the psychosocial profile of men with BRCA1/BRCA2 mutations undergoing PCa screening. No clinically concerning levels of general or cancer-specific distress or poor quality of life were detected in the cohort as a whole. A small subset of participants reported higher levels of distress, suggesting the need for healthcare professionals offering PCa screening to identify these risk factors and offer additional information and support to men seeking PCa screening

    Henkilöstön vaihtuvuus ja siihen liittyvät tekijät telemarkkinointialalla : case: Gainer Oy

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    Tämä opinnäytetyö toteutettiin toimeksiantosopimuksena Gainer Oy:lle, joka on toiminut telemarkkinoinnin alalla jo vuodesta 1984. Opinnäytetyön tutkimusstrategiaksi valittiin case study eli tapaustutkimus. Käytimme tutkimusmenetelmänä kvalitatiivista eli laadullista tutkimusta. Tavoitteenamme oli tutkia ja selvittää henkilöstön vaihtuvuutta ja siihen liittyviä tekijöitä alalla, jossa henkilöstön vaihtuvuus koetaan ongelmaksi. Teoriaosuudessa käsittelemme teoreettisen viitekehyksen liittyen työnantajan keinoihin vaikuttaa työntekijän sitouttamiseen. Tämä on jaettu kahteen osa-alueeseen, jotka ovat rekrytointi sekä työhyvinvointi ja osaamisen kehittäminen. Empiirisessä osiossa päädyimme käyttämään puolistrukturoitua teemahaastattelua, joka toteutettiin suurimmaksi osaksi puhelimitse sekä muutama haastattelu tehtiin kasvotusten. Teemahaastattelu valikoitui parhaimmaksi menetelmäksi johtuen aiheen moniulotteisuudesta. Avoimella haastattelulla emme olisi välttämättä saaneet merkittävää tietoa samassa mittakaavassa kuin puolistrukturoidulla mallilla. Opinnäytetyön tuloksena päädyimme esittämään toimeksiantajalle muutamia kehitysehdotuksia. Haastatteluista johdetuilla päätelmillä saatettaisiin parantaa rekrytoinnin onnistumista, joka osaltaan parantaa kannattavuutta niin tuloksellisesti, kuin henkilöstön resurssejakin säästäen. Kehitysehdotuksia muodostui myös muihin osa-alueisiin liittyen. Näillä on myös vaikutusta henkilöstön yleiseen työhyvinvointiin ja työssä jaksamiseen.This thesis was carried out as a commission agreement for Gainer Oy, which has operated in the field of telemarketing since 1984. Our study was carried out as a case study using qualitative approach as our research method. Our objective was to study personnel turnover and matters relating to it in a field where personnel turnover is seen as a problem. In the theoretical section of the study we deal with the theoretical frame of reference related to the employer's means to influence employee engagement. This is divided into two sections that are recruiting, and occupational health and development of skills. In the empirical part of our study, we ended up using half-structured theme interviews, which were mainly carried out by telephone. A few interviews were carried out face-to-face. Theme interview was selected to be the best method because of the multidimensionality of the subject. By using open interviews, we would not necessarily have received as much significant information as by using the half-structured model. As a result of our study, we presented a few development proposals for our client/commissioner. The conclusions drawn from the interviews may lead to more successful recruiting, which in turn improves viability both in terms of productivity and by saving the resources of the personnel. There were also other development proposals concerning other areas. The results of the study may also help to improve the general well-being at work and coping with one’s workload
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