• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.40 no.11
• /
• pp.9-18
• /
• 2003

Two configurations of Film Bulk Acoustic Wave Resonators with acoustic quater-wave bragg reflector layers are theoretically analyzed using equivalent circuits and the difference of their characteristics are discussed. We compare the characteristics of λ/2 mode to those of ideal FBAR with top and bottom electrode contacting air and the characteristics of λ/4 mode to those of ideal FBAR with top electrode contacting air and bottom electrode clamped. We assume that the piezoelectric film is ZnO, the electrode is A1 and the substrate is Si, ABCD parameters are extracted and input impedance is calculated by converting the equivalent circuit from Mason equivalent circuits to the simplified equivalent circuits that ABCD parameters are extracted possible, From the variation of resonance frequency due to the change of thickness of reflector layers and the variation of electrical Q due to the change of mechanical Q of reflector layers, it is confirmed that the reflector layer just under the bottom electrode have the greatest effect on the varation of resonance frequency and electrical Q. It is shown that the number of reflector layers required for the saturation of electrical Q decreases with the increase of the impedance ratio of reflector layers and electrical Q of λ/2 mode is larger than that of λ/4 mode, Electromechanical coupling factor is independent of the number of layers, The impedance ratio of reflector layers becomes larger as the electromechanical coupling factor becomes larger, The electromechanical coupling factor of the two mode are smaller than those of ideal FBARs because of the trapping of acoustic energy in the reflector layers, The insertion loss of the ladder filter decreases with the increase of the number of reflector layers but the bandwidth is not affected much by the number of reflector layers, As the impedance ratio of reflector layers becomes larger the insertion loss becomes smaller and the bandwidth becomes wider, In our analysis of the two mode, characteristics of λ/2 mode appear to be slightly more favorable than that of λ/4 mode

• Journal of Sensor Science and Technology
• /
• v.2 no.1
• /
• pp.101-108
• /
• 1993

$TiO_{2}$/Se : Te heterojunction for color sensor has been fabricated by RF reactive sputtering and thermal evaporation methods onto glass substrate. The optimum deposition condition of $TiO_{2}$ films was such that RF power was 120 W, substrate temperature was $100^{\circ}C$, oxygen concentration was 50%, working pressure was 50 mTorr for the $TiO_{2}$ film thickness of $1000{\AA}$. In this case, the optical transmittance of $TiO_{2}$ film at 550 nm-wavelength was 85%, resistivity was $2{\times}10^9{\Omega}{\cdot}cm$, refractive index was 2.3, and optical bandgap was 3.58 eV. The composition ratio of 0 to Ti by AES analysis was 1.7. When $TiO_{2}$ films were annealed at $400^{\circ}C$ for 30 min. in $O_{2}$ ambient, the optical transmittance of $TiO_{2}$ films at the wavelength range of $300{\sim}580$ nm was improved from 0 to 25%. When Se : Te films were annealed at $190^{\circ}C$ for 1 min., photosensitivity under illumination of 1000 lux was 0.75. The optical bandgap of Se : Te films was 1.7 eV. The structures of Se : Te films were the hexagonal with (100) and (110) orientation. The spectral response of a-Se was improved by the addition of Te, especially in the long wavelength region. The $TiO_{2}$/Se : Te heterojunction showed wide spectral response, and more improved one than that of a-Si film in the blue light region.

• Korean Journal of Environmental Agriculture
• /
• v.27 no.1
• /
• pp.60-65
• /
• 2008

Current soil remediation principles for toxic metals have some limitations even though they vary with different technologies. An alternative technology that transforms hazardous substances into nonhazardous ones would be environmentally beneficial. Objective of this research was to assess optimum conditions for Cr(VI) reduction in soils as influenced by ZVI(Zero-Valent Iron), organic matter and moisture content. The reduction ratio of Cr(VI) was increased from 37 to 40% as organic matter content increased from 1.07 to 1.75%. In addition, Cr(VI) concentration was reduced as soil moisture content increased, but the direct effect of soil moisture content on Cr(VI) reduction was less than 5% of the Cr(VI) reduction ratio. However, combined treatment of ZVI(5%), organic matter(1.75%) and soil moisture(30%) effectively reduced the initial Cr(VI) to over 95% within 5 days and nearly 100% after 30 days by increasing oxidation of ZVI and concurrent reduction of Cr(VI) to Cr(III). The overall results demonstrated that ZVI was effective in remediating Cr(VI) contaminated soils, and the efficiency was synergistic with the combined treatments of soil moisture and organic matter.

