953 resultados para Next-to-leading orders
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We report calculations of energy levels and oscillator strengths for transitions in W XL, undertaken with the general-purpose relativistic atomic structure package (GRASP) and flexible atomic code (FAC). Comparisons are made with existing results and the accuracy of the data is assessed. Discrepancies with the most recent results of S. Aggarwal et al. (Can. J. Phys. 91, 394 (2013)) are up to 0.4 Ryd and up to two orders of magnitude for energy levels and oscillator strengths, respectively. Discrepancies for lifetimes are even larger, up to four orders of magnitude for some levels. Our energy levels are estimated to be accurate to better than 0.5% (i.e., 0.2 Ryd), whereas results for oscillator strengths and lifetimes should be accurate to better than 20%.
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We report calculations of energy levels, radiative rates, oscillator strengths and line strengths for transitions among the lowest 231 levels of Ti VII. The general-purpose relativistic atomic structure package and flexible atomic code are adopted for the calculations. Radiative rates, oscillator strengths and line strengths are provided for all electric dipole (E1), magnetic dipole (M1), electric quadrupole (E2) and magnetic quadrupole (M2) transitions among the 231 levels, although calculations have been performed for a much larger number of levels (159 162). In addition, lifetimes for all 231 levels are listed. Comparisons are made with existing results and the accuracy of the data is assessed. In particular, the most recent calculations reported by Singh et al (2012 Can. J. Phys. 90 833) are found to be unreliable, with discrepancies for energy levels of up to 1 Ryd and for radiative rates of up to five orders of magnitude for several transitions, particularly the weaker ones. Based on several comparisons among a variety of calculations with two independent codes, as well as with the earlier results, our listed energy levels are estimated to be accurate to better than 1% (within 0.1 Ryd), whereas results for radiative rates and other related parameters should be accurate to better than 20%.
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The purpose of this study was to explore nurses' perceptions of their current practices related to administering pain medications to long-term care (LTC) residents. A cross-sectional survey design was used, including both quantitative and open-ended questions. Data were collected from 165 nurses (59% response rate) at nine LTC homes in southern Ontario, Canada. The majority (85%) felt that the medication administration system was adequate to help them manage residents' pain and 98% felt comfortable administering narcotics. In deciding to administer a narcotic, nurses were influenced by pain assessments, physician orders, diagnosis, past history, effectiveness of non-narcotics and fear of making dosage miscalculations or developing addictions. Finally, most nurses stated that they trusted the physicians and pharmacists to ensure orders were safe. These findings highlight nurses' perceptions of managing pain medications in LTC and related areas where continuing education initiatives for nurses are needed.
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In this study we investigate the influence of the implementation of multidimensional engagement on students’ academic, social and emotional outcomes in the teaching of Operations and Supply Chain Management (OSCM) modules. Next to the academic and behavioural engagement dimensions, which are traditionally used to engage students in OSCM courses, we also incorporate a cognitive dimension to enhance integral student engagement. Up to know, integral student engagement is not reported in the OSCM literature. Cognitive engagement is based on implementation of summative self- and peer-assessment of weekly assignments. Our investigation is based on action research, conducted in an OSCM module over two consecutive years. We found that, in general, multidimensional engagement results in higher levels of academic performance, development of relationships with academic staff and their peers and emotional satisfaction. These findings are discussed in relation to several contextual factors: nature of the study material, gender, and the home location of students.
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Field programmable gate array devices boast abundant resources with which custom accelerator components for signal, image and data processing may be realised; however, realising high performance, low cost accelerators currently demands manual register transfer level design. Software-programmable ’soft’ processors have been proposed as a way to reduce this design burden but they are unable to support performance and cost comparable to custom circuits. This paper proposes a new soft processing approach for FPGA which promises to overcome this barrier. A high performance, fine-grained streaming processor, known as a Streaming Accelerator Element, is proposed which realises accelerators as large scale custom multicore networks. By adopting a streaming execution approach with advanced program control and memory addressing capabilities, typical program inefficiencies can be almost completely eliminated to enable performance and cost which are unprecedented amongst software-programmable solutions. When used to realise accelerators for fast fourier transform, motion estimation, matrix multiplication and sobel edge detection it is shown how the proposed architecture enables real-time performance and with performance and cost comparable with hand-crafted custom circuit accelerators and up to two orders of magnitude beyond existing soft processors.
