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Physico.chemical Properties of Inorganic Materials Currently Used as Root Medium Components for Crop Production in Korean Plant Factories (국내에서 식물공장용 배지 재료로 유통되는 무기물의 토양 물리화학적 특성)

  • Shin, Bo Kyoung;Son, Jung Eek;Choi, Jong Myung
    • Journal of Bio-Environment Control
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    • v.21 no.4
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    • pp.336-342
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    • 2012
  • Inorganic materials were commonly used as container media in domestic plant factories. Objective of this research was to secure the information in soil physical and chemical properties of inorganic materials such as vermiculites and perlites. To achieve this, 12 gold and silver vermiculites from China, Zimbabwe, and South Africa and 5 perlites from China were collected based on the marketing grades (MG) in particle sizes and analyzed for determination of their characteristics. The percentage of particles larger than $710{\mu}m$, in China perlite MG 3~5 mm, China silver vermiculites MG > 8 mm and MG 3~8 mm were 99.9%, 99.8%, and 99.7%, respectively, which were much higher than 28.4% in China gold vermiculite MG 0.3~1.0 mm, 14.0% in perlite MG < 1.0 mm, and 12.6% of Zimbabwe silver vermiculite MG < 1.0 mm. The container capacities of perlite MG < 1.0 mm and South Africa silver vermiculite MG 0.25~1.0 mm were 72.0% and 71.1%, respectively. The air space in China silver vermiculite MG 3~8 mm was 49.3% which was higher than other materials tested. However, the China gold and silver vermiculites MG 0.3~1 mm had 3.5% and 2.4% in air space indicating that possible problems could occur in soil aeration when they are used for container media. The percentage of easily available and buffering water of China gold vermiculite MG 0.3~1 mm and perlite MG < 1.0 mm were the highest among test materials. The ranges of pH and electrical conductivity were 6.36 to 10.7 and 0.032 to $0.393dS{\cdot}m^{-1}$ in vermiculites and 7.78 to 8.62 and 0.030 to $0.041dS{\cdot}m^{-1}$ in perlite, respectively. The cation exchange capacity of China silver vermiculite MG 0.3~1 mm were $14.7cmol{\cdot}kg^{-1}$ that was 10 times as high as $0.34cmol{\cdot}kg^{-1}$ in perlite MG 1~2.5 mm. The vermiculites had the higher contents of exchangeable cations such as Ca, K, and Na, than those of perlites.

A Study on the Position of the Maxillary Anterior Teeth in Korean Adults with Natural Dentition (한국 성인 유치악자의 상악전치 위치에 관한 연구)

  • Jeong, Chang-Mo;Park, Jeong-Hyeong
    • Journal of Dental Rehabilitation and Applied Science
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    • v.21 no.2
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    • pp.105-111
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    • 2005
  • It is essential to establish the suitable position for artificial maxillary anterior teeth, because of not only esthetics, phonetics, mastication, but also optimal position of artificial posterior teeth for the construction of functional and esthetic prostheses. Anatomic landmarks have been used in the arrangement of artificial teeth. Such as incisive papilla and palatal rugae are useful landmarks for positioning occlusal rim and upper anterior artificial teeth because they are relatively stable and to be identified on master cast. Therefore, if average distance between maxillary anterior teeth and landmarks in dentate subjects are measured and applied, appropriate position of occlusal rim can be initially established. In this study, to present a guide to the position of the occlusal rim for upper anterior teeth of edentulous patients, horizontal distance between anatomic landmarks were measured. Maxillary casts were made in 72 Korean dentate subjects. Horizontal distance between central incisor and incisive papilla, between incisive papilla and intercanine line, and between primary palatine rugae and gingival margin of canine were measured on each cast. The results of this study were as follows ; 1. The mean distance from the incisal edge of central incisor to the posterior border of incisive papilla was 12.1 mm (Male 12.2 mm, Female 11.9 mm). 2. The mean distance between posterior border of incisive papilla and intercanine line was 3.5 mm (Male 3.4 mm, Female 3.6 mm / Left 3.6 mm, Right 3.4 mm). 3. The mean distance from the palatal gingival margin of canine to the lateral border of primary palatine rugae was 2.4 mm (Male 2.4 mm, Female 2.4 mm / Left 2.4 mm, Right 2.3 mm). 4. On all measured items, there were no significant differencies in measured values between male and female, and between left and right sides. (P>0.05).

