Browsing by Subject "PERFORMANCE"

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  • Kumar, Prashant; Sharma, Arun; Salo, Jari (2019)
    Key account management (KAM) has played an important role in business, and this study reviews key account management research using bibliometric techniques. This review includes 373 KAM relevant articles published in 68 journals between 1979 and 2016. In our analysis, we extend the discussion on KAM literature by highlighting areas such as the roles of technology and conflict as well as relationship planning and implementation. We discuss the value of co-creation, inter-organizational design elements, and dyad-level performance measures. We examine five distinctive time-periods and find that KAM relevant literature has progressed 1) from selling and relationship-building approaches to key network management, 2) from network innovation to governance, 3) from network-level performance to co-creation of business solutions and values, 4) from product and service performance to incorporating sustainability. Finally, we present the fifth transition based on a network-view of KAM and identify future research aimed at integrating areas such as network-based orientation, applications of organizational theories, organizational innovativeness, network competence for optimal structure and processes, network-based KAM teams, value-sharing mechanisms, co-created value measurement, and value sustenance within networks. We identify areas of future research and expect the adoption and application of key account management concepts to grow across multiple disciplinary fields.
  • Sanwald, Corinna; Robciuc, Alexandra; Ruokonen, Suvi-Katriina; Wiedmer, Susanne K.; Lammerhofer, Michael (2019)
    This work presents the development and validation of a quantitative HILIC UHPLC-ESI-QTOF-MS/MS method for amino acids combined with untargeted metabolic profiling of human corneal epithelial (HCE) cells after treatment with ionic liquids. The work included a preliminary metabotoxicity screening of 14 different ionic liquids, of which 9 carefully selected ionic liquids were chosen for a metabolomics study. This study is focused on the correlation between the toxicity of the ionic liquids and their metabolic profiles. The method development included the comparison of different MS/MS acquisition modes. A sequential window acquisition of all theoretical fragment ion mass spectra (SWATH) method with variable Q1 window widths and narrow Q1 target windows of 5 Da for most of the amino acids was selected as the optimal acquisition mode. Due to the absence of a true blank matrix, C-13,N-15-isotopically labelled amino acids were utilized as surrogate calibrants, instead of proteinogenic amino acids. Partial least squares (PLS) analysis of the median effective concentrations (EC50) of 9 selected ionic liquids showed a correlation with their metabolic profile measured by the untargeted screening.
  • Lalarukh, Irfana; Al-Dhumri, Sami A.; Al-Ani, Laith Khalil Tawfeeq; Hussain, Rashid; Al Mutairi, Khalid Awadh; Mansoora, Nida; Amjad, Syeda Fasiha; Abbas, Mohamed H. H.; Abdelhafez, Ahmed A.; Poczai, Peter; Meena, Khem Raj; Galal, Tarek M. M.; Galal, Tarek M. (2022)
    Less nutrient availability and drought stress are some serious concerns of agriculture. Both biotic and abiotic stress factors have the potential to limit crop productivity. However, several organic extracts obtained from moringa leaves may induce immunity in plants under nutritional and drought stress for increasing their survival. Additionally, some rhizobacterial strains have the ability to enhance root growth for better nutrient and water uptake in stress conditions. To cover the knowledge gap on the interactive effects of beneficial rhizobacteria and moringa leaf extracts (MLEs), this study was conducted. The aim of this experimental study was to investigate the effectiveness of sole and combined use of rhizobacteria and MLEs against nutritional and drought stress in wheat. Nitrogen-fixing bacteria Pseudomonas aeruginosa (Pa) (10(8) CFU ml(-1)) was inoculated to wheat plants with and without foliar-applied MLEs at two different concentrations (MLE 1 = 1:15 v/v and MLE 2 = 1:30 v/v) twice at 25 and 35 days after seed sowing (50 ml per plant) after the establishment of drought stress. Results revealed that Pa + MLE 2 significantly increased fresh weight (FW), dry weight (DW), lengths of roots and shoot and photosynthetic contents of wheat. A significant enhancement in total soluble sugars, total soluble proteins, calcium, potassium, phosphate, and nitrate contents validated the efficacious effect of Pa + MLE 2 over control-treated plants. Significant decrease in sodium, proline, glycine betaine, electrolyte leakage, malondialdehyde, hydrogen peroxide, superoxide dismutase (SOD), and peroxide (POD) concentrations in wheat cultivated under drought stress conditions also represents the imperative role of Pa + MLE 2 over control. In conclusion, Pa + MLE 2 can alleviate nutritional stress and drought effects in wheat. More research in this field is required to proclaim Pa + MLE 2 as the most effective amendment against drought stress in distinct agroecological zones, different soil types, and contrasting wheat cultivars worldwide.
