• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.4B
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• pp.191-199
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• 2007

Mobile node has to register its current location to Home Agent when it moves to another network while away from home. However, the registration procedure cannot be completed successfully when Home Agent is protected by the VPN gateway which guards MN's home network and discards the unauthorized packets incoming from outside as a lack of security association(SA) between the Care-of address and security policy of the home network so that the binding registration message without SA is discarded smoothly by the VPN gateway. This paper presents the authentication and key exchange scheme using the AAA infrastructure for a user in Internet to access the home network behind the VPN gateway. By defining the role of authentication and tunnel processing for each agent or relay entity, this paper presents the procedure to register the current location to its Home Agent with secure manner. Performance result shows cost improvement up to 40% comparing with existing scheme in terms of the packet loss cost, the property of mobility and traffic.

• Archives of Plastic Surgery
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• v.34 no.4
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• pp.490-492
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• 2007

Purpose: Nipple reconstruction is an important step in breast reconstruction after mastectomy. There are considerable number of reconstructive methods developed over the past years. Each of these has not only its own special advantages, but also limitations. Therefore, no single method has become the overwhelming favorite. Sometimes it seems to be compromised when the nipple must be located directly over a linear scar. Methods: A 48-year-old female patient received a central lumpectomy with circumareolar resection of the nipple areolar complex 4 months ago. The newly designed nipple must be positioned directly astride a scar. We drew two equal-sized rectangular flaps sharing a common limb on a transverse scar and the result was two opposing plow form. Each flap size was about 1.3 cm wide and 2.5 cm long. First we elevated the flap from the distal part at a deep dermal plane, then deepened the level of dissection to raise the dermal-fat flaps. The donor site could be closed directly without any dog-ear deformity. Then we folded down the elevated flaps and loosely sutured skin with nonabsorbable materials. Each flap inner side was approximated side by side. Finally we made new natural nipple with 6 mm projection. We applied tattooing in the areola area with micropigmentation device after three months. Results: After ten months of follow-up periods, the nipple projection was stable and symmetric. The nipple projection was 3.1 mm, compared with 2.8 mm for the opposite nipple. Conclusion: Our experiences shows that this double opposing plow flap is a particularly useful and simple technique when there is a traverse scar crossing the center of the proposed nipple area.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.12 no.3
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• pp.39-47
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• 2002

This paper deals with study of a new framework for the traceback of distributed DoS(Denial of Service) attacks in the Internet, in which many sources flood "spoofed" IP packets towards a single victim. In our scheme, the destination host traces those anonymous packets' losses, and infers the logical end-to-end paths back towards the sources. This method is based on the fact that there is a strong correlation between packet losses when those packets traverse along a same route, and the simulation results show high probabilities of detecting the topology under a certain condition. Compared with previous approaches, our scheme has a number of distinct features: It can be performed in realtime or non-realtime, without any supports of routers or ISPs. Our results may be applied to the inference of physical topology and to support previous approaches.pproaches.

• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.1066-1080
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• 2024

SMART100 has a containment pressure and radioactivity suppression system (CPRSS) for passive containment cooling system (PCCS). This prevents overheating and over-pressurization of a containment through direct contact condensation in an in-containment refueling water storage tank (IRWST) and wall condensation in a CPRSS heat exchanger (CHX) in an emergency cool-down tank (ECT). The Korea Atomic Energy Research Institute (KAERI) constructed scaled-down test facilities, SISTA1 and SISTA2, for the thermal-hydraulic validation of the SMART100 CPRSS. Three separate effect tests were performed using SISTA1 to confirm the heat removal characteristics of SMART100 CPRSS. When the low mass flux steam with or without non-condensable gas is released into an IRWST, the conditions for mitigation of the chugging phenomenon were identified, and the physical variables were quantified by the 3D reconstruction method. The local behavior of the non-condensable gas was measured after condensation inside heat exchanger using a traverse system. Stratification of non-condensable gas occurred in large tank of the natural circulation loop. SISTA2 was used to simulate a small break loss-of-coolant accident (SBLCOA) transient. Since the test apparatus was a metal tank, compensations of initial heat transfer to the material and effect of heat loss during long-term operation were important for simulating cooling performance of SMART100 CPRSS. The pressure of SMART100 CPRSS was maintained below the design limit for 3 days even under sufficiently conservative conditions of an SBLOCA transient.

• Journal of the Korea Concrete Institute
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• v.16 no.6 s.84
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• pp.741-750
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• 2004

Air voids in hardened concrete have an important influence on concrete durability such as freeze-thaw resistance, surface scaling resistance, and water permeability, and they have been characterized by spacing factor Linear traverse and point count methods in ASTM standard have been used in estimating an air void system in hardened concrete. However, these methods require lots of time and efforts, further they are not repeatable. Image analysis method could be utilized In estimating an air void systems in hardened concrete with a developments of microscope, digital camera and computer program. The purpose of this study was to develope image analysis method and provide a guideline by comparing the results from ASTM method and image analysis method. The concerns were at air void content and diameter distribution, air voids system as well as spacing factors. The experimental variables included air content by air entrained agent (0, 0.01, $0.03\%$) and depth of specimen (top, middle, bottom). The result showed that it was possible to calculate spacing factor using image analysis technique, as well as air content, air diameter distribution, and air structure. This study also contributed in developing an reasonable and repeatable image analysis method.

