• Title/Summary/Keyword: 반응기구

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Selectivity of Bleaching Herbicides Caused by Physiological Differences between Rice and Barnyardgrass (벼와 피의 생리적(生理的) 차이(差異)에 의한 백화형(白化型) 제초제(除草劑)의 선택성(選擇性))

  • Na, J.Y.;Kim, J.S.;Kim, T.J.;Cho, K.Y.;Pyon, J.Y.
    • Korean Journal of Weed Science
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    • v.12 no.2
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    • pp.89-101
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    • 1992
  • In this study, various physiological and biochemical experiments were conducted to know whether the selectivity between rice and barnyardgrass treated with bleaching herbicides containing diphenyl ether compounds was also partly based on their basic physiological proterties such as peroxidation ability, membrane stability or antioxidant system. It seemed to be partly based on the differences of their physiological characteristics that barnyardgrass was commonly more susceptible to most of the bleaching herbicides than rice. The scenescence of intact leaf segment was more rapid in barnyardgrass than in rice, indicating that barnyardgrass is weak at early stage. Also pigment metabolic ability, antioxidant enzyme activities(peroxidase, catalase, superoxide dismutase, glutathione reductase) and antioxidant content (tocopherol, ascorbic acid, glutathione, carotenoids) were lower in barnyardgrass on the basic of fresh weight. However, lipoxygenase activity and the content of unsaturated fatty acid which is vulnerable to oxygen radicals were higher in barnyardgrass, suggesting that barnyardgrass seedling bave a properties easy to be peroxidized. The differences of PPIX (protoporphyrin IX) or carotenoid content, which are the primary substances inducing herbicide activity, were not related to the selectivity between rice and barnyardgrass.

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Characteristics of Beach Change and Sediment Transport by Field Survey in Sinji-Myeongsasimni Beach (신지명사십리 해수욕장에서 현장조사에 의한 해빈변화와 퇴적물이동 특성)

  • Jeong, Seung Myong;Park, Il Heum
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.5
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    • pp.594-604
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    • 2021
  • To evaluate the causes of beach erosion in Sinji-Myeongsasimni Beach, external forces, such as tides, tidal currents, and waves, were observed seasonally from March 2019 to March 2020, and the surface sediments were analyzed for this period. In addition, the shoreline positions and beach elevations were regularly surveyed with a VRS GPS and fixed-wing drone. From these field data, the speed of the tidal currents was noted to be insufficient, but the waves were observed to af ect the deformation of the beach. As the beach is open to the southern direction, waves of heights over 1 m were received in the S-SE direction during the spring, summer, and fall seasons. Large waves with heights over 2 m were observed during typhoons in summer and fall. Because of the absence of typhoons for the previous two years from July 2018, the beach area over datum level (DL) as of July 2018 was greater by 30,138m2 compared with that of March 2019, and the beach area as of March 2020 decreased by 61,210m2 compared with that of March 2019 because of four typhoon attacks after July 2018. The beach volume as of March 2019 decreased by 5.4% compared with that of July 2018 owing to two typhoons, and the beach volume as of September 2019 decreased by 7.3% because of two typhoons during the observation year. However, the volume recovered slightly by about 3% during fall and winter, when there were no high waves. According to the sediment transport vectors by GSTA, the sediments were weakly influxed from small streams located at the center of the beach; the movement vectors were not noticeable at the west beach site, but the westward sediment transport under the water and seaward vectors from the foreshore beach were prominently observed at the east beach site. These patterns of westward sediment vectors could be explained by the angle between the annual mean incident wave direction and beach opening direction. This angle was inclined 24° counterclockwise with the west-east direction. Therefore, the westward wave-induced currents developed strongly during the large-wave seasons. Hence, the sand content is high in the west-side beach but the east-side beach has been eroded seriously, where the pebbles are exposed and sand dune has decreased because of the lack of sand sources except for the soiled dunes. Therefore, it is proposed that efforts for creating new sediment sources, such as beach nourishment and reducing wave heights via submerged breakwaters, be undertaken for the eastside of the beach.

