1,384 research outputs found
Dynamic Investigative Practice at the International Criminal Court
The Direct Weight Optimization (DWO) approach is a nonparametric estimation approach that has appeared in recent years within the field of nonlinear system identification. In previous work, all function classes for which DWO has been studied have included only continuous functions. However, in many applications it would be desirable also to be able to handle discontinuous functions. Inspired by the bilateral filter method from image processing, such an extension of the DWO framework is proposed for the smoothing problem. Examples show that the properties of the new approach regarding the handling of discontinuities are similar to the bilateral filter, while at the same time DWO offers a greater flexibility with respect to different function classes handled
Main haul roads, forest machine operatorâs opinions about planned proposals
BasvÀgar och basstrÄk Àr centrala delar i drivningen av en avverkningstrakt. Ett vÀl planerat basstrÄk utgör en viktig förutsÀttning för att minska körskador och i de avverkningar dÀr det Àr aktuellt, ge bra möjligheter att ta ut GROT. Med basvÀg menas den vÀg frÄn trakten ut till avlÀgg dÀr terrÀngtransporten av virket kommer att ske. BasstrÄk Àr de vÀgar inne pÄ trakten dÀr huvuddelen av virkestransporten ut till basvÀgen sker. BasstrÄken Àr ofta placerade pÄ höjdlÀgen i terrÀngen dÀr bÀrigheten Àr bÀst och Àr ofta förstÀrkta med ris för att ytterligare öka bÀrigheten. Vid planeringen av en avverkning gör planeraren förslag till en eller flera basvÀgar och ett eller flera basstrÄk. Planeraren lÀser in basvÀgarna och basstrÄken i sin handdator och snitslar vid behov dÀr det krÀvs precision. Till sin hjÀlp kan planeraren anvÀnda kartmaterial med olika skikt som bland annat kan visa markstruktur, lutning och markfuktighet. Bakgrunden till genomförandet av denna studie var att jag i mitt arbete bÄde som skotarförare och senare planerare lade mÀrke till att de planerade basvÀgs och basstrÄksförslagen ofta inte följdes. I vissa fall noterade jag till och med att de planerade förslagen inte heller gick att följa av olika orsaker. Det arbete som var nedlagt pÄ att planera basvÀgen eller basstrÄket var sÄledes bortkastat.
En tanke vÀcktes att intervjua ett antal maskinförare och höra deras Äsikter om de planerade basvÀgs- och basstrÄksförslagen och pÄ sÄ sÀtt ta reda pÄ varför förslagen inte följs, och vad som kan förbÀttras sÄ att förslagen gÄr att följa.
Studien genomfördes under maj 2017. Tio maskinförare valdes ut. Samtliga maskinförare var entreprenörer eller anstÀllda av entreprenörer som var anlitade av Stora Enso skog AB pÄ flödesomrÄde Hagge. Urvalet av förarna gjordes sedan geografiskt. MÄlet var att besöka samtliga förare ute i skogen för att genomföra intervjuerna. Samtliga intervjuer skulle genomföras under en vecka vilket gjorde att de maskinlag som valdes ut befann sig nÀra Stora Ensos kontor i Hagge vid tillfÀllet för studien. Vissa maskinförare hade dock inte möjlighet att lÄta sig intervjuas ute i skogen och intervjun fick dÄ göras via telefon.
Intervjuerna gick till sÄ, att förarna fick svara pÄ nio frÄgor utifrÄn ett frÄgeformulÀr. FrÄgorna vÀvdes i sÄ stor utstrÀckning som möjligt in i ett samtal. Vid de tillfÀllen dÄ intervjun genomfördes i fÀlt fick maskinföraren innan intervjun lÀsa igenom frÄgorna. Svaren pÄ de stÀllda frÄgorna antecknades med stödord och sammanstÀlldes senare. Svaren behandlades anonymt. FrÄgorna behandlade hur de planerade basvÀgarna och basstrÄken upplevdes samt i hur stor utstrÀckning RÀtt Metod tillÀmpades i praktiken vid drivningen av en trakt.
Maskinförarna ansÄg att de planerade basvÀgs och basstrÄksförslagen varierar mycket mellan olika planerare. De planerare som har maskinerfarenhet gör oftast bra förslag medan de planerare som inte har maskinerfarenhet gör
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betydligt sÀmre förslag. Den vanligaste orsaken till att de planerade förslagen inte följs Àr drivningstekniska faktorer. BasstrÄket eller basvÀgen gÄr inte att följa för att det Àr för kuperat, för blött eller lutar för mycket. Ofta ger inte heller det planerade förslaget optimala logistiska förutsÀttningar för skotaren, som ska ha lÀtt att fÄ fullt lass. Förarna ansÄg att planerarnas kunskap om var en maskin kan ta sig fram i terrÀngen bör förbÀttras. Förarna ansÄg Àven att de planerade förslagen i högre grad ska snitslas eftersom en linje som enbart Àr planerad med GPS i handdatorn Àr vÀldigt svÄr att följa.
