• Bulletin of the Korean Chemical Society
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• v.4 no.1
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• pp.48-54
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• 1983

A magnetic nucleus located on an internal rotor can interact with magnetic fields arising from end-over-end molecular rotation as well as internal rotation. In this paper the expressions for spin-rotational relaxation times, $T_{1.SR}\;and\;T_{2.SR}$, are derived for such nucleus with the anisotropy of molecular rotation explicitly taken into consideration. The derived expressions are shown to be composed of two parts, the contribution from spin-overall-rotation coupling and that from spin-internal-rotation coupling. Some remarks on the use of derived expressions are also provided.

• Journal of the Korean Home Economics Association
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• v.50 no.7
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• pp.81-96
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• 2012

The purpose of this study is to understand consumer values derived from products by the contemporary consumers, as the meaning of a product is extended from the functional utilities to the mediums of fulfilling consumer values. Consumer values have been researched from the marketers' perspectives and, thus, the scales to measure consumer values tend to be too abstract and not always reflective of the consumers' perspectives. Holbrook's typology of consumer values is utilized and the products are classified into four groups according to the product characteristic of the utilitarian versus hedonic, and the consumption spaces of the indoor and outdoor. The findings are as follows. First, the values of efficiency, excellence, ethics, and spirituality are more likely derived from utilitarian products, while the value of play is more likely derived from the hedonic products. Second, the values of efficiency, excellence, and ethics are more likely derived from the indoor products, and values of playfulness, esthetics, status, and respect are more likely derived from the outdoor products. Third, the most frequently mentioned values are the efficiency, playfulness, and status. Fourth, the list of products answered as being representative for four types of products are short to include obvious products such as TV, mobile phone, computer, car, refrigerator, and MP3 player. Both the utilitarian and hedonic values are derived from TV, computer, and mobile phone, while the utilitarian value from refrigerator and car, and the hedonic value from MP3 player, digital camera, and game consoles. The results imply that consumer values should be carefully understood and reflected in developing new products in order to successfully fulfill consumers' underlying needs and requirements.

• The Journal of the Korean dental association
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• v.51 no.12
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• pp.643-649
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• 2013

The aim of this study was to achieve the healing of peri-implantitis defects and the hard tissue regeneration using the augmentation of a xenograft on defect site. Two patients were treated with the surgical approach. With a full muco-periosteal flap elevation, the implant surfaces were exposed and taken the debridement of granulation tissue around the abutment. Each surface of the abutments was prepared with the air-abrasive device (PerioFlow$^{(R)}$) for decontamination. Bovine-derived bone mineral (Bio-Oss collagen$^{(R)}$) was then used to fill the defects, and no membrane was placed on the grafting site. Radiographs and clinical photo was taken to compare from baseline status. Within the limits of the present case, this case shows the significance of the surgical treatment of peri-implantitis. And this also verifies the stability of bovine-derived bone mineral and effectiveness of Air-abrasive device (PerioFlow$^{(R)}$).

• Journal of the Korean Society of Food Science and Nutrition
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• v.3 no.1
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• pp.53-68
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• 1974

The thiohydantoin derivative derived from amino acid was used for the stepwise sequence analysis of peptide or protein from the carboxyl termini. Recently, SUZUKI reported the mass spectrometric identification about a part of these compounds. In this paper, was described the mass spectrometric identification of thiohydantoins derived from 20 amino acids. Mass spectra were obtained with a mass spectrometer, JEOL model JMS-06H and samples were introduced with a direct inlet probe. The molecular ion peaks and fragment ion peaks were identified easily, because these peaks appeared differently every amino acids and specially, it was easy discrimination between leucine and isoleucine. It is suggested that mass spectrometry was one of the useful methods to identify thiohydantoins derived from amino acids.

• Korean Journal of Animal Reproduction
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• v.19 no.3
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• pp.161-169
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• 1995

To investigate the metabolism of various substrates in preimplantation bovine embryos, uptake of glucose and pyruvate, and lactate production were measured in single IVF-derived bovine embryos by a non-invasive method. When the embryos were incubated for 5 h in culture medium supplemented with 1 mM glucose and 0.4mM pyruvate as substrates at each developmental stage, glucose uptake was increased with more advanced developmental stages while pyruvate uptake was decreased. Total lactate producton of 2-cell embryos was significantly higher than that of blastocysts (p<0.05). Both of glucose uptake and lactate production in normal morulae produced in vitro was significantly high compared to the degenerated embryos(p<0.05). The results obtained in the study suggest that pyruvate as an exogenous substrate may be support in bovine embryos until 8-cell stage, whereas glucose may be effective as an energy source after morula stage. In addition, it was proven thatlactate was not effective as an energy source in preimplantation development of IVF-derived bovine embryos.