Effects of Low Air Temperature and Light Intensity on Yield and Quality of Tomato at the Early Growth Stage (정식 초기의 저온·저일조가 토마토 수량·품질에 미치는 영향)

  • Wi, Seung Hwan;Yeo, Kyung-Hwan;Choi, Hak Soon;Yu, Inho;Lee, Jin Hyong;Lee, Hee Ju
    • Journal of Bio-Environment Control
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    • v.30 no.4
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    • pp.448-454
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    • 2021
  • This study was conducted to the effect of low air temperature and light intensity conditions on yield and quality of tomato at the early stage of growth in Korea. Inplastic greenhouses, low temperature and low temperature with shade treatments were performed from 17 to 42 days after plant. Tomato growing degree days were decreased 5.5% due to cold treatment during the treatment period. Light intensity decreased 74.7% of growing degree days due to shade. After commencing treatments, the plant growth decreased by low temperature and low radiation except for height. Analysis of the yield showed that the first harvest date was the same, but the yield of the control was 3.3 times higher than low temperature with shade treatment. The cumulative yields at 87 days after transplanting were 1734, 1131, and 854 g per plant for control, low temperature, and low temperature with shade, respectively. The sugar and acidity of tomatoes did not differ between treatment and harvesting season. To investigate the photosynthetic characteristics according to the treatment, the carbon dioxide reaction curve was analyzed using the biochemical model of the photosynthetic rate. The results showed that the maximum photosynthetic rate, J (electric transportation rate), TPU (triose phosphate utilization), and Rd (dark respiration rate) did not show any difference with temperature, but were reduced by shading. Vcmax (maximum carboxylation rate) was decreased depending on the low temperature and the shade. Results indicated that low temperature and light intensity at the early growth stage can be inhibited the growth in the early stage but this phenomenon might be recovered afterward. The yield was reduced by low temperature and low intensity and there was no difference in quality.

Change Detection for High-resolution Satellite Images Using Transfer Learning and Deep Learning Network (전이학습과 딥러닝 네트워크를 활용한 고해상도 위성영상의 변화탐지)

  • Song, Ah Ram;Choi, Jae Wan;Kim, Yong Il
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.3
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    • pp.199-208
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    • 2019
  • As the number of available satellites increases and technology advances, image information outputs are becoming increasingly diverse and a large amount of data is accumulating. In this study, we propose a change detection method for high-resolution satellite images that uses transfer learning and a deep learning network to overcome the limit caused by insufficient training data via the use of pre-trained information. The deep learning network used in this study comprises convolutional layers to extract the spatial and spectral information and convolutional long-short term memory layers to analyze the time series information. To use the learned information, the two initial convolutional layers of the change detection network are designed to use learned values from 40,000 patches of the ISPRS (International Society for Photogrammertry and Remote Sensing) dataset as initial values. In addition, 2D (2-Dimensional) and 3D (3-dimensional) kernels were used to find the optimized structure for the high-resolution satellite images. The experimental results for the KOMPSAT-3A (KOrean Multi-Purpose SATllite-3A) satellite images show that this change detection method can effectively extract changed/unchanged pixels but is less sensitive to changes due to shadow and relief displacements. In addition, the change detection accuracy of two sites was improved by using 3D kernels. This is because a 3D kernel can consider not only the spatial information but also the spectral information. This study indicates that we can effectively detect changes in high-resolution satellite images using the constructed image information and deep learning network. In future work, a pre-trained change detection network will be applied to newly obtained images to extend the scope of the application.

