http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Fukaya, Masashi,Ono, Shigeyoshi,Udo, Ryujiro Korean Society for Fluid machinery 2009 International journal of fluid machinery and syste Vol.2 No.2
We developed a 'multi-point vibration acceleration method' for accurately predicting the cavitation intensity in pumps. Pressure wave generated by cavitation bubble collapse propagates and causes pump vibration. We measured vibration accelerations at several points on a casing, suction and discharge pipes of centrifugal and mixed-flow pumps. The measured vibration accelerations scattered because the pressure wave damped differently between the bubble collapse location and each sensor. In a conventional method, experimental constants are proposed without evaluating pressure propagation paths, then, the scattered vibration accelerations cause the inaccurate cavitation intensity. In our method, we formulated damping rate, transmittance of the pressure wave, and energy conversion from the pressure wave to the vibration along assumed pressure propagation paths. In the formulation, we theoretically defined a 'pressure propagation coefficient,' which is a correlation coefficient between the vibration acceleration and the bubble collapse pressure. With the pressure propagation coefficient, we can predict the cavitation intensity without experimental constants as proposed in a conventional method. The prediction accuracy of cavitation intensity is improved based on a statistical analysis of the multi-point vibration accelerations. The predicted cavitation intensity was verified with the plastic deformation rate of an aluminum sheet in the cavitation erosion area of the impeller blade. The cavitation intensities were proportional to the measured plastic deformation rates for three kinds of pumps. This suggests that our method is effective for estimating the cavitation intensity in pumps. We can make a cavitation intensity map by conducting this method and varying the flow rate and the net positive suction head (NPSH). The map is useful for avoiding the operating conditions having high risk of cavitation erosion.
Does red pigment protect the citrus red mite eggs from UV damage?
Midori Fukaya,Masahiro Osakabe 한국응용곤충학회 2008 한국응용곤충학회 학술대회논문집 Vol.2008 No.10
Survival rate and development of the two spotted spider mite, Tetranychus urticae are decreased by UV-B irradiation (Otsuka and Osakabe, submitted). This is considered to be a reason why this mite prefers lower leaf surfaces host plants. On the contrary, the citrus red mite, Panonychus citri is known to remain on upper leaf surfaces of host plants. Such difference in the distribution was assumed to depend on the difference in UV resistance. Hatchability of P. citri eggs was decreased by UV-B irradiation, yet their eggs were more protected from the UV-B irradiation in company with T. urticae. Eggs of P. citri are reddish, while those of T. urticae are white. To test whether the reddish color invest UV resistance in eggs, pale white eggs of albino strain and reddish eggs of wild type of P. citri were simultaneously irradiated by UV-B. Reddish eggs of wild type showed higher resistant to the UV-B irradiation than the pale-white eggs of albino strain. For the next step, the wild type and the albino eggs of P. citri under UV opaque film (-UV) or under UV transparent film (+UV) were exposed to solar irradiation. Hatchability of albino eggs was signifycantly lower than that of wild type eggs under the + UV condition. Under UV –, both eggs showed higher hatchability than under UV+ conditions. From these results, the wild type eggs of P. citri were likely to have some mechanism protecting itself from ambient UV irradiation, and the red pigment possibly act as a shield againt solar UV radiation. F1 female proceeded by reciprocal crosses between the wild type and the albino strain exhibited reddish body color in their adult stage, indicating that the albino was recessive. Notwithstanding, F1 eggs from the crosses between albino female and wild type male were pale white. After hatching, the F1 larvae also exhibit pale white body color, then the females turned to reddish at their first quiescent stage. F1 progeny from the crosses between wild type female and albino male were all reddish during egg to adult stage. These revealed that the color of eggs and also larvae were conferred as a maternal effect (: eggs of P. citri might be protected by the red pigments as the first gift of their mother.)
Yoshitaka Fukaya,Yasuyuki Aoyagi,Sakiyo Asada,Yoshitaka Kubota,Yoshitaka Okamoto,Toshinori Nakayama,Yasushi Saito,Kaneshige Satoh,Masayuki Kuroda,Hideaki Bujo 생화학분자생물학회 2012 Experimental and molecular medicine Vol.44 No.5
Auto-transplantation of adipose tissue is commonly used for the treatment of tissue defects in plastic surgery. The survival of the transplanted adipose tissue is not always constant, and one of reasons is the accelerated apoptosis of the implanted preadipocytes. We have recently established highly homogeneous preadipocytes, named ccdPAs. The aim of the current study was to evaluate the regulation of the potency of platelet-rich plasma (PRP) on the apoptosis of ccdPAs in vitro. PRP stimulated the proliferation of the preadipocytes in a dose-dependent manner, and the stimulatory activity of 2% PRP was significantly higher than that of 2% FBS or 2% platelet-poor plasma (PPP). The presence of 2% PRP significantly inhibited serum starvation-or TNF-α/cycloheximide-induced apoptosis in comparison to 2% FBS or 2% PPP. DAPK1 and Bcl-2-interacting mediator of cell death (BIM) mRNAs were reduced in the preadipocytes cultured with 2% PRP in comparison to those cultured in 2% FBS. The gene expression levels were significantly higher in cells cultured without serum in comparison to cells cultured with 2% FBS, and the levels in the cells with 2% PRP were reduced to 5-10% of those in the cells without serum. These results indicated that ccdPAs exhibit anti-apoptotic activities, in addition to increased proliferation,when cultured in 2% PRP in comparison to the same concentration of FBS, and that this was accompanied with reduced levels of DAPK1 and BIM mRNA expression in in vitro culture. PRP may improve the outcome of transplantation of adipose tissue by enhancing the anti-apoptotic activities of the implanted preadipocytes.
New PCBN for Heavy Interrupted Cutting of Hardened Steel
Okamura Katsumi,Kukino Satoru,Fukaya Tomohiro 한국분말야금학회 2006 한국분말야금학회 학술대회논문집 Vol.2006 No.1
PCBN tools are used worldwide for machining of hardened steel parts in automotive industries. But in heavy interrupted cutting of hardened steel, the tool life is not so stable by sudden breakage of the cutting edge, and total cost of cutting by PCBN is not so economical compared to the grinding. To solve this problem, new PCBN has been developed. New PCBN has very fine and homogeneous microstructure to increase the toughness of sintered body that it provides a reliable tool life for heavy interrupted cutting.
Computational complexity of state number calculation problem of some bounded classes of Petri net
Atsushi OHTA,Yuki FUKAYA,Kohkichi TSUJI 대한전자공학회 2015 ITC-CSCC :International Technical Conference on Ci Vol.2015 No.6
This paper studies computational complexity of state number decision problem of Petri net. The problem is to decide whether the number of reachable markings of a Petri net is greater than or equal to a given finite integer. It is shown that the problem is PSPACE complete for bounded Petri nets, NP- hard for acyclic free choice workflow nets and weighted state machines.