• The Journal of Korean Society for Radiation Therapy
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• v.34
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• pp.51-60
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• 2022

Objectives: The purpose is to evaluate dosimetric performance and delivery efficiency of VMAT with Halcyon LINAC for double target spine SBRT Materials and Methods: 12 patients with spine oligometastases were retrospectively studied. Single-isocenter spine SBRT plans was established using Halcyon® with Dual Layer MLC and Truebeam® with High Definition MLC. All patients' plans were created in Eclipse TPS through the identical conditions and optimization. C.I, H.I, G.I (Gradient Index), maximal and volumetric doses to spinal cord and low dose area were evaluated for comparison of both plans. Also, total MU and BOT(Beam On Time) were evaluated. Results: Halcyon plans was no Statistical differences in C.I and H.I. However, the average of G.I was 4.64 for Halcyon, which decreased to 5.5% compared to Truebeam (P<0.001). Halcyon plans demonstrated statistically significant reduced G.I. The average of 50% and 25% isodose volume was 487.56 cc (-3.82%, P<0.001), 1859.45 cc (-4.75%, P<0.001) in Halcyon, respectively. Significantly reduced low dose spill were observed in Halcyon plans. In the evaluation of the spinal cord, the average of Dmean and V10 of Halcyon plans in the sample group with an overlap volume of less than 1 cc was 6.802 Gy (-3.504%, P=0.067), 5.766±1.683 cc (-8.199%, P=0.002), respectively. Halcyon plans demonstrated statistically significant reduced D_mean and V10. For delivery efficiency, MU and BOT(maximum dose rate for each machine), on average, increased in Halcyon plans. However, the average of BOT(800MU/min for each machine) was 648.33 sec for Halcyon (-1.74%, P<0.001). Conclusion: Halcyon plan for double-target spine SBRT demonstrated advantages in the low dose area with a steep dose gradient, while having dosimetrically equivalent target dose distribution and spinal cord protective effect. As a result, Halcyon LINAC produced a dosimetrically improved plan for double-target spine SBRT.

• Tuberculosis and Respiratory Diseases
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• v.49 no.4
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• pp.441-452
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• 2000

Background : It is well known that the prevalence of lung cancer is higher in idiopathic pulmonary fibrosis (IPF) patients than in the general population. This high prevalence is explained by the concept of 'scar carcinoma'. There have been several reports on the prevalence of histologic typo of lung cancer in IPF with conflicting results. Despite of the high smoker rate in almost all previous reports, none considered the smoking history of patients. Therefore we performed a separate studies on fibrosis associated lung cancer and smoking associated lung cancer. The purpose of this study is to investigate the proportion of lung cancer in IPF that is fibrosis associated and to determine the most common histologic type in fibrosis associated lung cancer in IPF. Method : A retrospective review of medical records and radiologic studies was performed for cases of lung cancer with IPF. We investigated smoking history, sequence of diagnosis of lung cancer and IPF, histologic type of lung cancer and the cancer location, especially whether the location is associated with fibrosis. To evaluate the proportion of fibrous associated lung cancer, the lung cancer in IPF were categorized according to the presence of fibrosis at cancer location. Results : Fifty seven patients were subjects for this analysis. Six (11%) cases were diagnosed as lung cancer during follow-up for IPF, and both diseases were diagnosed simultaneously in the others. Ninety four percent of patients were smokers and the average smoking amount was 47.1$\pm$21.9 pack-year. Among the patients with IPF and lung cancer, 42(80.8%) cases were considered as "fibrosis associated". The remainder was "not fibrosis associated" and probably was due to smoking etc. Although the most frequent histologic type was squamous cell carcinoma as a whole, adenocarcinoma was the prominent histologic type in "fibrosis associated lung cancer." Conclusion : Considering the proportion of "fibrosis not associated lung cancer" in the patients with IPF and lung cancer, significant proportion of lung cancer in IPF may not be fibrosis induced. This may influence the distribution of histologic type of lung cancer in IPF.