Genetic Environments of Au-Ag-bearing Geumhwa Hydrothermal Vein Deposit (함 금-은 금화 열수 맥상광상의 생성환경)

  • Lee, Sunjin;Choi, Sang-Hoon
    • Economic and Environmental Geology
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    • v.54 no.1
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    • pp.49-60
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    • 2021
  • The Geumhwa Au-Ag deposit is located within the Cretaceous Gyeongsang basin. Mineral paragenesis can be divided into two stages (stage I and II) by major tectonic fracturing. Stage II is economically barren. Stage I, at which the precipitation of major ore minerals occurred, is further divided into three substages(early, middle and late) with paragenetic time based on minor fractures and discernible mineral assemblages: early substage, marked by deposition of pyrite with minor wolframite; middle substage, characterized by introduction of electrum and base-metal sulfides with Cu-As and/or Cu-Sb sulfosalts; late substage, marked by hematite and Bi-sulfosalts with secondary minerals. Changes in vein mineralogy reflect decreases in temperature and sulfur fugacity with a concomitant increase in oxygen fugacity. Fluid inclusion data indicate progressive decreases in temperature and salinity within each substage with increasing paragenetic time. During the early portion of stage I, high-temperature (≥410℃), high-salinity fluids (up to ≈44 equiv. wt. % NaCl) formed by condensation during decompression of a magmatic vapor phase. During waning of early substage, high-temperature, high-salinity fluids gave way to progressively cooler, more dilute fluids associated with main Au-Ag mineralization (middle) and finally to ≈180℃ and ≥0.7 equiv. wt. % NaCl fluids associated with hematite and sulfosalts (± secondary) mineralization (late substage). These trends are interpreted to indicate progressive mixing of high- and medium to low-salinity hydrothermal fluids with cooler, more dilute, oxidizing meteoric waters. The Geumhwa Au-Ag deposit may represent a vein-type system transitional between porphyry-type and epithermal-type.

Lipopolysaccharide-induced Synthesis of IL-1beta, IL-6, TNF-alpha and TGF-beta by Peripheral Blood Mononuclear Cells (내독소에 의한 말초혈액 단핵구의 IL-1beta, IL-6, TNF-alpha와 TGF-beta 생성에 관한 연구)

  • Jung, Sung-Hwan;Park, Choon-Sik;Kim, Mi-Ho;Kim, Eun-Young;Chang, Hun-Soo;Ki, Shin-Young;Uh, Soo-Taek;Moon, Seung-Hyuk;Kim, Yang-Hoon;Lee, Hi-Bal
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.4
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    • pp.846-860
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    • 1998
  • Background: Endotoxin (LPS : lipopolysaccharide), a potent activator of immune system, can induce acute and chronic inflammation through the production of cytokines by a variety of cells, such as monocytes, endothelial cells, lymphocytes, eosinophils, neutrophils and fibroblasts. LPS stimulate the mononucelar cells by two different pathway, the CD14 dependent and independent way, of which the former has been well documented, but not the latter. LPS binds to the LPS-binding protein (LBP), in serum, to make the LPS-LBP complex which interacts with CD14 molecules on the mononuclear cell surface in peripheral blood or is transported to the tissues. In case of high concentration of LPS, LPS can stimulate directly the macrophages without LBP. We investigated to detect the generation of proinflammatory cytokines such as interleukin 1 (IL-1), IL-6 and TNF-$\alpha$ and fibrogenic cytokine, TGF-$\beta$, by peripheral blood mononuclear cells (PBMC) after LPS stimulation under serum-free conditions, which lacks LBPs. Methods : PBMC were obtained by centrifugation on Ficoll Hypaque solution of peripheral venous bloods from healthy normal subjects, then stimulated in the presence of LPS (0.1 ${\mu}g/mL$ to 100 ${\mu}g/mL$ ). The activities of IL-1, IL-6, TNF, and TGF-$\beta$ were measured by bioassaies using cytokines - dependent proliferating or inhibiting cell lines. The cellular sources producing the cytokines was investigated by immunohistochemical stains and in situ hybridization. Results : PBMC started to produce IL-6, TNF-$\alpha$ and TGF-$\beta$ in 1 hr, 4 hrs and 8hrs, respectively, after LPS stimulation. The production of IL-6, TNF-$\alpha$ and TGF-$\beta$ continuously increased 96 hrs after stimulation of LPS. The amount of production was 19.8 ng/ml of IL-6 by $10^5$ PBMC, 4.1 ng/mL of TNF by $10^6$ PBMC and 34.4 pg/mL of TGF-$\beta$ by $2{\times}10^6$ PBMC. The immunoreactivity to IL-6, TNF-$\alpha$ and TGF-$\beta$ were detected on monocytes in LPS-stimulated PBMC. Some of lymphocytes showed positive immunoreactivity to TGF-$\beta$. Double immunohistochemical stain showed that IL-1$\beta$, IL-6, TNF-$\alpha$ expression was not associated with CD14 postivity on monocytes. IL-1$\beta$, IL-6, TNF-$\alpha$ and TGF-$\beta$mRNA expression were same as observed in immunoreactivity for each cytokines. Conclusion: When monocytes are stimulated with LPS under serum-free conditions, IL-6 and TNF-$\alpha$ are secreted in early stage of inflammation. In contrast, the secretion of TGF-$\beta$ arise in the late stages and that is maintained after 96 hrs. The main cells releasing IL-1$\beta$, IL-6, TNF-$\alpha$ and TGF-$\beta$ are monocytes, but also lymphocytes can secret TGF-$\beta$.

