• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.2
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• pp.78-82
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• 2022

Phenology determines the timing of crop development, and the timing of phenological events is strongly influenced by the temperature during the growing season. In process-based model, leaf area is simulated dynamically by coupling of morphology and phenology module. Therefore, the prediction of leaf appearance rate and final leaf number affects the performance of whole crop model. The dataset for the model equation was collected from SPA R chambers with five different temperature treatments. Beta distribution function (proposed by Yan and Hunt (1999)) was used for describing the leaf appearance rate as a function of temperature. The optimum temperature and the critical value were estimated to be 26.0℃ and 35.3℃, respectively. For evaluation of the model, the accumulated number of onion leaves observed in a temperature gradient chamber was compared with model estimates. The model estimate is the result of accumulating the daily increase in the number of onion leaves obtained by inputting the daily mean temperature during the growing season into the temperature model. In this study, the coefficient of determination (R²) and RMSE value of the model were 0.95 and 0.89, respectively.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.6
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• pp.276-281
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• 2021

In order to manufacture a semiconductor circuit, etching, cleaning, and deposition processes are repeated. During these processes, the inside of the processing chamber is exposed to corrosive plasma. Therefore, the coating of the inner wall of the semiconductor equipment with a plasma-resistant material has been attempted to minimize the etching of the coating and particle contaminant generation. In this study, we synthesized yttrium oxyfluoride (YOF) powder by a solid-state reaction using Y₂O₃ and YF₃ as raw materials. Mixing ratio of the Y₂O₃ and YF₃ was varied from 1.0:1.0 to 1.0:1.6. Effects of the mixing ratio on crystal structure and microstructure of the synthesized YOF powder were investigated using XRD and FE-SEM. The synthesized YOF powder was successfully applied to plasma spray coating process on Al substrate.

• Economic and Environmental Geology
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• v.55 no.5
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• pp.465-475
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• 2022

The seafloor massive sulfide deposits are important mineral resources for base and precious metals, and their ore genesis and metal contents are mainly controlled by wall-rock leaching process and/or magmatic volatile input from the underlying magma chamber. However, the contribution of two different metal sources to the seafloor hydrothermal mineralization significantly varies in diverse geological settings and thus still remains controversial. In this review, mineralogical and geochemical characteristics of SMS deposits from mid-ocean ridges (MORs) and volcanic arcs were investigated to understand the contribution from different metal sources and to suggest future challenges that need to be addressed. As a result, the genetic occurrences of enargite and cubanite, galena and barite indicate the effects of magmatic input and water-rock interaction, respectively. Also, the distributional behaviors of Co, As, and Hg in pyrite and FeS content of sphalerite could be useful empirical indicators to discriminate the significant roles of different metal sources between MOR and Arc settings. To date, as most studies have focused on sulfide samples recovered from the seabed, further studies on magmatic sulfides and sulfate minerals are required to fully understand the genetic history of SMS deposits.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.12 s.138
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• pp.1596-1604
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• 2004

Quality Function Deployment(QFD) is a product development tool which ensures that the voice of the customer needs is heard and translated into products. To develop a sensible brassiere for middle-aged women QFD was adopted. In this study the applicability and usefulness of QFD was examined through the engineering design process for a sensible brassiere for middle-aged women. The customer needs for the wear comfort of brassiere was made by one-on-one survey of 100 women who aged 30-40. The customer competitive assessment was generated by wearing tests of 10 commercial brassieres. The subjective assessment was conducted in the enviornmental chamber that was controlled at $28{\pm}1^{\circ}C,\;65{\pm}3\%RH.$ As a results, we developed twenty-one customer needs and corresponding HOWs for the wear comfort of brassiere. The Customer Competitive Assessment was generated by wearing tests of commercial brassiere. The subjective measurement scale and dimension for the evaluation of sensible brassiere were extracted from factor analysis. Four factors were fitting, aesthetic property, pressure sensation, displacement of brassiere due to movement. The most critical design parameter was wire-related property and second one was stretchability of main material of brassiere. Also, wearing comfort of brassiere was affected by the interaction of initial stretchability of wing and support of strap. Engineering design process, QFD was applicable to the development of technical and aesthetic brassieres.