• Radiation Oncology Journal
• /
• v.20 no.3
• /
• pp.283-293
• /
• 2002

Purpose : A PC based brachytherapy planning system was developed to display dose distributions on simulation images by 2D isodose curve including the dose profiles, dose-volume histogram and 30 dose distributions. Materials and Methods : Brachytherapy dose planning software was developed especially for the Ir-192 source, which had been developed by KAERI as a substitute for the Co-60 source. The dose computation was achieved by searching for a pre-computed dose matrix which was tabulated as a function of radial and axial distance from a source. In the computation process, the effects of the tissue scattering correction factor and anisotropic dose distributions were included. The computed dose distributions were displayed in 2D film image including the profile dose, 3D isodose curves with wire frame forms and dosevolume histogram. Results : The brachytherapy dose plan was initiated by obtaining source positions on the principal plane of the source axis. The dose distributions in tissue were computed on a $200\times200\;(mm^2)$ plane on which the source axis was located at the center of the plane. The point doses along the longitudinal axis of the source were $4.5\~9.0\%$ smaller than those on the radial axis of the plane, due to the anisotropy created by the cylindrical shape of the source. When compared to manual calculation, the point doses showed $1\~5\%$ discrepancies from the benchmarking plan. The 2D dose distributions of different planes were matched to the same administered isodose level in order to analyze the shape of the optimized dose level. The accumulated dose-volume histogram, displayed as a function of the percentage volume of administered minimum dose level, was used to guide the volume analysis. Conclusion : This study evaluated the developed computerized dose planning system of brachytherapy. The dose distribution was displayed on the coronal, sagittal and axial planes with the dose histogram. The accumulated DVH and 3D dose distributions provided by the developed system may be useful tools for dose analysis in comparison with orthogonal dose planning.

• Journal of Wetlands Research
• /
• v.24 no.4
• /
• pp.345-353
• /
• 2022

A wastewater treatment plant (WWTP) is a major gateway for the engineered nano-particles (ENPs) entering the water bodies. However existing studies have reported that many WWTPs exceed the No Observed Effective Concentration (NOEC) for ENPs in the effluent and thus they need to be designed or operated to more effectively control ENPs. Understanding and predicting ENPs behaviors in the unit and \the whole process of a WWTP should be the key first step to develop strategies for controlling ENPs using a WWTP. This study aims to provide a modeling tool for predicting behaviors and removal efficiencies of ENPs in a WWTP associated with process characteristics and major operating conditions. In the developed model, four unit processes for water treatment (primary clarifier, bioreactor, secondary clarifier, and tertiary treatment unit) were considered. Additionally the model simulates the sludge treatment system as a single process that integrates multiple unit processes including thickeners, digesters, and dewatering units. The simulated ENP was nano-sized TiO₂, (nano-TiO₂) assuming that its behavior in a WWTP is dominated by the attachment with suspendid solids (SS), while dissolution and transformation are insignificant. The attachment mechanism of nano-TiO₂ to SS was incorporated into the model equations using the apparent solid-liquid partition coefficient (Kd) under the equilibrium assumption between solid and liquid phase, and a steady state condition of nano-TiO₂ was assumed. Furthermore, an MS Excel-based user interface was developed to provide user-friendly environment for the nano-TiO₂ removal efficiency calculations. Using the developed model, a preliminary simulation was conducted to examine how the solid retention time (SRT), a major operating variable affects the removal efficiency of nano-TiO₂ particles in a WWTP.

• Applied Chemistry for Engineering
• /
• v.22 no.1
• /
• pp.15-20
• /
• 2011

Poly[2,3-dimethyl-5,8-dithiophene-2-yl-quinoxaline-alt-9,9-dihexyl-9H-fluorene] (PFTQT) and poly[2,3-dimethyl-5,8-dithiophen-2-yl-quinoxaline-alt-10-hexyl-10H-phenothiazine (PPTTQT) based on 2,3-dimethyl-5,8-dithiophen-2-yl-quinoxaline weresynthesized by Suzuki coupling reaction. All polymers were soluble in common organic solvents such as chloroform, chlorobenzene, o-dichlorobenzene, tetrahydrofuran (THF) and toluene. The maximum absorption wavelength and band gap of PFTQT were 440 nm and 2.30 eV, and PPTTQT were 445 nm and 2.23 eV, respectively. The HOMO and LUMO energy level of PFTQT were -6.05 and -3.75 eV, and PPTTQT were -5,89 and -3.66 eV, respectively. The organic photovoltaic devices based on the blend of polymer and PCBM (1 : 2 by weight ratio) were fabricated. Efficiencies of devices were 0.24% (PFTQT) and 0.16% (PPTTQT), respectively. The short circuit current density ($J_{sc}$), fill factor (FF), and open circuit voltage ($V_{oc}$) of the device with PFTQT were $0.97mA/cm^2$, 29% and 0.86 V, and the device based on PPTTQT were $0.80mA/cm^2$, 28% and 0.71 V, 31% and 0.71 V, respectively, under air mass (AM) 1.5 G and 1 sun condition ($100mA/cm^2$).

