• 한국지구물리탐사학회:학술대회논문집
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• 2000.09a
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• pp.54-69
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• 2000

There are groundwater trouble by high-salinity yield inducing sea-water intrusion in Cheju Island. It is used groundwater-GIS(Well-lnfo) in the maintenance and management of groundwater in Cheju Island to grasp groundwater trouble area and cause of high-salinity yield. For 16 wells certain to yield high-salinity, we logged specific electrical conductivity(EC) and tried to get hold of freshwater and saltwater relationship. As result of distribution of $Cl^-$ by depth, it is showed up groundwater trouble by high-salinity yield in the east coastal area and the partly north coastal area. The reason of high-salinity groundwater yield are low-groundwater level by the structure of geology and low-hydraulic gradient etc. There is necessity for management to development and use of groundwater in the high-salinity area, special management area.

• Journal of Wetlands Research
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• v.16 no.3
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• pp.431-440
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• 2014

To propose the improvement and management plans to strengthen the pollutant removal efficiency of dam reservoir's constructed wetlands(CWs), the operation status and configuration of CWs (including water depth, operational flow, water flow distribution, residence time, and pollutant removal efficiency, aspect ratio, open water/vegetation ratio etc.) were analyzed in 10 major wetlands constructed in dam reservoirs. The pollutant concentrations in the inflows of the studied CWs were lower than those of American and European constructed wetlands. Especially, organic matter concentrations in all of inflows were below 3 mg/L(as BOD) due to advanced treatment of sewage disposal plant and an intake of low concentration water during dry and normal seasons. The average removal efficiency of total nitrogen(TN) and total phosphorus(TP) for 10 CWs ranged from 7.6~67.6%(mean 24.9%) and -4.9~74.5%(mean 23.7%), respectively, showing high in wetlands treating municipal wastewater. On the other hand, the removal efficiency of BOD was generally low or negative with ranging from -133.3 to 41.7%. From the analysis of the operation status and configuration of CWs, it is suggested that the low removal efficiency of dam reservoir's CWs were caused by both structural (inappropriate aspect ratio, excessive open water area) and operational (neglecting water-level management, lack of facilities and operation for first flush treatment, lake of monitoring during rainy events) problems. Therefore, to enable to play a role as a reduction facility of non-point source(NPS) pollutants, an appropriate design and operation manuals for dam reservoir's CW is urgently needed. In addition, the monitoring during rainy events, when NPS runoff occur, must be included in operation manual of CW, and then the data obtained from the monitoring is considered in estimation of the pollutant removal efficiency by dam reservoir's CW.

• Restorative Dentistry and Endodontics
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• v.31 no.6
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• pp.452-459
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• 2006

Competition will usually develop between the opposing walls as the restorative resin shrinks during polymerization. Magnitude of this phenomenon may be depended upon cavity configuration and volume. The purpose of this sturdy was to evaluate the effect of cavity configuration and volume on microleakage of composite resin restoration that has margins on the enamel site only. The labial enamel of forty bovine teeth was ground using a model trimmer to expose a flat enamel surface. Four groups with cylindrical cavities were defined, according to volume and configuration factor(Depth x Diameter / C-factor) - Group I : 1.5 mm ${\times}$ 2.0 mm / 4.0, Group II : 1.5 mm ${\times}$ 6.0 mm / 2.0, Group III : 2.Omm ${\times}$ 1.72 mm / 5.62, Group IV : 2.0 mm ${\times}$ 5.23 mm / 2.54. After treating with fifth-generation one-bottle adhesive - BC Plus$^{TM}$ (Vericom, AnYang, Korea), cavities were bulk flted with microhybrid composite resin - Denfill$^{TM}$ (Vericom). Teeth were stored in distilled water for one day at room temperature and were finished and polished with Sof-Lex system. Specimens were thermocycled 500 times between 5$^{\circ}$C and 55$^{\circ}$C for 30 second at each temperature. Teeth were isolated with two layers of nail varnish except the restoration surface and 1 mm surrounding margins. Electrical conductivity (${\mu}$A) was recorded in distilled water by electrochemical method. Microleakage scores were compared and analyzed using two-way ANOVA at 95% level. The results were as follows: 1. Small cavity volume showed lower microleakage score than large one, however, there was no statistically significant difference. 2. There was no relationship between cavity configuration and microleakage. Factors of cavity configuration and volume did not affect on microleakage of resin restorations with enamel margins only.