Maskinförarna tillfrÄgades Àven om de ansÄg att det skulle vara bÀttre om de fick planera basvÀgar och basstrÄk sjÀlva. Majoriteten av förarna tyckte att det i vissa fall skulle vara bÀttre om de skulle göra den delen av planeringen sjÀlva men att det skulle bli en frÄga om ekonomi. StillestÄndskostnader för maskinen skulle dÄ behöva tÀckas. Förarna ansÄg dÀrför att det var bra att de planerade förslagen fanns men att de skulle ses som just förslag som vid behov kunde Àndras. Av de intervjuade förarna svarade dock 70 procent att de ÀndÄ gör nÄgon form av förplanering nÀr de kommer till en trakt, som exempelvis att snitsla basstrÄk eller stickvÀgar.
Samtliga förare ansĂ„g att rĂ€tt metod var bra. Logistiken för skotaren blev bĂ€ttre och kommunikationen inom maskinlaget förbĂ€ttrades. Förarna ansĂ„g Ă€ven att planeringen av trakterna blivit betydligt bĂ€ttre sedan metoden introducerades. Trakterna Ă€r mer genomtĂ€nkta vilket underlĂ€ttar drivningen. NĂ„gra förare ansĂ„g dock att metoden passar bĂ€ttre i slutavverkning Ă€n i gallring.The main haul roads are an important part in the transport of the wood out of a logging site to the road. The machines should be able to carry the heavy load out of the forest without damaging the ground. When the planner is planning the logging, he makes proposals, one or more, where the main haul roads can be located in the terrain. But sometimes the operators of the forest machines donât follow the planned proposals for different reasons. In this study ten forest machine operators working for Stora Enso Skog AB in Hagge, Sweden are interviewed about their opinions of the planned proposals and what they think can be change in order to improve the planned proposals. Some of the interviews was made in the forest on the logging site, and some interviews was made on telephone.
The forest machine operators think that the quality of the planned proposals varies a lot between different planners. Some planners have experience of working in a forest machine and some planners have not. The interviewed machine operators think that the proposals made by the planners that have worked in a forest machine are better than the planner that not have that experience. The main reason that the operators decide not to follow the planned proposals is often factors affected by the terrain. The ground where the planned proposal is located is to soft, to hilly or leans too much.
One important change that the machine operators think can improve the quality of the planned proposals and even the rest of the planning work is better communication between the planner and the forest machine operators. The machine operators also had a suggestion that the planners should go with the machine operator in the machine and in that way learn where the machine can go in the terrain
A Methodology for Continuous Quality Assurance of Production Data
High quality input data is a necessity for successful Discrete Event Simulation (DES) applications, and there are available methodologies for data collection in DES projects. However, in contrast to standalone projects, using DES as a day-to-day engineering tool requires high quality production data to be constantly available. Unfortunately, there are no detailed guidelines that describes how to achieve this. Therefore, this paper presents such a methodology, based on three concurrent engineering projects within the automotive industry. The methodology explains the necessary roles, responsibilities, meetings, and documents to achieve a continuous quality assurance of production data. It also specifies an approach to input data management for DES using the Generic Data Management Tool (GDM-Tool). The expected effects are increased availability of high quality production data and reduced lead time of input data management, especially valuable in manufacturing companies having advanced automated data collection methods and using DES on a daily basis
External Hydrocephalus as a Cause of Infant Subdural Hematoma: Epidemiological and Radiological Investigations of Infants Suspected of Being Abused
Background
Acute subdural hematoma (ASDH) and chronic subdural hematoma (CSDH) in infants have been regarded as highly specific for abuse. Other causes of CSDH have not been investigated in a large population.
Purpose
The purpose of this study was to investigate to what extent external hydrocephalus is present in infants with ASDH and CSDH undergoing evaluation for abuse.
Material and methods
Eighty-five infants suspected of being abused, with ASDH (n = 16) or CSDH (n = 69), were reviewed regarding age, risk factor profiles, craniocortical width (CCW), sinocortical width (SCW), frontal interhemispheric width (IHW), subarachnoid space width (SSW), and head circumference (HC). In infants with unilateral subdural hematoma (SDH), correlations between contralateral SSW and ipsilateral CCW and SDH width were investigated.
