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Mineralogical Characterization of Asbestos in Soil at Daero-ri, Seosan, Chungnam, Korea (충남 서산 대로리 일대 토양 내 석면의 광물학적 특성)

  • Kim, Jaepil;Jung, Haemin;Song, Suckwhan;Lim, HoJu;Lee, WooSeok;Roh, Yul
    • Economic and Environmental Geology
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    • v.47 no.5
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    • pp.479-488
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    • 2014
  • Naturally occurring asbestos (NOA) from disturbance of rocks and soils has been overlooked as a source of exposure that could potentially have a detrimental impact on human health. But, few researches on mineralogical characteristics of NOA occurred in soils have been reported in Korea. Therefore, the objective of this study was to investigate the mineralogical characteristics of NOA occurred in soils at Daero-ri area, Seosan, Chungnam Province, Korea. Sedimentation method was used for particle size separation of the asbestos-containing soils. XRD and PLM analyses were used to characterize mineralogical characteristics and mineral assemblages in soils. SEM-EDS and TEM-EDS analyses were used to characterize mineral morphology and chemical composition. Particle size analyses of the asbestos-containing soils showed they were composed of 26-93% sand, 4-23% silt and 3-70% clay. Soil texture of the soils was mainly sand, sandy loam, sandy clay, and clay. PLM analyses of the soil showed that most of the soil contained asbestiform tremolite and actinolite. The average content of asbestos in the soil was 1.5 wt. %. Therefore, the soil can be classified into asbestos-contaminated soils based on U. S. Environmental Protection Agency classification (content of asbestos in contaminated soil > 1%). Morphologically different types of tremolite such as long fibrous, needle-like, fiber bundle, bladed and prismatic forms co-existed. Prismatic tremolite was dominant in sand fraction and asbestiform tremolite was dominant in silt fraction. This study indicates that the prismatic form of tremolite transform gradually into a fibrous form of tremolite due to soil weathering because tremolite asbestos was mainly existed in silt fraction rather than sand fraction.

Dendrochronological Analysis of Abies koreana W. at Mt. Halla, Korea: Effects of Climate Change on the Growths (한라산 구상나무(Abies koreana W.)의 연륜연대학적 연구 - 기후변화에 따른 생장변동 분석 -)

  • Koo, Kyung-Ah;Park, Won-Kyu;Kong, Woo-Seok
    • The Korean Journal of Ecology
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    • v.24 no.5
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    • pp.281-288
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    • 2001
  • The relationships between the growths of Abies koreana W. and climatic factors were analyzed by the use of tree-ring analysis at the subalpine belt of Mt. Halla National Park. The four cores were extracted from each 21 trees at north-facing slope (1,900m a.s.1.). The site chronology was established on the periods from 1912 to 1999. The growth of A. koreana was very poor, in particular in the years of 1982, 1988 and 1996. Simple correlation was employed to analyze the relationship between the growth of A. koreana and climatic factors. The result of simple correlation indicates that the growth of A. koreana represent positive correlations both with the mean temperatures of April and previous November, and the precipitation of previous December and January. The presence of large number of frost-damaged scars in the individual trees of A. koreana implies that local freezing temperature conditions at Mt. Halla have occurred in 1964, 1965 and 1966. The correlations between the fir chronology SOI(Southern Oscillation Index) of previous January, February and November were significantly positive. The growth ratio of A. koreana demonstrates that this species is sensitive to seasonal variations. As the winter temperature rises, the growth ratio of A. koreana decreases, on the other hand, the increase of autumn temperature accelerates the growth ratio of A. koreana. The growth decline of A. koreana was observed from 51 cores out of the 54 cores, and the overall growth declines have initiated at 1978, 1982 and 1988. Distinct growth decline of A. koreana in the range of 70% is noticed at 34 cores out of the 51 cores. The decline of, A. koreana growth appears to be related to the winter temperature which has increased since mid-1970s.

