358 research outputs found

    Exploring the impact of technological competence development on speed and NPD program performance

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    With growing levels of competition across industries, technological competence is increasingly viewed as crucial for businesses to maintain their long-term competitive advantage. Although there are many theoretical arguments about how firms' competences can yield competitive advantage and performance improvement, we have a limited understanding of where the capabilities originate in the context of NPD or what kind of product portfolios, internal climate and strategic alignment are required to build them. Moreover, empirical evidence for technological competence development is limited and comes primarily from case studies, anecdotal evidence, and management impressions. Accordingly, this research addresses these gaps by presenting and testing a conceptual model of technological competence development in NPD. This study makes advances in applying a dynamic capability approach to technological competence development in NPD, and investigates the impact of innovative climate, technological alignment, and project portfolio management on technological competence development as well as NPD speed. Moreover, the factors that might influence NPD program performance are also investigated. The analysis, based on data collected from 164 firms, shows that a firm's innovative climate, technological alignment and portfolio management are positively associated with technological competence development. While technological alignment was found to be negatively related to NPD speed, portfolio management and technological competence development were found to have positive effects on speed. However, innovative climate had no significant impact on speed. Moreover, technological competence development and portfolio management were found to be positively related to NPD program performance. Finally, the authors found no support for the relationship between speed and NPD program performance

    Evaluation of metabolic profiles of Saanen goats in the transition period

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    ΔΕΝ ΔΙΑ΀ΙΘΕ΀ΑΙ ΠΕΡΙΛΗιΗHealthy Saanen goats (n=30) in periparturient period were used in the present study. Blood samples were collected 21, 14 and 7 days before parturition, at the time of birth and postpartum days 7, 14 and 21. Non-esterifiedfatty acids (NEFA), betahydroxy butyric acid (BHBA), Total protein (TP), albumin (ALB), blood urea nitrogen (BUN), creatinine (CREA) aspartate amino transferase (AST), gamma glutamyl transferase (GGT), sorbitol dehydrogenase (SDH), glucose (GLU), cholesterol (CHOL), triglyceride (TG), calcium (Ca), phosphorus (P), and magnesium (Mg) levels were evaluated. During the study period, NEFA, SDH, CREA levels increased and CHOL and TG levels decreased at time of parturition. When the changes of parameters in prepartum and postpartum period were compared, the concentrations of NEFA, CHOL, GLU, TG, Ca were higher (p <0.001) in prepartum period;however BHBA, Mg, ALB, GGT, AST, TP, P, BUN, SDH and CREA concentrations were detected to be higher (p <0.001) in postpartum period. Metabolic Profile Test based on biochemical parameters evaluated in our study would be beneficial for diagnosis, prevention and control of diseases such as pregnancy toxemia, hypocalcemia, infertility in goats

    A novel application of queueing theory on the Caulerpenyne secreted by invasive Caulerpa taxifolia (Vahl) C.Agardh (Ulvophyceae, Caulerpales): a preliminary study

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    Aquarium originated marine green alga Caulerpa taxifolia was introduced into the Mediterranean Sea accidentally in 1984. This invasion has been negatively affecting the sub-littoral ecosystem of the Mediterranean. One of the important reasons for its success in the Mediterranean is its secondary toxic metabolite called caulerpenyne (CPN). Furthermore, CPN has anti-proliferative and apoptotic activities, therefore, CPN can be considered as a potential native source in cancer therapy. For that reason, modeling this metabolite might be of importance. Increase and decrease of the CPN level before reaching the critical level can be expressed by means of a queueing system in which the number of ‘customers' increases and decreases. In fact, production of CPN shows fluctuations for many environmental reasons, which allow us to apply queueing theory. In the present study, the expected time to reach the maximum caulerpenyne level was analyzed and evaluated using queueing theory

    Human System Engineering Applications from Distracted Driving Simulations

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    Most of the studies to explore the impact of distracted driving have been descriptive in nature; i.e. the research is conducted in naturalistic settings to evaluate the performance of the driver with and without distracters. However simulation models can also be used that predict the workload for driving tasks. Using concepts from process modeling, baseline models of driving tasks can be created for different driving sequences that include the associated fine motor, visual and cognitive human resources. These models can then be used to evaluate incidents of workload overload caused by different distracters, from both the internal and external vehicle environment. Identifying specific overloaded resources can lead to mitigation strategies to reduce workload and minimize distracted driving. Lessons learned from distracted driving research can then be applied to evaluation other types of manual, visual, and cognitive intensive tasks. Identifying combinations of tasks that contribute to peak workload of operators, and then simulating the impact of multi-tasking using personal devices (i.e. cell phones) can lead to management insights for other types of work environments. Additionally, iterative modeling can also include the impact of sensors and alerts, as well as enhanced workstation displays. Individual component overload can help understand causes for performance detriments during different task sequences, and the impact of additional types of technologies and activities. Using the simulation analysis, the impact on overall workload, identification of peak workload occurrences, and specific overloaded resources can lead to mitigation strategies to reduce workload and improve operator performance

