• Title/Summary/Keyword: Power Stone

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Optimization of the Backfill Materials for Underground Power Cables considering Thermal Resistivity Characteristics (I) (열저항 특성을 고려한 지중송전관로 되메움재의 최적화(I))

  • Kim, You-Seong;Cho, Dae-Seong;Park, Young-Jun
    • Journal of the Korean Geosynthetics Society
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    • v.10 no.4
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    • pp.113-121
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    • 2011
  • River sand has generally used for the backfill material of underground power cables. The thermal resistivity of it has $150^{\circ}C$-cm/Watt in wet condition and more than double in dry condition. The final goal of this study is to find the backfill material which has a small change in thermal resistivity with various water contents, for example thermal resistivity is $50^{\circ}C$-cm/Watt and $100^{\circ}C$-cm/Watt in wet and dry conditions respectively. In this study it is presented that the comparison of thermal resistivity using stone powder, crush rock, weathered granite soil and Jumunjin sand as well as river sand in the needle method regarding water content, dry unit weight and particle size distribution. As a result, the thermal resistivity of a material is minimized when they have maximum dry unit weight at optimum moisture content and maximum density by appropriately mixing materials for particle size distribution. Therefore thermal resistivity characteristics should be considered two factors: one is the difference between natural dry condition and dry state after optimum moisture content, and the other is the difference between unit weight of raw material and maximum dry density.

The Historical Development of Beliefs in the Thunder God and their Magico-ritual Techniques as Viewed from the Perspective of Korean National Religious History (한국의 뇌신(雷神) 신앙과 술법의 역사적 양상과 민족종교적 의미)

  • Park, Jong-chun
    • Journal of the Daesoon Academy of Sciences
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    • v.31
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    • pp.49-92
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    • 2018
  • I have examined some beliefs in the Thunder God and their magico-ritual techniques in Korea from the perspective of Korean national religious history and have classified these types of beliefs. In several myths from ancient nations in Korea, the Thunder God was the Supreme being governing the Universe including the sky, earth, and water, and he justified political power transcendently. In the medieval period, the Thunder God who was called 'the Supreme God and Celestial Worthy of the Ninth Heaven Who Spreads the Sound of the Thunder Corresponding to Primordial Origin' was the object of Daoist ritual for rain. In the early Joseon period, people believed that the prehistoric stone tools known as thunder axes were the tools of the Thunder God, and thereby were imbued with medicinal power. In the late Joseon period, beliefs in the Thunder God developed in various ways such as the overcoming of wars and healing of diseases. Modern Korean national religions including Daesoon Jinrihoe reappropriated the Thunder God called 'the Supreme God and Celestial Worthy of the Ninth Heaven Who Spreads the Sound of the Thunder Corresponding to Primordial Origin' from the perspective of the Great Opening (Kaebyŏk) and the resolution of grievances (Haewon).

Characterization of Noerog, A Traditional Green Mineral Pigment (전통 녹색 석채로 사용된 "뇌록"의 특성연구)

  • Do, Jin-Young;Lee, Sang-Jin;Kim, Soo-Jin;Yun, Yun-Kyung;Ahn, Byung-Chan
    • Journal of the Mineralogical Society of Korea
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    • v.21 no.3
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    • pp.271-281
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    • 2008
  • The "Noerog", a traditional green mineral pigment occurs as veins or cavity-filings in the basaltic pyroclastic rocks of Quaternary Epoch in Mt. Noeseong in Janggi-myeon, Pohang. The "Noerog stone" mainly consists of celadonite with minor chlorite/smectite, mordenite and opal. Celadonite grains are several hundreds to several tens of ${\mu}m$ in size. The particle sizes under several tens of fm are likely to coagulate to aggregates. The coloring rate increases rapidly with decreasing particle size under $71{\mu}m$. The hiding power is maximum in the particle sizes of $0.2\sim0.3{\mu}m$. The resistance properties of the Noerog to both the light and the bacteria are absolutely superior to ordinary chemical pigments. The transparency of the Noerog is maximum in the nano-powders under 200 nm. Examination of the color of the Noerog pigment which has been prepared by traditional technique for "dancheong" shows that the best coloring effect is found in the particle sizes under $32{\mu}m$ and that the painting was not successful for the Noerog of particle size over $32{\mu}m$.