  • Funderud, Tonje; Mononen, Riikka; Radišić , Jelena; Laine, Anu (2019)
    The study aimed to investigate variations in addition and subtraction fluency by observing grade three students in Norway (n = 253, M-age = 8.38 y.) and Finland (n = 209, M-age = 9.35 y.) while controlling for their age and non-verbal reasoning. Gender differences were also examined. The focus of the study was on the performance of the low-achieving (LA) students in comparison to the typically achieving (TA) group, not neglecting differences in how early educational support was organised across the two countries. Two-minute speed tests in both addition and subtraction within the 1-20 number range were used to assess fluency. The Finnish students outperformed students in the Norwegian sample both in addition and subtraction fluency. There were more Norwegian students in the LA group (i.e. performance at or below the 25th percentile) in both addition (37.9% vs. 20.1%) and subtraction (39.1% vs. 15.8%). In comparison to the TA students, the LA students made more errors and skipped over more arithmetic tasks in an attempt to solve them. Observed differences are discussed in relation to both country characteristics concerning early mathematics education and early educational support.
  • Minviel, Jean Joseph; Sipiläinen, Timo (2021)
    This article introduces a dynamic stochastic frontier analysis (SFA) framework with unobserved heterogeneity, persistent and transient inefficiency effects, based on recent advances in the SFA literature. The newly developed dynamic frontier model is applied on a sample of French crop-livestock farms. The estimates provide useful insights for the estimation of the technical efficiency scores as well as for the analysis of the associations of contextual drivers, such as public subsidies and indebtedness, with technical efficiency.
  • Greiff, Samuel; Wuestenberg, Sascha; Goetz, Thomas; Vainikainen, Mari-Pauliina; Hautamäki, Jarkko; Bornstein, March H. (2015)
    Scientists have studied the development of the human mind for decades and have accumulated an impressive number of empirical studies that have provided ample support for the notion that early cognitive performance during infancy and childhood is an important predictor of later cognitive performance during adulthood. As children move from childhood into adolescence, their mental development increasingly involves higher-order cognitive skills that are crucial for successful planning, decision-making, and problem solving skills. However, few studies have employed higher-order thinking skills such as complex problem solving (CPS) as developmental outcomes in adolescents. To fill this gap, we tested a longitudinal developmental model in a sample of 2,021 Finnish sixth grade students (M = 12.41 years, SD = 0.52; 1,041 female, 978 male, 2 missing sex). We assessed working memory (WM) and fluid reasoning (FR) at age 12 as predictors of two CPS dimensions: knowledge acquisition and knowledge application. We further assessed students' CPS performance 3 years later as a developmental outcome (N = 1696; M = 15.22 years, SD = 0.43; 867 female, 829 male). Missing data partly occurred due to dropout and technical problems during the first days of testing and varied across indicators and time with a mean of 27.2%. Results revealed that FR was a strong predictor of both CPS dimensions, whereas WM exhibited only a small influence on one of the two CPS dimensions. These results provide strong support for the view that CPS involves FR and, to a lesser extent, WM in childhood and from there evolves into an increasingly complex structure of higher-order cognitive skills in adolescence.