• Journal of Technologic Dentistry
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• v.10 no.1
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• pp.159-169
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• 1988

Fixed prosthetic appliance is the restorations of damaged teeth with cast metal or porcelain, and of replacing missing teeth with fixed, or cemented prosthesis. Successfully treating a patient by means of fixed prosthodontics requires the thoughtful combination of dentist and dental laboratory technician. In order to know the satisfaction of dentisits about fixed prosthetic appliances-porcelain, precious and non precious metal-, this study was conducted for 69 practicing dentisis in Pusan during Fed. to Mar. 1988 using a questionnaire method and was analyzed by the use of percentage, $X^2$-test The results are obtained as follow: 1. General characteristics of the respondents, The rate of age distribution of practcing dentists responded was as follow : 31$\sim$35 age group is 29.0%, 51$\sim$55age group 18.8%, 41$\sim$45 age group and 46$\sim$50 group each 11.6%, 36$\sim$40 age group and 56$\sim$60 age group 8.7%, over 60 age group 7.3%, below 30 age group 4.3% respectively. The tate of term of practice experience distribution of dentists responded was as follow : 6$\sim$10 year group 26.1%, 25$\sim$25year group 18.8%, 11$\sim$15 years group and 16~20 years group each 13.0%, below 5 years group and over 30 years group each 10.2%, 26$\sim$30 years group 8.7% in order. The rate of respondents’ degree was follow : bachelor group 81.2%, doctor group 13.0%, master group 5.8% in order. The rate of respondents’completed medical specialist course was as follow : non-complete group 75.4%, complete group 24.6%. The rate of having own laboratory in respondents’clinic was as follow : no having own laboratory group 58.0%, having own labiratory group 42.0% The rate of being lab. technician in respondent;s clinic was as follow: non-being lab. technician group 91.3%, being lab. technician group 8.7%. The rate of transactional commercial dental lab. numbers was as follow : I dental lab. group 40.6%, 2 dental lab. group 30.4%, 3 dental lab. group 20.3%, production at own lab. group 8.7% 2. Cognitions about the respondent's job, About cognition of patient numvers, there were neither many nor few group 62.3%, few group 17.4%, many group 15.9%, too many group 4.4% in order.(P<.01) As compared with the ratio of dentists to patient prothetic treatment, there were moderate level group 46.4%, high level group 33.6%, low level group 18.8% in order.(P<.01) By job satisfaction of respondents, the highest percentage group was satisfied group 44.9%, neither astisfied nor disstified group 33.3%, dissatisfied group 14.5%, much satisfied group 7.3%(P<.01). As compared with the level of prosthetics price, the were moderate level group 71.0%, low level group 23.2%, high level group 5.8%(P<.01) 3. Satisfaction and assessment of dissatisfied factor of the fixed prosthetic appliance, As compared with the satisfaction of al prosthetic appliance, there were neither satisfied nor dissatisfied group 59.4%, satisfied group 20.3% dissatisfied group 18.8%, much satisfied group 1.5% in order.(P<.01). About precious and non precious metal crown and bridge, there were neither satisfied nor dissatisfied group 60.9%, satisfied group 24.6%, dissatisfied group 11.6%, much satisfied group 2.9% in order.(P<.01) The reat of respondent;s satisfaction about porcelain crown and bridge was as follow : neither satisfied nor dissatisfied group 43.5%, dissatisfied group 33.3%, satisfied group 21.7%, much satisfied group 1.5%(P<.01). The rate of respondent's dissatisfied factor item of precious and non precious metal crown and bridge was as follow : inadequate margin fit item 39.1% respondent, inadequate occlusion item 24.6%, inadequate adaptation item 23.2%, poor anat omic form item 15.9%, inadequate contact item 31.9%, improper polishing item 4.4%, the rest item 11.6% respectively. The rate of respondent's dissatisfied factor item of porcelain crown and bridge was as follow : inadequate margin fit item 52.2%, inadequate occlusion item 2.9%, inadequate adaptation item 10.1%, poor anatomic form item 11.6%, improper polishing item 1.5%, shade mismatching item 71%, the rest item 7.2% respectively. The rate of cognition of respondents’ about cause of dissatisfied factor on fixed prosthetic appliance by item was as follow : deficiency of sincerity item 55.1%, deficiency of knowledge about work item 47.8%, deficiency of experience item 15.9%, poor quality of using material item 5.8%, the rest item 2.9% respectively.