Analysis on the Characteristics of Rock Blasting-induced Vibration Based on the Analysis of Test Blasting Measurement Data (시험발파 계측자료 분석을 통한 암석 발파진동 특성 분석)

  • Son, Moorak;Ryu, Jaeha;Ahn, Sungsoo;Hwang, Youngcheol;Park, Duhee;Moon, Duhyeong
    • Journal of the Korean GEO-environmental Society
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    • v.16 no.9
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    • pp.23-32
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    • 2015
  • This study examined blast testing measurement data which had been obtained from 97 field sites in Korea to investigate the comprehensive characteristics of rock blasting-induced vibration focusing on the effect of excavation types (tunnel, bench) and rock types. The measurement data was from the testing sites mostly in Kangwon province and Kyungsang province and rock types were granite, gneiss, limestone, sand stone, and shale in the order of number of data. The study indicated that the blasting-induced vibration velocity was affected by the excavation types (tunnel, bench) and bench blasting induced higher velocity than tunnel blasting. In addition, the vibration velocity was also highly affected by the rock types and therefore, it can be concluded that rock types should be considered in the future to estimate a blasting-induced vibration velocity. Furthermore, the pre-existing criteria was compared with the results of this study and the comparison indicated that there was a discernable difference except for tunnel blasting results based on the square root scaling and therefore, further studies and interests, which include the effects of rock strength, joint characteristics, geological formation, excavation type, power type, measurement equipment and method, might be necessarily in relation to the estimation of blasting-induced vibration velocity in rock mass.

A Literatural Study on the Traditional Korean Medical Physiotherapy (한방물리요법에 대한 문헌적 고찰)

  • Choi, Bo-Mi;Hong, Seo-Young
    • Journal of Korean Medicine Rehabilitation
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    • v.21 no.2
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    • pp.211-226
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    • 2011
  • Objectives : The purpose of this study is to establish literatural evidence about traditional Korean medical physiotherapy through literatural review. Methods : Applicable paragraphs which were related to the traditional Korean medical physiotherapy were phrased from in "Hwang-je-nae-gyung(黃帝內經)", "Yumun-sa-chin(儒門事親)", "Geum-guei-yo-ryack(金匱要略)", "Eui-hack-ip-mun(醫學入門)", "Gyung-ack-jeon-seo(景岳全書)", "Eui-hack-gang-mock(醫學綱目)", "Dong-eui-bo-gam(東醫寶鑑)" where were archiving of Oriental or Korean medicine literatures. Searched paragraphs were analysed for establishing historical and theoretical bases of Korean medical physiotherapy. Results : 1. Theromtherapy is originated from yu(熨), hot hand, warm, water bath, warm earth, fumigation, lamp, torchlight and brazier. Matching indications are various musculoskeletal pain and diseases, skin diseases such as chronic inflammation, frostbite, gynecological and urogenital diseases such as uterine myoma, lower abdominal pain, metrorrhagia, breast diseases, digestive tract diseases such as vomiting, diarrhea, stomachache and also it treats cardiovascular disease. Other matching indications are sunstroke, rhinorrhea, psycosis and anal pain. And it used helping acupuncture therapy. 2. Cryotherapy is originated from lengfu(冷敷), lengtie(冷貼), cold stone and cold water. Matching indications are various fever disease, skin diseases such as acute inflammation, wound, fever skin disease, otorhinolaryngological diseases such as acute sore throat, otitis, stomatitis, nasal bleeding and contusions, abrasions, burn and dysuria. In addition, it treats extremity coldness, chillness, stomachache caused to accumulate fever. 3. Physiotherapy by circulating meridian system is originated from manipulation such as pushing, massage and beating to therapy point. Matching indications are musculoskeletal diseases such as various muscular pain, heavy sensation, convulsion, urogenital diseases such as dysuria, lower abdomen pain, digestive tract diseases such as stomachache, and paralysis due to blocked meridian system. And other matching indications are psycosis, leprosy, hypoesthesia, acute stroke. In addition it helps other therapy methods. In addition, the power of manipulation classify to strengthen and reduce. 4. Physiotherapy by balancing meridian system is originated from sunshine, magnet, horn, bamboo and tube. Sunshine helps improving self's care and cure inflammatory skin disease. Magnet's matching indications are paralysis, various injuries, abscess, fever and eye disease. Cupping therapy treats to skin diseases and internal diseases such as tuberculosis. Conclusions : Traditional Korean medical physiotherapy was widely used in traditional Korean medicine since ancient time based on the traditional Korean medical principle and anatomical knowledge. With modern physiotherapy and traditional Korean medicine together, effects of treatment are enhanced. And traditional Korean medical physiotherapy is appropriated to world physiotherapy's expectation.