  • Jousi, Mikko O.; Erkkilä, Jukka; Varjonen, Mari; Soiva, Martti; Hukkinen, Katja; Sequeiros, Roberto Blanco (2019)
    Background Digital breast tomosynthesis (DBT) is gaining popularity in breast imaging. There are several different technical approaches for conducting DBT imaging. Purpose To determine optimal imaging parameters, test patient friendliness, evaluate the initial diagnostic performance, and describe diagnostic advances possible with the new Continuous Sync-and-Shoot method. Material and Methods Thirty-six surgical breast specimens were imaged with digital mammography (DM) and a prototype of a DBT system (Planmed Oy, Helsinki, Finland). We tested the patient friendliness of the sync-and-shoot movement without radiation exposure in eight volunteers. Different imaging parameters were tested with 20 specimens to identify the optimal combination: angular range 30 degrees, 40 degrees, and 60 degrees; pixel binning; Rhodium (Rh) and Silver (Ag) filtrations; and different kV and mAs values. Two breast radiologists evaluated 16 DM and DBT image pairs and rated six different image properties. Imaging modalities were compared with paired t-test. Results The Continuous Sync-and-Shoot method produced diagnostically valid images. Five out of eight volunteers felt no/minimal discomfort, three experienced mild discomfort from the tilting movement of the detector, with the motion being barely recognized. The combination of 30 degrees, Ag filtering, and 2 x 2 pixel binning produced the best image quality at an acceptable dose level. DBT was significantly better in all six evaluated properties (P <0.05). Mean Dose(DBT)/Dose(DM) ratio was 1.22 (SD = 0.42). Conclusion The evaluated imaging method is feasible for imaging and analysing surgical breast specimens and DBT is significantly better than DM in image evaluation.
  • the OBSERVANT Research Group; Biancari, F; Rosato, S; Costa, G; Barbanti, M; D'Errigo, P; Tamburino, C; Cerza, F; Rosano, A; Seccareccia, F (2021)
    OBJECTIVES: We sought to develop and validate a novel risk assessment tool for the prediction of 30-day mortality after surgical aortic valve replacement incorporating a patient's frailty. METHODS: Overall, 4718 patients from the multicentre study OBSERVANT was divided into derivation (n=3539) and validation (n=1179) cohorts. A stepwise logistic regression procedure and a criterion based on Akaike information criteria index were used to select variables associated with 30-day mortality. The performance of the regression model was compared with that of European System for Cardiac Operative Risk Evaluation (EuroSCORE) II. RESULTS: At 30 days, 90 (2.54%) and 35 (2.97%) patients died in the development and validation data sets, respectively. Age, chronic obstructive pulmonary disease, concomitant coronary revascularization, frailty stratified according to the Geriatric Status Scale, urgent procedure and estimated glomerular filtration rate were independent predictors of 30-day mortality. The estimated OBS AVR score showed higher discrimination (area under curve 0.76 vs 0.70, P CONCLUSIONS: The OBS AVR risk score showed high discrimination and calibration abilities in predicting 30-day mortality after surgical aortic valve replacement. The addition of a simplified frailty assessment into the model seems to contribute to an improved predictive ability over the EuroSCORE II. The OBS AVR risk score showed a significant association with long-term mortality.
  • Sundell, Veli-Matti; Jousi, Mikko; Hukkinen, Katja; Blanco, Roberto; Mäkelä, Teemu; Kaasalainen, Touko (2019)
    Background: Digital breast tomosynthesis (DBT) is a three-dimensional breast imaging method. DBT vendors employ various approaches in both image acquisition and data processing, which may affect image quality and radiation exposure to patients. Objective: This study aimed to evaluate the performance of five DBT systems: Fujifilm Amulet Innovality (using both a standard mode and high-resolution mode), GE Senographe Essential, Hologic Selenia Dimensions, Planmed Clarity 3D, and Siemens Mammomat Inspiration. Materials and methods: The performance of each device and imaging technique was evaluated and compared by phantom measurements performed with four quality assurance phantoms. Technical image quality assessments consisted of measuring artefact extent, in-plane resolution, relative noise power spectrum, and geometric accuracy. Results: Artefact spreading varied remarkably between the devices, and the full width at half maximum values of artefact spread functions varied from 3.5 mm to 10.7 mm. Noticeable in-plane resolution anisotropy, determined using modulation transfer function (MTF) analysis, was typically observed between tube travel direction and chest wall-nipple direction. The MTF50 varied from 1.1 mm(-1) to 1.6 mm(-1) and from 1.5 mm(-1) to 4.1 mm(-1) in the tube travel and chest wall-nipple directions, respectively. Moreover, distinctly different noise power spectra were observed between the systems. The geometric accuracy in every system was within 0.5%. Conclusion: Technical image quality assessments with image quality phantoms revealed remarkable differences in artefact spread, in-plane resolution, and noise properties between the DBT systems and imaging methods.