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Estimation on Optimum Fishing Effort of Walleye Pollock Fishery in the East Coast of Korea : Based on the Economic Analysis between Danish Seine Fishery and Trawl Fishery for Walleye Pollock (한국 동해 명태 어업의 적정어획노력량 추정 -동해구기선저인망어업과 동해구트롤어업의 경제성분석을 근거로-)

  • 이장욱
    • The Journal of Fisheries Business Administration
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    • v.22 no.2
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    • pp.75-99
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    • 1991
  • A quantitative analysis was carried out to monitor the commercial yield level of walleye pollock Theragra chalcogramma in the east coast of Korea, based on available data on catch and fishing effort, catch per unit of effort including fish prices from 1911 to 1988, using a traditional yield model. The results from the quantitative assessment were based to estimate maximum economic yield (MEY) and optimal fishing effort (E-opt) at MEY. On the other hand, interaction aspects between danish seine fishery and trawl fishery mainly targeting walleye pollock in the east coast of Korea were studied to predict optimal situation in fishing effort level from economic point of view which gives the most benefits to the two fisheries. Total production of walleye pollock in 1911 when its catch record was begun for the first time was about 12, 000 metric tons(M/T), and then the catch trend maintained nearly at the level of 50, 000 M/T per annum, showing a decreasing trend until 1930. The highest production from historical data base on walleye pollock fishery statistics was from the years in 1939 and 1940, about 270, 000 M/T and 26, 000 M/T, respectively. No production of the fish species was recorded during the years from 1943 to 1947, and from 1949 to 1951. From 1952 onwards annual production was only available from the southern part of 38$^{\circ}$N in the east coast. During two decades from 1952 to 1970, the production had sustained about less than 30, 000 M/T every year. Annual production showed an increasing trend from 1971, reaching a maximum level of approximately 162, 000 M/T in 1981. Afterwards, it has deceased sharply year after year and amounted to 180, 000 M/T in 1988. The catch composition of walleye pollock for different fishery segments during 1970~1988 showed that more than 70% of the total catch was from danish seine fishery until 1977 but from 1978 onwards, the catch proportion did not differ from one another, accounting for the nearly same proportion. Catch per unit of effort (CPUE) for both danish seine fishery and trawl fishery maintained a decline tendency after 1977 when the values of CPUE were at level of 800 kg/haul for the former fishery and 1, 300 kg/haul for the latter fishery, respectively. CPUEs of gillnet fishery during 1980~1983 increased to about 3.5 times as high value as in the years, 1970~1979 and during 1987~1988 it decreased again to the level of the years, 1970~1978. The bottom longline fishery's CPUE wa at a very low level (20 kg/basket) through the whole study years, with exception of the value (60 kg/basket) in 1980. Fishing grounds of walleye pollock in the east coast of Korea showed a very limited distribution range. Danish seine fishery concentrated fishing around the coastal areas of Sokcho and Jumunjin during January~February and October~December. Distributions of fishing grounds of trawl fishery were the areas along the coastal regions in the central part of the east coast. Gillnet and bottom longline fisheries fished walleye pollock mainly in the areas of around Sokcho and Jumunjin during January~February and December. Relationship between CPUEs' values from danish seine fishery and trawl fishery was used to standardize fishing effort to apply to surplus production model for estimating maximum sustainable yield (MSY) and optimum fish effort (F-opt) at MSY. The results suggested a MSY of 114, 000 M/T with an estimated F-opt of 173, 000 hauls per year. Based on the estimates of MSY and F-opt, MEY was estimated to be about 94, 000 M/T with a range of 81, 000 to 103, 000 M/T and E-opt 100, 000 hauls per year with a range of 80, 000 to 120, 000 hauls. The estimated values of MEY and E-opt corresponded to 82% of MSY and 58% of F-opt, respectively. An optimal situation in the fishing effort level, which can envisage either simultaneously maximum yield or maximum benefit for both danish seine fishery and trawl fishery, was determined from relationship between revenue and cost of running the fleet : the optimal fishing effort of danish seine fishery was about 52, 000 hauls per year, corresponding to 50 danish seiners and 27, 000 hauls per year which is equal nearly to 36 trawlers, respectively. It was anticipated that the net income from sustainable yield estimated from the respective optimal fishing effort of the two fisheries will be about 3, 800 million won for danish seine fishery and 1, 000 million won for trawl fishery.

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An Exploratory Study of Purchasing Decision Making and Adoption on the RFID Purchasing Customer (RFID 구매고객의 구매 의사결정과 수용에 대한 탐색적 연구)