    Employee-Task Assignments for Organization Modeling: A Review of Models and Applications

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    In this study, we present a review of task assignment problems in organizations, an area that has become more important as tasks become more complex and personnel skills become more specialized. The challenge is to design task assignments that meet all requirements and result in the best organizational performance. The consequences of poor design include failed tasks, reduced efficiency, and inability to meet deadlines. Moreover, inequity of workload between employees can cause lack of job satisfaction, loss of motivation and also boredom. In general, work processes in organizations consist of different tasks, which require different expertise. Personnel usually have various degrees of qualifications and their performance may vary for different tasks. The outcome of the work process depends heavily on which tasks are assigned to which personnel. Performance of an organization can be increased by assigning the tasks to the most qualified available personnel. However, it could result in overloading some personnel while the others remain under-loaded. So, the even distribution of the workload between them also needs to be taken into consideration. In addition, it helps to increase organization\u27s productivity by distributing personnel\u27s knowledge, time, and attention more extensively. We review task-employee assignment problems in organization modeling with the computational models that have been reported in the literature with their applications. Human factors engineering, in terms of workload in organizational modeling is included as the work process performance is heavily dependent on the human (personnel). Based on the initial findings, we propose to investigate an improved workload model that allows the use of optimization of select constraints, such as balancing workload among team members. While current workload models allow the evaluation of workload among team members interacting in a work process, it is up to the analyst to suggest improvements. By providing an optimized solution, we present the Engineering Manager, that can then be adjusted to meet practical criteria

    Two Electrons in a Quantum Dot: A Unified Approach

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    Low-lying energy levels of two interacting electrons confined in a two-dimensional parabolic quantum dot in the presence of an external magnetic field have been revised within the frame of a novel model. The present formalism, which gives closed algebraic solutions for the specific values of magnetic field and spatial confinement length, enables us to see explicitly individual effects of the electron correlation.Comment: 14 page

    Does shear wave ultrasound independently predict axillary lymph node metastasis in women with invasive breast cancer?

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    Shear wave elastography (SWE) shows promise as an adjunct to greyscale ultrasound examination in assessing breast masses. In breast cancer, higher lesion stiffness on SWE has been shown to be associated with features of poor prognosis. The purpose of this study was to assess whether lesion stiffness at SWE is an independent predictor of lymph node involvement. Patients with invasive breast cancer treated by primary surgery, who had undergone SWE examination were eligible. Data were retrospectively analysed from 396 consecutive patients. The mean stiffness values were obtained using the Aixplorer(Ÿ) ultrasound machine from SuperSonic Imagine Ltd. Measurements were taken from a region of interest positioned over the stiffest part of the abnormality. The average of the mean stiffness value obtained from each of two orthogonal image planes was used for analysis. Associations between lymph node involvement and mean lesion stiffness, invasive cancer size, histologic grade, tumour type, ER expression, HER-2 status and vascular invasion were assessed using univariate and multivariate logistic regression. At univariate analysis, invasive size, histologic grade, HER-2 status, vascular invasion, tumour type and mean stiffness were significantly associated with nodal involvement. Nodal involvement rates ranged from 7 % for tumours with mean stiffness <50 kPa to 41 % for tumours with a mean stiffness of >150 kPa. At multivariate analysis, invasive size, tumour type, vascular invasion, and mean stiffness maintained independent significance. Mean stiffness at SWE is an independent predictor of lymph node metastasis and thus can confer prognostic information additional to that provided by conventional preoperative tumour assessment and staging

    Catalytic partial oxidation of methane on platinum investigated by spatial reactor profiles, spatially resolved spectroscopy, and microkinetic modeling

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    Spatially resolved profile measurements, Raman spectroscopy, electron microscopy, and microkinetic modeling have been used to study the catalytic partial oxidation of methane on Pt. The measured species profiles through Pt coated foam catalysts exhibit a two-zone structure: an abrupt change in reaction rates separates the fast exothermic oxidation chemistry at the entrance of the reactor from the slow endothermic reforming chemistry. Spatially resolved Raman spectroscopy and electron microscopy confirm that the position of the mechanistic change could be correlated with Pt transportation and formation of carbonaceous deposits blocking the majority of active Pt sites in the reforming zone. The species profiles were simulated using a pseudo-2D heterogeneous model, which includes heat and mass transport limitations, and two state-of-the-art chemical kinetic mechanisms. Although both mechanisms are in quantitative agreement with the oxygen profiles, the two mechanisms differ substantially in their predictions of the branching ratio between partial and complete oxidation, as well as surface site coverages. The experimentally observed change in reaction rates is attributed to carbon formation, which the mechanisms are unable to reproduce, since they do not include carbon–carbon coupling reactions
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