• Journal of Korean Society of Forest Science
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• v.86 no.2
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• pp.186-199
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• 1997

The soils derived from granite gneiss occupy almost one third of the land area in Korea. The soils under forest vegetation, formed on granite gneiss, in Sun chon-shi, Chollanam-do in southern part of Korea, were studied to evaluate the weathering and the transformation of primary minerals into secondary minerals, clay minerals. The studied soils contained large amounts of ferromagnesian minerals, weathered biotites and were well weathered, strongly acid and low in organic matters and in ration exchange capacity. The clay contents in the Bt horizon were almost two times higher than those in the C horizon. The O horizon had a thin layer which consisted of a little decomposed plant components with a granic fabric and high porosity, and showed the micromorphological characteristics of moder humus. The related distribution pattern of the E horizon were enaulic and large amounts of silts and small amounts of sand grains were another characteristics of the E horizon. The most striking micromorphological features were multilaminated clay coating and infillings in the voids in the Bt and C horizons, and generally limpid ferriargillans ejected from the biotites and imparted red color to the soils in the Bt horizon. High clay contents in the Bt horizon was not only due to clay translocation, but also due to intensive in situ mineral weathering in this horizon. The most significant pedogenic process, revealed by the petrographic microscope and SEM, was the formation of iron oxides from biotites, the formation of tubular halloysites and the weathering models of biotites; wedge weathering and layer weathering. The thick coating on the weathering biotites showed the characteristics of the weathering process and the synthetic hematites were revealed in clays by TEM. Total chemical analysis of clays revealed extensive loss of Ca, and Na and the concentration of Fe and Al. Mineralogical studies of clays by XRD showed that micas were almost completely weathered to kaolinite, vermiculite-kaolinite intergrade, hematite, gibbsite, while halloysites from other primary minerals. Some dioctahedral mica appeared to be resistant in the soils. Parent rock of the soils contained a considerable amounts of biotites and this forest soils showed especially a dominant characteristics of biotite weathering.

• Korean Journal of Environmental Agriculture
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• v.34 no.2
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• pp.69-76
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• 2015

BACKGROUND: Contamination of soils by heavy metals is the serious environmental problem. In particular, industrial processing is one of the main sources of heavy metal contamination. The objective of this study was to investigate the distribution characteristics of heavy metals in soils collected from industrial complex. METHODS AND RESULTS: In this study, the soil contamination and enrichment factor (EF) of heavy metals were investigated in three national industrial complexes such as Yeosu, Ulsan and Sihwa Banwal industrial complexes. The target heavy metals includes Cd, Cu, As, Hg, Pb, Cr, Zn, and Ni. The results showed that the contents of Cd, Hg, Pb, Zn and Ni in Yeosu and the contents of Cu, As and Cr in Sihwa Banwal were higher than in any other industrial complex. The results of principal component analysis(PCA) in Yeosu, Ulsan and Sihwa Banwal complex could be explained up to approximately 81.4, 69.1 and 70.9% by two factor, respectively. Enrichment factors of Cd, Pb and Zn in all the investigated industrial complexes were above 1.0 that was the value judged to be a high contamination. And EF of Cr was above 1.0 in Sihwa Banwal complex. EF of Zn in all sites was generally high from the other heavy metals. CONCLUSION: Therefore, soils maybe significantly affected by heavy metals (especially, Cd, Pb and Zn) present in the emissions from industrial complexes.

