• Korean Journal of Environment and Ecology
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• v.31 no.6
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• pp.508-519
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• 2017

There have been many studies on monitoring of biodiversity changes and preservation of Gwangneung Forest Biosphere Reserve (GFBR) in South Korea in recognition of the rare ecosystem that has been preserved for a long period. However, there are few studies on diversity and community characteristics of benthic macroinvertebrates as an indicator of stream health of GFBR. The purpose of this study was to assess the water quality of Bongseonsa Stream that penetrated through Gwangneung Forest and the nearby torrents by analyzing the benthic macroinvertebrates community during April to September 2016. The investigation collected a total of 114 species of benthic macroinvertebrates belonging to 56 families, 17 orders, 8 classes, and 5 phyla from the Bongseonsa Stream and Kwangneung Stream. Ephemeroptera and Trichoptera were the largest groups in species diversity with 30 species (32.3%) and 16 species (17.2%), respectively, and Tubificidae sp., Baetis fuscatus, Antocha KUa, and Cheumatopsyche brevilineata, which usually habit in contaminated streams, appeared frequently. Among the feeding function groups, the gatherers and hunters appeared relatively frequently, and the shredders and scrapers appeared frequently in the torrents. Among the habitat oriented groups, the clingers and burrower appeared more frequently and represented the microhabitats in the shallow areas. The result of the analysis of benthic macroinvertebrates community showed that the dominant index was $0.48{\pm}0.10$ in average while it was lowest with 0.33 in GS 8 of the Gwangneung Forest torrent and highest in BS 1 of Bongseonsa Stream. The diversity and richness indices were inversely proportional to the dominant index and were 2.53 and 4.22, respectively, in GS 8 where the dominant index was low. The result of the analysis of community stability showed that area I, which had high resistance and restoration, was high in Bongseonsa Stream while the area III, which had low resistance and restoration, was high in Gwangneung Forest, indicating that the water system in Gwangneung Forest had a wider distribution of specifies sensitive to agitation. The biological water quality assessment showed ESB of $50.88{\pm}17.69$, KSI of $1.11{\pm}0.57$, and BMI of $78.55{\pm}11.05$. GS 8 of Gwangneung Forest torrent was judged to be the highest priority protective water area with the best water environment and I class water quality with ESB of 63, KSI of 0.55, and BMI of 89.9. On the contrary, BS 1 of Bongseonsa Stream was judged to be the high priority improvement area that had the lowest water quality rating of III with ESB of 25, KSI of 2.13, and BMI of 62.7. Although the diversity of water beetle was higher in the water system of nearby Bongseonsa Stream than the water system inside the Gwangneung Forest, the annual community structure appeared to have distinct differences.

• Journal of the Mineralogical Society of Korea
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• v.16 no.2
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• pp.135-149
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• 2003

Domestic zeolite ores are mostly composed of Ca-type clinoptilolite, accompanying a little amounts of mordenite. However, other types of zeolite ores rich in ferrierite, heulandite, or mordenite are less commonly found. Based on the quantitative XRD analysis, zeolite contents are determined to be nearly 50∼90 wt%. Impurities (mostly ＞ 10 wt%) in the zeolite ores chiefly consist of quartz, feldspar, smectite, and opal-CT. The determined CEC values ($CEC_{AA}$ ) of powdery samples (grain size: < 125 $\mu\textrm{m}$) of zeolite ores by the Ammonium Acetate method are mostly higher than 100 meq/100 g. Some zeolites from the Guryongpo area, corresponding to the clinoptilolite ore, are measured to be dominantly high in CEC values ranging 170∼190 meq/100 g. Cation exchange property of the zeolite ores varies greatly depending on the types or zeolite species present in the ores. Despite of the lower grade in zeolite content, the $CEC_{AA}$ of ferrierite ore is comparatively high. Compared to this, the $CEC_{AA }$ of heulandite ore is very low, though the zeolite ore exhibits the highest grade ranging up to about 90 wt%. In addition, the CEC values calculated theoretically from the framework composition of clinoptilolite-heulandite series are not consistent with those determined by the cation exchage experiment. The measured $CEC_{AA}$ of clinoptilolite ores are generally higher than those of heulandite ores. This may be due to the higher Ca abundance in exchangeable cation composition and the presence of probable stacking faults in heulandite. The variation of $CEC_{CEC}$ is roughly proportional, though not strictly compatible, to the zeolite contents in clinoptilolite ores. It seems to be caused by the fact that the $CEC_{AA}$ of clinoptilolite locally varies depending on crystal-chemical diversity, i. e., the variation in framework composition (Si/Al) and exchangeable cation composition (especially, the contents of Ca and K). In addition, the determined CEC values ($CEC_{MB}$ ) of zeolite ores by the Methylene Blue method are much higher than those calculated from smectite contents. It suggests a probable reaction of Methylene Blue ion ($C_{16}$ $H_{18}$ $N_3$S+) with larger-pore zeolites than clinoptlolite-heulandite series, i.e., ferrierite and mordenite as well as with smectite. This can be supported by the fact that the ferrierite ore accompanying little amount of smectite has the highest value in CE $C_{MB}$ .