  • Kotze, D. Johan; Kuoppamaki, Kirsi; Niemikapee, Juhamatti; Mesimaki, Marja; Vaurola, Ville; Lehvavirta, Susanna (2020)
    The proliferation of vegetated, or green roofs, warrant a revisit of the terminology used in order to efficiently, and without confusion, convey information among scientists, policy makers and practitioners. A Web of Science and Google Scholar search (from 1996 to 2018) showed a steady increase in green roof articles, reaching close to 300 per year in WOS and ca. 2500 in Google Scholar, with approximately 10-20%, and up to 40 % of all articles using the terms extensive and/or intensive, especially in recent years. We evaluated the use of these terms, including 'green roof, and 'intensive and extensive roof', found that they are used in confusing ways, and provide compelling evidence that there is a need for revising the terminology. Acknowledging that most, if not all, vegetated roofs are multifunctional, we propose a new classification system based on the roof's primary function(s) and vegetation, such as "stormwater meadow roof", "biodiversity meadow roof", "biodiversity forest roof", or even "multifunctional meadow roof". This new terminological sphere is not meant to be rigid, but should be allowed to evolve so that useful combinations survive the scrutiny of academia and practitioners, while less useful ones go extinct. A clear and standardized terminology will serve to avoid confusion, allow for generalizations and aid in the development of this rapidly-expanding field.
  • Wang, Yanhao; Li, Yuchen; Fan, Ju; Ye, Chang; Chai, Mingke (2021)
    Graphs are commonly used for representing complex structures such as social relationships, biological interactions, and knowledge bases. In many scenarios, graphs not only represent topological relationships but also store the attributes that denote the semantics associated with their vertices and edges, known as attributed graphs. Attributed graphs can meet demands for a wide range of applications, and thus a variety of queries on attributed graphs have been proposed. However, these diverse types of attributed graph queries have not been systematically investigated yet. In this paper, we provide an extensive survey of several typical types of attributed graph queries. We propose a taxonomy of attributed graph queries based on query inputs and outputs. We summarize the definitions of queries that fall into each category and present a fine-grained classification of queries within each category by analyzing the semantics and algorithmic motivations behind these queries. Moreover, we discuss the insights of how existing studies address the technical challenges of query processing and outline several promising future research directions.
  • Herodotou, Herodotos; Chen, Yuxing; Lu, Jiaheng (2020)
    Big data processing systems (e.g., Hadoop, Spark, Storm) contain a vast number of configuration parameters controlling parallelism, I/O behavior, memory settings, and compression. Improper parameter settings can cause significant performance degradation and stability issues. However, regular users and even expert administrators grapple with understanding and tuning them to achieve good performance. We investigate existing approaches on parameter tuning for both batch and stream data processing systems and classify them into six categories: rule-based, cost modeling, simulation-based, experiment-driven, machine learning, and adaptive tuning. We summarize the pros and cons of each approach and raise some open research problems for automatic parameter tuning.
