• International Journal of Highway Engineering
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• v.11 no.1
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• pp.177-186
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• 2009

Rumble strip was introduced in highway pavement for driver's safety in Korea on 2000. With proving its effectiveness, total length of highway with rumble strip has increased. This research team suggested a modified form of the existing rumble strip, which was placed on new concrete pavement during construction. The modified construction equipment was applied on test section at PyungTeak-Eumsung highway with some performance experiments. Through the equation of stopping sight distance proposed AASHTO, the modified form is safer than the existing one due to 0.65m of extra width. The indoor noise test showed that the modified form $3.5{\sim}9dB(A)$ noisier than the main pavement, which wasn't applied by rumble method. Therefore, it was one of alternatives to prevent sleeping. The modified form made the frequency effected on man's eye. There were no differences of the noise and vibration between modified form and existing one. However, that driver who participated on operating test on that section felt that the former was safer than the latter. It can be concluded that modified form can be applied to the new concrete pavement, that will decrease traffic accident.

• Korean Journal of Medicinal Crop Science
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• v.5 no.3
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• pp.177-185
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• 1997

Twenty-four major ecological and physiolosical characters of the 54 accessions of taro(Colocasia antiquorum) were observed in the growing seasons of 1995 and 1996 in $Ch{\breve{o}}nju$, Korea. The average days to emergence of the 54 accessions were 21.7 and the accession which had the shortest days to emergence was Kurye #2. Petiole color of most accessions was green, except $Ich{\breve{o}}n$ #1, Iri #1, Puan #1 and Taiwan #1 which had purple petioles. All the accessions had cormels except Taiwan #1 which had long runners without cormels. Average yield of the accessions was 3,719 kg/10a and total carmel weight, average carmel number, average carmel and average corm weight were 787g/plant, 39.2/plant, 20.3g/cormel, and 263.6g/plant, respectively. Accessions $Ch{\breve{o}}ngju$ #1 and Wanju #1 showed superiority in the three important characters, total carmel weight/plant, average carmel weight, and corm weight. Multivariate analysis for the 24 characters indicated that petiole color and carmel type had relatively higher coefficient of variation, 56.8 and 44.4 %, respectively. Fifty four taro accessions could be classified into 11 groups with D(${\sqrt{D^{2}}$) value of 110 on the basis of phenotypical characteristics. Most accessions were inclued in Group II. The Group I in which Taiwan #1 was included was genetically the most distant from the other groups. Accessions with purple petioles were grouped into the three different subgroups in which green petiole accessions were not included, indicating high dissimilarity between the different petiole color accessions. All the accessions grouped into the Group VIII, $Ch{\breve{o}}ngju$ #1, Wanju #1, Wanju #3, and $Taech{\breve{o}}n$ #2, had higher bioogical yield. Some accessions collected from the same district showed a high dissimilarity by being classified into the different subgroups.

• Radiation Oncology Journal
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• v.26 no.1
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• pp.56-64
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• 2008

Purpose: Cathepsin D(CD) is a lysosomal acid proteinase that is related to malignant progression, invasion, and a poor prognosis in several tumors. The aim of this study was to evaluate the prognostic clinical significance of CD and p53 expression in pretreatment biopsy specimens from patients with locally advanced rectal cancer who were treated with preoperative chemoradiation. Materials and Methods: Eighty-nine patients with locally advanced rectal cancer(cT3/T4 or N+) were included in this study. Preoperative chemoradiation consisted of a dose of 50.4 Gy of pelvic radiation and two concurrent cycles of administration of 5-fluorouracil and leucovorin. Surgery was performed six weeks after chemoradiation. CD and p53 expression in pretreatment formalin-fixed paraffin-embedded tumor biopsy specimens were assessed by immunohistochemical staining using a CD and p53 monoclonal antibodies. The threshold value for a positive stain in tumor tissue and stromal cells was 1+ intensity in 10% of the tumors or stromal cells, respectively. Results: Positive CD expression was found in 57(64%) of the tumors and 32(35%) of the stromal cell specimens. There was no association with CD expression of the tumor or stromal cells and patient characteristics. There was a correlation between tumor CD expression with stromal cell CD expression(p=0.01). Overexpression of p53 was not a significant prognostic factor. The 5-year overall survival(OS) and disease-free survival(DFS) rates were not different between tumor CD-negative and positive patient biopsy samples(69% vs. 65%, 60% vs. 61%, respectively). The 5-year OS rates in the tumor-negative/stromal cell-negative, tumor-negative/stromal cell-positive, tumor-positive/stromal cell-negative and tumor-positive/stromal cell-positive biopsy samples were 75%, 28%, 62%, and 73%, respectively. Stromal cell staining only without positive tumor staining demonstrated the worst overall survival prognosis for patients(p=0.013). Conclusion: Overexpression of p53 in rectal biopy tissue was not associated with prognostic significance. In the pretreatment biopsy specimens, an exclusive increase in CD expression in stromal cells without tumor expression was related to poor overall survival in patients with locally advanced rectal cancer treated with preoperative chemoradiation.

