• International Journal of Precision Engineering and Manufacturing
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• v.5 no.2
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• pp.60-67
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• 2004

For improving the motion accuracy of hydrostatic tables, a corrective machining algorithm is proposed in this paper. The algorithm consists of three main processes. The reverse analysis is performed firstly to estimate the rail profile from the measured linear and angular motion error, in the algorithm. For the next step, the corrective machining information is obtained based upon the estimated rail pronto. Finally, the motion errors on the correctively machined rail are analyzed by using the motion error analysis method. These processes are iterated until the analyzed motion errors are satisfactory within the target accuracy. In order to verify the validity of the algorithm theoretically, the motion errors calculated by the estimated rail after the corrective machining process, are compared with those by the true rail which is previously assumed as the initially measured value. The motion errors calculated using the estimated rail show good agreement with the assumed values, and it is shown that the algorithm is effective in acquiring the corrective machining information to improve the accuracy of hydrostatic tables.

• BMB Reports
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• v.36 no.4
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• pp.344-348
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• 2003

Protein kinase CKII is composed of two catalytic ($\alpha$ or $\alpha$') subunits and two regulatory ($\beta$) subunits. The $CKII{\beta}$ subunit is thought to mediate the tetramer formation and interact with other target proteins. However, its physiological function remains obscure. In this study, point mutants of $CKII{\beta}$ that are defective for the L41 binding were isolated by using the reverse two-hybrid system. A sequence analysis of the point mutants revealed that Asp-26, Met-52, and Met-78 of $CKII{\beta}$ are critical for L41 binding; Asn-67 (and/or Lys-139) and Met-52 are important for $CKII{\beta}$ homodimerization. Two point mutants, R75 and R83, of $CKII{\beta}$ interacted with L5, topoisomerase $II{\beta}$, and CKBBP1/SAG, but not with the wild-type $CKII{\beta}$. This indicates that $CKII{\beta}$ homodimerization is not a prerequisite for its binding to target proteins. These $CKII{\beta}$ point mutants may be useful in exploring the biochemical physiological functions of $CKII{\beta}$.

• YAKHAK HOEJI
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• v.48 no.1
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• pp.6-12
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• 2004

Near-infrared spectra of methanol-water mixtures and acetonitrile-water mixtures were acquired to find interactions between solvents widely used for reverse-phase liquid chromatography. Mixtures were prepared to give a series of increasing mole fractions of methanol or acetonitrile in water. Data matrices of acquired spectra were analyzed to determine the proper number of principal components of each mixture system using Malinowski's factor indicator function. Initial guess of score matrix and loading matrix were calculated by nonlinear iterative partial least squares (NIPALS) algorithm for faster computation. Iterative target transform factor analysis (ITTFA) was applied to convert the initial estimation of score matrix to true concentration profile and loading matrix to pure spectra of pure components of the mixtures. In case of methanol-water the number of principal components was found to be 4 and those initial guess of factors were converted to the pure spectra of water methanol and two kinds of complexes. In case of acetonitrile-water the number of pure components of the mixtures was found to be 3 and the pure spectrum of acetonitrile-water complex was found. The nonlinear characteristics of concentration profiles of complexes in the solvent mixtures may give a good criteria in understanding their elution characteristics in reverse-phase liquid chromatogrsphy.

• Geotechnical Engineering
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• v.10 no.3
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• pp.17-32
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• 1994

To model the anisotropic behavior of soils in the case of reverse loading, an anisotropic hardening description is proposed on the basis of generalized isotropic hardening(GIH) rule. There is a core of the GIH rule in the allowance of the concept that the center of homology of isotropic hardening can be any proper stress states inside a yield surface. The plastic deformations could be represented for the condition of reverse loading, and an explicit constitutive relationship was formulated by utilizing a simple hardening function. The proposed hardening description has been compared with other anisotropic hardening models. For verification three sets of triaxial test results have been predicted for the drained and undrained behavior of overconsolidated clays and Ko consolidated clays.

• Membrane and Water Treatment
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• v.8 no.2
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• pp.125-136
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• 2017

Reverse osmosis technology is being used on large scale for treatment of ground water, brackish water, wastewater and sea water. The most challenging issue in RO process is carbonate scaling which is directly linked with the efficiency and economy. Considering the natural phenomena of carbonate scaling different adaptations have been made to control scaling on the surface of RO membrane including acid dosage and antiscalant addition. As carbonate scaling is directly related with pH level of feed water, present study describes an experimental approach to reduce scaling on RO membrane by lowering the feed water pH by purging $CO_2$. In this comparative study four different conditions including control process (without any scale inhibitor), with dosage of antiscalant, with purging of $CO_2$ and with co addition of antiscalant and $CO_2$ in a feed stream line; it was established that $CO_2$ is a better appliance to reduce carbonate scaling on the membrane surface by reduce pH of feed stream. It was also observed that $CO_2$ and antiscalant mutually function better for scale control.