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Tese de doutoramento, Ciências Agrárias (Proteção de Plantas), Faculdade de Ciência e Tecnologia, Universidade do Algarve, 2014
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Tese de doutoramento, Ciências Biotecnológicas (Biotecnologia Alimentar), Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2014
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Der vorliegende Artikel bezieht sich auf die unterschiedlichen Begrifflichkeiten, die im Umfeld der Wettbewerberforschung in der Literatur Verwendung finden. Neben den Begriffen des angloamerikanischen Sprachraums (Competitive Intelligence, Competitor Intelligence und Competitor Analyse) existieren für den deutschsprachigen Raum (Wettbewerber-, Konkurrenten-, Wettbewerbs- und Konkurrenzanalyse) ebenfalls verschiedenartige Begriffe, denen in der Literatur eine häufig unterschiedliche Verwendung zu Teil wird. Dieser Artikel baut einen Ordnungsansatz auf, der die angesprochenen Begrifflichkeiten in eine Struktur bringt, um somit eine klare inhaltliche Trennung der einzelnen Begriffe sowie eine in Relation bringende Darstellung aufbauen zu können. Dies ermöglicht eine ambiguitätsfreie Verwendung innerhalb der wissenschaftlichen Arbeit durch definitorisch fixierte Begriffsinhalte.
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Relatório de estágio de mestrado, Estudos Regionais e Autárquicos, Universidade de Lisboa, Faculdade de Letras, 2012
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Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Mecânica
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Transport is an essential sector in modern societies. It connects economic sectors and industries. Next to its contribution to economic development and social interconnection, it also causes adverse impacts on the environment and results in health hazards. Transport is a major source of ground air pollution, especially in urban areas, and therefore contributing to the health problems, such as cardiovascular and respiratory diseases, cancer, and physical injuries. This thesis presents the results of a health risk assessment that quantifies the mortality and the diseases associated with particulate matter pollution resulting from urban road transport in Hai Phong City, Vietnam. The focus is on the integration of modelling and GIS approaches in the exposure analysis to increase the accuracy of the assessment and to produce timely and consistent assessment results. The modelling was done to estimate traffic conditions and concentrations of particulate matters based on geo-references data. A simplified health risk assessment was also done for Ha Noi based on monitoring data that allows a comparison of the results between the two cases. The results of the case studies show that health risk assessment based on modelling data can provide a much more detail results and allows assessing health impacts of different mobility development options at micro level. The use of modeling and GIS as a common platform for the integration of different assessments (environmental, health, socio-economic, etc.) provides various strengths, especially in capitalising on the available data stored in different units and forms and allows handling large amount of data. The use of models and GIS in a health risk assessment, from a decision making point of view, can reduce the processing/waiting time while providing a view at different scales: from micro scale (sections of a city) to a macro scale. It also helps visualising the links between air quality and health outcomes which is useful discussing different development options. However, a number of improvements can be made to further advance the integration. An improved integration programme of the data will facilitate the application of integrated models in policy-making. Data on mobility survey, environmental monitoring and measuring must be standardised and legalised. Various traffic models, together with emission and dispersion models, should be tested and more attention should be given to their uncertainty and sensitivity