Distortion of the Dose Profile in a Three-dimensional Moving Phantom to Simulate Tumor Motion during Image-guided Radiosurgery (방사선수술에서 종양 움직임을 재현시킨 움직이는 팬텀을 이용하여 선량 분포의 왜곡에 대한 연구)

  • Kim, Mi-Sook;Ha, Seong-Hwan;Lee, Dong-Han;Ji, Young-Hoon;Yoo, Seong-Yul;Cho, Chul-Koo;Yang, Kwang-Mo;Yoo, Hyung-Jun;Seo, Young-Seok;Park, Chan-Il;Kim, Il-Han;Ye, Seong-Jun;Park, Jae-Hong;Kim, Kum-Bae
    • Radiation Oncology Journal
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    • v.25 no.4
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    • pp.268-277
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    • 2007
  • Purpose: Respiratory motion is a considerable inhibiting factor for precise treatment with stereotactic radiosurgery using the CyberKnife (CK). In this study, we developed a moving phantom to simulate three-dimensional breathing movement and investigated the distortion of dose profiles between the use of a moving phantom and a static phantom. Materials and Methods: The phantom consisted of four pieces of polyethylene; two sheets of Gafchromic film were inserted for dosimetry. Treatment was planned to deliver 30 Gy to virtual tumors of 20, 30, 40, and 50 mm diameters using 104 beams and a single center mode. A specially designed robot produced three-dimensional motion in the right-left, anterior-posterior, and craniocaudal directions of 5, 10 and 20 mm, respectively. Using the optical density of the films as a function of dose, the dose profiles of both static and moving phantoms were measured. Results: The prescribed isodose to cover the virtual tumors on the static phantom were 80% for 20 mm, 84% for 30 mm, 83% for 40 mm and 80% for 50 mm tumors. However, to compensate for the respiratory motion, the minimum isodose levels to cover the moving target were 70% for the $30{\sim}50$ mm diameter tumors and 60% for a 20 mm tumor. For the 20 mm tumor, the gaps between the isodose curves for the static and moving phantoms were 3.2, 3.3, 3.5 and 1.1 mm for the cranial, caudal, right, and left direction, respectively. In the case of the 30 mm tumor, the gaps were 3.9, 4.2, 2.8, 0 mm, respectively. In the case of the 40 mm tumor, the gaps were 4.0, 4.8, 1.1, and 0 mm, respectively. In the case of the 50 mm diameter tumor, the gaps were 3.9, 3.9, 0 and 0 mm, respectively. Conclusion: For a tumor of a 20 mm diameter, the 80% isodose curve can be planned to cover the tumor; a 60% isodose curve will have to be chosen due to the tumor motion. The gap between these 80% and 60% curves is 5 mm. In tumors with diameters of 30, 40 and 50 mm, the whole tumor will be covered if an isodose curve of about 70% is selected, equivalent of placing a respiratory margin of below 5 mm. It was confirmed that during CK treatment for a moving tumor, the range of distortion produced by motion was less than the range of motion itself.

Temperature Changes in Dentin upon Pulsed Nd:YAG Lasing Distance (Pulsed Nd:YAG 레이저 조사거리에 따른 상아질의 온도변화)

  • Jae-Hyung Kim;Woo-Cheon Kee
    • Journal of Oral Medicine and Pain
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    • v.20 no.2
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    • pp.327-334
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    • 1995
  • In order to observe the influence of pulsed Nd:YAG laser at its out-of-contact with dentin on tooth temperature, we have applied pulsed Nd:YAG laser to 2mm thick dentin sample at a point of contact and from a distance of 1mm, 2mm, 3mm and 4mm with an energy of 0.3W, 0.5W, 0.8W, 1.5W and 2.0W. They were exposed to periods of 3 seconds, 6 seconds, 9 seconds and 15 seconds respectively and measured temperature changes. The results as follows : 1. When the time ad intensity of power were constant, the temperature changes on dentin of tooth depended on the distance. The temperature increased when the laser intensity increased bu two other conditions were contact. 2. At the point of contact, the temperature has risen over $5^{\circ}C$ regrdless of intensity of the power or the time. However, there was $5^{\circ}C$ fluctuation with 0.3 W for 3 seconds treatment. 3. The temperature change was less than $5^{\circ}C$ thermal change at the distance of 1mm and 2mm respectively when lased for 3 seconds, 6 seconds, 12 seconds and 15 seconds with 0.3 W. Similar results were observed at 3 and 6 seconds treatment with 0.5 W and at 3 seconds treatment with 0.8 and 1.0W respectively. 4. It showed less than 5(C thermal change when lased for 3 seconds, 6 seconds, 9 seconds, 12 seconds and 15 seconds with 0.3W at the distance of 3mm and 4mm. The same results were seen in 3 seconds, 6 seconds and 9 seconds treatment with 0.5W and in 3 seconds with 0.8W and 1.0W respectively. As we have seen the above, the results has indicated that pulsed Nd:YAG lasing at its off contact on dentin of 2mm thickness will not cause irreversible changes if lasing intensity, lasing distance and lasing time are appropriate.