• Journal of Gastric Cancer
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• v.9 no.4
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• pp.200-206
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• 2009

Purpose: The incidence of upper gastric cancer and especially the diffuse type have increased in western countries. The aim this study was to investigate the chronologic changes of the clinicopathological features and survival rates of Korean upper gastric cancer patients. Materials and Methods: 1,638 gastric cancer patients who underwent gastrectomy were included in this study and they were divided into two groups; the 1990's (1991~1999, n=987) and the early 2000's (2000~2003, n=651). We evaluated the differences of the clinicopathologic features and the factors that affected the survival rates by univariative and multivariative analysis. Results: The older age (>60) patients increased from 42.7% to 50.7% respectively. Being overweight (body mass index$\geq$23) also increased from 31.5% to 43.2%. For the pathology, the incidence of stage Ia gastric cancer increased (29.8% to 44.5%) and the incidence of stage IV gastric cancer decreased (23.5% to 11.8%). Yet there was no difference according to the WHO classification, Lauren's classification and the location of tumor between the groups. The 5 year survival rates increased 67.7% to 83.7%, according to the group. Multivariative analysis showed that the odd ratios of the early 2000s was 0.715 (95% CI; 0.555~0.921) as compared to that of the 1990s. Conclusion: There were no changes of the clinicopathologic features, like the pattern in western countries, although the incidence early gastric cancer, old age patients and overweight patients increased. The survival rate of early 2000s was better that that of the 1990s.

• Journal of Gastric Cancer
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• v.5 no.4 s.20
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• pp.281-287
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• 2005

Purpose: This study was conducted to evaluate the effectiveness and the role of post-operative adjuvant chemoradiation therapy in a stage-II (UICC, 1997) primary gastric cancer. Materials and Methods: From September 1994 to December 2004, 954 stage-II gastric-cancer patients were seen, and all of them underwent a curative resection with extensive (D2) lymph-node dissection. The chemotherapy consisted of fluorouracil $(400mg/m^2)$ plus leucovorin $(20mg/m^2)$ for 5 days, followed by 4,500 cGy of radiotherapy for 5 weeks with fluorourcil and leucovorin on the first 4 days and the last 3 days of radiotherapy. Two five-day cycles of chemotherapy were given four weeks after the completion of radiotherapy. The Kaplan-Meier method was used to estimate the survival rates. To assess the importance of potential prognostic factors, we performed univariate and multivariate analyses using a log-rank test and Cox's proportional hazards regression model. A P value <0.05 was considered significant. Results: Univariate analysis revealed that age, tumor size, gross type, surgical method, and postoperative adjuvant therapy had statistical significance. Among these factors, age, surgical method, tumor size, surgical method, and postoperative adjuvant therapy were found to be independent prognostic factors by using a multivariate analysis. The postoperative adjuvant chemotherapy group and the chemoradiation therapy group had survival benefit compared to the surgery-only group. However the chemoradiation therapy group had no significant survival benefit compared to the chemotherapy group. Conclusion: The postoperative adjuvant therapy in stage-II gastric-cancer patients had significant benefit. Therefore, postoperative adjuvant chemoradiation therapy has an acceptable effect. A large-scale, randomized study is needed to evaluate the effectiveness and the role of postoperative radiation therapy.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3773-3777
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• 2015

Background: This study aimed to establish a nomogram by combining clinicopathologic factors with overall survival of stage IA-IIB cervical cancer patients after complete resection with pelvic lymphadenectomy. Materials and Methods: This nomogram was based on a retrospective study on 1,563 stage IA-IIB cervical cancer patients who underwent complete resection and lymphadenectomy from 2002 to 2008. The nomogram was constructed based on multivariate analysis using Cox proportional hazard regression. The accuracy and discriminative ability of the nomogram were measured by concordance index (C-index) and calibration curve. Results: Multivariate analysis identified lymph node metastasis (LNM), lymph-vascular space invasion (LVSI), stromal invasion, parametrial invasion, tumor diameter and histology as independent prognostic factors associated with cervical cancer survival. These factors were selected for construction of the nomogram. The C-index of the nomogram was 0.71 (95% CI, 0.65 to 0.77), and calibration of the nomogram showed good agreement between the 5-year predicted survival and the actual observation. Conclusions: We developed a nomogram predicting 5-year overall survival of surgically treated stage IA-IIB cervical cancer patients. More comprehensive information that is provided by this nomogram could provide further insight into personalized therapy selection.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.5
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• pp.105-115
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• 2015

