• Journal of Korea Water Resources Association
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• v.51 no.8
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• pp.729-737
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• 2018

This study investigates the sediment processes the Improved-pneumatic-movable weir through laboratory experiments considering changing channel slopes. Experimental results show that the delta migrates towards the weir and the delta height increases as time passes. Moreover, as the delta approaches the weir, the delta migration speed decreases. As the dimensionless delta location increases, the effective height of dimensionless delta and the dimensionless reservoir capacity increases. Therefore, under the same slope conditions, the sediment deposition volume of the delta is small as the channel slope is mild. This means that the channel slope affects the development of the delta in the upstream of the Improved-pneumatic-movable weir. At the beginning of the experiment, the foreset slope is mild. However, the foreset slope of the delta increases with water depth as the delta migrates downstream. Moreover, as the slope is mild, the ratio of delta front length to delta height is close to 1, and the dimensionless delta height and the dimensionless delta migration speed decrease. As the delta height increases, the water depth, the velocity approaching to the weir and the delta migration speed decrease.

• Spatial Information Research
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• v.21 no.1
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• pp.45-52
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• 2013

Recently 3D surveying is recommended to manage underground facilities systematically before refilling of site operation. As the demand of realtime localization increases, cost reduction and consistent data construction which are realizable by using one man surveying method with unmanned target, are necessary for constructing DB of all sorts of the underground facilities with more speediness and correctness. This study sets a goal to develop a new type of surveying target which allows realtime localization to be performed by one man, through making an optimum reflector(triangle, quadrangle, and semispherical shape) by using the retro-reflection principle of optical prism which is being used for surveying currently. The new surveying target makes realtime surveying possible. To check reliability of its data, the accuracy is compared with surveying coordination of total station for each type in a quantitative method. In the result, the usefulness of the reflector for Underground Facilities localization is proved. Thus the foundation for underground DB construction conducted by one man is established for acquisition of 3D location information in more efficient way through using unmanned target.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.4
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• pp.337-344
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• 2000

Germ-line mutations at DNA repair loci confer susceptibility to colon cancer in hereditary non-polypopsis colorectal cancer. Somatic loss of DNA mismatch repair gene has been reported in a large variety of other tumor types. Replication errors(RERs) judged by microsatellite instability(MSI) and its associated mutations have been recognized as an important mechanism in various tumor types. To investigate associations between MSI and oral squamous cell carcinoma, the frequency of MSI using 12 microsatellite markers were analyzed for the series of oral tumors. Of 17 tumors, 8 cases(47%) did not show instability at any of the 12 loci; 5(29%) showed instability at $2{\sim}3$ loci; and 4(24%) showed instability above 4 loci. The 4 cases showing widespread MSI did not differ from those without evidence of instability in terms of age at diagnosis, degree of differentiation, metastasis to lymph node, tumor location or the presence of mutations in the p53 tumor suppressor gene. DCC and D17S 796 were the most frequently detected in MSI analysis. There were no correlation between smoking and MSI frequency, instead, smoking was suggested to increase the mutation rate of p53 and development of oral carcinomas.

• The Journal of Korean Academy of Prosthodontics
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• v.32 no.2
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• pp.327-353
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• 1994