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Development of Immobilization Devices for Patients with Pelvic Malignancies and a Feasibility Evaluation during Radiotherapy (골반부 암 환자를 위한 고정기구 개발 및 방사선치료 시 효용성 평가)

  • Park, Jong-Min;Park, Yang-Kyun;Cho, Woong;Park, Charn-Il;Ha, Sung-Whan
    • Radiation Oncology Journal
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    • v.25 no.2
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    • pp.134-144
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    • 2007
  • [ $\underline{Purpose}$ ]: Immobilization devices that improve the setup reproducibility of pelvic cancer patients and that provide comfort to patients during radiotherapy were designed and the feasibility of the devices was evaluated. $\underline{Materials\;and\;Methods}$: A customized device was designed to immobilize a knee, thigh, and foot of a patient. Sixty-one patients with prostate cancer were selected and were divided into two groups-with or without devices. The setup errors were measured with respect to bony landmarks. The difference between digitally reconstructed radiographs (DRR) and simulation films, and the differences between DRR and portal films were measured. $\underline{Results}$: The left-right (LR), anterior-posterior (AP) and craniocaudal (CC) errors between the DRR and simulation films were $1.5{\pm}0.9\;mm$, $3.0{\pm}3.6\;mm$, and $1.6{\pm}0.9\;mm$, respectively without devices. The errors were reduced to $1.3{\pm}1.9\;mm$, $1.8{\pm}1.5\;mm$ and $1.1{\pm}1.1\;mm$, respectively with the devices. The errors between DRR and portal films were $1.6{\pm}1.2\;mm$, $4.0{\pm}4.1\;mm$, and $4.2{\pm}5.5\;mm$, respectively without the devices and were reduced to $1.0{\pm}1.8\;mm$, $1.2{\pm}0.9\;mm$, and $1.2{\pm}0.8\;mm$, respectively, with the devices. The standard deviations among the portal films were 1.1 mm, 2.1 mm, and 1.0 mm at each axis without the devices and 0.9 mm, 1.6 mm and 0.8 mm with the devices. The percentage of setup errors larger than 3 mm and 5 mm were significantly reduced by use of the immobilization devices. $\underline{Conclusion}$: The designed devices improved the setup reproducibility for all three directions and significantly reduced critical setup errors.

A study on the Nutritional status for School-Children of Bong-do Primary School, Busan, Korea, 1972. (부산 송도국민학교 아동들의 영양 상태에 관한 연구)

  • 오영숙
    • Journal of Korean Academy of Nursing
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    • v.3 no.3
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    • pp.73-77
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    • 1973
  • A study on the nutritional status for school-children has been carried out 1,700 school- children of Song-do primary school located in Song-do beach, Busan, Korea, from November to-December, 1972. The evaluation of the nutritional status has been carried out through skin-fold thickness and hemoglobin. The summarized results were as follows. : 1. Skinfolds thickness 1) Subcellular skinfolds thickness . Among boys, that was 3.5mm in the age 6 and 5.4mm in the age 11 Among girls, that was 4.2mm in the age 6 and 7.6mm in the age 11. Girls were thicker than toys in the all age. 2) Upper-arm skinfolds thickness Among boys, that was 5.0mm in the age 6 and 6.8mm in the age 11. Among girls, that was 6.2mm in the age 6 and 8.7mm in the age 11. Girls were thicker than toys in the all age. 3)Abdominal skinfolds thickness. Among boys, that was 4.0mm in the age 6, and 6.4mm in the age 11. Among girls that was 4.0mm in the age 0, and 8.4mm in the age 11. Girls were thicker than boys in the all age. 2. Hemoglobin Proportional range of hemoglobin were observed as 12.2-12.8 gm/㎗.