Evaluation of Engineering Characteristics and Utilization of Nonmetal Mining Waste Powder as Geo-Materials (비금속 광산 폐분의 공학적 특성 및 활용 가능성 분석)

  • Cho, Jinwoo;Lee, Yongsoo
    • Journal of the Korean GEO-environmental Society
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    • v.12 no.12
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    • pp.71-78
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    • 2011
  • This paper aims to present the evaluation of engineering characteristics and reusing possibility of waste powders produced in dolomite and limestone nonmetal mining by physical and mechanical experiments on compaction, uniaxial compressive strength, permeability, chemical composition, and so on. Granite soil, 2 types of limestone waste powder, and 1 type of dolomite waste powder were used for main materials, and cement and bentonite were used for admixed materials in this experiments. The findings based on the experimental results are the severe difference of chemical composition of the dolomite & limestone waste powder and the crushed rock waste powder, and the outstanding of engineering characteristics of the dolomite waste powder with high content of MgO compared with the limestone waste powder. The engineering properties on compaction, uniaxial compressive strength, and permeability are enhanced with increase of admixed ratio of waste powder on granite soil. From the experimental results, it can be suggested that the dolomite waste powder admixed with in-situ granite soil is useful as geo-materials with considering of distribution costs.

Interpretation of Firing Temperature and Material Similarity for Potteries from Ancient Tombs in Songpa Area, Seoul (서울 송파 지역 고분 출토 토기의 재료학적 동질성 및 소성온도 해석)

  • Lee, Gyu Hye;Yun, Jung Hyun;Lee, Chan Hee
    • Conservation Science in Museum
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    • v.28
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    • pp.17-34
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    • 2022
  • This study seeks to identify the material characteristics of earthenware excavated from the Bangi-dong Ancient Tomb No. 3 and the articulated stone-mound tomb of the Seokchon-dong ancient tombs in the Songpa region, and analyze the homogeneity and the firing temperature of the materials used at each excavated site. The remains have been studied relatively recently, and the groups of tombs in which they were found demonstrate the transition of ancient Korean burial systems, and at the same time, provide important archaeological data about those in power at the time. The earthenware pottery excavated from the two sites examined in the study were buried at different times, and it is assumed that they were made by procuring weathered soil of similar gneiss, judging from the behavior of the compatible and incompatible elements and the weathering tendency found by examining the main components. In addition, the examination of the mineral composition and microstructure of clay indicates that the earthenware from Seokchon-dong was fired at 950 degrees Celsius or lower at a relatively early stage. On the other hand, the earthenware from Bangi-dong Tomb No. 3 was confirmed to have experienced temperatures below 850 degrees Celsius and above 1,000 degrees Celsius. However, it is difficult to interpret the difference as the result of the changes in firing temperature throughout the eras. It is expected that it will be possible to interpret the changes in earthenware manufacturing techniques by comparing more diverse earthenware potteries and ancient soils.

The Change of Riverside Vegetation by Construction of Ecological Stream in Suwoncheon, Gyeonggi Province (경기도 수원천 생태하천 복원사업 이후 식생변화 연구)