  • Seo, Pil-Su;Jang, Jang-Yi;Shim, Kyeng-Su
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.3 no.4
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    • pp.89-116
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    • 2008
  • RFID (Radio Frequency Identification) is regarded as a core technology of ubiquitous computing. Although it has some technical limitations such as technological standardization of RFID tags as well as economical limitations, many companies around the world have already accepted RFID to improve their management efficiency. In this regard, this study is to meet with results that the adoption of RFID technology willbring opportunities that companies' operational process are improved and customer satisfaction is highly strengthened. This research focuses on providing more understanding for building RFID marketing strategy to suppliers who want to sell their RFID products to customers through analyzing purchasing process. The findings are as follows; First, the study shows that buying center members usually take product reliability and precision of technical specification in the case of new-task buying situation while they put their first purchasing priority on prices in the straight rebuy. Second, the finding presents that in new-task buying situation and the straight rebuy purchasing personnel get information about new products through product performance test, organizational engineers, opinions from other companies' purchasing personnel, and checking out samples. Third, this research demonstrates when it comes to purchasing risk in their first purchasing, the persons who are in charge of material purchasing are inclined to be aware of the risk most in technical problems, followed by financial problems and time delay problems in order. And in addition to those risks are mentioned above, once-again-purchasers take the risk like an opportunity loss for better products into consideration. Fourth, the study shows that the role of concerning departments makes no difference in each purchasing stage. Accordingly marketers need to beef up the differentiated strategy to persuade their customers Fifth, the findings of this study demonstrate that purchasing decision making is much influenced by the final users. So suppliers are supposed to perform the most active marketing strategy at the first stage of purchasing through various resources. Finally, the study presents that the suppliers who will have had close relationships with their customers need to give consistent information to them so that their customers can have lower motive in purchasing products from competitors.

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An Improved Online Algorithm to Minimize Total Error of the Imprecise Tasks with 0/1 Constraint (0/1 제약조건을 갖는 부정확한 태스크들의 총오류를 최소화시키기 위한 개선된 온라인 알고리즘)

  • Song, Gi-Hyeon
    • Journal of KIISE:Computer Systems and Theory
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    • v.34 no.10
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    • pp.493-501
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    • 2007
  • The imprecise real-time system provides flexibility in scheduling time-critical tasks. Most scheduling problems of satisfying both 0/1 constraint and timing constraints, while the total error is minimized, are NP-complete when the optional tasks have arbitrary processing times. Liu suggested a reasonable strategy of scheduling tasks with the 0/1 constraint on uniprocessors for minimizing the total error. Song et at suggested a reasonable strategy of scheduling tasks with the 0/1 constraint on multiprocessors for minimizing the total error. But, these algorithms are all off-line algorithms. In the online scheduling, the NORA algorithm can find a schedule with the minimum total error for the imprecise online task system. In NORA algorithm, EDF strategy is adopted in the optional scheduling. On the other hand, for the task system with 0/1 constraint, EDF_Scheduling may not be optimal in the sense that the total error is minimized. Furthermore, when the optional tasks are scheduled in the ascending order of their required processing times, NORA algorithm which EDF strategy is adopted may not produce minimum total error. Therefore, in this paper, an online algorithm is proposed to minimize total error for the imprecise task system with 0/1 constraint. Then, to compare the performance between the proposed algorithm and NORA algorithm, a series of experiments are performed. As a conseqence of the performance comparison between two algorithms, it has been concluded that the proposed algorithm can produce similar total error to NORA algorithm when the optional tasks are scheduled in the random order of their required processing times but, the proposed algorithm can produce less total error than NORA algorithm especially when the optional tasks are scheduled in the ascending order of their required processing times.

Development of a Window Program for Searching CpG Island (CpG Island 검색용 윈도우 프로그램 개발)

  • Kim, Ki-Bong
    • Journal of Life Science
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    • v.18 no.8
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    • pp.1132-1139
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    • 2008
  • A CpG island is a short stretch of DNA in which the frequency of the CG dinucleotide is higher than other regions. CpG islands are present in the promoters and exonic regions of approximately $30{\sim}60$% of mammalian genes so they are useful markers for genes in organisms containing 5-methylcytosine in their genomes. Recent evidence supports the notion that the hypermethylation of CpG island, by silencing tumor suppressor genes, plays a major causal role in cancer, which has been described in almost every tumor types. In this respect, CpG island search by computational methods is very helpful for cancer research and computational promoter and gene predictions. I therefore developed a window program (called CpGi) on the basis of CpG island criteria defined by D. Takai and P. A. Jones. The program 'CpGi' was implemented in Visual C++ 6.0 and can determine the locations of CpG islands using diverse parameters (%GC, Obs (CpG)/Exp (CpG), window size, step size, gap value, # of CpG, length) specified by user. The analysis result of CpGi provides a graphical map of CpG islands and G+C% plot, where more detailed information on CpG island can be obtained through pop-up window. Two human contigs, i.e. AP00524 (from chromosome 22) and NT_029490.3 (from chromosome 21), were used to compare the performance of CpGi and two other public programs for the accuracy of search results. The two other programs used in the performance comparison are Emboss-CpGPlot and CpG Island Searcher that are web-based public CpG island search programs. The comparison result showed that CpGi is on a level with or outperforms Emboss-CpGPlot and CpG Island Searcher. Having a simple and easy-to-use user interface, CpGi would be a very useful tool for genome analysis and CpG island research. To obtain a copy of CpGi for academic use only, contact corresponding author.

