• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.7
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• pp.1029-1037
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• 2004

High-speed/precision servomechanisms have been widely used in the manufacturing and semiconductor industries. In order to ensure the required high-speed and high-precision specifications in servomechanisms, an integrated design methodology is required, where the interactions between mechanical and electrical subsystems will have to be considered simultaneously. For the first step of the integrated design process, it is necessary to obtain not only strict mathematical models of separate subsystems but also formulation of an integrated design problem. A two-degree-of-freedom controller described in the discrete-time domain is considered as an electrical subsystem in this paper. An accurate identification process of the mechanical subsystem is conducted to verify the obtained mathematical model. Mechanical and electrical constraints render the integrated design problem accurate. Analysis of the system performance according to design and operating parameters is conducted for better understanding of the dynamic behavior and interactions of the servomechanism. Experiments are performed to verify the validity of the integrated design problem in the x-Y positioning system.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.10
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• pp.1398-1402
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• 2002

Hu sheep was sampled randomly from Huzhou city, Zhejiang province, China. Of the 11 genetic markers from the blood examined by starch-gel and cellulose acetate electrophoresis, polymorphisms in Hu sheep were found for 10 loci, i.e. post-albumin (Po), transferring (Tf), alkaline phosphatase (Alp), leucine aminopeptidase (Lap), arylesterase (Ary-Es), hemoglobin-$\beta$ (Hb-$\beta$)、Xprotein(X-p), carbonic anhydrase (CA), catalase (Cat) and lysine (Ly). The same data except for Po locus were collected from another 14 sheep breeds from China and other countries, in order to ascertain their genetic relationships with one another and with the Hu sheep. The sheep populations from the east and south of Central Asia can be classified into three genetic groups: 'Mongolian sheep', 'South Asian sheep' and 'European sheep'. The Hu sheep belong to the 'Mongolian sheep' group.

• Journal of Food Hygiene and Safety
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• v.19 no.2
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• pp.97-103
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• 2004

The present study was performed to investigate photodegradation rate constants and degradation products of piperophos by the USEPA method. The pesticide was very stable in 16 days exposure of sunlight from October 3 to 22, 2003 and humic acid had no sensitizing effect on the photolysis of each pesticide in sunlight. In the UV irradiation test, piperophos was rapidly degraded as increasing UV intensity. In case of UV irradiation with TiO$_2$ and with TiO$_2$ powder amount, degradation of piperophos was slower than UV irradiation. In order to identify photolysis product, the extracts of degradation product was analyzed by GC/MS. The mass spectrum of photolysis product of piperophos was at m/z 166. It was suggested that the photolysis products of piperophos was O, O-dipropyl phosphorodithioate.

• Geomechanics and Engineering
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• v.16 no.2
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• pp.141-150
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• 2018

In this current work a quasi 3D "trigonometric shear deformation theory" is proposed and discussed for the dynamic of thick orthotropic plates. Contrary to the classical "higher order shear deformation theories" (HSDT) and the "first shear deformation theory" (FSDT), the constructed theory utilizes a new displacement field which includes "undetermined integral terms" and presents only three "variables". In this model the axial displacement utilizes sinusoidal mathematical function in terms of z coordinate to introduce the shear strain impact. The cosine mathematical function in terms of z coordinate is employed in vertical displacement to introduce the impact of transverse "normal deformation". The motion equations of the model are found via the concept of virtual work. Numerical results found for frequency of "flexural mode", mode of shear and mode of thickness stretch impact of dynamic of simply supported "orthotropic" structures are compared and verified with those of other HSDTs and method of elasticity wherever considered.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1053-1056
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• 2008

An application of CSG (Constructive Solid Geometry) modeling technique in Machining Simulation is introduced in this paper. The current CSG model is based on z-buffer CSG Rendering Algorithm. In order to build a CSG model, frame buffers of VGA (Video Graphic Accelerator) should be used in term of color buffer, depth buffer, and stencil buffer. In addition to using CSG model in machine simulation Stock and Cutter Swept Surface (CSS) should be solid. Method to create a solid Cuboid stock and Ball-end mill CSS are included in the present paper. Boolean operations are used to produce the after-cut part, especially the Difference operation between Stock and CSS as the cutter remove materials form stock. Finally, a small program called MaSim which simulates one simple cut using this method was created.