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Studies on the Functional Interrelation between the Vestibular Canals and the Extraocular Muscles (미로반규관(迷路半規管)과 외안근(外眼筋)의 기능적(機能的) 관계(關係)에 관(關)한 연구(硏究))

  • Kim, Jeh-Hyub
    • The Korean Journal of Physiology
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    • v.8 no.2
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    • pp.1-17
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    • 1974
  • This experiment was designed to explore the specific functional interrelations between the vestibular semicircular canals and the extraocular muscles which may disclose the neural organization, connecting the vestibular canals and each ocular motor nuclei in the brain system, for vestibuloocular reflex mechanism. In urethane anesthetized rabbits, a fine wire insulated except the cut cross section of its tip was inserted into the canals closely to the ampullary receptor organs through the minute holes provided on the osseous canal wall for monopolar stimulation of each canal nerve. All extraocular muscles of both eyes were ligated and cut at their insertio, and the isometric tension and EMG responses of the extraocular muscles to the vestibular canal nerve stimulation were recorded by means of a physiographic recorder. Upon stimulation of the semicircular canal nerve, direction if the eye movement was also observed. The experimental results were as follows. 1) Single canal nerve stimulation with high frequency square waves (240 cps, 0. 1 msec) caused excitation of three extraocular muscles and inhibition of remaining three muscles in the bilateral eyes; stimulation of any canal nerve of a unilateral labyrinth caused excitation (contraction) of the superior rectus, superior oblique and medial rectus muscles and inhibition (relaxation) of the inferior rectus, inferior oblique and lateral rectos muscles in the ipsilateral eye, and it caused the opposite events in the contralateral eye. 2) By the overlapped stimulation of triple canal nerves of a unilateral labyrinth, unidirectional (excitatory or inhibitory) summation of the individual canal effects on a given extraocular muscles was demonstrated, and this indicates that three different canals of a unilateral vestibular system exert similar effect on a given extraocular muscles. 3) Based on the above experimental evidences, a simple rule by which one can define the vestibular excitatory and inhibitory input sources to all the extraocular muscles is proposed; the superior rectus, superior oblique and medial rectus muscles receive excitatory impulses from the ipsilateral vestibular canals, and the inferior rectus, inferior oblique and lateral rectus muscles from the contralateral canals; the opposite relationship applies for vestibular inhibitory impulses to the extraocular muscles. 4) According to the specific direction of the eye movements induced by the individual canal nerve stimulation, an extraocutar muscle exerting major role (a muscle of primary contraction) and two muscles of synergistic contraction could be differentiated in both eyes. 5) When these experimental results were compared to the well known observations of Cohen et al. (1964) made in the cats, extraocular muscles of primary contraction were the same but those of synergistic contraction were partially different. Moreover, the oblique muscle responses to each canal nerve excitation appeared to be all identical. However, the responnes of horizontal (medial and lateral) and vertical (superior and inferior) rectus muscles showed considerable differences. By critical analysis of these data, the author was able to locate theoretical contradictions in the observations of Cohen et al. but not in the author's results. 6) An attempt was also made to compare the functional observation of this experiment to the morphological findings of Carpenter and his associates obtained by degeneration experiments in the monkeys, and it was able to find some significant coincidence between there two works of different approach. In summary, the author has demonstrated that the well known observations of Cohen et al. on the vestibulo-ocular interrelation contain important experimental errors which can he proved by theoretical evaluation and substantiated by a series of experiments. Based on such experimental evidences, a new rule is proposed to define the interrelation between the vestibular canals and the extraocular muscles.

