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81.
The working principle of the laser-aided direct metal tooling(DMT) process is the use of a laser to selectively clad metallic powder on the substrate material part. A high-powered laser beam is focused on a metal substrate to create a molten weld pool; as the laser passes by the deposit is quickly cooled, leaving behind a thin line of metal clad. The major advantage of the DMT process is its capability of depositing a multitude of materials. Since the material deposition relies only on the feeding of a powder, it is relatively simple to use multiple kinds of materials. In fact, recent research has shown that DMT is capable of manufacturing binary functionally graded materials as well. The study is to develop a software support tool, visual simulation technique, as one of the e-manufacturing capability established for a unique DMT process. 相似文献
82.
Moon Joo Hyun Lee Soyeong Park Jee Min Lee Jungho Kim Daejoong Lee Seong Hyuk 《Journal of Mechanical Science and Technology》2018,32(12):6021-6027
Journal of Mechanical Science and Technology - The present study aims to numerically analyze the cooling characteristics of the air-jet array in designing more efficient air-cooling system. Heat... 相似文献
83.
In C- and Al-free electrical steel, the increase in primary grain size with increasing pre-annealing temperature causes the transition in annealing texture after final annealing from {110} + {100} to {110}. The strip pre-annealed at 1073 K (800 °C) shows a low magnetic induction B8(T) of 1.784 T after final annealing. The strip pre-annealed at 1223 K (950 °C) shows a sharp {110}〈001〉 Goss texture, producing a high magnetic induction B8(T) of 1.914 T comparable to that of the conventional electrical steels. 相似文献
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86.
Seung-Cheol Jee Kwang Min Lee Min Kim Yoo-Jung Lee Soee Kim Joon-Oh Park Jung-Suk Sung 《International journal of molecular sciences》2020,21(23)
Cudrania tricuspidata has diverse biological activities, such as antioxidant, anti-inflammatory, anticancer, and neuroprotective effects. This study investigated the protective effects of C. tricuspidata fruit extracts (CTFE) against scopolamine (SCO)-induced neuron impairment. The neuroprotective effects of CTFE on SCO-induced memory dysfunction were confirmed in mice using the Barnes maze test. The results showed that co-treatment of SCO and CTFE increased the stay time in the target zone compared with SCO treatment alone. Similarly, the results obtained by the fear conditioning test revealed that SCO-CTFE co-treatment induced the freezing action time under both the contextual fear condition and the cued fear condition compared with SCO treatment alone. Moreover, we showed that CTFE reduced the SCO-induced acetylcholinesterase (AChE) activity, thereby increasing the acetylcholine concentration in mice hippocampal tissues. Consistent with the improvement of memory and recognition function in vivo, our in vitro results showed that CTFE induced cAMP response element binding protein (CREB) and extracellular regulated kinase 1/2 (ERK1/2) activity in PC12 cells and reduced SCO-induced AChE activity. In addition, the microarray results of the hippocampal tissue support our data showing that CTFE affects gene expressions associated with neurogenesis and neuronal cell differentiation markers such as spp1 and klk6. Overall, CTFE exerts a neuroprotective effect via regulation of the CREB and ERK1/2 signaling pathways and could be a therapeutic candidate for neurodegenerative diseases. 相似文献
87.
Sung Yeon Kim Jee Heung Kim Dukjoon Kim Jung Ho An Doo Sung Lee Sung Chul Kim 《应用聚合物科学杂志》2001,82(10):2599-2605
Copolymers of poly(L -lactic acid) and methoxy end-capped poly(ethylene glycol) were synthesized, and their structure and physical properties were characterized. Micellar structures were formed in aqueous media because of the amphiphilic nature of the copolymers, and their sizes were measured with both dynamic light scattering equipment and scanning electron microscopy. Indomethacin was loaded into the copolymer micelles, and its releasing behavior was monitored. The drug-releasing mechanism was determined from an investigation of the biodegradation kinetics of the copolymer micelles. The releasing mechanism was governed by diffusion rather than a biodegradation process. We adapted a model based on Fick's diffusion theory to describe the overall releasing behavior with the extraction of the diffusion coefficient. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2599–2605, 2001 相似文献
88.
Seung-Wook Jee Chun-Ha Lee Si-Kuk Kim Jae-Jin Lee Phil-Young Kim 《Fire Technology》2014,50(3):805-822
Many countries use conventional fire alarm control panels (FACPs) and conventional detectors as fire alarm systems (FASs) because of economic advantages. This study analyzes several problems with conventional FASs and describes an advanced FAS, the traceable FAS, that we developed to solve these problems. The traceable FAS can trace the exact location of a fire, can detect multiple fires that occur simultaneously, and can be used with conventional detectors without disrupting the other detectors operation. The traceable FAS consists of a traceable FACP based on the conventional FACP and a traceable heat detector based on the rate-of-rise spot-type conventional heat detector. The new system offers traceability in addition to all the features of the conventional FAS. The traceable FACP has 40 zones; one zone can connect up to 20 traceable heat detectors. Thus, this FACP can connect up to 800 traceable heat detectors, all of which can detect and trace exact fire locations in sequence. Furthermore, the traceable FACP can be used with both traceable heat detectors and conventional heat detectors in the same zone. Even if one detector (either traceable heat detector or conventional heat detector) detects a fire first, other traceable heat detectors in the same zone can also detect it and display the results on the traceable FACP. Prototypes of the traceable FACP and traceable heat detector (rate-of-rise spot-type) have officially received model approvals for use in South Korea. Conventional FASs can be upgraded to traceable FASs simply by changing to the traceable FACP and traceable heat detectors, without any rewiring. 相似文献
89.
Soo Jeong Kim Kyung Jun Gil HyungSeok Kim Sang Boem Lim Jee‐in Kim 《Computer Animation and Virtual Worlds》2010,21(5):531-543
In this research, we propose a method to adapt the interfaces and interaction processes of heterogeneous devices. The proposed method models the interaction capability of the devices. The interaction is modeled by categorizing elementary actions and measuring its effect in semantic behaviors. With this model, an interaction process can be modified to a given device by changing sequence of elementary actions for each behavior. In the pilot test, we showed the possibility of interaction adaptation for different situations. With the proposed adaptation mechanism, interface and interaction can be modeled for the device independently and can be transferred over different interaction environments. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
90.
A triple-band coplanar waveguide (CPW)-fed LI-shaped monopole antenna is proposed. The antenna is composed of an I-shaped monopole and a meandered L-shaped one. The dimensions of the design are 29 times 28 mm which are 0.077 lambda times 0.075 lambda in terms of the lowest operating frequency of 800 MHz. The antenna operation presents attractive characteristics, each monopole is independently optimised to the resonant frequency and the impedance bandwidth without affecting those of other bands. The antenna shows improved radiation efficiency of individual monopoles for a global system for mobile communication, personal communication systems, digital communication systems, and wireless code division multiple access applications. 相似文献