  • Schnepel, Susanne; Aunio, Pirjo (2022)
    This systematic review investigates the characteristics of effective mathematics interventions for students with intellectual disabilities (ID) age 5 to 12, focusing on early numeracy, arithmetic, and arithmetical problem solving skills. Twenty studies from 2008-2020 were reviewed: 17 had a single-subject design and three a group-comparison design. The studies included a total of 135 students with ID. Consistent with previous studies, the analysis showed that interventions with systematic and explicit instruction with feedback and the use of manipulatives are effective instructional approaches and strategies for students with ID. This study reveals that effective interventions are well-structured, high intensity learning sequences adapted to the students' achievement level. The intensity of an intervention requires careful consideration of the number of intervention sessions per week and their duration. Further studies should investigate which instructional strategy is most effective for each type of skill and the optimum intensity of interventions.
  • Kaartinen, Harri; Hyyppä, Juha; Vastaranta, Mikko; Kukko, Antero; Jaakkola, Anttoni; Yu, Xiaowei; Pyörälä, Jiri; Liang, Xinlian; Liu, Jingbin; Wang, Yungshen; Kaijaluoto, Risto; Melkas, Timo; Holopainen, Markus; Hyyppä, Hannu (2015)
    A harvester enables detailed roundwood data to be collected during harvesting operations by means of the measurement apparatus integrated into its felling head. These data can be used to improve the efficiency of wood procurement and also replace some of the field measurements, and thus provide both less costly and more detailed ground truth for remote sensing based forest inventories. However, the positional accuracy of harvester-collected tree data is not sufficient currently to match the accuracy per individual trees achieved with remote sensing data. The aim in the present study was to test the accuracy of various instruments utilizing global satellite navigation systems (GNSS) in motion under forest canopies of varying densities to enable us to get an understanding of the current state-of-the-art in GNSS-based positioning under forest canopies. Tests were conducted using several different combinations of GNSS and inertial measurement unit (IMU) mounted on an all-terrain vehicle (ATV) simulating a moving harvester. The positions of 224 trees along the driving route were measured using a total-station and real-time kinematic GPS. These trees were used as reference items. The position of the ATV was obtained using GNSS and IMU with an accuracy of 0.7 m (root mean squared error (RMSE) for 2D positions). For the single-frequency GNSS receivers, the RMSE of real-time 2D GNSS positions was 4.2-9.3 m. Based on these results, it seems that the accuracy of novel single-frequency GNSS devices is not so dependent on forest conditions, whereas the performance of the tested geodetic dual-frequency receiver is very sensitive to the visibility of the satellites. When post-processing can be applied, especially when combined with IMU data, the improvement in the accuracy of the dual-frequency receiver was significant.
  • Holm, Marja; Björn, Piia Maria; Laine, Anu; Korhonen, Johan; Hannula, Markku S. (2020)
    This study investigated mathematics-related achievement emotions among Finnish adolescents (N = 1379) receiving special education support (SEdS) in self-contained and general mathematics classrooms and receiving no mathematics SEdS through multilevel modeling. Mathematics performance, gender, and classroom size were controlled for. Adolescents receiving SEdS in general classrooms reported less enjoyment and pride and more anger, anxiety, shame, hopelessness, and boredom than those receiving SEdS in self-contained classrooms and those receiving no SEdS. In contrast, adolescents receiving SEdS in self-contained classrooms reported more enjoyment and pride and less anger, anxiety, and hopelessness than those receiving no SEdS. Furthermore, adolescents receiving no SEdS reported more anxiety, hopelessness, and boredom in general classrooms when the proportion of classmates receiving SEdS was higher. We discuss the practical implications for developing SEdS in relation to achievement emotions.