• Restorative Dentistry and Endodontics
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• v.33 no.3
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• pp.177-183
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• 2008

It was reported that esthetic composite resin restoration reinforces the strength of remaining tooth structure with preserving the natural tooth structure. However, it is unknown how much the strength would be recovered. The purpose of this study was to compare the fracture resistance of three types of undermined cavity filled with composite resin with that of non-cavitated natural tooth. Forty sound upper molars were allocated randomly into four groups of 10 teeth. After flattening occlusal enamel, undermined cavities were prepared in thirty teeth to make three types of specimens with various thickness of occlusal structure (Group $1{\sim}3$). All the cavity have the 5 mm width mesiodistally and 7 mm depth bucco-lingually. Another natural 10 teeth (Group 4) were used as a control group. Teeth in group 1 have remaining occlusal structure about 1 mm thickness, which was composed of mainly enamel and small amount of dentin. In Group 2, remained thickness was about 1.5 mm, including 0.5 mm thickness dentin. In Group 3, thickness was about 2.0 mm, including 1 mm thickness dentin. Every effort was made to keep the remaining dentin thickness about 0.5 mm from the pulp space in cavitated groups. All the thickness was evaluated with radiographic Length Analyzer program. After acid etching with 37% phosphoric acid, one-bottle adhesive (Single $Bond^{TM}$, 3M/ESPE, USA) was applied following the manufacturer's recommendation and cavities were incrementally filled with hybrid composite resin (Filtek $Z-250^{TM}$, 3M/ESPE, USA). Teeth were stored in distilled water for one day at room temperature, after then, they were finished and polished with Sof-Lex system. All specimens were embedded in acrylic resin and static load was applied to the specimens with a 3 mm diameter stainless steel rod in an Universal testing machine and cross-head speed was 1 mm/min. Maximum load in case of fracture was recorded for each specimen. The data were statistically analyzed using one-way analysis of variance (ANOVA) and a Tukey test at the 95% confidence level. The results were as follows: 1. Fracture resistance of the undermined cavity filled with composite resin was about 75% of the natural tooth. 2. No significant difference in fracture loads of composite resin restoration was found among the three types of cavitated groups. Within the limits of this study, it can be concluded the fracture resistance of the undermined cavity filled with composite resin was lower than that of natural teeth, however remaining tooth structure may be supported and saved by the reinforcement with adhesive restoration, even if that portion consists of mainly enamel and a little dentin structure.

• The Journal of Fisheries Business Administration
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• v.16 no.1
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• pp.91-124
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• 1985

Mariculture is contrasted with inland aqua-culturing fisheries. It is defind as the Industry of rearing Aquaorganism in limited coastal area relatively shallow in depth. Then, It's coming into being realization of Mariculture in it is long in history that Mariculture was realized in Korea. But it is from the early part of 1960s, that this industry has normally developed. Owing to 200 miles economy-zone problems of coastal countries, the development of deep sea fishing was limited, so the Korean Government has now appreciated the importance of cultured industries in the field of coastal fisheries. And the Korean Mariculture the output of which was only 18, 000 M/T in '60s attained 540, 000M/T in 1980s, has now occupied its relative importance in Korean Fisheries Industry. So the purpose of this report is to suggest the prospect of technical development of mariculture in the future of Korea, through the analysis of the various problems that affect upon the individual management '||'&'||' fishing ground utilization, along with the appreciation of "how to extend of those technical innovation" and "how the fishermen's technique level is extended at this stage. According to this study, the result is summarized as follows. First, Maricultural technique is classified into 8 sub-techniques as follows, as shown in fig. 1.Fig. 1. The Formation structure of mariculture technique Second, the change of technical method of mariculture in coastal area of Korea has made as 5 stages; 1) Scattering of culturing organism 2) Culturing by putting stone and installing bamboo 3) Culturing by installing rope and seeding 4) Culturing of putting objectives in cages 5) Culturing fish by feed Third, the maricultural fisheries of Korea has about 70 years long in history. It began from 1910s. But at that time there was no special technique in aquaculture and its technique was confined in searching out the object of species. The species was laver, oyster ect.Forth, although realization of mariculture in Korea has been long time, it is of late from 1960s that this has been industrial with normal development, and its technique of mariculture has mainly has developed from 1970s. Its result not only contributed to the high growth in Korean ecconomy along with the well balanced development between industires, but also it played a great role for the resolution of nation's food problem. Especially maricultural production has shown its sustained annual increase of 13.8% during the last 20 years. So the portion of mariculture among total fisheries stucture was extended from 4.1% in the early 1960s to 22.4% in 1980s.Fifth, it could be safely said that such development in maricultural field is resulted from the activity of aquacultural institutes such as Fisheries Reseach '||'&'||' Development production of major kinds such as Oyster, Sea-mustard, and Laver etc. As well as in the innovation of aquaculturing method with synthetic fiber utilization. FRDA has played important role in the efficient propargation of new aquacultural technique.Sixth, as for the change in aquaculture structure and its during period between 1970s and 1980s, the private management participation shown 25% increase from household number of 45, 173 to 56, 268 in total number. And in the respect of the management scale, of their management decreased, while it showed an increase in relative large scale management, the increase over 3 employees compared with other fisheries field between '70s and 80s. This must be an major trait to be recorded, Now the data above mentioned are shown as in table 1 and 2.Table 1. The maricultural fishing ground development situation in 982.Table 2. The mariculture management as seen in the employmnet size in high seasion.Owing to the technical innovation, of the mariculture in coastal area new income of fishermen increased and it also is true that the number of fishermen participating in its industrialization increased. But the problem being from now on is the self-discharge of the destruction fishing ground considered resulted from rapid expansion in aquaculture industry and the preventive system of sentility of fishing ground. sentility of fishing ground.