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RESUMO: Na descrição deste estudo foi utilizada a terminologia anatómica da Sociedade Brasileira de Anatomia adaptada ao português por J. A. Esperança-Pina de acordo com o tratado Anatomia Humana da Relação. Os actuais estudos sobre hipoacusia sensorioneural implicam um grupo crescente de situações, em que a lesão se situa ao nível da microvascularização coclear, daí que o conhecimento exacto da angiomorfologia normal se torne essencial na fase actual do conhecimento. A autora tem vindo a estudar, desde 1986, a angiomorfologia do ouvido Interno no modelo experimental, o Cobaio, utilizando várias técnicas microvasculares. sendo dado enfâse particular neste estudo à técnica de microscopia electrónica de varrimento em moldes vasculares. Os animais usados no presente estudo pertencem à espécie cavia porcellus, cobaio, por serem considerados na comunidade cientifica internacional como o melhor modelo experimental para estudo do ouvido interno, pelo facto de a morfologia coclear ser muito semelhante à do Homem e por isso ser um modelo fiável para cirurgia experimental e microdissecção. Este estudo foi realizado em 100 cobaios, cavia porcellus, de ambos os sexos com peso médio de 450g. A vascularização do ouvido interno, no cobaio como no homem, faz-se através dos ramos de divisão da artéria auditiva interna ou labiríntica. A artéria labiríntica origina-se como ramo colateral da artéria cerebelosa ântero-inferior a qual tem origem na artéria basilar ou na artéria vertebral. Embora no homem a artéria auditiva interna possa também destacar-se da artéria basilar e até da artéria vertebral, no cobaio em todos os casos estudados a sua origem verificou-se sempre na artéria cerebelosa ântero-inferior. A artéria labiríntica, ao passar abaixo do meato auditivo interno, divide-se na artéria vestibular anterior e na artéria coclear comum.A artéria vestibular anterior dirige-se para o nervo vestibular, emite vasa nervorum para este nervo e vasculariza o utrículo e os canais semicirculares. A artéria coclear comum origina dois ramos principais, a artéria vestíbulo‑coclear ou vestibular posterior no cobaio, a qual se destaca junto à espira basal da cóclea e a artéria coclear, como ramo terminal, que passa a denominar-se de artéria modiolar ou espiralada, após entrar no modíolo. A artéria modiolar ascende no modíolo promovendo através dos seus ramos colaterais e dos seus ramos terminais a microvascularização coclear, numa vascularização de órgão de tipo terminal. Ao longo do seu trajecto verificou‑se de modo constante uma redução gradual de calibre em cada uma das espiras, por emissão de ramos colaterais, sendo que o calibre da artéria na base da cóclea apresenta um valor que diminui gradualmente até ao ápice. A artéria modiolar origina em todo o seu trajecto ramos colaterais, cujo número diminui em valor absoluto da base para o ápice: Arteríolas radiárias internas, arteríolas de trajecto flexuoso que caminham junto às estruturas sensorioneurais da parede interna da cóclea, junto ao lábio timpânico da lâmina espiral óssea e na parede do próprio modíolo, que se relacionam intimamente com este. As arteríolas radiárias internas originam‑se no flanco da artéria modiolar espiralada. Contam‑se dez a doze em cada espira, extraordinariamente flexuosas desde a sua origem. As arteríolas radiárias internas originam como ramos colaterais, vários grupos de arteríolas de menor calibre, que vascularizam distintas regiões da parede interna da cóclea, as arteríolas do gânglio espiral, a rede espiral interna, as arteríolas de origem dos glomérulos de Schwalbe e a arteríola da lâmina basilar. As arteríolas radiárias externas importantes ramos colaterais da artéria modiolar espiralada promovem a vascularização de importantes estruturas da parede externa. Ao atingir o limite externo do ligamento espiral, as arteríolas radiárias externas dividem‑se em vários ramos arteriolares de menor calibre, ao longo da convexidade do limite externo do ligamento espiral, originando a rede capilar pós-estriada que ocupa a porção lateral do ligamento espiral e a rede capilar ad‑ -estriada, na sua porção mais medial em íntima relação com a estria vascular. A espira basal da cóclea apresenta grande riqueza de vascularização, com características particulares apenas a esta espira, a qual é metabolicamente a mais exigente. A arteríola da janela da cóclea aborda a janela da cóclea pela sua convexidade e divide-se numa rica rede vascular da qual emergem arteríolas pré-capilares que se ramificam em capilares, os quais se dirigem em profundidade penetrando a rampa timpânica da cóclea ao nível da espira basal. Importou neste estudo verificar quais as semelhanças em termos de calibre de estruturas análogas, na parede interna e na parede externa da cóclea, com particular incidência na rede capilar. Do estudo estatístico realizado com testes paramétricos de Tamahane e não paramétricos de Mann-Whitney, verifica-se que comparando todas as estruturas consideradas estas têm calibres diferentes, com excepção dos capilares da estria vascular e do ligamento espiral, pertencentes à parede externa da cóclea que têm calibres iguais aos capilares da rede espiral interna e aos capilares da