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51.
The purpose of this paper is to provide an enabler-based approach for a supervised self-assessment of operations excellence (OsE). Based on the latest approaches of excellence in operations from the literature as well as on the philosophy of the EFQM model, an OsE working definition was developed. In contrast to operational excellence (OE), which deals exclusively with the optimization of result driven processes, OsE promotes the enhancement of operation-specific enablers and linked results. The evaluation of crucial cause–effect relationships of relevant enabler and result criteria supports the determination of a company’s capability to achieve sustainability and excellence in terms of its operations. To foster a methodical integration of OsE in organizations, a phase model for a systematic assessment process was designed and verified with 24 companies in the Austrian machinery and metalware industries. 相似文献
52.
Future systems will be too complex to design and implement explicitly. Instead, we will have to learn to engineer complex behaviours indirectly: through the discovery and application of local rules of behaviour, applied to simple process components, from which desired behaviours predictably emerge through dynamic interactions between massive numbers of instances. This paper describes a process-oriented architecture for fine-grained concurrent systems that enables experiments with such indirect engineering. Examples are presented showing the differing complex behaviours that can arise from minor (non-linear) adjustments to low-level parameters, the difficulties in suppressing the emergence of unwanted (bad) behaviour, the unexpected relationships between apparently unrelated physical phenomena (shown up by their separate emergence from the same primordial process swamp) and the ability to explore and engineer completely new physics (such as force fields) by their emergence from low-level process interactions whose mechanisms can only be imagined, but not built, at the current time. 相似文献
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ABSTRACTWind turbine control is an important task to make the electricity generation secure in terms of energy demand and machine safety. It also yields to control the desired power level and optimized energy because of the assignment of turbine speed. The contactless piezoelectric wind energy harvester (CPWEH) used in this study has three piezoelectric layers located around the shaft with 120 degrees apart and they are buckled by the magnetic force without any physical contact. The superiority of this device is to generate energy for low wind speeds such as 1.5 m/s. However, for high speeds, high total harmonic distortions (THDs) govern the waveforms, thus controlling the turbine speed becomes necessary for optimizing the output power. Encouraged by this, a small low inertia dc generator is coupled with the wind turbine, and the generator terminals are connected to a resistor through a power switch to generate a braking torque that opposes to wind speed direction. By controlling the switch properly, turbine speed is ensured to remain within a certain band, which accordingly prevents the turbine from rotating very fast at damaging wind speeds. Several experiments are performed on the developed CPWEH with/without the presented control scheme which prove the existence of promising performance of our proposal. 相似文献
56.
Mass detection is a very important process for breast cancer diagnosis and computer aided systems. It can be very complex when the mass is small or invisible because of dense breast tissue. Therefore, the extraction of suspicious mass region can be very challenging. This paper proposes a novel segmentation algorithm to identify mass candidate regions in mammograms. The proposed system includes three parts: breast region and pectoral muscle segmentation, image enhancement and suspicious mass regions identification. The first two parts have been examined in previous studies. In this study, we focused on suspicious mass regions identification using a combination of Havrda & Charvat entropy method and Otsu's N thresholding method. An open access Mammographic Image Analysis Society (MIAS) database, which contains 59 masses, was used for the study. The proposed system obtained a 93% sensitivity rate for suspicious mass regions identification in 56 abnormal and 40 normal images. 相似文献
57.
In spite of its great importance for the dry classification of fine powders, the processes in deflector wheel classifiers are to a large extent unknown. Therefore, in the present work a commercial available classifier was modified to gain an optical access to the deflector wheel. For the first time, the obtained photographs enable an observation of the gas flow and the particle motion between the blades of the deflector wheel. Especially the importance of particle‐particle‐ and particle‐blade‐collisions could be shown. 相似文献
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Wax Ester Rich Oil From The Marine Crustacean,Calanus finmarchicus,is a Bioavailable Source of EPA and DHA for Human Consumption 下载免费PDF全文
Chad M. Cook Terje S. Larsen Linda D. Derrig Kathleen M. Kelly Kurt S. Tande 《Lipids》2016,51(10):1137-1144
Oil from the marine copepod, Calanus finmarchicus, which contains >86 % of fatty acids present as wax esters, is a novel source of n‐3 fatty acids for human consumption. In a randomized, two‐period crossover study, 18 healthy adults consumed 8 capsules providing 4 g of Calanus® Oil supplying a total of 260 mg EPA and 156 mg DHA primarily as wax esters, or 1 capsule of Lovaza® providing 465 mg EPA and 375 mg DHA as ethyl esters, each with an EPA‐ and DHA‐free breakfast. Plasma EPA and DHA were measured over a 72 h period (t = 1, 2, 4, 6, 8, 10, 12, 24, 48, and 72 h). The positive incremental area under the curve over the 72 h test period (iAUC0‐72 h) for both EPA and DHA was significantly different from zero (p < 0.0001) in both test conditions, with similar findings for the iAUC0–24 h and iAUC0–48 h, indicating the fatty acids were absorbed. There was no difference in the plasma iAUC0–72 h for EPA + DHA, or DHA individually, in response to Calanus Oil vs the ethyl ester condition; however, the iAUC0–48 h and iAUC0–72 h for plasma EPA in response to Calanus Oil were both significantly increased relative to the ethyl ester condition (iAUC0–48 h: 381 ± 31 vs 259 ± 39 μg*h/mL, p = 0.026; iAUC0‐72 h: 514 ± 47 vs 313 ± 49 μg*h/mL, p = 0.009). These data demonstrate a novel wax ester rich marine oil is a suitable alternative source of EPA and DHA for human consumption. 相似文献
60.
Regio‐ and Enantioselective Sequential Dehalogenation of rac‐1,3‐Dibromobutane by Haloalkane Dehalogenase LinB 下载免费PDF全文
Johannes Gross Prof. Zbyněk Prokop Prof. Dick Janssen Prof. Kurt Faber Dr. Mélanie Hall 《Chembiochem : a European journal of chemical biology》2016,17(15):1437-1441
The hydrolytic dehalogenation of rac‐1,3‐dibromobutane catalyzed by the haloalkane dehalogenase LinB from Sphingobium japonicum UT26 proceeds in a sequential fashion: initial formation of intermediate haloalcohols followed by a second hydrolytic step to produce the final diol. Detailed investigation of the course of the reaction revealed favored nucleophilic displacement of the sec‐halogen in the first hydrolytic event with pronounced R enantioselectivity. The second hydrolysis step proceeded with a regioselectivity switch at the primary position, with preference for the S enantiomer. Because of complex competition between all eight possible reactions, intermediate haloalcohols formed with moderate to good ee ((S)‐4‐bromobutan‐2‐ol: up to 87 %). Similarly, (S)‐butane‐1,3‐diol was formed at a maximum ee of 35 % before full hydrolysis furnished the racemic diol product. 相似文献