• Title/Summary/Keyword: Ocher

Search Result 55, Processing Time 0.023 seconds

An Experimental Study on Quality Properties of Living Concrete Using Loess-Magnesia Composites (황토-마그네시아 복합체 활용 Living Concrete의 품질특성에 관한 실험적 연구)

  • Yun-Wang, Choi;Young-Woo, Na;Yong-Woo, Kwon
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.10 no.4
    • /
    • pp.498-505
    • /
    • 2022
  • In this study, as a result of eva lua ting the quality properties of Living Concrete, the flow of the table showed a tendency to decrease as the mixing ratio of ocher increased. Compressive strength was found to decrease with increasing loess mixing ratio. Density properties were evaluated for weight reduction, As a result of comparison with the panel using cement as a comparison group, the density was measured to be a bout 20 % lower than that of the cement panel, and it is judged that it is less affected by the load and can be installed in the structure. As a result of evaluating the panel temperature reduction, there was a difference in the temperature reduction with time. It is judged that the panel planted with moss has a lower temperature than the panel without moss, so it is judged that it can be used in a vertical greening system.

A Small Disk-type Hybrid Self-healing Motor (소형 원판형 하이브리드 자기 부상 모터)

  • ;Yohji Okada
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.11 no.8
    • /
    • pp.338-348
    • /
    • 2001
  • A hybrid self-hearing motor, which Is a functional combination of general permanent magnet (PM) motor and hybrid active magnetic bearing(AMB), was proposed a few years ago. In this paper the hybrid self-bearing motor is modified to a disk type, in which one of two magnetic hearings was substituted for a thin yoke to make the system more compact. An outer rotors in this self-hearing motor is actively controlled only in two radial directions while the ocher motions are passively salable owing to the disk-type structure. Main advantages of the proposed self-hearing motor are simple control mechanism, low power consumption and smart structure. Mathematical model for the magnetic force Is built wish consideration of the radial displacement of the rotor. The model helps us not only to design a levitation controller but also to expect the system performance. Some experimental results show good capability and feasibility of the Proposed self-bearing motor.

  • PDF

Dynamic Stability and Leakage Characteristics of Turbo Pump Unit Installed with High-Pressure Seals (고압 실이 장착되어 있는 터보 펌프의 동적 안정성 및 누설 특성에 관한 연구)

  • 이용복;곽현덕;김창호;하태웅
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.11 no.8
    • /
    • pp.322-330
    • /
    • 2001
  • The stability and the leakage performance of turbo pump unit seals supported by elastic-ring ball bearings are Investigated for the Improvement of onset speed of instability(OSI). The numerical analysis of floating ring seal in consistence with its geometry and operating conditions is executed with detailed comparison of various seal types. The results show that the floating ring seal has superior performance in terms of rotordynamic salability compared to the ocher type seals while it shows slightly inferior leakage performance. To Improve the leakage performance. floating ring seal could be combined with hole Pattern damper or labyrinth seal surface.

  • PDF

Studies on the Artificial Rearing of Mole Cricket, Gryllotalpa orientalis (Orthoptera : Gryllotalpidae)

  • Park, Young-Kyu;Lee, Young-Bo
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • v.25 no.2
    • /
    • pp.175-179
    • /
    • 2012
  • The present study is to develop the rearing method of Gryllotalpa orientalis. In total 429 of G. orientalis were collected from the field rearing cage ($25m^2$) in 2012. Its sex ratio was 1: 1.15(Female : Male). Survival rate of the mole crickets was 94.4~86.1% with the artificial diets formulated for the present study. Successful oviposition rate was 20, 20 and 80% for one, two and three pairs of adult crickets, respectively, from the indoor rearing. The mean number of hatchlings was $11.8{\pm}21.7$, $15.7{\pm}26.4$ and $25.8{\pm}38.8$, and the mean number of dead hatchlings 1.2, 1.7 and 1.2. The mortality of nymphs on horticultural soil and clay sand mixed with ocher was 18.3 and 10.0%, respectively. The mortality of nymphs in circular and rectangular cages was, respectively, 60 and 40%.

A Study on the Preparation Method of Geopolymeric Concrete using Specifically Modified Silicate and Inorganic Binding Materials and Its Compressive Strength Characteristics

  • Kim, Jong Young
    • Journal of the Korean Ceramic Society
    • /
    • v.52 no.2
    • /
    • pp.150-153
    • /
    • 2015
  • Recently, research on geopolymeric concrete that does not use cement as a binder has been actively investigated. Geopolymeric concrete is cement-free concrete. Masato, ocher and/or soil has been solidified into geopolymeric concrete by the reaction of specifically modified silicate as an alkali activator and inorganic binding materials such as blast furnace slag, fly ash or meta-kaolin, which is cured at room temperature to exhibit high compressive strengths. Based on the results, this study shows how geopolymeric concrete that uses specifically modified silicate and inorganic binding materials is implemented as eco-cement with no cement.

A Test for Weibull Distribution and Extreme Value Distribution Based on Kullback-Leibler Information (쿨백-레이블러 정보함수에 기초한 와이블분포와 극단값 분포에 대한 적합도 검정)

  • 김종태;이우동
    • The Korean Journal of Applied Statistics
    • /
    • v.11 no.2
    • /
    • pp.351-362
    • /
    • 1998
  • In this paper, a test of fit for Weibull distribution on the estimated Kullback-Leibler information is proposed. The test uses the Vasicek entropy estimates, so to compute it a window size m must first be fried, and then is obtained critical values computed by Monte Carlo simulations. The power of the proposed test under various alternatives is compares with that of ocher famous tests. The use of the test is shown in an illustrative example.