parede interna da cóclea, dependentes das arteríolas da rede espiral interna. As redes capilares dependentes das arteríolas radiárias internas que vascularizam as estruturas sensorioneurais junto á parede interna do modiolo são em tudo semelhantes em termos de calibre às redes capilares da parede externa da cóclea, incluindo os capilares da estria vascular. Esta particularidade traduz num órgão com vascularização de tipo terminal,um mecanismo de controlo do fluxo sanguíneo coclear tão importante na parede interna como na parede externa da cóclea. ------------ ABSTRACT:Current studies on sensorineural hearing loss, imply a growing group of situations in which the lesion is located at the level of the cochlear microvasculature, hence the exact knowledge of normal angiomorfology becomes essential in current state of knowledge. The author has been studying since 1986, the angiomorfology of inner on the experimental model, the guinea pig, using various microvascular techniques being given particular emphasis in this study to the results of the technique of scanning electron microscopy on corrosion casts. The animals used in this study belong to the species cavia porcellus, guinea pig, to be considered in the international scientific community as the best experimental model for the study of the inner ear, the cochlear morphology is very similar to human and therefore a reliable model for experimental surgery and microdissection. This study was performed in 100 guinea pigs of both sexes with average weight of 450g. There shall be a brief description of embryology, anatomy and cochlear physiology in the light of developmental biology, regarding also the spatial location of the cochlea and the determinism of morphogenetic fields in their development and function. The cochlear transduction mechanism converts the sound wave in stimuli sound and so afferent auditory nerve fibres and deafness are closely related to the cochlear microvasculature. Cochlear ischemia is accompanied by immediate hearing loss. The different type of cochlear injury that leads to sensorineural deafness is well studied in presbycusis where an objective link with the audiometric pattern as been established. The sensory type of deafness, is closely related to the degeneracy of the organ of Corti and damage to the outer hair cells at the basal turn of the cochlea. Keeping in mind cochlear tonotopy with location of high frequency sounds at the level of the base of the cochlea, it explains the audiometric pattern with loss in high frequencies. The neural type of deafness, is characterized by neuronal loss with loss of descendant important neuronal afferents, with audiometric translation on a gradually curve with important loss of auditory discrimination. The metabolic type of deafness results in atrophy of the vascular stria, with consequent change in the potential of the endolymph by decreasing the vascular stria cells and changes in K + recycling mechanism. There is also a change in the morphology of the spiral ligament and the audiometric patern as a flattened curve with loss at all frequencies. Bearing in mind cochlear tonotopy and being characterized all types of sensorineural deafness, we may inquire to what extent the cochlear microvasculature, considering not only the cochlea as a whole but different regions of the inner wall and the outer wall of the cochlea, contributes to deafness. We analysed the entire cochlear morphology on scanning electron microscopy with particular emphasis on bone and membranous cochlea. The inner wall of the cochlea and intramodiolar structures such as the spiral ganglion, the morphology of its cell bodies and their axons are analyzed. The morphology of Corti’s organ is described in detail, with description and large detail of the inner and outer hair cells. Is then presented the study of the microvasculature itself. The spiral modiolar artery is observed with the diaphanization technique and the technique of scanning electron microscopy on corrosion vascular casts. After emergence of collateral branches of the greatest importance, the radiating internal and external arterioles, the modiolar artery gives rise to its terminal branches, the arterioles of the cochear apex. Arterial vasa vasorum and vasa nervorum are displayed with a great detail, which was not yet described in such detail in previous microvascular studies. The arterial radiating arterioles originate in the flank of the spiral modiolar artery in number of ten to twelve in each loop, and they vascularize through their branches the inner wall cochlear sensorineural structures located in the modiolus as the spiral ganglion and structures near the organ of