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An Epidemiological Study on the Industrial Injuries among Metal Products Manufacturing Workers in Young-Dung-Po, Seoul (일부 금속 및 기계제품 제조업체 근로자들의 산업재해($1980{\sim}1981$)에 관한 조사)

  • Lee, Jung-Hee
    • Journal of Preventive Medicine and Public Health
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    • v.15 no.1
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    • pp.187-196
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    • 1982
  • The followings are the results of the study on industrial accidents occurred at 12 factories manufacturing metal products during the period of 2 years from January 1980 to December 1981 in the area of Yong-Dung-Po in Seoul. The results of the study are as follows: 1. The incidence rate of industrial injuries was 45.7 per 1,000 workers of the sample group and the rate of male (54.0) was three times higher than that of female (17.5). 2. In age groups, the highest rate was observed in the group of under 19 years old with 83.5, while the lowest in the group of 40s. 3. It was found that those who had short term of work experience produced a higher rate of injuries, particularly, the group of workers with less than 1 year of experience showed the highest rate of it as 48.1%. 4. In working time, the highest incidence rate occurred 3 and 7 hours after the beginning of their working showing the rate of 6.0 and 6.1 per 1,000 workers, respectively. 5. The highest incidence rate was observed on Monday as 8.4 per 1,000 workers, and it was 18.3% in aspect of the days of a week. 6. In aspect of the months of a year, the highest incidence was observed on July 1,000 workers and the next was on March as 4.8. These figures account for 11.8% of total occurrence in respective month. as 5. 4 per and 10.5% 7. In causes of injuries, the accident caused by power driven machinery showed the highest rate with 37.5%, the second was due to handling without machinery with 17.2%, and the third was due to falling objects with 14.2%, and striking against objects with 10.2%, and so on. 8. By parts of the body affected, the most injuries 84.3% of them occurred on both upper and lower extremities with the rate of 58.8% for the former and 25.5% for the latter. Fingers were most frequently injured with a rate of 40.3%. Comparing the sites of extremities affected, rate of injuries on the right side was 55.0% and 45.0% on the left side. 9. In the nature of injury, laceration and open wound were the highest with 34. 0%, the next was fracture and dislocation with 31. 9%, and sprain was the third with 8.1%. 10. On the duration of treatment, it lasted less than one month in 68.9% of the injured cases, of which 14.5% of the cases were recovered within 2 weeks, and 54.4% of them were treated more than 2 weeks. And the duration of the treatment tended to be prolonged in larger industries. 11. The ratio of insured accidents to uninsured accidents was 1 to 4.7.

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Evaluation of the Perception and Satisfaction of Working and Internship Abroad -By Undergraduates Studying in Culinary and Foodservice Departments- (해외 취업 및 인턴쉽에 대한 인식과 만족도에 관한 연구 -조리 및 외식관련 전공자를 대상으로-)

