• Title/Summary/Keyword: Sickle

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An Ecological Approach to Nutritional Research (영양학 연구의 생택학적 접근)

  • 문수재
    • Journal of Nutrition and Health
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    • v.34 no.1
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    • pp.98-111
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    • 2001
  • The article demonstrates a method of studying human health and nutrition by applying a multi-disciplinary approach and examines how humans developed and survived by adjusting to their environment. This process involves physiological, cultural and genetic adaptation both independently and interactively. This study postulates that a sound human health may be the result of balance between nutrition and environmental conditions. It is noted that there is a positive correlation between malaria and fava bean intake, and sickle cell anemia and cassava intake. It is also suggested that the difference in disease structure in soybean and non-soybean consumption cultures can be explained by an ecological approach to studying nutrition. This study further suggest that the relationship between nutrition and socio-cultural system. epidmiological study of nutrition and cultural environment nutrition and conceptual characteristics, nutrition and food intake pattern, nutrition and health sociological functions and the physioloical, cultural and genetic adaptation can all be stimulating research subjects to be studied form and ecological point of view. This article also includes the results from a series of ecological studies conducted by the author investigating the relationship between nutritional status of Korean breast-feeding mothers and the composition of the human milk and also the Vitamin D status of Korean and their lifestyle. (Korean J Nutrition 34(1):98-111, 2001)

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Mycological Characteristics and Pathogenicity of Fusarium oxysporum Schlecht. emend. Snyld. & Hans. Causing Stem Rot of Cactus (접목선인장 줄기썩음병균, Fusarium oxysporum Schlecth. emend. Snyd. & Hans.의 균학적 특성과 병원성)

  • 현익화;이상덕;이영희;허노열
    • Korean Journal Plant Pathology
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    • v.14 no.5
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    • pp.463-466
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    • 1998
  • A Fusarium species was isolated from stems of cactus(Hylocereus trigonus) showing rot symptoms at Koyang, Kyonggi province in 1997. This pathogen was identified as Fusarium oxysporum based on mycological characteristics. The rot symptom appeared at the soil line and roughly circular lesions, 1∼3 mm in diameter, appeared on basal stems. The pathogen formed both microconidia and macroconidia. Microconidia were formed abundantly in false-heads on short monophialides, oval to kidney-shaped. Macroconidia were slightly sickle-shaped, 3∼5-septated with an attenuated apical cell and a foot-shaped basal cell. Colony color on PDA was white, peach or purple. Chlamydospores were formed abundantly on PDA. The pathogen was able to cause stem rot symptoms to cactus by wound inoculation as well as non-wound inoculation.

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Fine Structural Observations on Spermatogenesis of the Goldeye Rockfish, Sebastes thompsoni (Teleostei: Scorpaenidae)

  • LEE Jung Sick;OH Yung Keun;HUH Sung-Hoi
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.6
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    • pp.1005-1012
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    • 1997
  • Fine structural changes of the germ cells during spermatogenesis in the goldeye rockfish, Sebastes thompson; were examined by means of the transmission and scanning electron microscopy. A spermatogonium has a large nucleus with a single nucleolus in the interphase. Primary spermatocytes are characterized by the formation of chromatin clumps and presence of the synaptonemal complex in the nucleus. The nucleoplasm of secondary spermatocytes is more condensed than that of primary spermatocytes, and the cytoplasm contains numerous mitochondria, endoplasmic reticulum and Golgi complex. The nuclei of spermatids in metamorphosis show sickle-like shape as the nucleoplasm becomes more condensed. In the cytoplasm of spermatids, the proacrosomal granules are not found at all. A spermatozoon consists of head, neck and tail. The acrosome is absent in the head. Four to five cytoplasmic collars are observed in the posterior portion of the head of spermatozoon. The well developed axonemal lateral fins are observed in the flagellum of spermatozoon.

