• Bulletin of the Korean Chemical Society
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• v.27 no.5
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• pp.679-686
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• 2006

The positions of $PbI _2$ molecule synthesized into the molecular-dimensioned cavities of $\mid K_6 (Pb _4I_2)(PbI_2) _{0.67}-(H_2O)_2\mid [Si _{12}Al _{12}O _{48}]$-LTA have been determined. A single crystal of $\mid Pb _6\mid [Si _{12}Al _{12}O _{48}]$-LTA, prepared by the dynamic ion-exchange of $\mid Na _{12}\mid [Si _{12}Al _{12}O _{48}]$-LTA with aqueous 0.05 M $Pb _(NO _3)_2$ and washed with deionized water, was placed in a stream of flowing aqueous 0.05 M KI at 294 K for three days. The resulting crystal structure of the product $( \mid K_6 (Pb _4I_2)(PbI_2) _{0.67}(H_2O)_2\mid [Si _{12}Al _{12}O _{48}]$-LTA, a = 12.353(1) $\AA$) was determined at 294 K by single-crystal X-ray diffraction in the space group Pm3 m. It was refined with all measured reflections to the final error index $R_1$ = 0.062 for 623 reflections which $F_o$ > 4$\sigma$($F_o$). 4.67 $Pb ^{2+}$ and six $K^+$ ions per unit cell are found at three crystallographically distinct positions: 3.67 $Pb ^{2+}$ and three $K^+$ ions on the 3-fold axes opposite six-rings in the large cavity, three $K^+$ ions off the plane of the eight-rings, and the remaining one $Pb ^{2+}$ ion lies opposite four-ring in the large cavity. 0.67 $Pb ^{2+}$ ions and 1.34 $I^-$ ions per unit cell are found in the sodalite units, indicating the formation of a $PbI _2$ molecule in 67% of the sodalite units. Each $PbI _2$ (Pb-I = 3.392(7) $\AA$) is held in place by the coordination of its one $Pb ^{2+}$ ion to the zeolite framework (a $Pb ^{2+}$ cation is 0.74 $\AA$ from a six-ring oxygens) and by the coordination of its two $I^-$ ions to $K^+$ ions through six-rings (I-K = 3.63(4) $\AA$). Two additional $I^-$ ions per unit cell are found opposite a four-ring in the large cavity and form $Pb _2K_2I^{5+}$ and $Pb _2K_2I^{3+}$ moieties, respectively, and two water molecules per unit cell are also found on the 3-fold axes in the large cavity.

• Journal of Korea Water Resources Association
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• v.46 no.1
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• pp.35-45
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• 2013

The aim of study is to present how to estimate and use the FRI (Flood Risk Index) for classifying area zones based on regional flooding risk in terms of the integrated flood risk management. To estimate the FRI at a spatial resolution of city/county/town units for the Nakdong River Watershed, the 17 representative flood indexing factors are carefully selected for the three flood indexes, such as PI (Pressure Index), SI (State Index), and RI (Response Index) under the P-S-R (Pressure-State-Response) classification system. Because flood indexing factors are measured at different scales and units, they are transformed into a common domain by the T-Score normalization technique. The entropy weight coefficient method is also applied to calculate the weight of flood indexing factors in order to reduce subjective judgement on the effect of weight coefficients. The three flood indexes of PI, SI, and RI are integrated for an overall value of the FRI to evaluate the flood risk of districts. To examine the practical application of the proposed FRI, the FRI results with/without the weight coefficients are compared with flooding zones of natural disaster risk areas officially announced in 2010. It is expected that the FRI ensured by full verification can make regional protection plans against flooding disasters with respect to causes and characteristics of past floods.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.37
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• pp.10.1-10.5
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• 2015

Background: The aim of this study was to investigate the effect of a botulinum toxin type A (BTX-A) injection in the masseter muscle using electromyography (EMG) in an animal model. Methods: Ten male adult (>3 months of age) New Zealand white rabbits were used. Muscle activity was continuously recorded from 8 hours before to 8 hours after BTX-A injection. The rabbits received unilateral BTX-A injections of either 5 units (group 1, n = 5) or 20 units (group 2, n = 5). Results: The masseter muscle activity of the rabbits was significantly reduced immediately after BTX-A injection (P < 0.05 for both groups). When the results from group 1 were compared with those from group 2, only the peak voltage was significantly decreased in group 2 (P = 0.013). Conclusion: Masseter muscle activity measured by EMG was immediately decreased after a BTX-A injection.