• Journal of Korean Society of Forest Science
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• v.107 no.4
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• pp.351-360
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• 2018

This study was conducted to analyze the responses of chlorophyll contents and growth of Pinus densiflora and Quercus variabilis seedlings on distance from the well and $CO_2$ flux after the artificial $CO_2$ release. From June 1 to 30, 2016, $CO_2$ gas was injected at the rate of $6L\;min^{-1}$ at the study site in Eumseong. Chlorophyll content was analyzed in the middle of July, 2016, and root collar diameter (RCD), height (H), and biomass were measured in May and December, 2016 after planting 2-year-old P. densiflora and 1-year-old Q. variabilis seedlings in May, 2015. The chlorophyll content of P. densiflora seedlings did not show a significant correlation with $CO_2$ flux, whereas the chlorophyll content of Q. variabilis seedlings showed a significant negative correlation with increasing $CO_2$ flux (P<0.05). The RCD and H growth rates of both species showed the significant difference in the distance from the well of the $CO_2$ anthropogenic release treatment. In particular, the RCD and H growth rate of P. densiflora seedlings and the RCD growth rate of Q. variabilis seedlings increased significantly as the seedlings were closer to the well, but the H growth rate of Q. variabilis seedlings decreased significantly. In addition, as the $CO_2$ concentration in the ground increases, ${\Delta}R/S$ ratio increases in both species, suggesting that the high $CO_2$ concentration in the soil promotes carbon distribution relative to the root part. The results of this study can be used as data necessary to monitor the $CO_2$ leakage and physiological and growth responses of both species to leakage of stored $CO_2$ in the future.

• Journal of Intelligence and Information Systems
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• v.26 no.4
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• pp.87-109
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• 2020

Currently, thanks to the major stride made in developing wired and wireless communication technology, a variety of IT services are available on land. This trend is leading to an increasing demand for IT services to vessels on the water as well. And it is expected that the request for various IT services such as two-way digital data transmission, Web, APP, etc. is on the rise to the extent that they are available on land. However, while a high-speed information communication network is easily accessible on land because it is based upon a fixed infrastructure like an AP and a base station, it is not the case on the water. As a result, a radio communication network-based voice communication service is usually used at sea. To solve this problem, an additional frequency for digital data exchange was allocated, and a ship ad-hoc network (SANET) was proposed that can be utilized by using this frequency. Instead of satellite communication that costs a lot in installation and usage, SANET was developed to provide various IT services to ships based on IP in the sea. Connectivity between land base stations and ships is important in the SANET. To have this connection, a ship must be a member of the network with its IP address assigned. This paper proposes a SANET-CC protocol that allows ships to be assigned their own IP address. SANET-CC propagates several non-overlapping IP addresses through the entire network from land base stations to ships in the form of the tree. Ships allocate their own IP addresses through the exchange of simple requests and response messages with land base stations or M-ships that can allocate IP addresses. Therefore, SANET-CC can eliminate the IP collision prevention (Duplicate Address Detection) process and the process of network separation or integration caused by the movement of the ship. Various simulations were performed to verify the applicability of this protocol to SANET. The outcome of such simulations shows us the following. First, using SANET-CC, about 91% of the ships in the network were able to receive IP addresses under any circumstances. It is 6% higher than the existing studies. And it suggests that if variables are adjusted to each port's environment, it may show further improved results. Second, this work shows us that it takes all vessels an average of 10 seconds to receive IP addresses regardless of conditions. It represents a 50% decrease in time compared to the average of 20 seconds in the previous study. Also Besides, taking it into account that when existing studies were on 50 to 200 vessels, this study on 100 to 400 vessels, the efficiency can be much higher. Third, existing studies have not been able to derive optimal values according to variables. This is because it does not have a consistent pattern depending on the variable. This means that optimal variables values cannot be set for each port under diverse environments. This paper, however, shows us that the result values from the variables exhibit a consistent pattern. This is significant in that it can be applied to each port by adjusting the variable values. It was also confirmed that regardless of the number of ships, the IP allocation ratio was the most efficient at about 96 percent if the waiting time after the IP request was 75ms, and that the tree structure could maintain a stable network configuration when the number of IPs was over 30000. Fourth, this study can be used to design a network for supporting intelligent maritime control systems and services offshore, instead of satellite communication. And if LTE-M is set up, it is possible to use it for various intelligent services.