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Material Characteristics and Provenance Presumption for Stone Artifacts of Bronze Age from the Hyocheon Site in Gwangju, Korea (광주 효천유적 출토 청동기시대 석기의 재질특성과 원산지 추정)

  • Park, Sung-Mi;Lee, Chan-Hee;Kim, Ji-Young;Jeong, Il
    • Journal of Conservation Science
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    • v.21
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    • pp.5-20
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    • 2007
  • The stone artifacts in Bronze age from the Hyocheon sites in the Gwangju, Korea were studied on the basis of material characteristics and provenance presumptions. The use and rock names of the artifacts are a stone shovel by andesite, the stone grinding pestle by pyrophyllite, the stone sickle by schist and four stone semifinished artifacts by slates. Andesitic stone shovel could be observed easily around the Hyocheon relic site. But, rocks of the stone grinding pestle, the stone sickle, the stone arrowhead and the stone semifinished artifacts could be confirmed typical occurrences of the all kinds of rocks around the Hwasun coal mine area above 10km from the site. These are made the coupled samples with each stone artifact to the same kinds of raw material rocks based on analysis of the lithology and geochemistry. As a result a geochemical evolution trends of both a stone artifact and the rock showed very similar patterns based on normalization using the behavior, enrichment, compatibility and incompatibility of the elements. Therefore, the source rock of the stone shovel was convey from Mudeung mountain possible interpreted that the domestic-type artifacts are distributed in the vicinity of the Hyocheon site. On the other hand, the stone grinding pestle, the stone sickle, the stone arrowhead and the stone semifinished artifacts were convey from the Hwasun coal mine area possible foreign-type stone artifacts interpreted that the source rocks. Consequently, in the foreign-type stone artifacts are should archaeologic research which it can examine various possibilities clearly that the possibility to coming the introduction with the mankind migration, diffusion to dealings of tribe, the captured enemy equipment through the war and the trade with the behavior of the materials.

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Metallurgical Study on the Iron Artifacts Excavated from Sudang-ri Site in Geumsan (금산 수당리유적 출토 철제유물의 금속학적 연구)

  • Park, Hyung-ho;Cho, Nam-chul;Lee, Hun
    • Korean Journal of Heritage: History & Science
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    • v.46 no.3
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    • pp.134-149
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    • 2013
  • The Sudang-ri Site in Geumsan is considered the historic site where Baekje dominated the inland traffic route to Gaya through Geumsan and Jinan in the 5th Century. This study identified the production techniques of iron by conducting an analysis of metallographical microstructure of the artifacts such as an iron sword and an iron sickle that were excavated in Sudang-ri Site, Geumsan, one of the regions ruled by Baekje, and tried to figure out the characteristics and the technical systems of Baekje's ironmaking around the 5th Century by comparing them with other iron artifacts produced around the same time. The analysis showed that various production techniques were applied to the artifacts excavated in Sudang-ri Site, Geumsan. Depending on the production techniques, they can be divided largely into three methods: the simple shape-forging method, the steel manufacture method after forging, and the steel manufacture & heat-treatment method after forging. The iron sickle from the stone chamber tomb No. 1, which was produced only through forging, is mostly composed of soft ferrite at both edges of the blade and at the rear making the use of the weapon impractical. From this fact, it is presumed that they were produced as burial objects or ceremonial accessories for the person buried. The iron axe from the outer stone coffin tomb No. 1 and the iron swords and sickle from the outer stone coffin tomb No. 12, which were produced through the steel manufacture method after forging such as carburizing, did not go through the heat treatment such as quenching, but applied different production processes to each part. Therefore, it is deemed that they were produced as daily tools for cultivation rather than burial objects or ceremonial accessories. The production techniques following the forging process - carburizing and heat treatment - can be found on the iron swords from the outer stone coffin tomb No. 5 and the outer stone coffin tomb No. 12. The sturdy structure of the blade part and the durable structure of the rear processed with heat are deemed to have been produced as weaponry and used by the person buried. Based on the analysis of the iron artifacts excavated from Sudang-ri Site in Geumsan, the characteristics of iron production techniques were investigated by comparing them with the artifacts from Yongwon-ri Site in Cheonan, Bongseon-ri Site in Seocheon, and Bujang-ri Site in Seosan that were made around the same time as the cluster of Baekje tombs examined by the metallographical microstructure analysis of this study. For the iron artifacts analyzed here, the changes in the techniques were investigated using the iron swords common in all of the tombs. In the case of the iron swords, it was identified the heat treatment technique called tempering was applied from the 4th Century.