Pressor Action of Physostigmine in the Rabbit (토끼에 있어서의 Physostigmine의 혈압상승작용)

  • Kim, Je-Bong
    • The Korean Journal of Pharmacology
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    • v.26 no.2
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    • pp.101-111
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    • 1990
  • The effect of physostigmine (PS), which has been shown to act on the muscarinic receptors in the brains of the rat, dog and cat, on the arterial blood pressure (BP) was investigated in urethane-anesthetized rabbits. Intravenous (iv) PS, $25{\sim}300\;{\mu}g/kg$, caused little change in BP. However, after treatment of rabbits with either of chlorisondamine (CS), hexamethonium, intracerebroventricular (icv) clonidine, icv xylazine and icy reserpine iv PS produced a pressor response. Spinalization of the rabbit also caused iv PS to increase BP. The pressor effect of iv PS in CS-treated rabbits was markedly reduced after prazosin or pirenzepine. Iv PS inhibited the pressor response to McN-A-343 in CS-treated and in spinal rabbits; alternately during the infusion of McN-A-343 iv PS failed to produce the pressor response. The pressor response to DMPP was not affected by iv PS. Icv PS, $12{\sim}200\;{\mu}g/kg$, produced a pressor response which was accentuated after CS-treatment. This pressor effect was inhibited, though not complete, by prazosin or by pirenzepine. A simultaneous treatment of rabbits with both $[Sar^{1},\;Ala^{8}]-angiotensin$ II, an angiotensin II antagonist, and prazosin or pirenzepine almost completely abolished the pressor effect of icv PS, whereas the angiotensin II antagonist did not enhance the inhibitory effect of pirenzepine and prazosin on the pressor response to iv PS . Icv pirenzepine blocked the pressor response to icv PS without affecting that to iv PS. The present results show that the pressor response to iv PS in CS-treated and in spinal rabbits arises from stimulation of the muscarinic receptors in the sympathetic ganglia, whereas the pressor response by icv PS via activation of the muscarinic receptors in the brain which causes an enhancement in the outflow of sympathetic discharge and angiotensin. The results also suggest that iv PS is unable to produce a pressor response in the rabbit unless the sensitivity of the gangionic muscarinic receptors is altered by ganglionic nicotinic blockade, by the decrease of central sympathetic outflow on the sympathetic ganglia or by spinalization.

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Oestrogenic Activity of Parabens in Uterotrophic Assay (자궁비대시험 연구에서 에틸, 프로필, 이소프로필, 부틸, 이소부틸 파라벤의 내분비독성)

  • Jo Eun-Hye;Jung Ji-Youn;Park Cheol-Beom;Park Sun-Hee;Shim Yhong-Hee;Kang Dae-Hyuck;Lee Sung-Ho;Yu Jong-Hoon;Kim Sun-Jung;Lee Sung-Hoon;Park Jung-Ran;Lee Yong-Soon;Kang Kyung-Sun
    • Journal of Food Hygiene and Safety
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    • v.21 no.2
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    • pp.118-128
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    • 2006
  • This study was conducted to determination of the endocrine distruptor function of 'Parabens' by dosing ethyl paraben, propyl paraben, isopropyl paraben, butyl paraben and isobutyl paraben to the immature SD rats. 18 groups were given vehicle control group, negative control group (Dibutyl phthalate), postive control group ($1'7-{\alpha}$ Ethynylestrdiol) and each paraben groups involved 3 dose level. Rats were injected with 62.5, 250 and 1,000mg/kg from postnatal day 19 till 21 once a day in subcutaneous and a total 3, times. There was no treatment related death. but, subcutaneous nodule, edema, alopecia and scrub formation on injection site was observed. These signs was become worse in high dose level. these signs was cause from physical stimulation by test substance which parabens were mix with com oil as vehicle. In the analysis of organ weights, absolute and relative weights of brain, spleen, liver, thymus, heart, kidneys, adrenals, ovaries and vagina were no difference with control group. but, wet and blotted weight of uterus was increased in every high dose parabens treat group. Especially, all dose level of isobutyl paraben was showed increment of uterus weight. uterus dilatation of parabens treated group was observed in gross anatomic pathology and these result was agree with wet and blotted weight of uterus. In the result of this study, estrogenic effect as endocrine distruptor was observed in ethyl paraben, propyl paraben, isopropyl paraben, butyl paraben and isobutyl paraben. and it was considered isobutyl paraben has highest estrogrnic effect under the condition of this study.

