• Title/Summary/Keyword: Natural Standard

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Performance Evaluation of Recycled Aggregate Concrete Made of Recycled Aggregate Modified by Carbonation (탄산화 개질 순환 골재를 사용한 순환 골재 콘크리트의 성능 평가)

  • Ha, Jung-Soo;Shin, Jin-Hak;Chung, Lan;Kim, Han-Sic
    • Journal of the Korea Concrete Institute
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    • v.28 no.4
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    • pp.445-454
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    • 2016
  • With the increase of decrepit facilities, construction waste increased to a certain level and now the increase is more or less stabilized. Yet construction waste still constitutes the largest portion of the overall wastes. Also, it is inevitable to spend a huge amount of the national budget due to the aggravating shortage of aggregate caused by prohibition on collection of natural aggregates as well as due to the damage to the land and environment caused by development of the sources of aggregates. As a countermeasure to the situation, the Ministry of Land, Infrastructure and Transport promulgated the quality standard for recycled aggregate to manage the usage of recycled aggregate according to its quality. But use of recycled aggregate for the purpose of high added value still remains nominal. Therefore, this research aims to study the applicability of recycled aggregate concrete as structural concrete by evaluating the quality improvement effects and the performance of the recycled aggregate concrete including recycled fine aggregate and recycled coarse aggregate that have undergone carbonation for 4 days and 14 days respectively in the condition of 60% RH, 20% $CO_2$ and $20^{\circ}C$ temperature, suggested for carbonation modifying from the advance research. The result shows carbonation modify contributed to quality improvement with 0.91% decrease in absorption rate for recycled fine aggregate and 0.7% decrease in absorption rate for recycled coarse aggregate. The physical properties and durability of the recycled aggregate made of aggregate modified by carbonation showed results similar to general concrete, which confirmed the possibility of applying the recycled aggregate made of recycled aggregate modified by carbonation to structural concrete.

Analysis of Fundamental Properties of Concrete Using Mix of Coarse Aggregate With Formation Causes (성인이 다른 굵은 골재를 혼합사용한 콘크리트의 기초적 특성 분석)

  • Noh, Sang-Kyun;Kim, Young-Hee;Kim, Jeong-Bin;Han, Cheon-Goo
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.3 no.1
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    • pp.15-21
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    • 2015
  • Recently, attempts of replacing some of natural aggregate with mix of low quality aggregate are carried out for stable supply of aggregate. However, low quality aggregate such as recycled aggregate produced during the disposal process of construction wastes and by-product aggregate produced by industrial activities has problem of failing to comply to KS Standards. Therefore, we have compared fundamental properties of concrete by using granite crushed aggregate, recycled aggregate, blast furnace and electric arc furnace slag aggregate for effective utilization of lacking aggregate resources. As the result, slump in case of mixed use of aggregate was increased 0~10% compared to single use. Therefore, it is judged to be economically advantageous as it can expect effects in unit quantity or reduction of SP agent. Compressive strength in case of mixed use of aggregate was increased 0~10% compared to single use as it filled internal crevice of concrete with continuous particle size distribution. Accordingly, if we utilize by satisfying standard particle scope through mix of aggregate with different cause of formation in proper ratio, it was possible to confirm utility of mixed aggregate with demonstration of effects of increases of fluidity and compressive strength of concrete.

Studies on the Reference Korean and Estimation of Radiation Exposure Dose - PHYSICAL STANDARD AND ESTIMATION OF INTER-EXTERNAL RADIATION EXPOSURE DOSE - (표준한국인(標準韓國人)의 최대허용(最大許容) 피폭선량(被曝線量) 설정(設定)에 관한 연구(硏究) - 체위(體位) 및 내(內).외부(外部) 피폭선량(被曝線量) 추정(推定) -)

  • Kim, Yung-J.;Lee, Kang-S.;Chun, Ki-J.;Kim, Jong-B.;Chung, Gook-H.;Kim, Sam-R.
    • Journal of Radiation Protection and Research
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    • v.7 no.1
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    • pp.1-10
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    • 1982
  • For the purpose of establishment of Reference Korean and estimation of internal and external exposure doses in the Reference Korean, we have surveyed reference values for Koreans, such as physical standards including height, weight and body surface area, food consumption rate of daily intake of radioactive substances and exposure dose from natural radiation. The results obtained are as follows: 1) The age group of the Reference Korean ranged from 20 to 30 years old in both sexes. The height, weight and surface area of the body of the Reference Korean are 167cm, 61kg and $1.67m^2$ in male and 155cm, 51kg and $1.51m^2$, respectively in female. 2) The food consumption of the Korean is 812.8g (669.6g of vegetable food and 143.2g of animal food) per capita per day. 3) Koreans are taken about 1,200 pCi of radioactive substances(${\beta}$-ray) per capita per day. 4) The external and internal radiation exposure doses of the Korean are estimated to be 127 mrem and 8 mrem per year, respectively. However, it is believed that these values will be modified upon the addition of data collection.