• Journal of Mushroom
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• v.2 no.1
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• pp.15-20
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• 2004

Pleurotus ostreatus, the oyster mushroom, is one of the most widely cultivated and important edible mushrooms in the world. In order to study the developmental process of P. ostreatus and its regulatory mechanism, a new culturing method needs to be established for inducing the fruiting body and sporulation in the laboratory. In this study, we have examined whether the fruiting body of P. ostreatus can be formed on the plastic petri dish which are commonly used for cell culture in the laboratory. The strain was cultured on $60{\times}15mm$ plastic petri dish with potato dextrose agar media at $28^{\circ}C$ for mycelial growth and then at $18^{\circ}C$ for the formation of primordia and fruiting bodies within plant growth chamber. The development of primordia into fruiting bodies was achieved on cultured dishes under air ventilation. At the primordia stage, the normal formation of fruiting body was blocked by sealing the plastic dish with parafilm. The periods requiring for the formation of primordia and fruiting bodies were examined on the dish culture. About 96% and 76% of cultured samples formed primordia and fruiting bodies under the optimal conditions during ten weeks of culture, respectively. These culturing periods, however, were changed by the mechanical injury treatment to mycelia. As other factors affecting the fruiting body formation, the effects of light and cold shock have been tested. No fruiting formation was observed on the cultured dishes under the dark. The cold shock treatment by storing cultured dishes for one day at $4^{\circ}C$ did not have any significant effects in the fruiting body formation. Spores of fruiting bodies acquired from the petri dishes could be germinated on culture media at $28^{\circ}C$. These results suggest that the fruiting bodies of P. ostreatus can be formed on the experimental petri dish and this dish-culturing method is useful for understanding of the developmental process of P. ostreatus in the laboratory. Furthermore, the dish-culturing method is able to shorten the life cycle of P. ostreatus without requiring large area and expensive device.

• The Journal of Korean Society for Radiation Therapy
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• v.30 no.1_2
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• pp.191-199
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• 2018

Purpose : In this study, we evaluated the usefulness of colloid gel(slime) as a compensator for irregular patient surfaces in radiation therapy. Materials and Methods : For this study, colloid gel suitable for treatment was made and four experiments were conducted to evaluate the applicability of radiation therapy. Trilogy(Varian) and CT(SOMATOM, Siemens) were used as treatment equipment and CT equipment. First, the homogeneity according to the composition of colloid gel was measured using EBT3 Film(RIT). Second, the Hounsfield Unit(HU) value of colloid gel was measured and confirmed by CRIS phantom, Eclipse RTP(Eclipse 13.1, Varian) and CT. Third, to measure the deformation and degeneration of colloid gel during the treatment period, it was measured 3 times daily for 2 weeks using an ion chamber(PTW-30013, PTW). The fourth experiment was compared the treatment plan and measured dose distributions using bolus, rice, colloid gel and additional, dose profiles in an environment similar to actual treatment using our own acrylic phantom. Result : First experiment, density of the colloid gel cases 1, 2 and 3 was $1.02g/cm^3$, $0.99g/cm^3$ and $0.96g/cm^3$. When the homogeneity was measured at 6 MV and 9 MeV, case 1 was more homogeneous than the other cases, as 1.55 and 1.98. In the second experiment, the HU values of case 1, 2, 3 were 15 and when the treatment plan was compared with the measured doses, the difference was within 1 % at all 9, 12 MeV and a difference of -1.53 % and -1.56 % within the whole 2 % at 6 MV. In the third experiment, the dose change of colloid gel was measured to be about 1 % for 2 weeks. In the fourth experiment, the dose difference between the treatment plan and EBT3 film was similar for both colloid gel and bolus, rice at 6 MV. But colloid gel showed less dose difference than bolus and rice at 9 MeV. Also, dose profile of colloid gel showed a more uniform dose distribution than the bolus and rice. Conclusion : In this study, the density of colloid gel prepared for radiation therapy was $1.02g/cm^3$ similar to the density of water, and alteration or deformation was not observed during the radiotherapy process. Although we pay attention to the density when manufacturing colloid gel, it is sufficient in that it can deliver the dose uniformly through the compensation of the patient's body surface more than the bolus and rice, and can be manufactured at low cost. Further studies and studies for clinical applications are expected to be applicable to radiation therapy.