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Effects of Ligature of Mandibular Gland and Sublingual Gland on the Mandibular Gland in Dogs (개에서 턱밑샘관 및 혀밑샘관의 결찰이 턱밑샘에 미치는 영향)

  • 황학균;김명철
    • Journal of Veterinary Clinics
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    • v.16 no.1
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    • pp.57-64
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    • 1999
  • It was performed to evaulate the effects of occlusion of mandibular gland and sublingual gland on the mandibular gland in dogs. The occlusion of mandibular gland and sublingual gland was induced by ligature in clinically normal dogs, and ultrasonograpic appearance, hematological changes and histological changes of the mandibular gland were observed daily during 6 days. The results were as follows. 1. The length, width, circumference and area of the mandibular gland in clinically normal dogs were 25.1 mm, 8.4 mm, 56.4 mm and 163.0 $\textrm{mm}^2$ in the left, and 23.4 mm, 8.0 mm, 53.3 mm and 141.6 $\textrm{mm}^2$in the right. 2. The length, width, circumference and area of the mandibular gland were gradually increased after ligature of the salivary duct, and revealed maximum values, as 33.4 mm, 10.9 mm, 73.0 mm and 287.2 $\textrm{mm}^2$, respectively, at 24 hours after ligature, and returned to normal size at 3 days after ligature. 3. The size of the opposite mandibular gland without ligature was also gradually increased until 24 hours, and returned to normal size at 3 days, similar to the changes of the mandibular gland with ligature. 4. There were no significant changes after ligature of the salivary duct in hematological findings. 5. In histopathological findings, the major of glandular alveoli was enlarged at 24 hours after ligature of the salivary duct, and neutrophils and monocytes were infiltrated at 6 days after ligature.

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$^{192}$Ir 선원의$\gamma$선 자기흡수효과 측정

  • 조운갑;한현수;박춘득;박울재;이철영
    • Proceedings of the Korean Nuclear Society Conference
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    • 1998.05b
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    • pp.752-756
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    • 1998
  • 산업용 및 의료용으로 사용되는 $^{192}$ Ir 방사선원에 대한 $\psi$선 자기흡수효과인자를 실험을 통하여 구하였다. 이를 위하여 3 mm $\psi$ x 3 mm t, 2.5 mm $\psi$ x 2.5 mm t, 2 mm $\psi$ x 2 mm Ir의 원주형 Ir 표적과 3 mm $\psi$ x 0.25 mm t, 3 mm $\psi$ x 0.1 mm t의 원판형 Ir 표적을 하나로의 PTS(Pneumatic Transport System)조사공에서 중성자 조사하였다. 이온전리함을 사용하여 각 Ir 표적의 방사능을 측정하고 계산에 의해서 구한 생성방사능 값과의 비를 구하는 방법으로 $^{192}$ Ir의 ${\gamma}$선 자기흡수효과인자를 구하였다. 이 값들은 원주형 표적에 대하여 각각 0.614, 0.687, 0.704 였고 원판형 표적에 대하여 각각 0.827, 0.875 였다. 원주형 Ir 표적내부의 중성자 자기흡수효과의 정도를 알아보기 위하여 2.5 mm $\psi$ x 0.25 mm t Ir 표적 10장을 포개어 중성자 방사화시킨 후 각 표적의 방사능을 측정한 결과 가장 바깥쪽 표적의 방사능이 중심부에 위치한 표적보다 약 2배정도 방사화가 많이 일어남을 알 수 있었다. 이번에 구한 ${\gamma}$선 자기흡수효과인자는 향후 산업용 및 의료용으로 사용되는 $^{192}$ Ir 방사선원의 사용자에게 제공되는 최종방사능을 평가하는데 유용하게 사용될 수 있다.