Effects of n-Hexane Fraction of Angelica acutiloba on Antioxidative System and Lipid peroxidation in Ethanol-Induced Hepatotoxicity of rats (일당귀 n-hexane분획이 에탄올을 투여한 흰쥐의 항산화계 및 지질과산화에 미치는 영향)

  • Choo Myung-Hi;Choi Hyun-Suk;Seo Young-Nam;Lee Myung-Yul
    • Food Science and Preservation
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    • v.11 no.3
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    • pp.364-372
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    • 2004
  • To investigate antioxidative effects of n-hexane fraction of Angelica acutiloba on the ethanol-induced hepatotoxicity of rats, Sprague-Dawley rats weighing 100 $\pm$ 20 g were divided into 5 groups; normal group(NOR), ethanol(10 mL/kg, 35$\%$) treated group(CON), n-hexane fraction of Angelica acutiloba 70 mg/kg treated group(Al), n-hexane fraction of Angelica acutiloba 70 mg/kg and ethanol treated group(A2) and n-hexane fraction of Angelica acutiloba 140 mg/kg and ethanol treated group(A3), respectively. The antioxidative activities of ethanol extract of Angelica acutiloba in vitro were decreased in order of n-hexane > ethylacetate > chlorofonn > n-butanol (>) water fraction. The growth rate and feed efficiency rate decreased by ethanol were gradually increased to the adjacent level of the normal group by administering n-hexane fraction of Angelica acutiloba. It was also observed that the activities of SOD of liver, ALT and AST of serum increased by ethanol were markedly decreased in n-hexane fraction of Angelica acutiloba administered group, and not in activites of XO, catalase, as compared with the control group. The depleted content of GSH by ethanol was increased adjacent to normal level by administering n-hexane fraction of Angelica acutiloba. as a dose-dependent manner. These results suggested that n-hexane fraction of Angelica acutiloba has a possible protective effect on the ethanol-induced hepatotoxicity of rats.

Development of the Whole Body 3-Dimensional Topographic Radiotherapy System (3차원 전신 정위 방사선 치료 장치의 개발)

  • Jung, Won-Kyun;Lee, Byung-Yong;Choi, Eun-Kyung;Kim, Jong-Hoon;An, Seung-Do;Lee, Seok;Min, Chul-Ki;Park, Cham-Bok;Jang, Hye-Sook
    • Progress in Medical Physics
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    • v.10 no.2
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    • pp.63-71
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    • 1999
  • For the purpose of utilization in 3-D conformal radiotherapy and whole body radiosurgery, the Whole Body 3-Dimensional Topographic Radiation Therapy System has been developed. Whole body frame was constructed in order to be installed on the couch. Radiopaque catheters were engraved on it for the dedicated coordinate system and a MeV-Green immobilizer was used for the patient setup by the help of side panels and plastic rods. By designing and constructing the whole body frame in this way, geometrical limitation to the gantry rotation in 3-D conformal radiotherapy could be minimized and problem which radiation transmission may be altered in particular incident angles was solved. By analyzing CT images containing information of patient setup with respect to the whole body frame, localization and coordination of the target is performed so that patient setup error may be eliminated between simulation and treatment. For the verification of setup, the change of patient positioning is detected and adjusted in order to minimize the setup error by means of comparison of the body outlines using 3 CCTV cameras. To enhance efficiency of treatment procedure, this work can be done in real time by watching the change of patient setup through the monitor. The method of image subtraction in IDL (Interactive Data Language) was used to visualize the change of patient setup. Rotating X-ray system was constructed for detecting target movement due to internal organ motion. Landmark screws were implanted either on the bones around target or inside target, and variation of target location with respect to markers may be visualized in order to minimize internal setup error through the anterior and the lateral image information taken from rotating X-ray system. For CT simulation, simulation software was developed using IDL on GUI(Graphic User Interface) basis for PC and includes functions of graphic handling, editing and data acquisition of images of internal organs as well as target for the preparation of treatment planning.

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