  • Choi, Young-Hee;Kim, Il-Soon;Kim, Soo-Yeun
    • Journal of the East Asian Society of Dietary Life
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    • v.19 no.2
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    • pp.287-294
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    • 2009
  • This study was conducted to evaluate the perception and satisfaction of undergraduates majoring in culinary arts and food service with working and internship abroad. The responses of the participants to 10 questions regarding perception and 13 questions regarding the importance and satisfaction with working and internship abroad were measured on a 5 point Likert scale. The primary results were as follows : 1) The subjects were composed of 50.9% male and 49.1% female students, of which 42.1% were employed and 57.9% experienced an internship abroad. 2) Most students went abroad to gain experience with respect to various foreign cultures in response to recommendations by the western cuisine department. 3) The items "I wish to conduct my affairs continuously"(M=4.21) and "I have good relationships with my colleagues at work"(M=4.11) received the highest points from male and female respondents, respectively. 4) Male students considered "cooperation among divisions"(M=4.11), "language skills"(M=4.38), and "kitchen environment"(M=4.34) to be very important. However, female students believed that "language skills"(M=4.36),"social relationships"(M=4.21), and "wage income"(M=4.18) were most important. Furthermore, male students were most satisfied with "company size" (M=4.28), "kitchen environment"(M=4.21), and "business hours"(M=4.10), while female students were most satisfied with "kitchen environment","incentive"(M=4.14) and "social relationships"(M=4.11).

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Clinical Experience of Three Dimensional Conformal Radiation Therapy for Non-Small Cell Lung Cancer (비소세포성 폐암에서 3차원 입체조형 방사선 치료 성적)

  • Choi Eun Kyung;Lee Byong Yong;Kang One Chul;Nho Young Ju;Chung Weon Kuu;Ahn Seung Do;Kim Jong Hoon;Chang Hyesook
    • Radiation Oncology Journal
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    • v.16 no.3
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    • pp.265-274
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    • 1998
  • Purpose : This prospective study has been conducted to assess the value of three dimensional conformal radiation therapy (3DCRT) for lung cancer and to determine its potential advantage over current treatment approaches. Specific aims of this study were to 1) find the most ideal 3DCRT technique 2) establish the maximum tolerance dose that can be delivered with 3DCRT and 3) identify patients at risk for development of radiation pneumonitis. Materials and Methods : Beginning in Nov. 1994, 95 patients with inoperable non-small cell lung cancer (stage I; 4, stage II; 1, stage IIIa; 14, stage IIIb; 76) were entered onto this 3D conformal trial Areas of known disease and elective nodal areas were initially treated to 45 Gy and then using 3DCRT technique 65 to 70 Gy of total dose were delivered to the gross disease. Sixty nine patients received 65 Gy of total dose and 26 received 70 Gy Seventy eight patients (82.1$\%$) also received concurrent MVP chemotherapy. 3DCRT plans were compared with 2D plans to assess the adequacy of dose delivery to target volume, dose volume histograms for normal tissue, and normal tissue complication Probabilities (NTCP). Results : Most of plans (78/95) were composed of non-coplanar multiple (4-8) fields. Coplanar segmented conformal therapy was used in 17 pateints, choosing the proper gantry angle which minimize normal lung exposure in each segment. 3DCRT gave the full dose to nearly 100$\%$ of the gross disease target volume in all patients. The mean NTCP for ipsilateral lung with 3DCRT (range; 0.17-0.43) was 68$\%$ of the mean NTCP with 2D treatment planning (range; 0.27-0.66). DVH analysis for heart showed that irradiated volume of heart could be significantly reduced by non-coplanar 3D approach especially in the case of left lower lobe lesion. Of 95 patients evaluable for response, 75 (79$\%$), showed major response including 25 (26$\%$) with complete responses and 50 (53$\%$) with partial responses. One and two rear overall survivals of stage III patients were 62.6$\%$ and 35.2$\%$ respectively. Twenty percent (19/95) of patients had pneumonitis; Eight patients had grade 1 pneumonitis and 11 other patients had grade 2. Comparison of the average of NTCP for lung showed a significant difference between patients with and without radiation pneumonitis. Average NTCP for Patients without complication was 62$\%$ of those with complications. Conclusions : This study showed that non-coplanar multiple fields (4-8) may be one of the ideal plans for 3DCRT for lung cancer. It also suggested that 3DCRT may provide superior delivery of high dose radiation with reduced risk to normal tissue and that NTCP can be used as a guideline for the dose escalation.

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