• Journal of KIISE:Databases
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• v.34 no.5
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• pp.420-436
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• 2007

The choice of an effective indexing method is crucial to guarantee the performance of the spatial join operator which is heavily used in geographical information systems. The $R^*$-tree based method is renowned as one of the most representative indexing methods. In this paper, we propose an efficient spatial join technique based on the DOT(Double Transformation) index, and compare it with the spatial Join technique based on the $R^*$-tree index. The DOT index transforms the MBR of an spatial object into a single numeric value using a space filling curve, and builds the $B^+$-tree from a set of numeric values transformed as such. The DOT index is possible to be employed as a primary index for spatial objects. The proposed spatial join technique exploits the regularities in the moving patterns of space filling curves to divide a query region into a set of maximal sub-regions within which space filling curves traverse without interruption. Such division reduces the number of spatial transformations required to perform the spatial join and thus improves the performance of join processing. The experiments with the data sets of various distributions and sizes revealed that the proposed join technique is up to three times faster than the spatial join method based on the $R^*$-tree index.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.4
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• pp.413-422
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• 2012

After development of GPS in the 1960's, the United States released SA(Selective Availability) in 2000 and then the GPS has become commercialized to the present. The result of repeatedly developed GPS observation, the GPS real-time observation methods is RTK which basically always needs two base stations and has a fault of the accuracy decreasing as the distance between a mobile station and a receiver is increasing. Because of these weakness, VRS method has come out. VRS(Virtual Reference Station) generates the imaginary point near mobile station from several observatory datum of GPS, sets the accurate location of mobile station, thus shows high reliability and mobility. Now, the cadastral datum point is used with azimuth, repetition, and graphical traversing method for traverse network. The result of measurement indicates many problems because of different accomplishment interval given point, restrictions on the length of the conductor, many errors on the observations. So, this study did comparative analysis of the cadastral datum points through VRS method by Continuously Operating Reference Station. Through the above comparative analysis, The comparative result between surveyed result with repetition method through total station observed Cadastral Control Points and surveyed result with VRS-RTK has shown that average error of x-axis is -0.08m, average error of y-axis, +0.07m and average distance error is +0.11m.

• The Journal of the Korea Contents Association
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• v.9 no.11
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• pp.254-261
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• 2009

This study suggested that the table of CT-simulator and the laser alignment system using diagnostic CT scanner have an efficient method for improvement in alignment between the planned target center of traverse image with CT scanner. It was conducted on the daily QA when presented in the AAPM TG66 with correcting the laser alignment system using geometric trigonometric functions and investigated the effectiveness of correction methods as compared with those before and after correction. Before correction error was 3.82mm between the planned target center of image, the table longitudinal axis was twisted with 0.436o. The laser alignment system using geometric trigonometric functions in after correction was satisfied with tolerance limits of ${\pm}2mm$ when occurred about 0.7mm in errors between the planned target center. The table correction to satisfy the geometric accuracy is very inefficient over against the time and economic loss as well as technical limits in the case of application as only radiation therapy associated with CT-simulator with diagnostic CT scanner in use. But, the method which corrects the laser alignment system is economic and relatively simple with possibility of getting well geometric accuracy and we suppose that it is efficient method for applying in the clinic.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.627-631
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• 2010

A new cultivar of lettuce (Lactuca sativa L.) with wrinkled traverse elliptic and deep red leaf, 'Chunpungjeokchukmyeon' which has late bolting and deep red expression leaf color was developed from a cross between 'Pojabijeokchukmyeon' (red leaf color and late bolting) and 'Meokchima' (Deep red and low yield). The cross and selection for advanced lines had been done by the pedigree method during 2000-2007. The advanced lines were evaluated for yield and adaptability at several locations in Korea (Gangwon-do, Gyeonggi-do, Chungcheongbuk-do, Jeollabuk-do, Gyeongnam-do, and Jeju-do) from 2008 to 2009. The 'Chunpungjeokchukmyeon' has gray seed color and traverse elliptic leaves. The type of matured stage is medium shape between 'chukmyeon' and 'chima' leaf lettuce. Compared to 'Dukseomjeokchukmyeon', marketable yield of 'Chunpungjeokchukmyeon' was higher by 6% (at 372 g per plant) and 'Chunpungjeokchukmyeon' has particularly improved expression of deep red leaf color in high temperature cultivation in the field. The shelf-life of 'Chunpungjeokchukmyeon' was three weeks longer than 'Dukseomjeokchukmyeon' at 4$^{\circ}C$. The anthocyanin content of 'Chunpungjeokchukmyeon' was higher than that of 'Dukseomjeokchukmyeon' with 17.5 mg/100g. The BSL (latucin+8-deoxylactucin+lactucopicrin) content of 'Chunpungjeokchukmyeon' is lower than that of 'Dukseomjeokchukmyeon'. Furthermore, its taste is better, more crispy, and sweeter than those of 'Dukseomjeokchukmyeon'. So we recommend that new cultivar 'Chunpungjeokchukmyeon' can be suitable for cultivation in spring season than summer season.

• Journal of KIISE:Databases
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• v.34 no.6
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• pp.546-553
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• 2007

As ontologies are used widely, interest for semantic similarity search is also increasing. In this paper, we suggest a query evaluation scheme for k-nearest neighbor query, which retrieves k most similar objects to the query object. We use the best match method to calculate the semantic similarity between objects and use the signature tree to index annotation information of objects in database. The signature tree is usually used for the set similarity search. When we use the signature tree in similarity search, we are required to predict the upper-bound of similarity for a node; the highest similarity value which can be found when we traverse into the node. So we suggest a prediction function for the best match similarity function and prove the correctness of the prediction. And we modify the original signature tree structure for same signatures not to be stored redundantly. This improved structure of signature tree not only reduces the size of signature tree but also increases the efficiency of query evaluation. We use the Gene Ontology(GO) for our experiments, which provides large ontologies and large amount of annotation data. Using GO, we show that proposed method improves query efficiency and present several experimental results varying the page size and using several node-splitting methods.