• Journal of the Korean Wood Science and Technology
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• v.22 no.2
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• pp.61-70
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• 1994

This study was executed to find the applicability of press drying of tree disk by investigating the shrinkage and drying defect and to form appropriate model by comparing the actual moisture content(MC) and internal temperature in respect of drying time with calculated values based computer simulation to which was applied finite difference method. In press drying disk, heating period, constant drying rate period maintained plateau temperature at 100$^{\circ}C$ and falling drying rate period were significantly distinguished. Actual MC and internal temperature were analogous to those calculated at comparing points. Heat transfer model formed by Fourier's law using specific heat of moist wood and conduction coefficient considering fractional volume of each element of wood cell wall, bound water, free water and air showed applicability as basic data to developing heat expansion, shrinkage and drying stress during press drying. Also mass transfer model formed by Fick's diffusion law using water vapor diffusion coefficient showed applicability. Longitudinal shrinkage was developed by pressure of hot press and tangential shrinkage was restrained by hygrothermal recovery. The heart check, surface check and ring failure were occurred differently in species, but V-shaped crack didn't develop.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.35-35
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• 2010

Understanding the mechanistic details of heterogeneous catalytic reactions will provide a way to tune the selectivity between various competing reaction channels. In this regard, catalytic decomposition of alcohols over the rutile $TiO_2$(110) surface as a model oxide catalyst has been studied to understand the reaction mechanism employing the temperature-programmed desorption (TPD) technique. The $TiO_2$(110) model catalyst is found to be active toward alcohol dehydration. We find that the active sites are bridge-bonded oxygen vacancies where RO-H heterolytically dissociates and binds to the vacancy to produce alkoxy (RO-) and hydroxyl (HO-). Two protons adsorbed onto the bridge-bonded oxygen atoms (-OH) readily react with each other to form a water molecule at ~500 K and desorb from the surface. The alkoxy (RO-) undergoes decomposition at higher temperatures into the corresponding alkene. Here, the overall desorption kinetics is limited by a first-order decomposition of intermediate alkoxy (RO-) species bound to the vacancy. We show that detailed analysis on the yield and the desorption temperatures as a function of the alkyl substituents provides valuable insights into the reaction mechanism. After the catalytic role of the oxygen vacancies has been established, we employed x-ray photoelectron spectroscopy to further study the surface electronic structure related to the catalytically active defective sites. The defect-related state in valence band has been related to the chemically reduced $Ti^{3+}$ defects near the surface region and are found to be closely related to the catalytic activity of the $TiO_2$(110) surface.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.10
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• pp.4957-4976
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• 2016

This paper investigates the error performance of the amplify-and-forward (AF) relaying systems in the context of full-duplex (FD) communication. In addition to the inherent self-interference (SI) due to simultaneous transmission and reception, coexistent FD terminals may cause crosstalk. In this paper, we utilize the information exchange via the crosstalk channel to construct a particular distributed space-time code (DSTC). The residual SI is also considered. Closed-form pairwise error probability (PEP) is first derived. Then we obtain the upper bound of PEP in high transmit power region to provide more insights of diversity and coding gain. The proposed DSTC scheme can attain full cooperative diversity if the variance of SI is not a function of the transmit power. The coding gain can be improved by lengthening the frame and proper power control. Feasibility and efficiency of the proposed DSTC are verified in numerical simulations.

• Archives of Pharmacal Research
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• v.5 no.2
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• pp.79-86
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• 1982

Sulfisoxazole, $C-{11}H_{13}N_{3}S$, crystallized in the orthohombic system, space group Pbca, with a = 14.492(1), b = 11.563(1), c = 14.900(2) $\AA$ and Z = 8. Intensities for 1867(1360 observed) unique reflections were measured on a four-circle diffractometer wirh CuKa radiation ($\lambda$ = 1.5418$\AA$). The structure was solved by heavy atom methods and refined by full-matrix least-squares procedures to a final R of 0.094. The benzene ring plane makes an angle of $68^{\circ}C$ with the plane of the isoxazole ring, which is plannar. The conformational angle formed by the torsional angle C(4)-S-N(2)-C(7) is $54^{\circ}C$. There are two intermolecular hydrogen bonds in the structure. One of them is of the type N-H...H with the length 2.915$\AA$. Thus two dimensional networks of hydrogen bonds form infinite moelcular sheets parallel to the (001) plane. Adjacent sheets are bound together by van der Waals forces.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.3
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• pp.1481-1501
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• 2019

In opportunistic network, the behavior of a node is autonomous and has social attributes such as selfishness.If a node wants to forward information to another node, it is bound to be limited by the node's own resources such as cache, power, and energy.Therefore, in the process of communication, some nodes do not help to forward information of other nodes because of their selfish behavior. This will lead to the inability to complete cooperation, greatly reduce the success rate of message transmission, increase network delay, and affect the overall network performance. This article proposes a hybrid incentive mechanism (Mim) based on the Reputation mechanism and the Credit mechanism.The selfishness model, energy model (The energy in the article exists in the form of electricity) and transaction model constitute our Mim mechanism. The Mim classifies the selfishness of nodes and constantly pay attention to changes in node energy, and manage the wealth of both sides of the node by introducing the Central Money Management Center. By calculating the selfishness of the node, the currency trading model is used to differentiate pricing of the node's services. Simulation results show that by using the Mim, the information delivery rate in the network and the fairness of node transactions are improved. At the same time, it also greatly increases the average life of the network.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.4
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• pp.653-663
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• 2021

