• Journal of the Korea Furniture Society
• /
• v.24 no.4
• /
• pp.329-344
• /
• 2013

Metal furniture design in this study from the 1960s to the present period of office space by Metal furniture design Metal furniture for social factors in the development. In other words, social and economic characteristics, and the country's formative characterize metal office furniture design characteristics and the development of culture is to provide an opportunity to understand. The scope of this study, including the development of office automation in the 1960s, causing a drastic change in the world at the time of furniture developed in Germany, Italy, the United States, Japan, and examine each country's furniture and metal furniture from the 1960s to the present design trends in office organize, and research methods literature and various data classification by age and by extracting the key trends are established form. The results of this study and the design tends to obscure the distinction between two different aspects of the design appear rarely common or different forms of expression are characterized by two. This furniture range has expanded to use metal and metal to minimize the negative aspects of a conventional flexible image is designed to suit the tastes of modern design and metal furniture design, interior space, except that now it is considered that the most can be identified.

• The Journal of Korean Academy of Prosthodontics
• /
• v.29 no.3
• /
• pp.181-196
• /
• 1991

The Purpose of this study was to evaluate the marginal fit of ceramo-metal crown according to the different ceramo-metal alloy types and the curvature of labio-cervical margin. Degudent $G^{(R)}$ as precious and $Verabond^{(R)}$ as non-precious ceramo-metal alloy were used. The abutment was preparaed with two different curvature types : a normal curvature type and a pronounced curvature type. 20 crowns were farbricated using four different combinations and their marginal fits were measured at 3 consecutive stages (before degassing, after degassing, after glazing) using microscope under 200 magnification. The results were as follows: 1 . Marginal fitness before degassing. The groups of precious ceramo-metal exhibited better marginal fit than the groups of non-precious ceramo-metal with significant difference(P<0.05) . In the same ceramo-metal groups, the normal curvature group exhibited better marginal fit than the pronounced curvature group but without significant difference(P>0.05). 2. Marginal fitness after degassing. By degassing, the group of pronounced curvature and non-precious ceramo-metal was deformed the most, and the degree of margin fitness of each group was the same as before degassing. 3. Marginal fitness after glazing The group of normal curvature and precious ceramo-metal exhibited better marginal fit than the group of pronounced curvature and non-precious ceramo-metal with significant difference(P>0.05), and the degree of margin fitness of each group was the same as before degassing.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.16 no.2
• /
• pp.147-152
• /
• 2016

In this study, we fabricated Ag-based electrochemical metallization memory devices which is also called conductive-bridge random-access memory (CBRAM) in order to investigate the resistive switching behavior depending on the bottom electrode (BE). RRAM cells of two different layer configurations having $Ag/Si_3N_4/TiN$ and $Ag/Si_3N_4/p^+$ Si are studied for metal-insulator-metal (MIM) and metal-insulator-silicon (MIS) structures, respectively. Switching voltages including forming/set/reset are lower for MIM than for MIS structure. It is found that the workfunction different affects the performances.

• Proceedings of the KIEE Conference
• /
• 1997.07d
• /
• pp.1519-1521
• /
• 1997

In this paper, poly (N-(2-4-imidazolyl) ethyl) maleimide-alt-1-octadecene (IMI-O) polymer which can complex metal ion was used to confirm the possibility of molecular device made by Langmuir-Blodgett method. Metal/Insulator/Metal (MIM) device was fabricated for investigation of electric properties. In the ${\pi}$-A isotherm, surface pressure at collapse point was different as to the molecular weight of metal ion complexed respectively, In I-V characteristics, currents of MiM devices were different at the same voltage. It was thought that phenomena was occurred by interaction between function group and metal ion.

• Journal of Electrochemical Science and Technology
• /
• v.14 no.4
• /
• pp.349-360
• /
• 2023

This study investigated the tri-metallic galvanic coupling of different metals in the tubes, fillers, and fins of a heat exchanger. The goal was to prevent corrosion of the tubes using the fin as a sacrificial anode while ensuring that the filler metal has a more noble potential than the fin, to avoid detachment. The metals were arranged in descending order of corrosion potential, with the noblest potential assigned to the tube, followed by the filler metal and the fin. To address a reduction in protection current of the fin, the filler metal was modified by adding Zn to decrease its corrosion potential. However, increasing the Zn content of filler metal also increases its corrosion current. The study examined three different filler metals, considering their corrosion potential, and kinetics. The results suggest that a filler metal with 1.5 wt.% Zn addition is optimal for providing cathodic protection to the tube while reducing the reaction rate of the sacrificial anode.

• The Journal of Advanced Prosthodontics
• /
• v.3 no.3
• /
• pp.113-118
• /
• 2011

PURPOSE. The objective of the present study was to evaluate the effect of five different metal framework designs on the fracture resistance of the metal-ceramic restorations. MATERIALS AND METHODS. For the purpose of this study, the central incisor tooth was prepared, and the metal analogue of it and a master die were fabricated. The counter die with the 0.5 mm clearance was used for fabricating the wax patterns for the metal copings. The metal copings with five different metal framework designs were designed from Group 1 to 5. Group 1 with the metal collar, Group 2, 3, 4 and 5 with 0 mm, 0.5 mm, 1 mm and 1.5 mm cervical metal reduction respectively were fabricated. Total of fifty metal ceramic crown samples were fabricated. The fracture resistance was evaluated with the Universal Testing Machine (Instron model No 1011, UK). The basic data was subjected to statistical analysis by ANOVA and Student's t-test. RESULTS. Results revealed that the fracture resistance ranged from 651.2 to 993.6 N/$m^2$. Group 1 showed the maximum and Group 5 showed the least value. CONCLUSION. The maximum load required to fracture the test specimens even in the groups without the metal collar was found to be exceeding the occlusal forces. Therefore, the metal frameworks with 0.5 mm and 1 mm short of the finish line are recommended for anterior metal ceramic restoration having adequate fracture resistance.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.30 no.2
• /
• pp.87-98
• /
• 2020