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『Bonchojeonghwa(本草精華)』, Medical Historical Approach to Bibliographic Notes (『본초정화(本草精華)』의 해제(解題)에 관한 역사학적(醫史學的) 접근)

  • Kim, Hong-Kyoon
    • The Journal of Korean Medical History
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    • v.24 no.2
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    • pp.25-55
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    • 2011
  • The currently existing "Bonchojeonghwa (本草精華)" is a manuscript without the preface and the epilogue, composed of 2 books in 2 volumes. This book is a quintessence of knowledge on science of medicinal ingredients (medicinal phytology I herbal science) as well as an trial of new development in Chosun medical science. I.e. this book includes surprising change representing medical science in Chosun dynasty as a single publication on science of medicinal ingredients. It holds a value essential to clinician as a specialized book in medicinal ingredients, and Includes richer content on medicinal ingredients than any other books published before. In addition, it is away from boring list-up of superfluous knowledge as seen in "Bonchokangmok(本草綱目)" published in China, and well summarizes essential knowledge which can be used within a range of medicines available in Korea. This book has an outstanding structure that can be even used in today's textbook on science of medicinal ingredients, as it has clear theory, system and classification. Because it handles essential learning points prior to prescription to disease, it is possible to configure new prescription and adjustment of medicinal materials. Moreover, this book can play a good role for linguistic study at the time of publication, because it describes many drugs in Hangul in many parts of the book. "Bonchojeonghwa" includes a variety of animals, plants and mineral resources in Korea, like "Bonchokangmok" which was recently listed in UNESCO. As such, it has a significance in natural history as well as pharmacy in Korean Medicine. It has various academic relationships all in biologic & abiologic aspects. It has importance in sharing future biological resources, building up international potential, setting up the standard for biologic species under IMF system, and becoming a base for resource diplomacy. We should not only see it as a book on medicinal ingredients in terms of Oriental Medicine, but also make an prudent approach to it in terms of study strengthening Korea's national competitiveness. After bibliographical reviewing on the features & characteristics of the only existing copy of "Bonchojeonghwa" housed in Kyujanggak(奎章閣) of Seoul National University, the followings are noted. First, "Bonchojeonghwa" is a specialized book on medicinal ingredients voluntarily made by private hands to distribute knowledge on drugs in the desolate situation after Imjinoeran (Japanese Invasion in 1592), without waiting for governmental help. Second, it raised accessibility and practicality by new editing. Third, it classified 990 different kinds of drugs into plant, animal, and mineral at large, and dassified more in detail into 15 'Bu' and 48 'Ryu' at 258 pages. Fourth, the publication of this book is estimated to be around 1625~1633, at the time of Injo's reign in 17th century. Fifth, it contains the existing & up-to-date knowledge at the time of publication, and it is possible to see the supply-demand situation by Hangul descriptions in 149 places in the book. By the fact that there are many linguistic evidences of 17th century, explains well when the book was published.

The Distribution of Vascular Plants Recorded in the Hangul Tripitaka (한글대장경에 기록된 관속식물의 분포)

  • Park, Hee-Jun;Paik, Weon-Ki
    • Korean Journal of Plant Resources
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    • v.27 no.5
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    • pp.576-587
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    • 2014
  • The purpose of this research is to classify various plants written in the Korean Buddhist scriptures and assign scientific name to them in accordance with the Hangul Tripitaca as standard scriptures, thereby establishing the foundation of the plants in Buddhist scriptures. As a natural resource, we also assessed the value of the plants written in the Buddhist scriptures that distributed from other countries. To this end, we inferred the route of introduction to Korea of the plants and investigated their function and usage. Taxonomic classification of the plants written in Buddhist scriptures identified a total of 331 taxa belonging to 107 families, 244 genera, 313 species, 1 subspecies, 16 varieties, 1 forms. Species composition of the 331 taxa of plants consisted of two taxa of pteridophyte, 15 taxa of gymnosperm, 261 taxa of dicotyledon, and 53 taxa of monocotyledon. Among them, 183 and 148 were woody and herbaceous plants, respectively. Analysis of the distribution of 331 kinds of plants that India's portion of origin of place is 8.9% which holds a low rank compared with those of Korea (10.5%), China (10.9%), and Japan (10.0%). This explains why many taxa of plants distributed from the three countries appeared in the Hangul Tripitaca. Accordingly, we hypothesized that the majority of the plants were added and replaced at some point in past while Buddhist scriptures were propagated from India to China and from China to Korea. Our analysis indicated that 119 out of the 331 taxa (36 %) were distributed from Korea.