There has been a massive increase in household debt in China, especially in the last five of years. Learning from past experiences, the country needs careful forecasting that may help to form new policies or make amendments to the existing ones. This research paper aims to highlight the impact of the monetary policy on household debt in China. The study covers the time period from 1996 to 2020 The study employs a cointegration test, Autoregressive Distributed Lag Bound Test (ARDL) approach, a Augmented Dicky Fuller (ADF) and PP test (PMG) and time series data. The findings suggest on a quantitative analysis using a time-series model in which gdp per capita and interest rate has a positive impact on household debt whereas, cpi doesn't have significant impact. In a short-term variables relationship, household debt responds more to an increase in income than in the long-term. Also, the impact of interest rate changes on household debt is lower than income in the short run.The research suggests that there should be some restrictions on household debt and consumer financing provided to citizens and for this, appropriate leverage measures should be taken in order for the central bank to sustain robust macroeconomic conditions.

• Bulletin of the Korean Chemical Society
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• v.12 no.2
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• pp.214-219
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• 1991

To study the effect of solvents and counterions in Z-DNA crystal of d(5BrC-G-5BrC-G-5BrC-G), we performed the local energy analysis and then molecular dynamics simulations. Since counterions raise serious caging problems in crystal simulations, it is very important to search for the possible positions before simulations. For this purpose, the local energy analysis was done for the whole crystal volume. It is shown from our simulation that counterions along with water molecules play a bridging role to bind adjacent oligomers so as to form the crystal. In this crystal, each water molecule bound to Gua-N2H, either directly or indirectly, hydrates the adjacent anionic phosphate oxygen, and thus assists Gua to be in a syn position. From the simulation, the average root-mean-square deviation of allthe DNA heavy atom coordinates from the X-ray data is $0.99{\AA}$ . The bases are less deviated from the X-ray positions than the phosphates. The temperature factors from the simulation are consistent with those from the X-ray refinement, showing that the phosphates are more mobile than the bases.

• English & American cultural studies
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• v.13 no.1
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• pp.59-81
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• 2013

Samuel Beckett's literary sympathies with underdogs enslaved to authoritative figures, found in his earliest plays, continued in a more or less subdued form in his later plays: Not I is a good case in point thematizing a social authority psychologically embedded within a subject. The incessant bouts of self-defense, or confessional, which Mouth carries out on a dark stage is directed to an inner authority. In Civilization and Its Discontents (1931), Freud's diagnosis for individuals torn between the opposite calls of a social order-- which he called, by turns, civil society, civilization, and culture--and of individual freedom was a "neurosis." What Not I dramatizes seems to be this state of neurosis suffered by a subject bound to the contradictory calls of an internal social authority, which forces Mouth to carry on a confessional till she obtains a symbolically/linguistically viable social title of "I," and of her individualistic denial of the position("what?..who?..no!.. she!.."). Mouth's ordeal on stage does not signify the psychological pressure of the social system, with its disciplinary measures of guilt, justice, and punishment, triumphs over individualistic irregularities and abnormalities, for her "maddened" confession will never see its closure. The opposite psychological forces at work inside Mouth, who is both "in" and "out[side]" "this world," will keep engaging in an eternal battle. In a way, she is a perfect parable about us humans living within a system, "discontent" and hung between the contradictory calls of individualism and social collectiveness.

• Natural Product Sciences
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• v.27 no.2
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• pp.78-85
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• 2021

Through bio-guided isolation, two natural iron chelators were isolated from Mangifera indica L. leaves, identified as mangiferin (1) and iriflophenone-3-C-𝛽-D-glucoside (2). Their iron-chelating activity was compared to that of Desferal^® using bipyridyl assay and EDTA as a standard. Mangiferin showed the highest activity with IC₅₀ value of 0.385 mM (162.85 ㎍/mL). Furthermore, two combinations of mangiferin with Desferal^® (M-D) and iriflophenone-3-C-𝛽-D-glucoside (M-I) were evaluated. The results showed that mangiferin potentiated the iron chelation activity of Desferal^® about 46%, also that M-I combination is a promising candidate formula for iron chelation therapy. In addition, mangiferin and Desferal-iron complexes were prepared and characterized by IR, UV, and Mass spectra to compare their mode of chelation to iron. Their structural stability was studied by DFT calculations. Furthermore, they displayed increased ABTS antioxidant activity when bound to iron as compared to their free form, which enhances their pharmacological importance.

• Bulletin of the Society of Naval Architects of Korea
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• v.19 no.1
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• pp.3-14
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• 1982

In this paper, the sway added mass of a rectangular cylinder in a restricted water is considered by applying Hamilton's principle as the frequency tends to zero. The present method is an extension of Isshiki's method proposed in 1978. In the present method, it is assumed that the fluid velocity distribution in each subdomain of the fluid can be represented by higher order polynomials while Isshiki assumed linear velocity distribution. The fluid flow is assumed as a rotational motion in the present analysis. However, the results obtained from the present method show good agreement with Bai's numerical results for the case of large clearances between a canal wall and a cylinder. From Kelvin's minimum energy theorem, we can see that the value of sway added mass obtained from the present method approaches the upper bound. The approximate formula obtained in the present study takes a simple form which consists of the dimensions of the canal and the cylinder. The present formulae are derived for the cases of a rectangular cylinder swaying at the center of a narrow or wide canal relative to a cylinder, at off-center location in a canal, and in the restricted water with a single wall. From the results of numerical calculation, it is concluded that the sway added mass in restricted waters is more affected by water depth than clearance between a wall and a cylinder.