• Mass Spectrometry Letters
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• v.9 no.4
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• pp.105-109
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• 2018

A certified reference material (CRM) for the analysis of inorganic nutrients in nutritional supplements has been developed. Accurate mass fractions of chromium (Cr), iron (Fe), copper (Cu), and zinc (Zn) were determined by isotope dilution inductively coupled plasma mass spectrometry (ID ICP/MS). The measurement results were used to assign certified values for the CRM, which were metrologically traceable to the definitions of the measurement units in the International System of Units (SI). Production of a candidate reference material (RM) and the certification processes are summarized. Each nutrient in the CRM showed good homogeneity, which was estimated using relative standard deviations of the measurement results of twelve bottles in a batch. This CRM is expected to be an important reference to improve reliability and comparability of nutrient analyses in nutritional supplements and related samples in analytical laboratories.

• Phonetics and Speech Sciences
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• v.13 no.1
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• pp.45-51
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• 2021

End-to-end (E2E) automatic speech recognition (ASR) has achieved promising performance gains with the introduced self-attention network, Transformer. However, due to training time and the number of hyperparameters, finding the optimal hyperparameter set is computationally expensive. This paper investigates the impact of hyperparameters in the Transformer network to answer two questions: which hyperparameter plays a critical role in the task performance and training speed. The Transformer network for training has two encoder and decoder networks combined with Connectionist Temporal Classification (CTC). We have trained the model with Wall Street Journal (WSJ) SI-284 and tested on devl93 and eval92. Seventeen hyperparameters were selected from the ESPnet training configuration, and varying ranges of values were used for experiments. The result shows that "num blocks" and "linear units" hyperparameters in the encoder and decoder networks reduce Word Error Rate (WER) significantly. However, performance gain is more prominent when they are altered in the encoder network. Training duration also linearly increased as "num blocks" and "linear units" hyperparameters' values grow. Based on the experimental results, we collected the optimal values from each hyperparameter and reduced the WER up to 2.9/1.9 from dev93 and eval93 respectively.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.2
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• pp.60-64
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• 2011

High sensitivity IR image sensors require materials characteristics with temperature coefficient of resistance (TCR) and IR range absorption. In this study, the metal-dielectric thermo sensitive films (MDTF) based on $(SiO_2)_x-(Ti)_y$ composition were deposited on substrates of germanium and glass by thermal evaporator. The $SiO_2$ : Ti mixture was made from the ratio of 9 : 1, 8 : 2, 7 : 3, 6 : 4, respectively. $(SiO_2)_x-(Ti)_y$ mixture powder was loaded on tungsten boat in evaporator and was 15.5 cm from the substrate. Resistance of $(SiO_2)_x-(Ti)_y$ in the range of 273~333K were measured as a function of temperature. Temperature coefficient of resistance (TCR) was calculated by the resistance variation. Under the various mixture ratios condition, it is possible to obtain $SiO_2$-Ti layers with resistance from units kilo-ohm to hundreds kilo-ohm. Finally, our results showed that Temperature coefficient of resistance (TCR) of these films varies from -1.4 to $-2.6%K^{-1}$.

• Journal of The Korean Association For Science Education
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• v.15 no.1
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• pp.39-53
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• 1995

The purpose of this study was development of 'Environmental Science' of high school appropriate to Sixth Natinal Education Curriculum. In view that ultimate aim of environmental education is forming responsible environmental behaviors and the goals of values and behaviors are as important as knowledges and skills, A new environmental text of high school level was developed and it was based on analysis of seven texts and environmental education in Fifth Korean Curriculum. This text have seven units, 1.Habitates : What're the Meanings?, 2.Nuclear Energy: Can't be Avoid?, 3.Acid Rain : What're the Messages", 4.Ethanol : Is this Future Fuel?, 5.Wastes : A New War!, 6.What're the National and Global Environmental Issues? and 7.Our Water: Can Drink, Really? This text was stressed equally in goals of four environmental education and avoided from the array of knowledges. Therefore included various teaching strategies and independent actions of students. 'Open-ended value learning' and 'free behavior learning' in text were special learning parts for aquisition of values and formation of behaviors. To verify the effects of new developed environmental text, the direct learning was carried out by 286 students in total. Post test scores of experimental groups per each units were significantly higher than those of control groups about four goals, respectively. The Results of questionnaires by 50 teachers from five different schools were as follows. For validity of selecting contents for units, 74% of respondents replied positively. For classification and presentation of four goal-groups, 90% replied positively in validity and 82%, in utility. For validity of various teaching strategies, 88% and for the degree of including student-centered independent actions, 86% replied positively. For importances and expected effects of 'open-ended value learning' and 'free behavior learning', showed positive responses respectively, 88%, 92%. Therefore this text is effective to acheive four goals of environmental education equally.

