• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1178-1183
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• 2008

This paper is about a study of atomizing characteristics of a Multi-Nozzle, which is an important part in a flooding water mist system for extinguishing fires broke out in ships. Comparing the results of experiments for the Single-Nozzle to that of numerical analyses, characteristics of a Multi-Nozzle can be found out. In situation of a Single-Nozzle’s, the atomizing angle was $34^{\circ}$. And in situation of Multi-Nozzle that combined with 5 single-nozzles, the atomizing angle increase to $125^{\circ}$. The effective area is 3.7 times of the former. The quality factor will reduce, if the diameter of the atomizing region of the nozzle reduces. Although the atomizing angle is reduced because of the atomizing property, the value of SMD still shows a good result.

• Journal of the Korean Geotechnical Society
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• v.18 no.5
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• pp.209-220
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• 2002

Because the allowable current loading of buried electrical transmission cables is frequently limited by the maximum permissible temperature of the cable or of the surrounding ground, there is a need for cable backfill materials that can maintain a low thermal resistivity (less than 5$0^{\circ}C$-cm/watt) even while they are subjected to high temperatures for prolonged periods. Temperatures greater than 5$0^{\circ}C$ to 6$0^{\circ}C$ may lead to breakdown of cable insulation and thermal nlnaway if the surrounding backfill material is unable to dissipate the heat as rapidly as it is generated. This paper describes the results of studies aiming at the development of backfill material to reduce the thermal resistivity. A large number of different additive materials were tested to determine their applicability as a substitute material. Tests were called out for DonUing river sand, a relatively uniffrm sand of very high thermal resistivity (5$0^{\circ}C$ -cnuwatt at 10% water content, 26$0^{\circ}C$-cm/watt when dry), and Jinsan granite screenings, and A-2(sand and gravel mixture), E-1 (rubble and granite screenings mixture), a well-graded materials with low thermal resistivity (about 35$^{\circ}C$ -cm/watt when at 10 percent water content, 10$0^{\circ}C$-cm/watt when dry). Based on this research, 3 types of backfill materials were suggested for improved materials with low thermal resistivity.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.5
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• pp.967-979
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• 2013

Now a day, Wireless Sensor Networks (WSNs) are being widely used in different areas one of which is healthcare services. A wireless medical sensor network senses patient's vital physiological signs through medical sensor-nodes deployed on patient's body area; and transmits these signals to devices of registered medical professionals. These sensor-nodes have low computational power and limited storage capacity. Moreover, the wireless nature of technology attracts malicious minds. Thus, proper user authentication is a prime concern before granting access to patient's sensitive and private data. Recently, P. Kumar et al. claimed to propose a strong authentication protocol for healthcare using Wireless Medical Sensor Networks (WMSN). However, we find that P. Kumar et al.'s scheme is flawed with a number of security pitfalls. Information stored inside smart card, if extracted, is enough to deceive a valid user. Adversary can not only access patient's physiological data on behalf of a valid user without knowing actual password, can also send fake/irrelevant information about patient by playing role of medical sensor-node. Besides, adversary can guess a user's password and is able to compute the session key shared between user and medical sensor-nodes. Thus, the scheme looses message confidentiality. Additionally, the scheme fails to resist insider attack and lacks user anonymity.

• The Journal of the Korea Contents Association
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• v.18 no.5
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• pp.464-471
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• 2018

The business card is regarded as the simplest means as well as a tool the most likely to use as a means of sales. Every day, we are exchanging business cards with many customers, but the paper based business card is easy to discard and difficult for searching information on the business card. As a solution, if we take a photographed business card with a smart phone and make it into a database, we can easily obtain customer information we wanted for sales at any time. In this study, we develop an application solution based on electronic business card database that supports sales management. The system operates in a cloud environment and has various decision support functions such as customer's human network management, customer classification, and finding prospective customers.