• Journal of Gastric Cancer
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• v.5 no.1
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• pp.29-33
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• 2005

Purpose: To determine the prognostic values of the hematologic parameters checked preoperatively in gastric cancer patients, we evaluated and compared the relationship between hematologic parameters and clinicopathologic factors of gastric cancer patient. Materials and Methods: The medical records of 357 consecutive patients who had undergone surgery for gastric cancer at the Department of Surgery, Hanyang University Hospital, between Dec. 2,000 and Dec. 2003 were reviewed. To exclude any adverse effect of invasive procedures to hematologic parameters, the samples taken immediately at outpatient department was used. The normal range of serum albumin was defined above 3.5 g/dl, serum hemoglobin above 12 g/dl, and serum platelet count under $400\times10^{3}{\mu}l$. Patients were defined as group 1 when any of these parameters was abnormal, and defined as group 2 when all parameters were normal. The relationships between hematologic parameters and survival rate were investigated. Results: The mean values of platelet count increased, but level of serum albumin and serum hemoglobin decreased significantly according to the advancement of the disease stage (P=0.000). The differences of depth of tumor invasion and lymph node metastasis between the group 1 and the group2 was statistically significant (P=0.001). Three-year survival difference between group 1 and group 2 was significant (P=0.037). Conclusion: The hematologic parameters checked preoperatively in patients of gastric cancer are simple and cheap, meanwhile reflect the general condition of the patients. Any presence of anemia, hypoalbuminemia, or thrombocytosis can predict the progression of the disease and poor survival rates.

• Journal of dental hygiene science
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• v.17 no.2
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• pp.123-133
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• 2017

The aim of this study was to analyze in depth the standardized Clinical dental hygiene curriculum of the Fones School in the United States. We investigated the clinical dental hygiene curriculum in 2015~2016 including title, credit, hours, contents, goals, competencies, and evaluation. We obtained the course syllabus and data related to each subject, for each grade, from the professors and students at the university. The goals and competencies, of the clinical dental hygiene program, which were based on the goals of the Fones School and the mission of the University of Bridgeport, were developed in accordance with the dental hygienist practice standards proposed by the American Dental Hygienists Association. The curriculum consisted of theory to teach proper dental hygiene care procedures and incorporated practical exercises that modeled an actual clinical setting. The students had to document the procedures performed for each client/patient and improve their clinical competency through discussion with the professors. Dental hygiene care should be provided for children, adolescents, adults, elderly, and patients, which includes patients with moderate or severe periodontal status. Students were evaluated by a paper test or case study presentation and their clinical evaluation was based on their clinical competency. In particular, professors evaluated students on a rotational basis, so they could evaluate the level of achievement of clinical competency of all students and find ways to improve any weaknesses. Therefore, the current study suggested that clinical dental hygiene program in Korea could be improved if based on the curriculum of Fones School in the United States.