• International journal of advanced smart convergence
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• v.5 no.3
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• pp.56-60
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• 2016

Body physical technique is to pursuit the dynamic motion by the physical index(PI) and sensory index(SI) on the physical body function. Function of the physical body by the motor condition is organized the dynamic physical system. For the physical motion of signal, we is defined a runout value of the body function by the physical index on the dynamic state. The concept of body physical index was identified the reference of physical index and sensory index by the body technique. As to detect a variation of the body physical technique-runout physical index(BPT-RPI) of the maximum and average and minimum in terms of physical motion, and the dynamic sensory value that was a runout function of the vision variation of the $Vi-{\xi}_{MAX-AVG-MIN}$ with $2.53{\pm}4.85$ units, that was a runout function of the vestibular variation of the $Ve-{\xi}_{MAX-AVG-MIN}$ with ($-0.69{\pm}2.32$)units, that was a runout function of the somatosensory variation of the $So-{\xi}_{MAX-AVG-MIN}$ with ($-1.43{\pm}-1.36$) units. The dynamic physical motion will be to confirm at the variable function of the runout motion for the body function values of dynamic physical index on the BPT-RPI that was identified an evaluation of the physical sensory function by the dynamic physical system. Runout body system was mentioned of a physical body situation by the mild moving and was refer a runout data of dynamic physical nervous index.

• Korean Journal of Oriental Medicine
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• v.13 no.3
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• pp.105-110
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• 2007

This work reports the pulse diagnosis system using FBG sensors which can display pulse signals detected while oriental medical doctors are conducting pulse diagnoses and simultaneously pressing the sensors by three fingers. Each optical fiber has five FBG sensing units fabricated in 2 mm width and 2 mm inter-sensor spacing. Three optical fibers with the FBG units in the parallel line configuration are then placed on each finger-pressing region and thus overall 9 fibers are used for the pulse measurements on the so-called "chon", "gwan", and "ch대k". A fixture holding the optical fiber arrays is able to adjust the height of the FBG sensing units while placing the fibers on the wrist. The pulse signals detected by the FBG sensors from chon, kwan, and chuk have been analyzed using 4 channel spectrum analyzer connected to the optical fibers. The measured pulse signals exhibit variations due to the nonuniform pressure distributions applied. resulting in the differences in the detected pulse signals between fiber lines. However. this work is the first step towards objective and quantitative analyses of the pulse diagnosis in oriental medicine which has traditionally been performed on subjective basis. Future works will be devoted to improving sensor stability, developing the way applying pressure and algorithms reporting the objective classification of the pulse status from systemic measurements using the sensors instead of relying on the clinicians' diagnoses subjectively performed. A successful pulse diagnosis system emerging in the future is expected to contribute to education as well as promoting pulse diagnosis in oriental medicine to the scientific research area.

• Korean Journal of Food Science and Technology
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• v.11 no.4
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• pp.283-290
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• 1979

Partially purified ${\beta}-fructosidase$ (inulase) from Kluyveromyces fragilis was immobilized on Tygon tube and aminoethyl-cellulose, respectively and both preparations were characterized. Silanization of Tygon tube in chloroform at $65^{\circ}C$ and treatment with 10 % glutaraldehyde were critical for the immobilization of inulase on Tygon tube, while 2 % glutaraldehyde was effective for the immobilization on aminoethyl-cellulose. The derivative of Tygon tube showed 11.5 units of inulase activity per g of dried matrix with retention of 22.5 % of original activity against inulin, whereas one of aminoethyl-cellulose showed 39.3 units per g of dired matrix with 53.4 % of retention. Studies of enzyme stability, pH and temperature dependences, and $K_m$ values are presented for inulase and invertase activities of both immobilized enzymes.