  • Choe, Il-Hong;Han, Bong-Ho;Ki, Kyong-Seok
    • Korean Journal of Environment and Ecology
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    • v.24 no.6
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    • pp.723-734
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    • 2010
  • This study aims to analyze the change in vegetation for 10 years after the construction, targeting Suwoncheon, the first domestic ecological stream construction project. As for the section for the study, the section from Gyeonggi bridge to Youngyeon bridge, the first restoration project section, was targeted. The research districts consisted of 3 districts depending on topographical structure. Investigation check cosisted of cross-sectional topographical structure, vegetation status and the structure of herbaceous plant community. As for the cross-sectional topographical structure of the stream, the width of entire stream was 26.5~28.0m and water channel is 10~20m. The area for hydrophilic space was securing spacious riverside. Upper stream of reservoir beam was shallow and slow in reservoir area above weir. Lower stream of reservoir beam, the width of water channel was narrow and ripples were formed. Among species, 9 plants were planted and 6 species plants including Salix gracilistyla, Phragmites communis and Zoysia japonica were planted at the time of construction. In the water side, there were 2 species, such as Zoysia japonica and Trifolium repens, etc, still remained after seeding at the time of constrcution. The planted plants which were observed through this investigation, were 2 species such as Festuca arundinacea and Dactylis glomerata. Apart from the planted plants, arid climate herbaceous plant such as Setaria viridis and Artemisia princeps var. orientalis formed power and the naturalized species variously emerged in 15 species. For revetment, natural stone stacking method was condicted and Salix gracilistyla, Aceriphyllum rossii, etc were planted. But all the planted plants disappeared and now it was covered with Equisetum arvense and Humulus japonicus. It was because that the base for growth and development of the plants was not constructed at the time of restoration in a way of attaching natural stones onto the concrete base. In the water channel, various wetland species including Typha orientalis, Acorus calamus var. angustatus and Phragmites communis, etc, were planted but only Salix gracilistyla, Phragmites communis and Zizania latifolia remained. As for species of the autochthons, Persicaria thunbergii was dominant. In the lower stream of reservoir beam, Humulus japonicus formed forces. In the hydrophilic space, it was necessary to direct the landscape of in-stream vegetation in cosideration of users. For this, planting Miscanthus sacchariflorus in a community was proposed. In the upper stream of reservoir beam, suplementary screen seeding was necessary so that Zizania latifolia, Typha orientalis and Phragmites communis can fit the depth of water. In the Lower stream of reservoir beam, it was necessary to constantly manage Humulus japonicus so that the wetland autochthons species, such as Phragmites communis and Persicaria thunbergii can establish power more stably.

A Study on the Characteristics of Commemoration in the World War II Cemeteries - Focus on the Military Cemeteries of United States, the Commonwealth, and Germany in Western Europe - (제2차 세계대전 전쟁 묘지에 나타난 기념성 - 서유럽에 있는 미국군, 영연방군, 독일군 묘지를 대상으로 -)

  • Lee, Sang-Seok
    • Journal of the Korean Institute of Landscape Architecture
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    • v.49 no.5
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    • pp.97-111
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    • 2021
  • The purpose of this study was to analyze commemoration characteristics of the United States of America, the Commonwealth, and Germany through representative 14 military cemeteries of World war II in Western Europe. Based on the commemoration characteristics such as spacial characteristic, commemorative elements, and graves and headstone, the commemoration culture among U.S., the Commonwealth. and Germany were studied comparatively. The results are as follows. First, taking geometrical form with mainly square type, rarely circle and spiral patterned, most cemeteries were structured spatial central axis with symmetry, those cemeteries were styled neoclassical, but some of the U.S. cemeteries were modernistic, connecting spaces organically with curved line layout. Second, chapel, the wall of missing, the wall of battle map, and sculpture in the U.S military cemeteries, and 'the cross of sacrifice' and 'the stone of remembrance' as classical monument in the Commonwealth war cemeteries were commonly applied standardized commemorative elements, but commemorative monuments in German military cemeteries were restricted except monumental cross. Third, the symbolic cross of christianism was used all cemeteries to console and cherish the soul of soldiers, specially the Latin crosses in the U.S military cemeteries delivered political message as the american martyr for Western Europe and also the power of the U.S., but the cross in German and the Commonwealth war cemeteries were basically cherish and comfort individual spirit. Fourth, showing the power of victory with national patriotism, the U.S. strongly represented christianism and liberal democracy against communism, the Commonwealth showed imperialistic style, and German military cemeteries were quietly appeared as traditional style forwarding reconciliation and peace. This study suggest the war cemeteries have national identity with typical form and symbolic aesthetics. Further study will be required to materialize sublime commemoration in national cemeteries and to form advanced commemorative culture in Korea.