This study examined what effect the educational satisfaction level in the grey job project had on the business effectiveness and verified the effect the participant education satisfaction level had on the project business effectiveness ultimately by influencing the job satisfaction. This study utilized the source data of the senior job project old participant status survey of the Korea senior manpower development center which was conducted in 2013, and the non-proportional stratification sample extracting method was used which considered the project type, regional size, and cities/provinces. Sejong City was excluded from the survey target and the survey targeted 2,005 persons except for non-response or response-irrelevant persons concerning this study question. The collected material was analyzed by using SPSS WIN 21.0 program. The frequency and percentage were calculated to apprehend the general characteristic of the study target. Also, the regression analysis was conducted to examine the effect the educational satisfaction level had on the business effectiveness of the senior job project, and the hierarchical regression analysis was conducted in order to examine the mediated effect of the job satisfaction level in the effect the educational satisfaction level had on the business effectiveness of the senior job project. The main result of this study is as follows. First, among the effects the educational satisfaction level had on the business effectiveness, both interest level of educational contents and the job utilization of education had a significant effect on the psychological effect, and the interest level of the educational contents had a significant level on the physical/social effect, and the job utilization of education had a significant effect on the economic effect. Second, in the effect the educational satisfaction level had on the business effectiveness, the job satisfaction level was confirmed the job satisfaction level had a partial mediated effect in the effect the educational satisfaction level had on the psychological/physical/social effect. The job satisfaction level was confirmed the job satisfaction level had a complete mediated effect in the effect the educational satisfaction level had on the economic effect. Also, The job satisfaction level was confirmed the job satisfaction level had a partial mediated effect in the effect the educational satisfaction level had on the business effectiveness. Consequently, the educational contents according with the demand of job participants will have to be developed and the exclusive manpower must be arranged to conduct the education effectively. Also, making participants feel a pride on the job fully will largely contribute to raising the business effectiveness because the job satisfaction level has a positive effect on the business effectiveness.

• Korean Journal of Remote Sensing
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• v.33 no.5_3
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• pp.855-866
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• 2017

Several research cases using remote sensing methods to analyze changes of storage and dynamics of groundwater aquifer were reviewed in this paper. The status of groundwater storage, in an area with regional scale, could be qualitatively inferred from geological feature, surface water altimetry and topography, distribution of vegetation, and difference between precipitation and evapotranspiration. These qualitative indicators could be measured by geological lineament analysis, airborne magnetic survey, DEM analysis, LAI and NDVI calculation, and surface energy balance modeling. It is certain that GRACE and InSAR have received remarkable attentions as direct utilization from satellite data for quantification of groundwater storage and dynamics. GRACE, composed of twin satellites having acceleration sensors, could detect global or regional microgravity changes and transform them into mass changes of water on surface and inside of the Earth. Numerous studies in terms of groundwater storage using GRACE sensor data were performed with several merits such that (1) there is no requirement of sensor data, (2) auxiliary data for quantification of groundwater can be entirely obtained from another satellite sensors, and (3) algorithms for processing measured data have continuously progressed from designated data management center. The limitations of GRACE for groundwater storage measurement could be defined as follows: (1) In an area with small scale, mass change quantification of groundwater might be inaccurate due to detection limit of the acceleration sensor, and (2) the results would be overestimated in case of combination between sensor and field survey data. InSAR can quantify the dynamic characteristics of aquifer by measuring vertical micro displacement, using linear proportional relation between groundwater head and vertical surface movement. However, InSAR data might now constrain their application to arid or semi-arid area whose land cover appear to be simple, and are hard to apply to the area with the anticipation of loss of coherence with surface. Development of GRACE and InSAR sensor data preprocessing algorithms optimized to topography, geology, and natural conditions of Korea should be prioritized to regionally quantify the mass change and dynamics of the groundwater resources of Korea.