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Development of a Multi-joint Robot Manipulator for Robot Milking System (로봇 착유시스템을 위한 다관절 매니퓰레이터 개발)

  • Kim W.;Lee D. W.
    • Journal of Biosystems Engineering
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    • v.30 no.5 s.112
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    • pp.293-298
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    • 2005
  • The purpose of this study was the development of a multi-joint robot manipulator for milking robot system. The multi-joint robot manipulator was controlled by 5 drivers with driver controller through the position information obtained from the image processing system. The robot manipulator to automatically attach each teat cup to the teats of a milking cow was developed and it's motion was accurately measured with error rate. Results were as follows. 1. Maximum errors in position accuracy were 4mm along X-axis, 4.5mm along Y-axis and 0.9mm along Z-axis. Absolute distance errors were maximum 4.8mm, minimum 2.7mm, and average 3.6mm. 2. Errors of repeatability were maximum 3.0mm along X-axis, 3.0mm along Y-axis, and 0.5mm along Z-axis. Distance error values were maximum 3.2mm, minimum 2.2mm, and average 2.5mm. It is envisaged that multi-joint robot manipulator can be applicate to milking robot system being developed in consideration of the experiment results.

한국산 해마의 서식지 보고 및 초기생활사

  • Roh, Seom;Choi, Yeong-Ung;Yoon, Yeong-Seok;Chung, Min-Min
    • Proceedings of the Korean Aquaculture Society Conference
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    • 2003.10a
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    • pp.56-57
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    • 2003
  • 실고기과(Syngnathidae)에 속하는 해마류는 5300만년전부터 지구상에 존재해온 어류로 전 세계적으로 72%에 해당하는 32종이 인도-태평양연안에서 서식하는 것으로 알려져 있다. 그리고 약제와 관상무역에서 넓은 시장을 형성하며 그 수요가 지속적으로 증가하고 있다. 그러나, 국내에서는 아직 해마의 서식지와 초기생활사에 대한 연구가 전무한 실정으로 이번 연구에서는 최근 발견된 한국산 해마의 서식지와 채집된 2종 해마의 치어 초기생활사를 보고한다. 2003년 8~9월에 전라남도 여수시와 고흥군 주변해역에서 해마, Hippocampus coronatus 18마리(전장 40.8~79.5mm), 산호해마 H, japonicus 80마리(전장 28.1~56.3mm)가 채집되었고, 순환여과식 사육수조에서 사육하면서 자연산란한 치어를 대상으로 초기생활사를 관찰하였다. 사육은 유리로 된 사각수조(50$\times$30$\times$28cm)에 여과조(26$\times$26$\times$28cm)를 연결한 순환여과시스템에서 실시하였으며, 사육수온은 26.0$\pm$0.5$^{\circ}C$, 염분 32$\textperthousand$ 전후, pH 7.74 전후 그리고 DO 6.8mg/$\ell$ 전후였다. 먹이는 부화 2일령까지는 로티퍼, Brachionus rotundiformis를 단독 급이하였고, 부화 후 3일령부터는 로티퍼와 알테미아, Artemia sp.를 혼합 급이하였다. 치어의 성장 측정은 만능투영기를 이용하여 각 20마리를 무작위 추출하여 측정하였고 각 측정 부위별로 0.001mm까지 측정하였다. 이번 조사에서 전라남도 여수시와 고흥군 주변해역에서 채집된 해마류는 해마(H. coronatus) 18개체, 산호해마(H. japonicus) 80개체의 2종이 채집되었고 순환여과시스템에 사육하던 중 5회 산란하였다. 해마(H. coronatus)는 부화 후 9~10일째에 Total length 11.67~15.98mm(평균 5.19mm, n=20), Trunk length 2.48~3.31mm(평균 2.63mm, n=20), Head length 1.31~2.27mm(평균 1.76mm, n=20) 그리고 Snout length 0.74~l.67mm(평균 1.09mm, n=20) 이었다. 한편, 부화 직후 산호해마(H. japonicus)의 치어는 난황을 거의 흡수한 상태였으며 부화 후 2~3일째 Total length 4.29~5.70mm(평균 5.09mm, n=30), Trunk length 2.06~2.73mm(평균 2.55mm, n=30), Head length 1.50~l.79mm(평균 1.06mm, n=30) 그리고 Snout length 0.81~l.14mm(평균 0.97mm, n=30)였다. 그리고 부화 후 5~6일째에는 Total length 4.33~6.33mm(평균 5.19mm, n=20), Trunk length로 2.48~3.31mm(평균 2.63mm, n=20), Head length 1.31~2.27mm(평균 1.76mm, n=20) 그리고 Snout length 0.74~l.67mm(평균 1.09mm, n=20) 이었다.

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