A study on the oral prophylaxis subject satisfaction of the dental hygiene department students in some area (일부 치위생과 학생들의 치면세마교과목 만족도에 관한 연구)

  • Shim, Hyung-Soon;Lee, Hyang-Nim
    • Journal of Korean society of Dental Hygiene
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    • v.9 no.1
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    • pp.15-26
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    • 2009
  • The purpose of this study was to prepare improved education guideline by grasping parts and items felt difficult to apply instruments by the students of the dental hygiene department in the practice of oral prophylaxis using manikin and analyzing factors influencing the satisfaction at the oral prophylaxis subject. To achieve this purpose, 285 senior students of the dental hygiene department located in the Kwangju. Jeonnam area who took theory and practice courses of oral prophylaxis but only practiced the manikin from the second semester of 1st year were selected as the subjects. The following results were obtained. 1. In the manikin, the most difficult part was maxillary anterior lingual in the use of explorer, sickle scaler, and universal curet, and maxillary right posterior lingual was in the use of gracey curet. In the dentiform, the most difficult item was instrument stroke in the use of explorer, sickle scaler, universal curet and gracey curet. 2. The highest stressor was the lack of knowledge and skill in practice of oral prophylaxis, followed by the lack of confidence, and difference between theory and practice in oral prophylaxis. The overall practice satisfaction was 3.23 at oral prophylaxis. The highest satisfaction was found in patient and operator position(3.51), followed by basic skill(3.34), the way to use hand instrumentation(3.16), and the way to use oral examination instrumentation(3.01). 3. According to school records, satisfaction at oral prophylaxis practice satisfaction was 3.36 of good, 3.24 of fair, and 3.06 of poor, suggesting significant difference(p<0.05). Students who participated just in practice during a school term showed 3.47 of satisfaction. The highest satisfaction was found in a full-time professor as a professor in charge(3.24) and there was significant difference(p<0.05). 4. The highest correlated factor between oral prophylaxis theory and practice satisfaction was curriculum satisfaction. The use of hand instrumentation was found to have the greatest effect on the practice satisfaction at oral prophylaxis, followed by basic skill, the way of basic instrumentation, and position. There was statistically significant difference(p<0.01).

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A Study on the Design of Rotary Mower and Its Utilization. (Rotary Mower의 제작과 그 이용에 관한 연구)

  • 최규홍
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.17 no.4
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    • pp.3897-3920
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    • 1975
  • Since the most of Korean dairy and cattle raising farms are too small to introduce western mechanized farming, it is necessary to develope small size equipments. This study has been carried to develop a rotary mower as on attachment of 8 to 10 horse powertiller which is widely spread in rural area. It will not ony be helpfull for the farmers to harvesting hay grass but also desirable to increase the power tiller utility. The protto type rotary mower designed through the fundamental investigations, has been modified and improved through the field trials, and a series of field tests has been carried to investigate its performance and economic feasibility comparing with existing vailable harvesting equipments. The results are as follows; 1. To increase the stability, two guide wheels are attached to both side of the protto type rotary mower. 2. To prevent the clinging of tall grasses, the vertical driving shafts are covered with cylindrical protectors. 3. The cutting height is adjustable in 8 steps from 2.5 to 20 centimeters by changing the length of guide wheel legs. 4. The practical Critical cutting speed were always higher than theoretical value in both case of single cutting blade and three when the cutting depth was 25 millimeter. 5. The peripheral speed of cutting blade was varied in response to the change of engine speed, mean while the peripheral speed was adequate as it was changhed from 25 to 35 meter per second when the power tiller is operated in proper working ground speed. 6. The time requirement to harvest 10 a were 88.7, 54.6 and 41.4 minutes for the first, second and third stage of ground speed respectively, and because of the difficulty of delivery, it was observed that operating with fourth stage of ground speed was not recomanendable when the grass height is taller than 90 centimeters. 7. The performance of rotary mower were 1.1-1.7, 1.4-4.0, 3.8-11.8 and 7.4-22.0 times of reciprocating mower, portable disc type cutter, hay scythe and ordinary sickle respectively. 8. When the slope exceeds, 20 degree the downward harvesting operation was impossible because of the excessive front end weight, while less than 5 degree of land slope did not effect in field operation. 9. Increased traveling spee caused higher cutting height and slight cutting failure, but seems not to effect to the gross yield, and the efficiency of cutting width were from 83 to 94 precent. 10. Tn rank of economy were rotary mower (3,2 stage operation), reciprocating mower, hay scythe, portable disc type cutter and sickle in order when the annul operation exdeeds 100 hours. From the above results, it is convinced that the protto type rotary mower is good enough to the livestock farmers as a hay harvesting equipment because of its economy, hardiness in operating and its out standing performance and hopefully it will contribute to the extension of Korean livestock farming.