• Korean Journal of Heritage: History & Science
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• v.44 no.3
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• pp.178-199
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• 2011

The ancient tombs found in Bokcheon-dong, Busan originate from the time between the $4^{th}$ and $5^{th}$ centuries, the period of the Three Nations. They are known as the tombs where the Vertical Plate Armour was mainly buried. In 2006, two units of the Vertical Plate Armour were additionally investigated in the tombs No.164 and No.165 which had been constructed at the end of the eastern slope near the hill of the group of ancient tombs in Bokcheon-dong. Throughout this study, the contents of the two units of the Vertical Plate Armour, whose preservation process has been completed, have been arranged, while the group of constructed ancient tombs in Bokcheon-dong from the $4^{th}$ century has been observed through the consideration of the burial pattern. The units of the Vertical Plate Armour from the tombs No.164 and No.165 can be classified as the IIa-typed armor showing the Gyeongju and Ulsan patterns, according to the attribute of the manufacturing technology. Also, they can be chronologically recorded as those from the early period of Stage II among the three stages regarding the chronological recording of the Vertical Plate Armour. While more than two units of the Vertical Plate Armour were buried in the largesized tomb on the top of the hill of the group of ancient tombs, one unit of the Vertical Plate Armour was buried in the small-sized tomb. By considering such a trend, it can be said that in the stage of burying the armor showing the Gyeongju and Ulsan patterns (I-type and IIa-type), different units of the Vertical Plate Armour were buried according to the size of the tomb. However, as the armor showing the Busan pattern (IIb-type) was settled, only one unit was buried. Meanwhile, the tombs No.164 and No.165 can be included in the wooden chamber tomb showing the Gyeongju pattern, which is a slender rectangular wooden chamber tomb with the aspect ratio of more than 1:3. However, according to the trend shown by the buried earthenware, it can be said that there seem to be common types and patterns shared with the earthenware which has been found in the area of Gimhae and is called the one showing the Geumgwan Gaya pattern. In other words, there seem to be close relationships between the subject tombs and the tomb No.3 in Gujeong-dong and the tomb No.55 in Sara-ri, Gyeongju, regarding the types of armor and tombs and the arrangement of buried artifacts. However, the buried earthenware shows a relationship with the areas of Busan and Gimhae. By considering the combined trend of the Gyeongju and Gimhae elements found in one tomb, it is possible to assume that the group of constructed ancient tombs in Bokcheon-dong used to be actively related with both areas. It has been thought that the Vertical Plate Armour used to be the exclusive property of the upper hierarchy until now, since it was buried in the large-sized tomb located on the top of the hill of the group of ancient tombs in Bokcheondong. However, as shown in case of the tombs No.164 and No.165, it has been verified that the Vertical Plate Armour was also buried in the small-sized tomb in terms of such factors as locations, sizes, the amount of buried artifacts and the qualitative aspect. Therefore, it is impossible to discuss the hierarchical characteristic of the tomb just based on the buried units of the Vertical Plate Armour. Also, it is difficult to assume that armor used to symbolize the domination of the military forces. The hierarchical characteristic of the group of constructed ancient tombs in Bokcheon-dong from the $4^{th}$ century can be verified according to the location and size of each tomb. As are sult, the re seem to be some differences regarding the buried units of the vertical plate armour. However, it would be necessary to carry out amore multilateral examination in order to find out whether the burial of the vertical plate armour could be regarded as the artifact which symbolizes the status or class of the deceased.