Objective: The purpose of this study was to propose a sequential procedure for the simultaneous analysis of soluble and insoluble metal compounds. Methods: Methods for sampling and analyzing metal compounds such as ISO standards, NIOSH methods, HSE methods, and OSHA methods were reviewed. Results: Some metals have different OELs depending on the solubility of the compound. Therefore, we should take into account these characteristics and perform an exposure assessment. Soluble metal compounds are first extracted from the filter, and then the filter is digested by acids to analyze residual insoluble components. The extraction of soluble compounds can be completed by agitation for about 60 minutes with a leach solution (water) in a water bath at 37℃. For the analysis of insoluble compounds, the sample filter and the filtration filter remaining after the extraction of the soluble compounds are analyzed. This allows simultaneous determination of soluble and insoluble metal compounds. For hexavalent chromium compounds, soluble hexavalent chromium can first be extracted from the filter by using sulfate buffer. The insoluble hexavalent chromium remaining in the filter can then be extracted using carbonate buffer. Conclusion: Workers are often exposed to many hazardous substances with different exposure limits at industrial sites. The OELs for compounds of the same metal can be set differently depending on solubility. This study can help evaluate a worker's exposure to metal compounds by suggesting methods for the simultaneous determination of soluble and insoluble metal compounds.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.10 no.6
• /
• pp.158-165
• /
• 2002

This study was to evaluate mechanical properties and toughness of the Al5083-O aluminum alloy welding zone according to the mixing shield gas ratio and heat input change. The GMA(Gas Metal Arc) welding of the base metal was carried out with four different mixing shield gas ratios(Ar100%+He0%, Ar67%+He33%, Ar50%+He50%, and Ar33%+He67%) and three different heat inputs(low, medium, and high). To investigate the Charpy absorbed energy of the weld zone, the specimens were divided base metal, weld metal, fusion line, and HAZ notched specimen according to the worked notch position. The different gas ratio and heat input had little effect upon the tensile strength. But Ar33%+He67% mixture had the greatest mechanical properties considering that the more He gas ratio concentrations, the higher yield strength and elongation. The maximum load and displacement of the weld metal notche specimen was so much low more than that of the base metal, but fusion line and HAZ notched specimens showed almost same regardless of the mixing shield gas ratio and heat input. The Charpy absorbed energy was lowest in weld metal notched specimen, and increased in the fusion line, and HAZ notche specimen in order. Ar33%+He67% mixture had the greatest toughness considering that the more He gas ratio, the higher absorption energy.

• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.4
• /
• pp.591-596
• /
• 2011

The applications of chemical fertilizers and various types of organic materials may cause heavy metal accumulation in soil. In this study, we conducted to investigate the relationship between the different chemical forms of heavy metals such as Cr, Cd, Pb, Cu, Ni, and Zn retained in soil and the metal concentrations in Korean raspberry plant. Forty five soil samples were collected from 2 to 6 years old Korean raspberry cultivation fields (RCFs), Gochang, Korea, to determine total, exchangeable (1.0 M $MgCl_2$-extractable), DTPA-extractable metal contents. The leaves and fruits of raspberry plant were sampled at harvest stage. Total metal contents in soils ranged from $0.87mg\;kg^{-1}$ to $66.82mg\;kg^{-1}$. Exchangeable and DTPA-extractable metals ranged between 0.02 and $0.67mg\;kg^{-1}$ and between $0.05mg\;kg^{-1}$ and $7.07mg\;kg^{-1}$, respectively. The metal concentrations in the plant leaf and fruit determined on a dry-basis were between $1.30mg\;kg^{-1}$ and $38.82mg\;kg^{-1}$ and between $0.05mg\;kg^{-1}$ and $21.51mg\;kg^{-1}$, respectively, but Cd and Pb were not detected in the leaf. The total, exchangeable, and DTPA-extractable contents of the metal ions in soil were directly correlated one another, but the contents of different metals in the different fractions were inversely correlated in general. Most of total and DTPA-extractable metals in the soil were directly correlated with the contents of the same metals in the plant, whereas exchangeable metals in the soil were not statistically correlated with the same metals in plants. Thus, we concluded that the metal contents in the raspberry field soils were much lower thanthe levels of Soil Contamination Warning Standard (SCWS), and the plant metal concentrations were also less than the maximum permissible limits. The total and DTPA-extractable metals in the soil were closely related to the metal concentrations in the plant.

• Journal of The Korean Astronomical Society
• /
• v.21 no.2
• /
• pp.173-181
• /
• 1988

The usual method of classification for metal poor stars is based on the normal standard stars. In this study, we show that among the sample of stars classified by this method, a systematic bias in the observed classes of metal weakness is found and, also that this method is not appropriate for classification of metal poor stars, by showing that the spectral line dependences on the temperature and pressure in the extreme metal poor stars are different from those in the normal standard stars. Therefore, we suggest that the 3-dimensional classification system, like 2-dimensional MK system, is necessary for an accurate classification of metal poor stars.