  • PDF

Lacquer Techniques in the Late Joseon Dynasty

  • Junghae PARK;Jaewan CHOI;Uicheon LEE;Minji KANG;Soochul KIM
    • Journal of the Korean Wood Science and Technology
    • /
    • v.51 no.2
    • /
    • pp.69-80
    • /
    • 2023
  • This study conducted scientific analyses on eight objects of wooden lacquerware to understand the manufacturing techniques of wooden lacquerware in the late Joseon Dynasty. The results of lacquer layer analysis with a microscope and scanning electron microscopy-energy dispersive X-ray spectrometry revealed that most samples were composed of 1-3 lacquer layers. Moreover, a red-colored layer was found to be red ocher and cinnabar, and Fourier-transform infrared spectroscopy analysis was carried out to determine the components of the lacquer layer. The detected components were mostly lacquer and partially cashew shell nut liquid.

Interpretation of Material Characteristics and Making Techniques for Lime-Soil Mixture on Tomb Barrier of Pyeongtaek Gungri Site in Joseon Dynasty (평택 궁리유적 조선시대 회곽묘의 재료학적 특성 및 제작기법 해석)

  • Kang, San Ha;Lee, Chan Hee
    • Economic and Environmental Geology
    • /
    • v.51 no.1
    • /
    • pp.49-65
    • /
    • 2018
  • The lime-soil mixture on tomb barrier (LSMB) is a type of tomb in Joseon Dynasty, which made with so-called 'Sammul' (three material compound) that mixture of lime, fine sand and yellow ocher. This study divided the tombs of the Gungri Site from Joseon Dynasty with layered wall and integrated wall according to the manufacturing types, and investigated on the basis of analysis to material characteristics and making techniques. Analytical samples were classified with lime-soil mixtures and soils, and interpreted the mixing characteristics of Sammul based on types of tomb barrier. The tomb barrier which is directly effect to control the inner environment was made with high content of lime. But the finishing or bottom layer were made with low content of lime. Overall the LSMB with integrated wall has higher content of lime and physical property than the LSMB with layered wall. The soil which was compounded as a Sammul and collected near the Gungri Site had similar with mineralogical and geochemical characteristics. Therefore, it is presumed that the fine sand and yellow ocher that made as a Sammul, were used with soil that was distributed around the site. Meanwhile, large scale limestone quarry is distributed near the site. Especially, Gungri Site has a possibility of material supply through water transport, due to the sea route from Asan bay is connected near the site. Thus, there is the possibility of transportation of lime materials from nearby quarry.

A Scientific Analysis of Dancheong Pigments at Yaksajeon Hall in Gwallyoungsa Temple (창녕 관룡사 약사전 단청안료의 과학적 분석)

  • Han, Min-su;Kim, Jin-hyoung;Lee, Jang-jon
    • Korean Journal of Heritage: History & Science
    • /
    • v.47 no.1
    • /
    • pp.18-31
    • /
    • 2014
  • This study aims at identifying of characteristics and types of the pigments used for Dancheong(surface decorative and protective pigments) of Yaksajeon Hall in Gwallyoungsa Temple using a Micro-XRF, XRD, SEM-EDS and thereafter, comparing it with the pigments of the wall painting in the same building and with Dancheong pigments of Daeungjeon Hall. The results can be briefly summarized as two points. First, different types of pigments for red, green and white colours had been applied based on different parts of the building and more than two different pigments had been mixed to produce various colours in so me parts. Second, scientific analysis has confirmed that raw minerals for each colour groups are: Cinnabar, minium and Hematite for red; white clay and oyster shell white($Al_2O_3{\cdot}SiO_2{\cdot}4H_2O$) for white; Atacamite and Celadonite for green; carbon(C) for black; Yellow Ocher for yellow; and Lazulite for blue. Comparative analysis of such result with that of the wall paintings and of Dancheong of Daeungjeon Hall has revealed that similar minerals had been used in overall except that several different pigments had been added or removed for making green, white and yellow colour groups in some parts. In conclusion, the result has displayed that painters had used different ways of producing pigments by a type of painting or a building within the same period or for the buildings in the same buddhist temple compound.

A study on the Red Painting of stone monuments (비석(碑石)에 칠해진 주사(朱砂)안료에 관한 연구)

  • Shin, Eun-Jung;Han, Min-Su;Kang, Dai-Il
    • Korean Journal of Heritage: History & Science
    • /
    • v.38
    • /
    • pp.359-385
    • /
    • 2005
  • Red ocher, red lead or cinnabar has been as red colorant for ages. Cinnabar of the red pigments has been highly regarded as a valuable ingredient because it represent a symbol of exorcising and a haute image. It was used as a pigment of painting and mural painting, bowl, clothes, rock writing, gravestone, etc. It is powder which dissolves in perilla oil or glue before using. Because it is high-priced, the use of cinnabar may be limited to the privileged class. Therefore, red ocher or red lead was used instead of cinnabar. "Gongsagyunmunrok" demonstrated that government official's gravestonea has been painted red by two colorants in the period of the Goryeo dynasty. However, cinnabar may be used to paint gravestones for the first time in the period of the Three States because it has been transmitted since the times. This study discuss the results obtained from an analysis of the pigments used on the red pigments of the Stone Monuments. The results can be briefly summarized as below; First, the microcrystalline structures seen on the surface section of analyzed pigments, samples of which were taken from various parts of red pigments show that different sizes and shapes of pigment particle. Second, a result of the analysis on the composition and structure of the pigments shows that the main components in their composition are : Red pigments - Red lead($Pb_3O_4$), Cinnabar(HgS) and Hematite($Fe_2O_3$) White pigments - Calcite($CaCO_3$) Especially, we knew that red Stone Monuments were found to be natural mineral pigments, which were used as a singular or a mixture.