Results
Infants with CSDH had significantly lower mortality, were more often premature and male, and had significantly higher CCW, SCW, IHW, and SSW than infants with ASDH (P 5 mm, in addition to increased HC.
Conclusion
A substantial proportion of infants with CSDH who had been suspected of being abused had findings suggesting external hydrocephalus.publishedVersio
Dynamic energy system modeling using hybrid physics-based and machine learning encoderâdecoder models
Three model configurations are presented for multi-step time series predictions of the heat absorbed by the water and steam in a thermal power plant. The models predict over horizons of 2, 4, and 6 steps into the future, where each step is a 5-minute increment. The evaluated models are a pure machine learning model, a novel hybrid machine learning and physics-based model, and the hybrid model with an incomplete dataset. The hybrid model deconstructs the machine learning into individual boiler heat absorption units: economizer, water wall, superheater, and reheater. Each configuration uses a gated recurrent unit (GRU) or a GRU-based encoderâdecoder as the deep learning architecture. Mean squared error is used to evaluate the models compared to target values. The encoderâdecoder architecture is over 11% more accurate than the GRU only models. The hybrid model with the incomplete dataset highlights the importance of the manipulated variables to the system. The hybrid model, compared to the pure machine learning model, is over 10% more accurate on average over 20 iterations of each model. Automatic differentiation is applied to the hybrid model to perform a local sensitivity analysis to identify the most impactful of the 72 manipulated variables on the heat absorbed in the boiler. The models and sensitivity analyses are used in a discussion about optimizing the thermal power plant
Probing Quark Fragmentation Functions for Spin-1/2 Baryon Production in Unpolarized Annihilation
We study the measurement of the quark fragmentation functions for spin-1/2
baryon production ( and , in particular) in unpolarized
annihilation. The spin-dependent fragmentation functions
and can be probed in the process as a result of quark-antiquark
spin correlation and the weak decay of the baryons. The relevant cross section
is expressed as a product of the two-jet cross-section, the fragmentation
functions, and the differential width of the hyperon decay.Comment: 17 pages, ReVTeX with (1 figure available from authors), MIT-CTP:
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Why rapid integration policies for refugees may harm long-term integration into the labour market â especially for women
National governments typically implement a range of policies to help integrate refugees into the labour market. Drawing on a new study, Vilde Hernes, Jacob Arendt, Pernilla Joona Andersson and Kristian Rose Tronstad show that policies focused on rapid self-sufficiency for newly arrived refugees may hamper the development of stable labour-market integration in the long-term. This effect is particularly prominent in the case of women
Epidemiology of subdural haemorrhage during infancy : A population-based register study
Objectives To analyse subdural haemorrhage (SDH) during infancy in Sweden by incidence, SDH category, diagnostic distribution, age, co-morbidity, mortality, and maternal and perinatal risk factors; and its association with accidents and diagnosis of abuse. Methods A Swedish population-based register study comprising infants born between 1997 and 2014, 0-1 years of age, diagnosed with SDH-diagnoses according to the (International Classification of Diseases, 10th version (ICD10), retrieved from the National Patient Register and linked to the Medical Birth Register and the Death Cause Register. Outcome measures were: 1) Incidence and distribution, 2) co-morbidity, 3) fall accidents by SDH category, 4) risk factors for all SDHs in the two age groups, 0-6 and 7-365 days, and for ICD10 SDH subgroups: S06.5 (traumatic SDH), I62.0 (acute nontraumatic), SDH and abuse diagnosis. Results Incidence of SDH was 16.5 per 100 000 infants (n = 306). Median age was 2.5 months. For infants older than one week, the median age was 3.5 months. Case fatality was 6.5%. Male sex was overrepresented for all SDH subgroups. Accidental falls were reported in 1/3 of the cases. One-fourth occurred within 0-6 days, having a perinatal risk profile. For infants aged 7-365 days, acute nontraumatic SDH was associated with multiple birth, preterm birth, and small-for-gestational age. Fourteen percent also had an abuse diagnosis, having increased odds of being born preterm, and being small-for-gestational age. Conclusions The incidence was in the range previously reported. SDH among newborns was associated with difficult birth and neonatal morbidity. Acute nontraumatic SDH and SDH with abuse diagnosis had similar perinatal risk profiles. The increased odds for acute nontraumatic SDH in twins, preterm births, neonatal convulsions or small-for-gestational age indicate a perinatal vulnerability for SDH beyond 1st week of life. The association between prematurity/small-for-gestational age and abuse diagnosis is intriguing and not easily understood.Peer reviewe
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