• Progress in Medical Physics
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• v.24 no.4
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• pp.315-322
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• 2013

The aim of this work is to verify the self-quality assurances in medical institutions in Korea through the external audits by the group of experts and have a mutual discussion of the systematic problems. In order to validate the external audits 30 of 80 medical institutions across the nation were picked out considering the regional distribution and the final 25 institutions applied voluntarily to take part in this work. The basic rules were setup that any information of the participants be kept secrete and the measurements be performed with the dosimetry system already verified through intercomparision. The outputs for 2 or more photon beams, the accuracy of gantry rotation and collimator rotation and the poistional accuracy of MLC movement were measured. The findings for the output measurement showed the differences of -0.8%~4.5%, -0.79%~3.01%, and -0.7%~0.07% with respect to that of the verified dosimetry system for the 6MV, 10MV, and 15MV, respectively. For the reference absorbed dose 8 (16%) of 50 photon beams in 25 medical institutions differed 2.0% or greater from the reference value. The coincidences of Field size with x-ray beam and radiation isocenters of Gantry roration and collimator rotation gave the results of within ${\pm}2$ mm for every institute except 2 institutions. The positional accuracy of MLC movement agreed to within ${\pm}1$ mm for every institute. For the beam qualities of 6 MV photon beams kQ values showed the distribution within 0.4% between maximum and minimum. For the protocols 21 institutions (84%) used absorbed dose to water based protocol while 4 insitutions (16%) used air kerma based one. 22 institutions employed the SSD technique while 3 institutions did the SAD one. External audit plays an important role in discovering the systematic problems of self-performing Quality Assurances and having in depth discussion for mutual complementation. Training experts of international level as well as national support system are required so that both the group of experts of medical physicists and government laboratory could perform together periodical and constant external audits.

• Geophysics and Geophysical Exploration
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• v.13 no.4
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• pp.357-363
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• 2010

In this study, we investigated the geologic structure of the basement and overlying sediments of the construction site of the dinosaur egg fossil museum in Hwasung, Gyeonggi Province through refraction seismology, drilling, and downward seismic velocity measurements in the drill holes. The construction site ($350{\times}750\;m^2$) is located in the reclaimed area south of Sihwa Lake, Gojeong-ri. About 6,950 m of seismic refraction data consisting of 11 lines were acquired using a sledge hammer source. Drilling to the basement was performed at five sites. Sediment samples from drilling were analysed for grain-size distribution and age dating. At two drill holes, seismic velocity was measured with depth using a hammer as a seismic source. The geological structure of the study area consists of, from top to bottom, a tidal flat layer (5 ~ 12 m thick), a weathered soil layer (2 ~ 8 m thick), and the basement. The basement is interpreted as Cretaceous sedimentary rocks that tend to be shallow eastward. The volume of the tidal flat sediments and weathered soil in the study area is estimated as $1.4{\times}10^6\;m^3$, weighing $3.5{\times}10^6$ tons. The rate of sea level rise since 8,000 yrs BP is estimated to be 0.1 ~ 0.15 cm/yr.

• Journal of Korea Port Economic Association
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• v.33 no.2
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• pp.53-82
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• 2017

The purpose of this study is to show the clustering trend and compare empirical results, as well as to choose the clustering ports for 3 Korean ports (Busan, Incheon, and Gwangyang) by using meta-frontier DEA (Data Envelopment Analysis) and integer models on 38 Asian container ports over the period 2005-2014. The models consider 4 input variables (birth length, depth, total area, and number of cranes) and 1 output variable (container TEU). The main empirical results of the study are as follows. First, the meta-frontier DEA for Chinese seaports identifies as most efficient ports (in decreasing order) Shanghai, Hongkong, Ningbo, Qingdao, and Guangzhou, while efficient Korean seaports are Busan, Incheon, and Gwangyang. Second, the clustering results of the integer model show that the Busan port should cluster with Dubai, Hongkong, Shanghai, Guangzhou, Ningbo, Qingdao, Singapore, and Kaosiung, while Incheon and Gwangyang should cluster with Shahid Rajaee, Haifa, Khor Fakkan, Tanjung Perak, Osaka, Keelong, and Bangkok ports. Third, clustering through the integer model sharply increases the group efficiency of Incheon (401.84%) and Gwangyang (354.25%), but not that of the Busan port. Fourth, the efficiency ranking comparison between the two models before and after the clustering using the Wilcoxon signed-rank test is matched with the average level of group efficiency (57.88 %) and the technology gap ratio (80.93%). The policy implication of this study is that Korean port policy planners should employ meta-frontier DEA, as well as integer models when clustering is needed among Asian container ports for enhancing the efficiency. In addition Korean seaport managers and port authorities should introduce port development and management plans accounting for the reference and clustered seaports after careful analysis.