• Textile Coloration and Finishing
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• v.17 no.5 s.84
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• pp.53-60
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• 2005

Fusing press m/c is used for heating and pressing the specimens that are fed into between the two moving belts. Therefore the belt movement, belt temperature, and the pressure between belts must be kept constant. Especially, the belts should move in a limited operation range. When the belts run far out of the operation point, the machine has to be stopped, which results in a product defect because the fusing conditions, e.g., temperature and pressure, change during the transient process time period. It is important to avoid the belt stopping by maintaining the belt movement in a limited range. This study reports about the movement of the endless fusing belt in a long-span roller fusing m/c. The belt position changes as the 1st-order system does; if the roller axes are slanting each other with a certain angle, the belt running around the two rolls shows a dynamic behavior with the time that deviates fastly at the beginning from the initial condion and slows down. Then it reaches at a final position. The skewer the axes, the greater the position change. The inital change rate of the belt becomes large as the skewness of the axes between the two rollers increases.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.3
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• pp.522-538
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• 2013

Content based image retrieval has become an increasingly important research topic for its wide application. It is highly challenging when facing to large-scale database with large variance. The retrieval systems rely on a key component, the predefined or learned similarity measures over images. We note that, the similarity measures can be potential improved if the data distribution information is exploited using a more sophisticated way. In this paper, we propose a similarity measure learning approach for image retrieval. The similarity measure, so called Fisher kernel, is derived from the probabilistic distribution of images and is the function over observed data, hidden variable and model parameters, where the hidden variables encode high level information which are powerful in discrimination and are failed to be exploited in previous methods. We further propose a discriminative learning method for the similarity measure, i.e., encouraging the learned similarity to take a large value for a pair of images with the same label and to take a small value for a pair of images with distinct labels. The learned similarity measure, fully exploiting the data distribution, is well adapted to dataset and would improve the retrieval system. We evaluate the proposed method on Corel-1000, Corel5k, Caltech101 and MIRFlickr 25,000 databases. The results show the competitive performance of the proposed method.

• Journal of the Korean Vacuum Society
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• v.16 no.3
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• pp.181-186
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• 2007

We have investigated and analyzed the effects of the evaporation rate of MgO films on the MgO properties and the discharge characteristics of a plasma display panel(PDP). The MgO properties such as the crystal orientation, the surface roughness, the film structure, and cathode-luminescence (CL) spectra were inspected using XRD (X-ray diffraction), AFM(atomic force microscopy). And the discharging characteristics of the PDP such as the firing voltage, discharging current, and luminescence were measured using a vacuum chamber with oscilloscope (TDS 540C), current probe (TCP-312A), color meter (CS-100A) and etc. From the experiments results we confirmed the optimum evaporation rate at $5{\AA}/sec$, the MgO properties were shown to be strongly dependent on the evaporation rate, and the MgO properties had an effecton the optical and electrical characteristics. In other words, if the evaporation rates increase than $5{\AA}/sec$, the intensity of (200) orientation and cathode-luminescence (CL) spectra reduce, and the firing vlotage was increased. So the luminuous efficiency grows worse.

• Clinical and Experimental Reproductive Medicine
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• v.25 no.2
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• pp.217-231
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• 1998

The effectiveness of intrauterine insemination (IUI) combined with controlled ovanan hyperstimulation (COH) in the treatment of infertility with various etiologies was compared in a total of 152 cycles. Patients received a maximum of three IUI cycles for the treatment. Severe male ($<2\times10^6$ motile sperm) or age factor (> 39 y) patients were excluded in this study. Pregnancy was classified as clinical if a gestational sac was seen on ultrasound. The overall clinical pregnancy rate was 7.9% per cycle (12/152) and 9.7% per patient (12/124). The pregnancy rates were 0% in unstimulated natural (0/18), 7.5% in CC (3/40), 8.2% in CC+hMG (4/49), 5.9% in GnRH-a ultrashort (1/17), 5.9% in GnRH-a long (1/17) and 27.3% in dual suppression cycles (3/11), respectively. The pregnancy rate was higher in dual suppression cycle than other stimulated cycles, but this was not significant. The multiple pregnancy rates were 25.0% (2 twins and 1 triplet). No patient developed ovarian hyperstimulation. Abortion rates were 66.7% in CC (2/3) and 100% in ultrashort cycles (1/1). The livebirth rate was 5.9% per cycle (9/152) and 7.3% per patient (9/124). There were no differences in age, duration of infertility, follicle size, total ampules of gonadotropins and days of stimulation between pregnant and non-pregnant groups. However, significant(P<0.05) differences were observed in the level of estradiol $(E_2)$ on the day of hCG injection ($3,266.6{\pm}214.2$ vs $2,202.7{\pm}139.4$ pg/ml) and total motile sperm count ($212.1{\pm}63.4$ vs $105.1{\pm}9.9\times10^6$) between pregnant group and non-pregnant group. These results suggest that IUI combined with successful ovarian stimulation tends to improve the chance of pregnancy as compared to IUI without COH and a total motile sperm count may be considered predictive of the success for pregnancy.