  • Laaksonen, Kristina; Helle, Liisa; Parkkonen, Lauri; Kirveskari, Erika; Mäkelä, Jyrki; Mustanoja, Satu; Tatlisumak, Turgut; Kaste, Markku; Forss, Nina (2013)
  • Atashi, Nahid; Tuure, Juuso; Alakukku, Laura; Rahimi, Dariush; Pellikka, Petri; Zaidan, Martha Arbayani; Vuollekoski, Henri; Rasanen, Matti; Kulmala, Markku; Vesala, Timo; Hussein, Tareq (2021)
    Model evaluation against experimental data is an important step towards accurate model predictions and simulations. Here, we evaluated an energy-balance model to predict dew formation occurrence and estimate its amount for East-African arid-climate conditions against 13 months of experimental dew harvesting data in Maktau, Kenya. The model was capable of predicting the dew formation occurrence effectively. However, it overestimated the harvestable dew amount by about a ratio of 1.7. As such, a factor of 0.6 was applied for a long-term period (1979-2018) to investigate the spatial and temporal variation of the dew formation in Kenya. The annual average of dew occurrence in Kenya was similar to 130 days with dew yield > 0.1 L/m(2)/day. The dew formation showed a seasonal cycle with the maximum yield in winter and minimum in summer. Three major dew formation zones were identified after cluster analysis: arid and semi-arid regions; mountain regions; and coastal regions. The average daily and yearly maximum dew yield were 0.05 and 18; 0.9 and 25; and 0.15 and 40 L/m(2)/day; respectively. A precise prediction of dew occurrence and dew yield is very challenging due to inherent limitations in numerical models and meteorological input parameters.
  • Loeblein, Jochen; Lorson, Thomas; Komma, Miriam; Kielholz, Tobias; Windbergs, Maike; Dalton, Paul D.; Luxenhofer, Robert (2021)
    Additive manufacturing or 3D printing as an umbrella term for various materials processing methods has distinct advantages over many other processing methods, including the ability to generate highly complex shapes and designs. However, the performance of any produced part not only depends on the material used and its shape, but is also critically dependent on its surface properties. Important features, such as wetting or fouling, critically depend mainly on the immediate surface energy. To gain control over the surface chemistry post-processing modifications are generally necessary, since it' s not a feature of additive manufacturing. Here, we report on the use of initiator and catalyst-free photografting and photopolymerization for the hydrophilic modification of microfiber scaffolds obtained from hydrophobic medical-grade poly(epsilon-caprolactone) via melt-electrowriting. Contact angle measurements and Raman spectroscopy confirms the formation of a more hydrophilic coating of poly(2-hydroxyethyl methacrylate). Apart from surface modification, we also observe bulk polymerization, which is expected for this method, and currently limits the controllability of this procedure.
  • Lassen, Brian; Geldhof, Peter; Hälli, Outi; Vlaminck, Johnny; Oliviero, Claudio; Orro, Toomas; Heinonen, Mari (2019)
    During their migration through the pig's body, Ascaris suum larvae cause significant damage to the lungs. Little is known about the actual impact of this tissue damage on the occurrence and severity of respiratory problems in industrial pig fattening farms. In this study, we evaluated the link between the serological response to two different A. suum antigen preparations and respiratory or meat inspection outcomes. Two different serological tests were used that measure antibodies against either the A. suum haemoglobin molecule or complete homogenate of the 3rd stage larva that migrate through the lungs. Firstly, serum samples were analysed that were collected from 19 herds in which the cause of acute clinical respiratory symptoms was either Actinobacillus pleuropneumoniae, A. suum, or a miscellaneous cause. This was done to test whether serological results could confirm pathological findings. Secondly, serum samples from 60 herds of finishing pigs with a history of high or low frequency of pleuritis at meat inspection (MI), but without acute respiratory symptoms at the time of sampling, were also submitted for serological evaluation using both tests. Regression models were used to search for potential associations between the proportion of pigs testing seropositive with MI results, in particular pathological changes related to the lungs. The results of both ELISAs were strongly associated (P <0.001) with pigs belonging to a herd where the respiratory problems could be attributed to A. swim by histology, indicating that both tests can be used to diagnose clinical respiratory outbreaks due to A. suum. In the herds without acute clinical respiratory symptoms, a positive association was found between the proportion of pigs testing seropositive and the percentage of livers rejected due to milk spots and with whole carcass condemnations. No association was found between Ascaris serology and lung pathology (pneumonia and pleuritis) registered at MI, however, challenging the likely involvement of Ascaris in the development of these lesions.