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First Reliable Record of the Sickle pomfret, Taractichthys steindachneri (Bramidae: Perciformes) from Korea (우리나라 남해에서 출현한 새다래과(농어목) 한국미기록종, 흰꼬리타락치 Taractichthys steindachneri)

  • Kim, Byung-Jik;Kim, Jin-Koo;Ryu, Jung-Hwa;Park, Ji-Tae
    • Korean Journal of Ichthyology
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    • v.24 no.3
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    • pp.230-233
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    • 2012
  • Taractichthys steindachneri is described based on two specimens (224.7~406.5 mm SL) collected from the south sea including the adjacent water of Jeju Island, representing a reliable first record from Korea. The species is characterized by having well-separated each pelvic fin, semicircular groove on dorsal surface of caudal peduncle, well-elongated dorsal and anal fin rays, nearly uniformly blackish body color with white margined caudal fin.

A Study on the Door Discovered at the Shinchang-dong Wetland Site (광주(光州) 신창동(新昌洞) 저습지출토(低濕地出土) 나무문짝(비문(扉門))에 관한 연구(硏究))

  • Cheon, Deuk-Youm;Shin, Sang-Hyo
    • Journal of architectural history
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    • v.15 no.5
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    • pp.7-18
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    • 2006
  • A lot of relics were unearthed in the Shinchang-dong wetland site, which can help restore prehistoric life style, including construction tools such as wood doors, wood hammers, ax handgrips, sickle handgrips, wedges, awls, wood pillars and connection members, food vessels made of earth or wood and fish, shell fish, seeds and remains of weapons. In particular, a door was found in the site, which was measured at 110cm long and 37cm wide. If restored it will be 75cm wide. The door seems to date back as far as the 1st century B. C., which would be the oldest one ever discovered in Korea. This paper is intended to explore the implications of the door by investigating the environment of the Shinchang-dong wetland site bearing the relics intact, manufacturing techniques and times of manufacturing of the door as well as attributes of doors presented in the literature related to old time architecture such as Goguryeo tomb paintings and house-shaped vessels. It also intends to provide basic data for study of residential architecture in prehistoric times.

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The Design and Development of An Oil Palm Fresh Fruit Bunch Cutting Device

  • Ahmad, Desa
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1996.06c
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    • pp.458-468
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    • 1996
  • The Oil Palm industry has developed tremendously with the increasing of planted area from 54,000 hectaresin 1960 to about 2.28 million hectares in 1995. This is expected to increase further to 2.5 million hectares by the year 2000. However, there has been an increasing difficulty in obtaining sufficient labour for the oil palm plantations. At present , harvesting of oil palm fresh fruit is facing an acute shortage of workforce as the workers are much more attracted to the better working environment and salary in the industrial sector. Harvesting of short palm is easily done by using a chisel attached to a short steel pole. Cutting is done by moving the tool at high speed to the target. The weight of the tool coupled with the speed of throwing will produce enough energy to cut the bunch stalk. In this cutting method, sharpness of the cutting device, weight of tool and the speed of throwing contribute to the efficiency of the tool . For the tall palms, a sickle attached to a ong pole is used and the job is more difficult compared to the short palms. Lifting of pole and cutting jobs require great effort and skills. This paper describes the basic design needs in developing an appropriate device that is practical for field use. A prototype design was developed and tested.

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