• Korean Journal of Plant Resources
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• v.30 no.2
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• pp.213-218
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• 2017

Rice is the staple food of at least half of the world's population. Due to global warming, the weather is difficult to forecast nowadays. Therefore, it is necessary to breed various breeding to respond to such changes in the environment. This study was conducted to analyze the QTL about plant form, culm length, ear number and ear length by using 120 lines by anther culture, a cross between the Indica variety Cheongcheong and Japonica variety Nagdong. DNA marker was selected on the QTLs gene, and the following results were obtained. CNDH (Cheongcheong Nagdong Doubled Haploid) lines frequency distribution table curves about culm length, ear number and ear length exhibited showed a continuous variation close to a normal distribution. QTL analysis result, on culm length qPlL1-1 and qPlL1-2 were detected on the chromosome 1 and qPlL5 was detected on the chromosome 5. However, on ear length qPL2, qPL3 and qPL10, were detected on the chromosome 2, 3 and 10, while on ear number qPN1-1 and qPN1-2 were detected on the chromosome 1, qPN9 was detected on the chromosome 9. The QTLs related to culm length was found to chromosomes 5 and LOD scores were 3.81. The QTLs related to ear length was found to chromosomes 2 and 3 LOD scores were 7.13 and 3.20. The QTLs related to ear number was found to chromosome 9 and LOD scores were 4.27. Twenty two (22) Japonica cultivars and 12 Indica cultivars were analyzed polymorphisms, using selected 9 markers from the result about plant form analysis. RM5311, RM555 and RM8111 about the culm length, the ear length and number of ear were selected on the standard of Cheongcheong and Nagdong. Each rate of concordances about the culm length, the ear length and number of ear are 44.11%, 41.17% and 44.11%.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.3
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• pp.175-194
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• 2014

This study attempts to identify the spatial distributions of Achnanthes convergens, and elucidate the environmental factors that affect the Periphyton diatom habitat. Data in 250 points of Nakdong river basin are collected between April(primary) and September(secondary) 2012, with the National Institute of Environmental Research's support. We define "clean area" over 10% of Achnanthes convergens appearance, and the others as "non-clean areas". Spatial statistics of Kriging, Hotspot, LISA are used in this study. Results show that 1) 56 points are identified as clean areas in the primary survey, while 41 points are discovered in the following survey; 2) using water quality variables, density of turbidity(clean $101.83{\mu}s/cm$; non-clean $598.48{\mu}s/cm$) and conductivity(clean 1.95 NTU; nonclear 5.58 NTU) are five-fold lower in clean-areas; 3) Habitat and Riparian Factors in Nakdong basin illustrate that natural sand bar, diversity of velocity, sediment condition, levee material, riverside land affect Achnanthes convergens; 4) Hotspots of Achnanthes convergens are located in watersheds, including upper Andong Dam, upper Imha dam, Wi-cheon, Miryang river, Nam river and Hwang river whereas mainstream/downstream of Nakdong river and Keumho river watershed are shown as coldspots.

• Journal of the Korean Geographical Society
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• v.38 no.3
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• pp.426-443
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• 2003

Electronic Commerce (EC) has been at the center of discussion as a symbol of the integration of unprecedentedly developed Information and Communication Technologies (ICTs) and traditional commerce. In spite of much attention to EC, the research from a spatial perspective has not proliferated yet. EC was regarded to have aspatial characteristics based on the expectation for a global expansion of business activities in a digital economy. This paper attempts to figure out the spatial characteristics of public Business-to-Business electronic marketplaces (public B2B e-MPs), as one of the most evolving forms of B2B EC, regardless of the low proportion in B2B EC at present. Many of the firms operating public B2B e-MPs in Korea were located in Seoul, especially in Gangnam-gu. The analysis of three spatial indices showed their extreme spatial concentration. The analysis on the location factors of Public B2B e-MP firms in Korea demonstrated that location factors of public B2B e-MP firms were differentiated by regional groups: Gangnam-gu, Seoul except Gangnam-gu, and the provinces. It was againt an initial extreme expectation that the firms relevant to B2B EC will not care about physical locations because they mainly do businesses in electronic space. The differences between those in Gangnam-gu and in the provinces were strikingly prominent. Such differentiated location factors by region were closely related to the different attributes of the public B2B e-MPs by region. In conclusion, public B2B e-MPs are not irrelevant to physical space and physical proximity, at least at a current stage. Customized spatial strategies are required for successful online businesses.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.20 no.2
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• pp.78-91
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• 2015