This study was performed to evaluate the effects of number and alignment of implant fixture and various bar designs on the retention of denture and the stress distribution. Six kinds of photoelastic mandibular models and nine kinds of overdenture specimens were designed. A unilateral vertical load was gradually applied on the right first molar to calculate the maximal dislodgement load of each specimen. A unilateral vertical load of 17 Kgf was applied on the right first molar and a vertical load of 10 Kgf was applied on the interincisal edge region. The stress pattern which developed in each photoelastic model was analyzed by the reflection polariscope. The results obtained were as follows: 1. The maximal dislodgement load reversely increased with the distance from the loading point to the implant fixture, while it linearly increased with that from the most posterior implant fixture to the mesial clip. The maximal dislodgement load also increased with the use of a cantilever bar. 2. Under the posterior vertical load, the stress to the supporting tissue of the denture base increased with the distance from the loading point to the implant future. The stress concentration on the apical area of the implant future reversely increased with the distance from the loading point to the implant future. 3. In the overdentures supported by two implant fixtures under the posterior vertical load. the specimen implanted on lateral incisor areas with a cantilever bar exhibited more favorable stress distribution than that without a cantilever bar. The specimen implanted on the canine areas without a cantilever bar, however, exhibited more favorable stress distribution. 4. In the overdentures supported by three implant fixtures. the specimen implanted ell the midline and canine areas exhibited more favorable stress distribution than that implanted oil the midline and the first premolar areas. 5. In the overdentures supported by four implant fixtures. the specimen implanted with two adjacent implant fixtures exhibited more favorable stress distribution than that implanted at equal distance under the posterior vertical load. 6. Under the anterior vertical load, the overdentures supported by three implant fixtures exhibited stress concentration on the supporting structure of the middle implant future. In overdentures supported by two or four implant futures, no significant difference was noted in stress distribution between the types of bars. These results indicate that the greater the number of implant fixtures, the better the stress distribution is. A favorable stress distribution may be obtained in the overdentures supported by two or three implant fixtures, if the location and the design of the bar are appropriate.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.2091-2095
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• 2013

Background: The $7^{th}$ TNM staging is the first authoritative standard for evaluation of effectiveness of treatment of gastric cancer worldwide. However, revision of pN classification within TNM needs to be discussed. In particular, the N3 sub-stage is becoming more conspicuous. Methods: Clinical data of 302 pN3M0 stage gastric cancer patients who received radical gastrectomy in Tianjin Medical University Cancer Institute and Hospital from January 2001 to May 2006 were retrospectively analyzed. Results: Location of tumor, depth of invasion, extranodal metastasis, gastric resection, combined organs resection, lymph node metastasis, rate of lymph node metastasis, negative lymph nodes count were important prognostic factors of pN3M0 stage gastric cancers. TNM stage was also associated with prognosis. Patients at T2N3M0 stage had a better prognosis than other sub-classification. T3N3M0 and T4aN3aM0 patients had equal prognosis which followed the T2N3M0. T4aN3bM0 and T4bN3aM0 had lower survival rate than the formers. T4bN3bM0 had worst prognosis. In multivariate analysis, TNM stage group and rate of lymph node metastasis were independent prognostic factors. Conclusions: The sub-stage of N3 may be useful for more accurate prediction of prognosis; it should therefore be applied in the TNM stage system.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.3
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• pp.48-62
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• 2018

In this study, landslide of debris flow occurred at 51 sites around Daeryounsan located in between Chuncheon-si and Hongcheon-gun during July in 2013 were investigated in field and behavior characteristics of debris flow were analyzed on the basis of records of rainfall and site investigation. According to debris flow types of channelized and hill slope, location and slope angle of initiation and deposit zone, and width and depth of erosion were investigated along entire runout of debris flow. DEM(Digital Elevation Model) of Daeryounsan was constructed with digital map of 1:5,000 scale. Land slide hazard was estimated using SINMAP(Stability INdex MAPping) and the predicted results were compared with field sites where debris flow occurred. As analyzed results, for hill slope type of debris flow, predicted sites were quite comparable to actual sites. On the other hand, for channelized type of debris flow, debris flow occurrence sites were predicted by using stability index associated with topographic wetness index. As analyzed results of 4 different conditions with the parameter T/R, Hydraulic transmissivity/Effective recharge rate, proposed by NRCS (Natual Resources Conservation Service), predicted results showed more or less different actual sites and the degree of hazard tended to increase with decrease of T/R value.

• Korean Journal of Environment and Ecology
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• v.33 no.6
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• pp.695-707
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• 2019

This study was intended to suggest the appropriate vegetation management methodology by analyzing phytosociology for ecotourism resources. We carried out the classification and interpretation of the vegetation structure and the analysis of the relationship between communities and environmental conditions in Pocheon valley, Mt. Gaya. The vegetation in Pocheon valley was composed of 5 communities: Pinus densiflora-Quercus mongolica community, Quercus serrata-Quercus variabilis community, Larix kaempferi-Quercus serrata community, Pinus densiflora-Castanea crenata community, and Salix gracilistyla-Phragmites japonica community. The Quercus serrata-Quercus variabilis community was further segmented into two types according to the differences of composition species and location of habitats. The methodologies that satisfy both the use of nature for ecotourism resources and the sustentation of natural vegetation are as follows: - maintenance the present vegetation (dominance species) by strictly avoiding artificial management in the tree layer; - maintenance of the existing vegetation structure through the artificial management of the usual vigorous tree species when the species in the shrub layer grow up to the subtree layer; and - continued artificial management to maintain high balanced diversity and evenness of various species in shrub and herb layers.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.2
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• pp.55-68
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• 2014