THE CURRENT STATUS OF BIOMEDICAL ENGINEERING IN THE USA

  • Webster, John G.
    • Proceedings of the KOSOMBE Conference
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    • v.1992 no.05
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    • pp.27-47
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    • 1992
  • Engineers have developed new instruments that aid in diagnosis and therapy Ultrasonic imaging has provided a nondamaging method of imaging internal organs. A complex transducer emits ultrasonic waves at many angles and reconstructs a map of internal anatomy and also velocities of blood in vessels. Fast computed tomography permits reconstruction of the 3-dimensional anatomy and perfusion of the heart at 20-Hz rates. Positron emission tomography uses certain isotopes that produce positrons that react with electrons to simultaneously emit two gamma rays in opposite directions. It locates the region of origin by using a ring of discrete scintillation detectors, each in electronic coincidence with an opposing detector. In magnetic resonance imaging, the patient is placed in a very strong magnetic field. The precessing of the hydrogen atoms is perturbed by an interrogating field to yield two-dimensional images of soft tissue having exceptional clarity. As an alternative to radiology image processing, film archiving, and retrieval, picture archiving and communication systems (PACS) are being implemented. Images from computed radiography, magnetic resonance imaging (MRI), nuclear medicine, and ultrasound are digitized, transmitted, and stored in computers for retrieval at distributed work stations. In electrical impedance tomography, electrodes are placed around the thorax. 50-kHz current is injected between two electrodes and voltages are measured on all other electrodes. A computer processes the data to yield an image of the resistivity of a 2-dimensional slice of the thorax. During fetal monitoring, a corkscrew electrode is screwed into the fetal scalp to measure the fetal electrocardiogram. Correlations with uterine contractions yield information on the status of the fetus during delivery To measure cardiac output by thermodilution, cold saline is injected into the right atrium. A thermistor in the right pulmonary artery yields temperature measurements, from which we can calculate cardiac output. In impedance cardiography, we measure the changes in electrical impedance as the heart ejects blood into the arteries. Motion artifacts are large, so signal averaging is useful during monitoring. An intraarterial blood gas monitoring system permits monitoring in real time. Light is sent down optical fibers inserted into the radial artery, where it is absorbed by dyes, which reemit the light at a different wavelength. The emitted light travels up optical fibers where an external instrument determines O2, CO2, and pH. Therapeutic devices include the electrosurgical unit. A high-frequency electric arc is drawn between the knife and the tissue. The arc cuts and the heat coagulates, thus preventing blood loss. Hyperthermia has demonstrated antitumor effects in patients in whom all conventional modes of therapy have failed. Methods of raising tumor temperature include focused ultrasound, radio-frequency power through needles, or microwaves. When the heart stops pumping, we use the defibrillator to restore normal pumping. A brief, high-current pulse through the heart synchronizes all cardiac fibers to restore normal rhythm. When the cardiac rhythm is too slow, we implant the cardiac pacemaker. An electrode within the heart stimulates the cardiac muscle to contract at the normal rate. When the cardiac valves are narrowed or leak, we implant an artificial valve. Silicone rubber and Teflon are used for biocompatibility. Artificial hearts powered by pneumatic hoses have been implanted in humans. However, the quality of life gradually degrades, and death ensues. When kidney stones develop, lithotripsy is used. A spark creates a pressure wave, which is focused on the stone and fragments it. The pieces pass out normally. When kidneys fail, the blood is cleansed during hemodialysis. Urea passes through a porous membrane to a dialysate bath to lower its concentration in the blood. The blind are able to read by scanning the Optacon with their fingertips. A camera scans letters and converts them to an array of vibrating pins. The deaf are able to hear using a cochlear implant. A microphone detects sound and divides it into frequency bands. 22 electrodes within the cochlea stimulate the acoustic the acoustic nerve to provide sound patterns. For those who have lost muscle function in the limbs, researchers are implanting electrodes to stimulate the muscle. Sensors in the legs and arms feed back signals to a computer that coordinates the stimulators to provide limb motion. For those with high spinal cord injury, a puff and sip switch can control a computer and permit the disabled person operate the computer and communicate with the outside world.

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