• Journal of the Korean Vacuum Society
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• v.15 no.6
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• pp.563-575
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• 2006

Ti(C,N) films are synthesized by pulsed DC plasma enhanced chemical vapor deposition (PEMOCVD) using metal-organic compounds of tetrakis diethylamide titanium at $200-300^{\circ}C$. To compare plasma parameter, in this study, $H_2$ and $He/H_2$ gases are used as carrier gas. The effect of $N_2\;and\;NH_3$ gases as reactive gas is also evaluated in reduction of C content of the films. Radical formation and ionization behaviors in plasma are analyzed in-situ by optical emission spectroscopy (OES) at various pulsed bias voltages and gas species. He and $H_2$ mixture is very effective in enhancing ionization of radicals, especially for the $N_2$. Ammonia $(NH_3)$ gas also highly reduces the formation of CN radical, thereby decreasing C content of Ti(C, N) films in a great deal. The microhardness of film is obtained to be $1,250\;Hk_{0.01}\;to\;1,760\;Hk_{0.01}$ depending on gas species and bias voltage. Higher hardness can be obtained under the conditions of $H_2\;and\;N_2$ gases as well as bias voltage of 600 V. Hf(C, N) films were also obtained by pulsed DC PEMOCYB from tetrakis diethyl-amide hafnium and $N_2/He-H_2$ mixture. The depositions were carried out at temperature of below $300^{\circ}C$, total chamber pressure of 1 Torr and varying the deposition parameters. Influences of the nitrogen contents in the plasma decreased the growth rate and attributed to amorphous components, to the high carbon content of the film. In XRD analysis the domain lattice plain was (111) direction and the maximum microhardness was observed to be $2,460\;Hk_{0.025}$ for a Hf(C,N) film grown under -600 V and 0.1 flow rate of nitrogen. The optical emission spectra measured during PEMOCVD processes of Hf(C, N) film growth were also discussed. $N_2,\;N_2^+$, H, He, CH, CN radicals and metal species(Hf) were detected and CH, CN radicals that make an important role of total PEMOCVD process increased carbon content.

• Korean Journal of Environmental Agriculture
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• v.32 no.3
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• pp.179-184
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• 2013

BACKGROUND: Accurate estimates of total direct $CH_4$ emissions from croplands on a country scale are important for global budgets of anthropogenic sources of $CH_4$ emissions and for the development of effective mitigation strategies. Methane production resulted by the anaerobic decomposition of organic compounds where $CO_2$ acts as inorganic electron acceptor. This process could be affected by the addition of rice straw, water management and rice variety itself. METHODS AND RESULTS: Rice (Oryza sativa L. Japonica type, var Samkwangbyeo) was cultivated in four plots: (1) Nitrogen-Phosphorus-Potassium (NPK) ($N-P_2O_5-K_2O$:90-45-57 kg/ha); (2) NPK plus 3 Mg/ha rice straw (RS3); (3) NPK plus 5 Mg/ha rice straw (RS5); (4) NPK plus 7 Mg/ha rice straw (RS7) for 3 years (2010-2012) and the rice straw incorporated in fall (Nov.) in Gyeonggi-do Hwaseong-si. Gas samples were collected using the closed static chamber which were installed in each treated plot of $152.9m^2$. According to application of 3, 5, 7 Mg/ha of rice straw, methane emission increased by 46, 101, 190%, respectively, compared to that of the NPK plot. CONCLUSION(S): We obtained a quantitative relationship between $CH_4$ emission and the amount of rice straw applied from rice fields which could be described by polynomial regression of order 2. The emission scaling factor estimated by the relationship were in the range of IPCC GPG (2000).