Macrobenthic community was studied at 87 stations including intertidal and subtidal area in Yoja Bay, south coast of Korea in summer season of July 2001. Duplicate sediment samples were taken using a van Veen grab ($0.1m^2$) in each station. Mud facies of the sediments were widly distributed in the bay. And relatively high content of sand was shown in the Bulgyo-cheon stream estuary. A total of 274 species was occurred with a mean density of $2,346ind./m^2$ and a mean biomass of $78.2g/m^2$. The polychaetes were species- and density-dominant faunal group with a total of 122 species (44.5% of the total number of species), and mean density of $1,543ind./m^2$ (65.8% of the mean density). Meanwhile, molluscs were biomass-dominant faunal group with $44.4g/m^2$. Bio-Env. analysis showed that the combination of bottom salinity and sand content of the surface sediments was highly correlated to the major macrobenthic communities. The macrobenthic species number, decreasing toward inner bay from mouth of the bay, was significantly correlated to the sediment environmental variables and bottom water salinity. The spatial distribution of abundance showed significant correlation to the sand and mud contents and mean grain size of the surface sediments. Major dominant species were Minuspio japonica (polychaete) with a mean density of $1,167ind./m^2$ at upper part of the bay where salinity was low and Eriopisella sechellensis (amphipod) with $152ind./m^2$ in central part of the bay. Species diversity (H') was $3.0{\leq}$ in the mouth part of the bay and ranged 2.0-3.0 in the inner part of the bay, which showed a significant positive correlation to bottom salinity. Total number of species also showed significant correlations to the sediment composition and bottom salinity. Based on the cluster analysis the macrobenthic community of the bay was classified into five station groups from the bay mouth toward the inner part of the bay depending on the species composition. From the SIMPER analysis Minuspio japonica, Eriopisella sechellensis and Sternaspis scutata mainly contributed to the classification of station group. These results suggested that the macrobenthic communities of the bay were mainly influenced by bottom salinity together with sediment composition, and that the studies of spatial distributions of major dominant species and benthic communities should be conducted continuously to monitor the Yeoja Bay benthic environment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.2
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• pp.202-208
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• 1995

Puksin Bay located in the northwestern pan of Tongyeong, Korea has been contaminated by municipal wastewaters. In Puksin Bay, red tides have occured almost every year since the early 1980's. This experiment was carried out two times in a month in the winter in 1990, the summer' 1991, and the winter in 1994 so as to clarify the distribution marine bacteria and coliform groups in Puksin Bay. The water quality of Puksin Bay was not only move polluted than that of any other costal area around Tongyeong, but also its water quality was investigated to keep going bad. Viable cell counts in Puksin Bay were $4.9\times10^3/ml$ in 1990's winter, $3.6\times10^6/ml$ in 1991's summer, and $2.1\times10^4/ml$ in 1994's winter. The variation of seasonal total and fecal coliform MPN/100ml in Puksin Bay were $6.7\times10^2\;and\;2.6\times10^2$ in 1990's winter, $1.5\times10^4$ and $5.4\times10^3$ in 1991's summer, and $1.5\times10^3$ and $5.6\times10^2$ in 1994's winter, respectively. The changes of stational total coliform MPN/100m1 from station 1 to station 8 in Puksin Bay were 95,000, 1600, 1,000, 182, 151, 94, 43 and 13 in winter, and 110,000, 29,000, 2,400, 4,100, 1,700, 1,700, 810 and 150 in 1991's summer, and 3,381, 1928, 1582, 256, 161, 59 and 23 in 1994's winter. During the study period, the number of viable cell was ranged from $10^4\;to\;10^7/ml$ and 307 bacteria strains were isolated from Puksin Bay. The dominant species were Acinetobacter spp. 86 $(28.3\%)$, Pseudomonas spp. 51 $(16.6\%)$, Flavobacterium spp. 41 $(13.4\%)$, Escherichia coli 36 $(11.7\%)$, and Vibrio spp. 27$(8.8\%)$. The results obtained in this study indicate that this bay is getting to contaminate far more with municipal wastewaters and cultivation of the shellfish and finfish in this bay is not proper. When municiple wastewaters keep flowing into this bay, any other coastal area around Tongyeong may be contaminated.