• Animal cells and systems
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• v.5 no.3
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• pp.163-177
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• 2001

Most, if not all, aphids harbor intracellular bacterial symbionts, called Buchnera, in their bacteriocytes, huge cells differentiated for this purpose. The association between Buchnera and aphids is so intimate, mutualistic and obligate that neither of them can any longer reproduce independently. Buchnera are vertically transmitted through generations of the host insects. Evidence suggests that Buchnera were acquired by a common ancestor of aphids 160-280 million years ago, and have been diversified, since then, in parallel with their aphid hosts. Molecular phylogenetic analyses indicate that Buchnera belong to the g subdivision of the Proteobacteria. Although Buchnera are close relatives of Escherichia coli, they contain move than 100 genomic copies per cell, and their genome size is only one seventh that of E. coli. The complete genome sequence of Buchnera revealed that their gene repertoire is quite different from those of parasitic bacteria such as Mycoplasma, Rickettsia and Chlamydia, though their genome sizes have been reduced to a similar extent. Whereas these parasitic bacteria have lost most genes for the biosynthesis of amino acids, Buchnera retain many of them. In particular, Buchnera's gene repertoire is characteristic in the richness of the genes for the biosynthesis of essential amino acids that the eukaryotic hosts are not able to synthesize, reflecting a nutritional role played by these symbionts. Buchnera, when housed in the bacteriocyte, selectively synthesize a large amount of symbionin, which is a homolog of GroEL, the major stress protein of E. coli. Symbionin not only functions as molecular chaperone, like GroEL, but also has evolutionarily acquired the phosphotransferase activity through amino acid substitutions. Aphids usually profit from Buchnera's fuction as a nutritional supplier and, when faced with an emergency, consume the biomass of Buchnera cells as nutrient reserves.

• Korean Journal of Bronchoesophagology
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• v.9 no.2
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• pp.36-43
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• 2003

Background and objectives; Esophageal cancer is one of the most malignant tumors and has a poor prognosis. Many clinical studies have been tried for improving prognosis of esophageal cancer. Some clinical studies used molecular markers as the predictor of prognosis & the indicator for the choice of multimodality treatments. We investigated the relationship between some molecular markers, including p53 mutation, expression of bc12, Ki67 index, expression of E-Cadherin and the prognosis of esophageal cancer, Materials and Method; The materials used in this study were the tumor specimens from 72 esophageal cancer patients who underwent esophagectomy from 1987 to 2002 in our institute. The mutation of p53, expression of bc12, Ki67 index, and expression of E-cadherin were examined by using the tissue array and immunohistochemical staining method. The patients were subgrouped into higher Ki67 index group if the index was higher than 30. The patients were also subgrouped into grade 1(>90%), grade 2(50∼90%), grade 3 (10∼50%), and grade 4(<10%) according to the rate of E-Cadherin expression. We studied the relationship between the rates of immunohistochemical staining and the survival rate. Results: Seventy two tumor specimens from 72 patients were studied. (mean age ; 59.6 years, male female = 69 : 3) The histologic type of the specimens was all squamous cell carcinoma. The patient's number of stage IIA, IIB, and Ⅳ was 30, 37, and 7 respectively, Thirty patients were alive and overall 5 year-survival rate was 28%. The mutation of p53 was shown in 54.2% of the patients. Five year survival rates of negative and positive groups were 29% and 28% respectively.(p=0.4) Expression of bc12 gene was found in 13.9% of the specimens. Five year survival rates of negative and positive groups were 30% and 21%.(p=0.3) Higher Ki67 index was correlated to poorer differentiation.(p=0.05) Five year survival rates of higher and lower groups of Ki67 index were 47% and 30%.(p=0.15) Higher expression rate of E-Cadherin showed better differentiation.(p=0.04). However we couldn't find any survival differences between these 4 groups.(p=0.23) Conclusion; We could not find any molecular markers meaningful in the prognosis of esophageal cancer patients. We just found the tumor markers correlated to the differentiation of esophageal cancer. However, we knew that we need further study with some more samples to stratify other important prognostic factors of esophageal cancer.