• Archives of Plastic Surgery
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• v.48 no.1
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• pp.133-143
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• 2021

Background Extensive research has been conducted on islet transplantation as a possible cure for diabetes. Islet transplantation in the liver via the portal vein has shown remarkable results, but numerous other recipient sites are currently being investigated. We aimed to show the effectiveness of using a muscle flap as a recipient site for islet transplantation. Methods Islet cells were harvested from 12 isogenic Lewis rats, and then diabetes was induced in another 12 isogenic Lewis rats by streptozotocin injection. In six rats, 3,000 islets were transplanted into gastrocnemius muscle flaps, and in the other six rats, the same number of islets were transplanted into the gastrocnemius muscle. The transplanted islet cell function between the two groups was compared by means of blood glucose tests, glucose tolerance tests, immunohistochemistry, and real-time reverse transcription polymerase chain reaction. Results In the muscle flap group, blood glucose levels significantly decreased after islet transplantation. Blood glucose levels were significantly different between the two groups at 3 weeks after transplantation. The muscle flap group showed nearly normoglycemic results upon the glucose tolerance test, whereas the muscle group was hyperglycemic. Immunohistochemical evaluation showed positive results against insulin and glucagon in biopsies of both groups, and the islet cell density was higher in the muscle flap group. There were no statistically significant differences between the two groups in real-time reverse transcription polymerase chain reaction results. Conclusions Our results suggest that muscle flaps are promising candidates for islet cell transplantation.

• Clinical and Experimental Pediatrics
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• v.52 no.7
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• pp.752-755
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• 2009

It is well known that hemodynamic load is one of the most important determinants of cardiac structure and function. Circadian variations in blood pressure (BP) are usually accompanied by consensual changes in peripheral resistance and/or cardiac output. In recent years, reduction in circadian variations in BP and, in particular, loss of nocturnal decline of BP were observed in hypertensive patients with left ventricular hypertrophy (LVH). The patients with only a slight or no loss of nocturnal decline of BP were considered "non-dippers". Regression of LVH was observed after prolonged antihypertensive therapy. Restoration of the circadian rhythm of BP was also observed. However, the classification of patients into "dippers" and "non-dippers" is arbitrary and poorly standardized and repeatable, and in the recent studies, most hypertensive patients with LVH were "dippers". Therefore, we should be particularly cautious about the conclusions drawn using this index. On the other hand, reduced activity of low-pressure cardiopulmonary baroreceptors and impaired day-to-night modulation of autonomic nervous system activity were observed in patients with only LVH. Therefore, alterations in cardiac structure may impair BP modulation. On the other hand, the reverse can also be trueprimary alterations in BP modulation, through a persistently elevated afterload, can increase cardiac mass. Thus, the interrelationship between cardiac structure and BP modulation is complex. Hence, new and more specific methods of evaluating circadian changes in BP are needed to better clarify the abovementioned reciprocal influences.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.3
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• pp.259-263
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• 2005

The changes in secondary electron emission coefficient(${\gamma}$) and work function($\Phi$$_{\omega}$) have been studied on the surface of MgO protective layer aster plasma(Ar. $O_2$) treatment using ${\gamma}$-focused ion beam (${\gamma}$-FIB) system. The values of ${\gamma}$ varied as follows: $O_2$-treated MgO > Ar-treated MgO > Non-treated MgO, and the work functions varied in the reverse order. The result indicates that both the physical etching and the chemical reaction of $O_2$-plasma removed the contaminating materials from the surface of MgO.

• Steel and Composite Structures
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• v.20 no.3
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• pp.513-543
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• 2016

Third order shear deformation theory is used to evaluate electro-elastic solution of a sandwich plate with considering functionally graded (FG) core and composite face sheets made of piezoelectric layers. The plate is resting on the Pasternak foundation and subjected to normal pressure. Short circuited condition is applied on the top and bottom of piezoelectric layers. The governing differential equations of the system can be derived using Hamilton's principle and Maxwell's equation. The Navier's type solution for a sandwich rectangular thick plate with all edges simply supported is used. The numerical results are presented in terms of varying the parameters of the problem such as two elastic foundation parameters, thickness ratio ($h_p/2h$), and power law index on the dimensionless deflection, critical buckling load, electric potential function, and the natural frequency of sandwich rectangular thick plate. The results show that the dimensionless natural frequency and critical buckling load diminish with an increase in the power law index, and vice versa for dimensionless deflection and electrical potential function, because of the sandwich thick plate with considering FG core becomes more flexible; while these results are reverse for thickness ratio.

• Smart Media Journal
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• v.6 no.3
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• pp.9-14
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• 2017

This paper is a study on the hardware implementation of the encryption and decryption block of the lightweight block cipher algorithm LEA which can be used for tiny devices in IoT environment. It accepts all secret keys with 128 bit, 192 bit, and 256 bit sizes and aims at the integrated implementation of encryption and decryption functions. It describes design results of applying pipeline method for performance enhancement. When a decryption function is executed, round keys are used in reverse order of encryption function. An efficient hardware implementation method for minimizing performance degradation are suggested. Considering the number of rounds are 24, 28, or 32 times according to the size of secret keys, pipeline of LEA is implemented so that 4 round function operations are executed in each pipeline stage.