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.22 no.4
• /
• pp.312-326
• /
• 2020

Generation of weather forecasts at 100 m resolution through a statistical downscaling process was implemented by Korea Meteorological Administration Post- Processing (KMAPP) system. The KMAPP data started to be used in various industries such as hydrologic, agricultural, and renewable energy, sports, etc. Cheorwon area and Jeonbuk area have horizontal planes in a relatively wide range in Korea, where there are many complex mountainous areas. Cheorwon, which has a large number of in-situ and remotely sensed phenological data over large-scale rice paddy cultivation areas, is considered as an appropriate area for verifying KMAPP prediction performance in agricultural areas. In this study, the performance of predicting KMAPP temperature changes according to ecological changes in agricultural areas in Cheorwon was compared and verified using KMA and National Center for AgroMeteorology (NCAM) observations. Also, during the heat wave in Jeonbuk Province, solar radiation forecast was verified using Automated Synoptic Observing System (ASOS) data to review the usefulness of KMAPP forecast data as input data for application models such as livestock heat stress models. Although there is a limit to the need for more cases to be collected and selected, the improvement in post-harvest temperature forecasting performance in agricultural areas over ordinary residential areas has led to indirect guesses of the biophysical and phenological effects on forecasting accuracy. In the case of solar radiation prediction, it is expected that KMAPP data will be used in the application model as detailed regional forecast data, as it tends to be consistent with observed values, although errors are inevitable due to human activity in agricultural land and data unit conversion.

• Sim-seong Yeon-gu
• /
• v.26 no.2
• /
• pp.149-188
• /
• 2011

This thesis presents the research of analytical psycholoy in respect of Jindo Dasiraegi. In a funeral of Jindo, situated in the southern island of Korea, there is a theatrical performance which is called Dasiraegi(rebirth). This research manifested a basic, universal meaning of psychological approach related the implicit of death in performing theatre from a analytic psychological point of view. The characteristics of this theatrical feast are like these ; 1) funeral festival 2) entrance of clown(the existence of antipole and conflict) 3) eroticism 4) active participation of female character 5) difficulty in her delivery 6) the moment of joy thanks to childbirth. The prerequisite of this feast should be a propitious mourning of person dying old and rich. That is, after having a complete life, it could be an entire death. Three main roles in Dasiraegi ; a bat-blind buddhist devotee, a strolling actor teasing men, an apostate monk, theses characters lock horns in a form of triangle conflict relations, then they keep a balance with a fake mourner as a protagonist , modulator and narrator. These characters are indeed clowns who manifested a metaphor as a decent, sacred and reasonable part of shadow regards group consciousness. The alive and the deceased, mourner and fake mourner, piety and confusion, wail and laugh, silence and grumble, death and birth, diverse antipole all coexist then theses are in harmony. The blind devotee and the monk are in antipole, the entertainer(anima) provokes a conflict between them. The infant is a solution as same as a result of conflict. This conflict seems to be eased by birth of a baby which is a symbol of wholeness(ganzheits) but the conflict of antipole is reenacted as insisting his parental right so this solution is leaving the baby to the chief mourner who is fourth character and the first beginning. Unconsciousness, hereby, is negotiating with appeared reality. The Images in unconsciousness are conscious and this new energy in unconsciousness is proceeding towards consciousness, then it became a therapeutic power for the loss of consciousness. Dasiraegi is the play of consolation much more for the alive than the deceased. The death signified not a loss but a resurrection and this intends a transition of new leading independent role for the alive. These make us have more prudent consideration concern the double sense of renewal for the dead and the alive. It is preserved as only a form of drama on stage after disappearance of Dasiraegi in a funeral recently. Dasiraegi was a manifestation of unconsciousness for compensation about the unilateral attitude of group consciousness to the strict death excessively. Therefore, this will enable reflect the relativeness and the attitude which regards the death as the end today.