The Shape and the Location of Forehead Hairline of Korean Males in Their 20s & 30s (20, 30대 한국 남성의 전두부 모발선의 모양과 위치)

  • Yoon, Sung-Won;Kim, Chung-Hun
    • Archives of Plastic Surgery
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    • v.38 no.3
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    • pp.295-299
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    • 2011
  • Purpose: It is generally believed that alopecia is caused by various factors such as scars, stress, genetical factors, androgens, etc. Androgenic alopecia is one of the most common cause of alopecia and found mainly in males. Propecia (Merck & Co., USA) and Minoxidil (McNEIL-PPC, Inc, USA) were the drugs approved from FDA for treatment of androgenic alopecia. Surgical treatments such as flap, tissue expansion, scalp reduction and hair transplantation can be considered if necessary. Hair micrograft techniques were developed for natural hair shapes and minimal adverse effect. There were attempts to measure the length of the forehead of the Korean young adults. However attempts to classify the shape and location of forehead hairline were rare. This study attempted to find out standard hairlines of young adults in their 20s & 30s and the result would be the guideline of the hairline in hair replacement surgery of male patients in their 40s & 50s. Methods: 200 male adults in 20s and 30s were photographed and measured the length of 11 vertical index lines to determine hairline. The indexes are the distances from hairline to intercanthal midpoint (A), to medial canthus (B), to upper eyelid fissure (C), to lower eyelid fissure (D), to lateral canthus (E) and distance from lateral highest point to medial lowest point, if the hairline is M-shape (F). Additionally, we classified the hairlines into 4 groups, M, horizontal, inverted U and irregular shapes. Results: The most common hairline of male adults in their 20s is inverted U-shape (53.3%), followed by horizontal-shape, M-shape, irregular-shape. In their 30s, inverted U-shape (59%) is followed by irregular-shape, M-shape, horizontal-shape. The M-shape is more frequently found in males in 30s than those in 20s. The mean values of the indexes in their 20s are as follows: A (76.14 mm), B (Rt: 75.78 mm, Lt:76.41 mm), C (Rt: 69.43 mm, Lt: 69.92 mm), D (Rt: 76.92 mm, Lt:77.46 mm), E (Rt: 64.16 mm, Lt: 64.73 mm), F (4.09 mm). Those in their 30s are as follows: A (76.13 mm), B (Rt: 76.114 mm, Lt: 76.02 mm), C (Rt: 69.87 mm, Lt: 70.37 mm), D (Rt: 77.37 mm, Lt: 77.58 mm), E (Rt: 69.63 mm, Lt: 69.85 mm), F (6.14 mm). Conclusion: The knowledge about human body measurement is indispensable to plastic surgeons. In this study, inverted U shape is the most common type of hairline in 30s, and similar distribution is found in 20s. The percentage of M shape in their 30s is elevated more than 10% compared to that in their 20s. The study of hairline shapes and 11 indexes of hairlines can be useful for planning of the hair transplantation and postoperative evaluation. This study being based on photogrammetry, there may be differences between actual distance of curved face and projected distance on flat photographs.

Rapid Diagnosis of Resistance to Glufosinate-ammonium in Transgenic Sweet Potato (형질전환 고구마에 대한 Glufosinate-ammonium 저항성 간이진단법)

  • Kuk, Yong-In
    • Korean Journal of Weed Science
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    • v.30 no.4
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    • pp.380-389
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    • 2010
  • Transgenic herbicide-resistant sweet potato plants [Ipomoea batatas (L.) Lam.] produced through a biolistic transformation were used in this study. The objective of this research was to find out a rapid and reliable assay method for confirming glufosinate-ammonium resistance. The techniques tested include whole-plant bioassay, one leaf bioassay, and leaf disk bioassay. Parameters investigated in this study were leaf injury and ammonium accumulation at 1 and 5 days after treatment of glufosinate-ammonium. In the leaf disk bioassay, leaf injury of the transgenic line 7171 was 1.9-fold less affected by glufosinate-ammonium than the wild type. The leaf injury of 7171 in one leaf and whole-plant bioassays was 59- and 92-fold less affected by glufosinate-ammonium, respectively, compared with that of the wild type. Leaf disk, one leaf, and whole-plant bioassays showed that ammonium accumulation of the 7171 was 2 to 20-, 4 to 43-, and 6 to 115-fold less affected by 0.5-5 mM glufosinate-ammonium than that of the wild type. All three bioassays successfully distinguished the resistance from the transgenic lines, but one leaf bioassay is the simplest and quickest. Leaf injury and ammonium accumulation were the same in leaves 1, 3, 5, 7, and 10 of 3 mM glufosinate-ammonium treated plants or nontreated plants. The one leaf bioassay was chosen as the standard procedure for future confirmation of resistance in transgenic sweet potato because it is a rapid and reliable assay.