• Electrical & Electronic Materials
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• v.12 no.7
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• pp.7-11
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• 1999

Fully sealed field emission display in size of 4.5 inch has been fabricated using single-wall carbon nanotubes-organic vehicle com-posite. The fabricated display were fully scalable at low temperature below 415$^{\circ}C$ and CNTs were vertically aligned using paste squeeze and surface rubbing techniques. The turn-on fields of 1V/${\mu}{\textrm}{m}$ and field emis-sion current of 1.5mA at 3V/${\mu}{\textrm}{m}$ (J=90${\mu}{\textrm}{m}$/$\textrm{cm}^2$)were observed. Brightness of 1800cd/$m^2$ at 3.7V/${\mu}{\textrm}{m}$ was observed on the entire area of 4.5-inch panel from the green phosphor-ITO glass. The fluctuation of the current was found to be about 7% over a 4.5-inch cath-ode area. This reliable result enables us to produce large area full-color flat panel dis-play in the near future. Carbon nanotubes (CNTs) have attracted much attention because of their unique elec-trical properties and their potential applica-tions [1, 2]. Large aspect ratio of CNTs together with high chemical stability. ther-mal conductivity, and high mechanical strength are advantageous for applications to the field emitter [3]. Several results have been reported on the field emissions from multi-walled nanotubes (MWNTs) and single-walled nanotubes (SWNTs) grown from arc discharge [4, 5]. De Heer et al. have reported the field emission from nan-otubes aligned by the suspension-filtering method. This approach is too difficult to be fully adopted in integration process. Recently, there have been efforts to make applications to field emission devices using nanotubes. Saito et al. demonstrated a car-bon nanotube-based lamp, which was oper-ated at high voltage (10KV) [8]. Aproto-type diode structure was tested by the size of 100mm $\times$ 10mm in vacuum chamber [9]. the difficulties arise from the arrangement of vertically aligned nanotubes after the growth. Recently vertically aligned carbon nanotubes have been synthesized using plasma-enhanced chemical vapor deposition(CVD) [6, 7]. Yet, control of a large area synthesis is still not easily accessible with such approaches. Here we report integra-tion processes of fully sealed 4.5-inch CNT-field emission displays (FEDs). Low turn-on voltage with high brightness, and stabili-ty clearly demonstrate the potential applica-bility of carbon nanotubes to full color dis-plays in near future. For flat panel display in a large area, car-bon nanotubes-based field emitters were fabricated by using nanotubes-organic vehi-cles. The purified SWNTs, which were syn-thesized by dc arc discharge, were dispersed in iso propyl alcohol, and then mixed with on organic binder. The paste of well-dis-persed carbon nanotubes was squeezed onto the metal-patterned sodalime glass throuhg the metal mesh of 20${\mu}{\textrm}{m}$ in size and subse-quently heat-treated in order to remove the organic binder. The insulating spacers in thickness of 200${\mu}{\textrm}{m}$ are inserted between the lower and upper glasses. The Y\ulcornerO\ulcornerS:Eu, ZnS:Cu, Al, and ZnS:Ag, Cl, phosphors are electrically deposited on the upper glass for red, green, and blue colors, respectively. The typical sizes of each phosphor are 2~3 micron. The assembled structure was sealed in an atmosphere of highly purified Ar gas by means of a glass frit. The display plate was evacuated down to the pressure level of 1$\times$10\ulcorner Torr. Three non-evaporable getters of Ti-Zr-V-Fe were activated during the final heat-exhausting procedure. Finally, the active area of 4.5-inch panel with fully sealed carbon nanotubes was pro-duced. Emission currents were character-ized by the DC-mode and pulse-modulating mode at the voltage up to 800 volts. The brightness of field emission was measured by the Luminance calorimeter (BM-7, Topcon).