• Food Science of Animal Resources
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• v.32 no.5
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• pp.578-583
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• 2012

The purpose of this study was to evaluate the ultrastructural and shear force changes of duck breast and leg meat during aging at $0^{\circ}C$. Pekin ducks (45 d old) purchased from Greemud Co. were used for this experiment, and were stored at $0^{\circ}C$ for 7 d in order to determine the changes of the meat structure using transmission electron microscopy (TEM) and shear force. At day 0, A-band, I-band, M-line and Z-line of sarcomeres were seen clearly, but sarcomeres started to lose structure and become extended in length from day 2. With extended aging periods, myofibrils were destroyed and symptoms of aging became more obvious. In the duck breast meat, some myofibrils were also destroyed at the Z-line, but were mainly destroyed at the M-line. The change in structure of duck leg meat over time was similar to that of breast meat. After five days and seven days of aging, mitochondria size and quantity were determined to be increased between the myofibrils. Shear force was decreased over time. From this study, aging at $0^{\circ}C$ was found to negatively influence the ultrastructure and shear force of duck meat.

• Mass Spectrometry Letters
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• v.2 no.1
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• pp.24-27
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• 2011

Hyperthermal ion/surface collisions of bromotoluene radical cations were studied using perfluorinated (F-SAM) and hydroxyl-terminated (OH-SAM) self-assembled monolayer surfaces in a tandem mass spectrometer with BEEQ geometry. The isomers were differentiated by ion abundance ratios taken from surface-induced dissociation (SID). The dissociation rate followed the order of ortho > meta > para isomers. The peak abundance ratio of m/z 51 to m/z 65 showed the best result to discern the isomers. A dissociation channel leading to tolylium ion was suggested to be responsible for the pronounced isomeric differences. The capability of SID to provide high-energy activation with narrow internal energy distribution may have channeled the reaction into the specific dissociation pathway, also facilitating small differences in reaction rates to be effective in the spectral time window of this experiment. All of the molecular ions experiencing reactive collisions with the F-SAM surface undergo transhalogenation, in which a fluorine atom on the surface replaces the bromine in the incoming ions. This reactive collision was dependent on the laboratory collision energy occurring in ca. 40.75 eV range.

• KSBB Journal
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• v.5 no.4
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• pp.335-339
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• 1990

In order to develop economic processes for ethanol production from starch, a simultaneous saccharification and fermentation(SSF) process using Zymomonas mobilis and amyloglucosidase (AMG) was studied in semibatch modes using cell recycle. The cell recycle was carried out by adopting two different methods; microfiltration and settling. The cell recycle using microfiltration revealed higher productivity(5.4 g/l/h) than that using a settler(4.3 g/l/h). Taking the large-scale ethanol fermentation into account, the semibatch process using microfiltration system appeared most promising among others with respect to ethanol productivity, feasibility of scale-up and simplification of operation.

• Applied Biological Chemistry
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• v.20 no.1
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• pp.101-104
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• 1977

Lipase from Geotrichum candidum was heat inactivated in 0.1M phosphate buffer solution. The thermal inactivation followed first order kinetics for the range of temperatures $50^{\circ}-80^{\circ}C$ except at $50^{\circ}C$. The changes in enthalpy, entropy and Gibbs free energy at $60^{\circ}C$ were 120.4 kJ/mol, 73.0 J/mol K and 96.9 kJ/mol respectively a value of $19^{\circ}C$(Geotrichum candidum lipase) is greater than that of lipases from milk and pancreas. The effect of detergents, lecithin and linoleic acid or the thermal inactivation of lipase was found to be negligible.

• Structural Engineering and Mechanics
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• v.38 no.6
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• pp.803-823
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• 2011

In this paper, the three dimensional Parallel Realistic Failure Process Analysis ($RFPA^{3D}$-Parallel) code based on micromechanical model is employed to investigate the bonding behavior in FRP sheet bonded to concrete in single shear test. In the model, the heterogeneity of brittle disordered material at a meso-scale was taken into consideration in order to realistically demonstrate the mechanical characteristics of FRP-to-concrete. Modified Mohr-coulomb strength criterion with tension cut-off, where a stressed element can damage in shear or in tension, was adopted and a stiffness degradation approach was used to simulate the initiation, propagation and growth of microcracks in the model. In addition, a Master-Slave parallel operation control technique was adopted to implement the parallel computation of a large numerical model. Parallel computational results of debonding of FRP-concrete visually reproduce the spatial and temporal debonding failure progression of microcracks in FRP sheet bonded to concrete, which agrees well with the existing testing results in laboratory. The numerical approach in this study provides a useful tool for enhancing our understanding of cracking and debonding failure process and mechanism of FRP-concrete and our ability to predict mechanical performance and reliability of these FRP sheet bonded to concrete structures.