• Journal of Korean Society of Transportation
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• v.25 no.4
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• pp.123-133
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• 2007

This study analyzed whether a transit network with hierarchy is efficient or not, and if transit network hierarchy has cost efficiency, then which condition guarantees the efficiency of the transit network hierarchy. The authors modeled the total cost of the transit network and suggested the conditions in which the transit network hierarchy has cost efficiency through comparing the cost of the transit network with and without hierarchy. The efficiency of transit network hierarchy is guaranteed when the travel cost savings induced by using a higher hierarchy transit network is larger than the increasing non-travel cost, which is the sum of access cost, waiting cost, and operating cost, induced by the introduction of a higher hierarchy transit network. This result is consistent with common sense and with the concept of cost and benefit analysis. If a passenger traveling within the area divided by a higher hierarchy transit network uses only a lower hierarchy transit network and the passenger traveling out of the area divided by the higher hierarchy transit network uses both lower and higher hierarchy transit networks, the travel demand using the higher hierarchy transit network is inversely proportional to the square of the line spacing. This means that the transit network becomes more efficient and small increases of travel demand guarantee the efficiency of the transit network hierarchy as the connectivity of the network becomes higher. This result shows that transit networks have economies of aggregation. This study is the first analytical research on transit network hierarchy and is expected to be a basis for numerical research. However, numerical research should complement this study, since analytical research has some limitations for considering a real network.

• Radiation Oncology Journal
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• v.14 no.1
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• pp.53-59
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• 1996

Purpose : Radiation-induced alteration in the immune function is well known phenomenon in cancer patients. Our purpose is to evaluate the extent of immune suppression immediately after mediastinal or pelvic irradiation, which include significant volume of active bone marrow in adults. Materials and Methods'48 cancer patients with mediastinal(N=29) and pelvic irradiation(N=19) were the basis of this analysis. Age ranged from 36 to 76 and mean and median value was 57 years, respectively Sex ratio was 1.3(M: F=27/21). The immunological parameters were the complete blood cell(CBC) with differential cell(D/C) count, T cell subset(CD3, CD4, CD8 CDl9), NK cell test(CDl6, CD56), and serum immunoglobulin(IgG, IgA, IgM) level. Results : The mean value of white blood cell(WBC) was reduced from 7017 to 4470 after irradiation(p=0.0000). In the differential count, the number of lymphocyte, neutrophil, and basophil was markedly reduced with statistical significance(p<0.01) and the number of monocyte was not changed and, on the contrary, that of eosinophil was increased by irradiation. In the lymphocyte subpopulation analysis, the number of all subpopulations, CD3(T cell), CD4(helper T cell), CD8(suppressor T cell), CDl6(NK cell), CDl9(B, cell) was reduced with statistical significance. The mean ratio of CD4 to CD8 in all patients was 1.09 initially and reduced to 0.99 after radiotherapy(p=0.34) , but the proportional percentage of all subpopulations was not changed except CD19(B cell) after irradiation. In the immunoglobulin study, initial values of Ig G, Ig A, and Ig M were relatively above the normal range and the only Ig M was statistically significantly reduced after radiotherapy(p=0.02). Conclusion : Mediastinal and pelvic irradiation resulted in remarkable suppression of lymphocyte count in contrast to the relatively good preservation of other components of white blood cells. But the further study on the functional changes of lymphocyte after radiotherapy may be necessary to conclude the effects of the radiation on the immunity of the cancer Patients.

• Radiation Oncology Journal
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• v.18 no.2
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• pp.85-91
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• 2000

Purpose : The aim of this study is to look for the possible efficacy of postoperative external irradiation for incompletely resected meningiomas. Methods and Materials : From August 198: to January 1997, forty-four patients with intracranial meningioma were treated by postoperative external irradiation. Of the 44 meningiomas, 18 transitional, 13 meningotheliomatous, 6 hemangiopericytic, 4 atypical, 2 fibroblastic and 1 malignant meningioma were identified. We classified all patients into two groups by the histology. The benign group was consisted of the meningotheliomatous, transitional and fibroblastic types. The malignant group was consisted of the atypical, hemangiopericytic and malignat types. In the means of surgery, 37 patients were resected incompletely and 7 patients were managed by biopsy only. After surgery, all patients were received postoperative external irradiation. Radiotherapy was deliverd using Co-60 or 4 MV photon beam to a total dose of 50 to 65 Gy (mean dose 57.4 Gy) with a 1.8 to 2 Gy per fraction. The median follow-up was 48 months (range : 21 $\~$ 101 months). Multivariate analysis of the Influence by age, sex, location, histology and radiation dose on local control has been done using Cox's proportional hazard model. Results : 5-year local control rate was 93.8$\%$ for the benign histology and 51.8$\%$ for the malignant histology (p=0.0110) and overall local control rate at 5 years was 87.4$\%$. The analysis of the prognostic factors, such as age, sex, location, and radiation dose were not significant except for the histology. Conclusion : Adjuvant postoperative external irradiation appears to be significantly improved local control in the patients with incompletely resected meningiomas.