Early Life History of Black Bullhead, Pseudobagrus koreanus(Pisces, Bagridae), from Kum River, Korea (금강에 서식하는 눈동자개 Pseudobagrus koreanus(Pisces, Bagridae)의 초기 생활사)

  • Kang, Eon-Jong
    • Korean Journal of Ichthyology
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    • v.10 no.2
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    • pp.184-190
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    • 1998
  • The early life history of black bullhead, Pseudobagrus koreanus, endemic to Korea was investigated to get biological information needed in artificial production of seedlings and in recovering natural resources. The fertilized eggs showed some characteristics in having heavy sticky material and minute folds which is formed radical pattern on the egg membrane. The shape of egg was spherical and $2.59{\pm}0.08$(2.45~2.70, n=10)mm in diameter. The yolk had not oil globule. The first cleavage was observed 2 hrs after insemination at $21{\sim}23^{\circ}C$, and the progressive cleavage were done about 30 min. interval. The characteristic changing of the yolk surface started at morula stage and continued to the end of gastrula. Hatching was started 72 hrs and completed 90 hrs after fertilization. The size of the larvae were 5.41~5.81mm in total length and 2.76~2.94mm in preanal length, and the number of so mites was 15-16+33~34(48~50). The barbels and swimbladder were completed and all the fins except second dorsal were appeared 1 week after hatching. The larvae attained 9.67~10.52mm in total length and 5.20~5.65mm in preanal length. All the fin sets and color pattern were completed 2 weeks after hatching and body mucus was secreted at that stage. The juvenile attained 14.59~16.02mm in standard length, 3.31~4.16mm in head length and 8.07~9.31mm in prenal length.

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Method of a Multi-mode Low Rate Speech Coder Using a Transient Coding at the Rate of 2.4 kbit/s (전이구간 부호화를 이용한 2.4 kbit/s 다중모드 음성 부호화 방법)

  • Ahn Yeong-uk;Kim Jong-hak;Lee Insung;Kwon Oh-ju;Bae Mun-Kwan
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.42 no.2 s.302
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    • pp.131-142
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    • 2005
  • The low rate speech coders under 4 kbit/s are based on sinusoidal transform coding (STC) or multiband excitation (MBE). Since the harmonic coders are not efficient to reconstruct the transient segments of speech signals such as onsets, offsets, non-periodic signals, etc, the coders do not provide a natural speech quality. This paper proposes method of a efficient transient model :d a multi-mode low rate coder at 2.4 kbit/s that uses harmonic model for the voiced speech, stochastic model for the unvoiced speech and a model using aperiodic pulse location tracking (APPT) for the transient segments, respectively. The APPT utilizes the harmonic model. The proposed method uses different models depending on the characteristics of LPC residual signals. In addition, it can combine synthesized excitation in CELP coding at time domain with that in harmonic coding at frequency domain efficiently. The proposed coder shows a better speech quality than 2.4 kbit/s version of the mixed excitation linear prediction (MELP) coder that is a U.S. Federal Standard for speech coder.

The Effects of Timber Harvesting on Soil Chemical Ingredients and Stream Water Quality (성숙임목수확벌채가 토양의 화학성분과 계류수질에 미치는 영향)

  • 박재현;우보명;김우룡;안현철;김재수
    • The Korean Journal of Ecology
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    • v.23 no.1
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    • pp.9-15
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    • 2000
  • The effects of clearcutting on soil chemical ingredients and stream water quality have been investigated at a natural deciduous forest catchment within the Seoul National University Research Forest in Mt. Paekun, Chunnam province during the periods of 1993 to 1998. Soil chemical ingredients and stream water qualities were monitored at a 13 ha clearcutting site and a non-treatment site nearby. During the first and second years after harvesting, the levels of total-N, and exchangeable ions (K/sup +/, Na/sup +/, Ca/sup 2+/, Mg/sup 2+/) decreased compared to the values of before harvesting. During the fifth years after harvesting, these levels were significantly higher than those during the first and second years after harvesting. But the chemical characteristics of soil were not changed at all. pH of water in the harvesting area was 6.5 in stream water. Among the nutrients, Cd, Pb, Cu, and phosphate were not found, and the level of BOD reached at the level of the domestic use suitable for drinking. Turbidity, odor, taste, NH/sub 4//sup +/ -N, NO/sub 3//sup -/-N, standard plate count, and coliform were also low enough to be used as the domestic use for drinking by the near villagers. During the first and second years after harvesting, BOD increased to about 1 ppm. For that reason, the harvesting planning should be built in the harvesting area in consideration of the control of water quality in the stream.

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