• Journal of the Korean Statistical Society
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• v.23 no.1
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• pp.115-134
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• 1994

Polynomial errors-in-variables model with one predictor variable and one response variable is defined and an estimator of model is derived following the Booth's linear model estimation procedure. Since polynomial model is nonlinear function of the unknown regression coefficients and error-free predictors, it is nonlinear model in errors-in-variables model. As a result of applying linear model estimation method to nonlinear model, some additional assumptions are necessary. Hence, an estimator is derived under the assumption that the error variances are decrasing as sample size increases. Asymptotic propoerties of the derived estimator are provided. A simulation study is presented to compare the small sample properties of the derived estimator with those of OLS estimator.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.774-781
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• 2006

This paper presents a study on the analytical prediction of vibration transmission from helical gears to the bearing. The proposed method is based on the application of the three dimensional helical gear behaviors and complete description of shaft by the spectral method. Helical gear system used in this paper consists of the driving element, helical gears, shafts, bearings, couplings and load element. In order to describe all translation and rotation motion of helical gears twelve degree of freedom equations of motion by the transmission error excitation are derived. Using these equations, transfer matrix for the helical gear is derived. For the detail behavior of shaft motion, the $12{\times}12$ transfer matrix for the shaft is derived. Transfer matrix for the bearing, coupling, driving element, and load is also derived. Application of the boundary conditions in the assembled transfer matrix produces the forces and displacements in each element of the helical gear system. The effect of the proposed method is shown by numerical example.

• Journal of the Korean Ceramic Society
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• v.28 no.5
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• pp.365-372
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• 1991

LAS (lithium aluminosilicate) sol was synthesized using the hydrolysis-condensation reaction of TEOS, chelated Al(OBus)3 and Li-salt with H2O in alcohol (EtOH+2-Propanol) medium. Effects of important reaction parameters on the properties of sol and gel-derived LAS were examined. The crystallization of the sol-gel derived LAS with ${\beta}$-spodumene composition began at ∼600$^{\circ}C$, and a series of polymorphic transformations occurred as temperature was increased to 1100$^{\circ}C$: amorphous LAS\longrightarrowhexagonal LiAl(SiO3)2\longrightarrow${\beta}$-spodumene. Lowering Li content in the gel enhanced densification and retarded the crystallization significantly. Optimum reaction conditions of LAS sol formation for thin coating applications were derived from rheological measurements, and these can be summarized as: H2O/total alkoxides molar ratio=4, pH=∼2.5, and aging time of ∼250h.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.6
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• pp.1265-1272
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• 1988

Kinematic and dynamic equations of open-loop mechanical systems are derived using the velocity transformation. The velocities of a link are defined by the velocities of the previous link and relative velocities between the links. The velocities and angular velocities are expressed with joint velocities and 6*1 velocity transformation vector. Using the velocity relations, recursive formula are derived and compared to the previous results. The derived recursive formula are modified and applied to the dynamic simulation of a vehicle. The computational efficiency of the vehicle simulation with the derived recursive formula is much enhanced.

• Korean Journal of Pharmacognosy
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• v.49 no.4
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• pp.336-340
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• 2018

Alnus sibirica Fisch. ex Turcz.(AS) geographically distributes in Korea, Japan, Northeast China and Russia. The bark of Alnus species have been used as traditional medicine for the treatment of allergic skin diseases. The content evaluation of compounds which were isolated from the barks of A. sibirica processed enzymatic hydrolysis(EAS); hirsutanonol(1), 5-O-methylhirsutanonol(2), rubranol(3), hirsutenone(4) and muricarpone B(5) was conducted using HPLC. Consequently, in EAS, the content of glycoside was decreased considerably. But the aglycones(1, 3 and 4) were increased highly and 2, 5 were formed newly.