Corti. Their caliber is above 20 μm on the basal turn and in the second loop it decreases to values between 12 and 20 μm, decreasing progressively to the apex of the cochlea.They arise near the modiolus or on their way in the spiral lamina forming vascular loops, and divide without presenting vascular constrictions in their divisions, originating new vascular loops of lower caliber. Internal ratiating arterioles originate as collateral branches several groups of smaller caliber arterioles, which vascularize distinct regions of the inner wall of the cochlea namely, the arterioles of the spiral ganglion, the internal spiral network, the arterioles of origin of the glomeruli of Schwalbe and the arterioles of the basilar membrane. The glomeruli of Schwalbe play an important functional role as relay-stations, in hemodynamic terms, to control the cochlear microvasculature. External radiating arterioles have their origin in the spiral modiolar artery, they are directed towards the outer wall of the cochlea and run through the roof of the scala vestibuli. Above the insertion of Reissner’s membrane on the external wall the external radiating arterioles originate the spiral ligament arterioles, which vascularize the spiral ligament, they divide into several arteriolar branches of smaller caliber, along the convexity of the outer edge of the spiral ligament. The connective tissue of the spiral ligament forms a mesh with supporting function of the highly specialized epithelium, where pericytes were identifiable. Next to its base there is the microvascular network of stria vascularis. The adstriated vascular network which is divided into a capillary network, the capillary network of stria vascularis. The stria vascularis, the only vascularized epithelium of the human body, plays an important role, forming an haemato-labyrintine barrier to assure labyrinthine endocochlear potential and transport of ions, essential for the mechanism of transduction of external hair cells. The cochlear basal turn has a special feature on its external wall, the region of the windows, the round windows giving access to scala tympani and the oval window thatleads into scala vestibuli, and so it is metabolic demanding. For their role in cochlear tonotopy the sensorineural structures and those of the external wall of the cochlea, are particularly vulnerable to hypoxia. Although the complementarity of all the techniques was important for three- -dimensional reconstruction of the microvasculature of the cochlea, the scanning electron microscopy technique, especially when we used the system Semafore was fundamental to perform precise morphometric mesures regarding all vascular structures.Regarding the capillaries of the inner and outer wall of the cochlea networks this technique allowed their characterization in morphometric terms. To conclude the capillaries of the inner wall and of the external wall of the cochlea have similar size. So although located at different cochlear regions, with a different functional role, in cochlear physiology these networks consist of capillaries of similar caliber. It seems to translate a cochlear blood flow control mechanism that is so important in the inner wall as in and the external wall of the cochlea to provide for in inner ear homeosthasia.
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Potential risks of a secondary formation of polychlorinated dibenzodioxins/furans (PCDD/Fs) were assessed for two cordierite-based, wall-through diesel particulate filters (DPFs) for which soot combustion was either catalyzed with an iron- or a copper-based fuel additive. A heavy duty diesel engine was used as test platform, applying the eight-stage ISO 8178/4 C1 cycle. DPF applications neither affected the engine performance, nor did they increase NO, NO2, CO, and CO2 emissions. The latter is a metric for fuel consumption. THC emissions decreased by about 40% when deploying DPFs. PCDD/F emissions, with a focus on tetra- to octachlorinated congeners, were compared under standard and worst case conditions (enhanced chlorine uptake). The iron-catalyzed DPF neither increased PCDD/F emissions, nor did it change the congener pattern, even when traces of chlorine became available. In case of copper, PCDD/F emissions increased by up to 3 orders of magnitude from 22 to 200 to 12 700 pg I-TEQ/L with fuels of < 2, 14, and 110 microg/g chlorine, respectively. Mainly lower chlorinated DD/Fs were formed. Based on these substantial effects on PCDD/F emissions, the copper-catalyzed DPF system was not approved for workplace applications, whereas the iron system fulfilled all the specifications of the Swiss procedures for DPF approval (VERT).