• Sim-seong Yeon-gu
• /
• v.37 no.2
• /
• pp.184-254
• /
• 2022

Through this thesis, the psychological meaning of the Korean folktale 'the servant who ruined the master's house' was examined. The opposition between the master and the servant is a universal matter of the human psychology. It can be seen as a conflict between the hardened existing collective consciousness and the new consciousness to compensate for and renew it. From different angles, it has become the opposition between man's spiritual and instinctive aspects, between the conscious and the unconscious, or between the ego and the shadow. In the folktale, the master tries several times to get rid of the youngest servant, but the servant uses tricks and wits to steal food, a horse, the youngest sister, and all money from the master, and finally, take his life. It ends with the marriage of the youngest sister and the servant. Enantiodromia, in which the master dies, and the servant becomes the new master, can be seen that the old collective consciousness is destroyed, and the new consciousness that has risen from the collective unconscious takes the dominant position. In an individual's psychological situation, it can be seen that the existing attitude of the ego is dissolved and transformed into a new attitude. In the middle of the story, the servant marries the youngest sister by exploiting naive people to rewrite the back letter written by the master to kill him. This aspect can be understood negatively in the moral concept of collective consciousness, but it can also be seen as a process of integrating mental elements that have been ignored in the collective consciousness of the Joseon Dynasty, symbolized by a woman, a honey seller, and a hungry Buddhist monk. The new consciousness, represented by the servant, has the characteristics of a trickster that is not bound by the existing frame, so it can encompass the psychological elements that have been ignored in the collective consciousness. Such element may represent compensation or an alternative to the collective consciousness in the late Joseon Dynasty. The master puts the servant in a leather bag and hangs it on a tree to kill the servant. However, the servant deceives a blind man; he opened his eyes while hanged. Instead of the servant, the blind man dies, and the servant is freed. As the problem of the conflict between master and servant is finally entrusted to the whole spirit (Self) symbolized by a tree, the blind man gets removed. It can be understood as an intention of the Self to distinguish and purify the elements of recklessness, stupidity, and greed included in the trickster. Through these processes, the servant, which symbolizes a new change in collective consciousness or a new attitude of ego, solves the existing problems and takes the place of the master. While listening to the cunning servant's performance, the audience feels a sense of joy and liberation. At the same time, in the part where the blind man and the master's family die instead and the servant becomes the master, they experience feelings of fear and concern about the danger and uncontrollability of the servant. The tricksters appearing in foreign analogies are also thoroughly selfish and make innocent beings deceive or die in order to satisfy their desires and escape from danger. Efforts to punish or reform these tricksters are futile and they run away. Therefore, this folktale can also be seen as having a purpose and meaning to let us know that this archetypal shadow is very dangerous and that consciousness cannot control or assimilate it, but only awe and contemplate it. Trickster is an irrational manifestation of revivifying natural energy that rises from the unconscious as a compensation for hardened existing structure and order. The phenomenon may be destructive and immoral from the standpoint of the existing collective mind, but it should be seen as a function of the collective unconscious, a more fundamental psychic function that cannot be morally defined. The servant, a figure of the trickster archetype, is a being that brings transformation and has the duality and contradiction of destructiveness and creativity. The endings of this folktale's analogies are diverse, reflecting the diversified response of the audience's mind due to the ambivalence of the trickster, and also suggesting various responses toward the problem of the trickster from the unconscious. It also shows that the trickster is a problem of inconclusive and controversial contradictions that cannot be controlled with a conscious rational attitude, and that we can only seriously contemplate the trickster archetype within us.

• Journal of Nutrition and Health
• /
• v.42 no.7
• /
• pp.650-663
• /
• 2009

The purposes of this study were to investigate one portion size of menus served and to evaluate nutrient intake of lunch at three elderly care facility food services located in Seoul. A weighed plate method was employed to measure plate wastes and consumption of the menus served. Yield factors were calculated from cooking experiments based on standardized recipes, and were used to evaluate nutrient intake. One hundred elderly participated in this study for measuring plate waste and were asked to complete questionnaire. Nutrient analyses for the served and consumed meal were performed using CAN program. The yield factors of rice dishes after cooking are 2.4 regardless of rice dish types, 1.58 for thick soups, 0.60 to 0.70 for meat dishes, and 1.0 to 1.25 branched vegetable. Average consumption quantity of dishes were 235.97 g for rice, 248.53 g for soup, 72.83 g for meat dishes, 39.80 g for vegetables and 28.36 g for Kimchi. On average the food waste rate is 14.0%, indicating the second highest plate waste percentage of Kimchi (26.2%), and meat/fish dish (17.3%). The evaluation results of NAR (Nutrition Adequacy Ratio) showed that iron (0.12), calcium (0.64), riboflavin (0.80), and folic acid (0.97) were less than 1.0 in both male and female elderly groups, indicating significant differences of NAR among three facilities. Compared to the 1/3 Dietary Reference Intake (DRIs) for the elderly groups, nutrient intake analysis demonstrated that calcium (100%) and iron (100%), followed by riboflavin, vitamin A, and Vitamin B6 did not met of the 1/3 EAR (Estimated Average Requirement). For the nutritious meal management, a professional dietitian should be placed at the elderly care center to develop standardized recipes in consideration of yield factors and the elderly's health and nutrition status.