Some infrastructure these days is usually constructed under the ground for it to not interfere the foot-traffic of pedestrians, and thus, it is difficult to visually confirm the accurate location of the site where the establishments must be buried. These technical difficulties increase the magnitude of the problems that could arise from over-reliance on the experience of the worker or a mere blueprint. Such problems include exposure to flood and collapse. This paper proposes a constructor-oriented visualization system via mobile gadgets in general construction sites with occluded structures. This proposal is consisted with three stages. First, "Stage of detecting manhole and extracting features" detects and extracts the basis point of occluded structures which is unoccluded manhole. Next, "Stage of tracking features" tracks down the extracted features in the previous stage. Lastly, "Stage of visualizing occluded constructions" analyzes and synthesizes the GPS data and 3D objects obtained from mobile gadgets in the previous stages. This proposal implemented ideal method through parallel analysis of manhole detection, feature extraction, and tracking techniques in indoor environment, and confirmed the possibility through occluded water-pipe augmentation in real environment. Also, it offers a practical constructor-oriented environment derived from the augmented 3D results of occluded water-pipings.

• Journal of the Korean Geographical Society
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• v.28 no.3
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• pp.227-246
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• 1993

Gender differences in the seperation of emplo-yment from home and commuting patterns of the Seoul Area are examined in this paper. Throughout the analysis, it is found that there exist a substantial gender variation in comm-uting rates. Even though the regional variation of commuting rates of male workers is very small, the female workers' regional variation of commuting rates is substantial. Especially, the area around the traditional central place of Kangbuk, the area near the Youngdungpo and Kuro where manufacturing and retailing activities are concentrated, and the area where low-income families are concentrated show high rate of female commuting. In contrast, the traditional residential area, especially the high-income area of Kangnam, shows lower rate of female commuting. Generally, female workers tend to work closer to home than male workers. Accordingly, the job search range of female workers is smaller than that of mle workers. But the areal unit of job search range of female workers is wider at least than Dong. The fact that female workers' job search area is smaller than male workers' implies that the job opportunity around the home location could have more impacts on female workers' job search process than male workers' job search process. There is a substantial difference in commuting behavior between male and female workers. In general, male workers commute longer, use more expensive transportation mode, and pay higher transportation cost in comparision with female workers. These gender differences in commuting behavior could be resulted not only form the gender difference in the seperation of employment form work, but also form the gender difference in the social status in both work place and home.

• Journal of Ecology and Environment
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• v.29 no.3
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• pp.265-275
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• 2006

This study represents the mechanism of progressive succession and potential natural vegetation on the forest vegetation in and surrounding Daegu. As a result of DCA, the feature of community was determined by an altitude and humid gradients. The soil moisture, contents of organic matter and total nitrogen increased as the community developed. In the interspecific association analysis, the forest vegetation was divided into two species groups and they were influenced by temperature and soil moisture. Especially, each two groups showed different stages of vegetation development according to the progressive succession and life form composition supported those results. It was predicted that Quercus variabilis, Q. acutissima, Q. dentata and Pinus densiflora communities would develop into Q. serrata community or Q. mongolica community depending on their location or species composition. In the study area, the potential natural vegetation was divided into 3 communities by biogeographical gradients such as species composition, soil environment, and geographical features: 1)Q. mongolica community in the middle-upper area of the mountain, 2)Q. serrata community in the middle-lower area of the mountain and 3)Carpinus cordata-Acer mono community in the cove area. It is suggested that the Q.mongolica and C.cordata-A.mono communities become actual vegetation and potential natural vegetation. But it is also suggested that the P. densiflora community would be changed into the potential natural vegetation of the Q. mongolica community and Q. serrata community on the basis of the present species composition.