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The Miocene PX1 gabbro-pyroxenite pluton, Fuerteventura, Canary Islands, is a 3.5 x 5.5 km shallow-level intrusion (0.15-0.2 GPa and 1100-1120 degrees C), interpreted as the feeder-zone to an ocean-island volcano. It displays a vertical magmatic banding expressed in five 50 to 100 metre-wide NNE-SSW trending alkaline gabbro sequences alternating with pyroxenites. This emplacement geometry was controlled by brittle to ductile shear zones, generated by a regional E-W extensional tectonic setting that affected Fuerteventura during the Miocene. At a smaller scale, the PX1 gabbro and pyroxenite bands consist of metre-thick differentiation units, which suggest emplacement by periodic injection of magma pulses as vertical dykes that amalgamated, similarly to a sub-volcanic sheeted dyke complex. Individual dykes underwent internal differentiation following a solidification front parallel to the dyke edges. This solidification front may have been favoured by a significant lateral/horizontal thermal gradient, expressed by the vertical banding in the gabbros, the fractionation asymmetry within individual dykes and the migmatisation of the wall rocks. Pyroxenitic layers result from the fractionation and accumulation of clinopyroxene +/- olivine +/- plagioclase crystals from a mildly alkaline basaltic liquid. They are interpreted as truncated differentiation sequences, from which residual melts were extracted at various stages of their chemical evolution by subsequent dyke intrusions, either next to or within the crystallising unit. Compaction and squeezing of the crystal mush is ascribed to the incoming and inflating magma pulses. The expelled interstitial liquid was likely collected and erupted along with the magma flowing through the newly injected dykes. Clinopyroxene mineral orientation - as evidenced by EBSD and micro X-ray tomography investigations - displays a marked pure-shear component, supporting the interpretation of the role of compaction in the generation of the pyroxenites. Conversely, gabbro sequences underwent minor melt extraction and are believed to represent crystallised coalesced magma batches emplaced at lower rates at the end of eruptive cycles. Clinopyroxene orientations in gabbros record a simple shear component suggesting syn-magmatic deformation parallel to observed NNE-SSW trending shear zones induced by the regional tensional stress field. This emplacement model implies a crystallisation time of 1 to 5 years for individual dykes, consistent with PX1 emplacement over less than 0.5 My. A minimum amount of approximately 150 km(3) of magma is needed to generate the pluton, part of it having been erupted through the Central Volcanic Centre of Fuerteventura. If the regional extensional tectonic regime controls the PX1 feeder-zone initiation and overall geometry, rates and volumes of magma depend on other, source-related factors. High injection rates are likely to induce intrusion growth rates larger than could be accommodated by the regional extension. In this case, dyke intrusion by propagation of a weak tip, combined with the inability of magma to circulate through previously emplaced and crystallised dykes could result in an increase of non-lithostatic pressure on previously emplaced mushy dyke walls; thus generating strong pure-shear compaction within the pluton feeder-zone and interstitial melt expulsion. These compaction-dominated processes are recorded by the cumulitic pyroxenite bands. (C) 2010 Elsevier B.V. All rights reserved.
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Diplomityön tavoitteena on järkeistää terästehtaan laskujen käsittelyä sekä parantaa ostotoiminnan kustannustietämystä. Työssä keskitytään kolmeen case-tapaukseen: ostolaskuja eniten lähettävään yritykseen ja kahteen romutoimittajaan, joiden laskukäsittely vie ajallisesti pitkään. Ostotoimintoja tarkastellaan prosessina tilauksesta ostolaskukäsittelyyn. Työssä on haastateltu kunnossapidon työnjohtoa ja laskunkäsittelijöitä, joiden perusteella on kartoitettu nykytila ja listattu parannusehdotukset. Työn lopputuloksena ehdotetaan toimintatapojen muutosta. Tavoitteena on saada laskut paremmin kirjattua järjestelmään ja kohdennettua oikeille tilauksille, jolloin kustannusinformaatio parantuu. Sähköisellä laskutusohjelmiston käyttöönotolla voitaisiin järkeistää sisäistä laskunkiertoa ja arkistointia.