• Journal of Ecology and Environment
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• v.34 no.2
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• pp.167-174
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• 2011

Black-billed magpies (Pica pica) are a highly sedentary species due to their short and round wings, which are not adequate for long distance flights. We investigated geographic variation in the vocal signals of magpies residing in South Korea and Japan (subspecies sericea). Based on the magpie's limited dispersal ability, we predicted that the variation in vocal signals of black-billed magpies could be explained by geographic barriers such as mountain ranges and straits. We analyzed four-syllable chatter calls of magpies from five localities in South Korea, which are separated by mountain ranges (Seoul, Daejeon, Daegu, Gwangju, and Busan), and two island localities separated from the mainland by straits (Jeju in Korea and Saga in Japan). We found significant differences in the characteristics of magpie chatter calls recorded in the seven localities, and the variation pattern was independent among the variables. Mainland-island differentiation and north-south differentiation were observed. In general, magpies on Saga were the most distinctive. North-south differentiation was observed among the Korean mainland localities. However, the pattern was not related to the presence of putative geographic barriers. We hypothesize that the patterns of geographic variation in the structure of magpie chatter calls residing in South Korea might have been shaped by a sudden expansion of magpies followed by low level of local isolation, which may have led to vocal differentiation. Along with elucidating the vocal environment of Korean magpie populations, more extensive sampling is needed to clarify the functional aspects of geographic variation in the vocal signals of Korean magpies.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.41.1-41.1
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• 2013

To test whether the close relationships between host and satellite galaxies in isolated groups are also found in the harsh environment of a galaxy cluster, we carry out a case study of WHL 085910.0+294957, a galaxy cluster at z=0.30, using deep images obtained with the 2.1-m Otto Struve telescope and CQUEAN CCD camera. When environmental parameters are controlled, the local weighted mean color of faint galaxies shows a measurable correlation with the color of their bright ($M_i$ < -18) neighbor. The most striking result is that the red (r - i > 0.2) and bright galaxies within 200 kpc distance from the center of the cluster are correlated in color with very faint ($M_i$ > -14) galaxies around them by $(r-i)_{satellites}=(7.276{\pm}1.402){\times}(r-i)_{host}-2.434$ (correlation coefficient = 0.665). We suggest three scenarios to interpret the results: vestiges of infallen groups, dwarf capturing, and tidal tearing of bright galaxies.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.8 s.227
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• pp.895-901
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• 2004

Single-phase convection and nucleate boiling heat transfer were locally investigated for confined planar water jets. The detailed distributions of the wall temperature and the convection coefficient as well as the typical boiling curves were discussed. The curve for the single-phase convection indicated the developing laminar boundary layer, accompanied by monotonic increase of the wall temperature in the stream direction. Boiling was initiated from the furthest downstream as heat flux increased. Heat transfer variation according to the streamwise location was reduced as heat flux increased enough to create the vigorous nucleate boiling. Velocity effects were considered for the confined free-surface jet. Higher velocity of the jet caused the boiling incipient to be delayed more. The transition to turbulence precipitated by the bubble-induced disturbance was obvious only for the highest velocity, which enabled the boiling incipient to start in the middle of the heated surface, rather than the furthest downstream as was the case of the moderate and low velocities. The temperature at offset line were somewhat tower than those at the centerline for single-phase convection and partial boiling, and these differences were reduced as the nucleate boiling developed. For the region prior to transition, the convection coefficient distributions were similar in both cases while the temperatures were somewhat lower in the submerged jet. For single-phase convection, transition was initiated at $x/W{\cong}2.5$ and completed soon for the submerged jet, but the onset of transition was retarded to the distance at $x/W{\cong}6$ for the fee-surface jet.

• Journal of Biosystems Engineering
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• v.40 no.4
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• pp.409-416
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• 2015

Purpose: This study evaluates a new banana bulk packaging method under the real transport conditions of Sri Lanka. Methods: A field evaluation of optimized 8-mm thick Styrofoam sheets used as the cushioning material was applied. A trial transport was conducted from Thambuttegama to Colombo using a medium-sized open truck, with banana leaves as the control material. Data were recorded at the farmer, transporter, retailer, and consumer stages of the supply chain. Mechanical damage, physiological loss in weight, fruit firmness, total soluble solids, ripeness index, visual quality ratings, and the physical damage index of the bananas were measured at each stage. A cost-benefit analysis was also conducted for both packaging methods. Results: The 8-mm styrofoam sheets significantly reduced (p < 0.05) the mechanical damage from 26.3% to 12.9% compared to the conventional method for long-distance transport, and the physiological loss in weight showed a decrease of 2.88%. The loss of firmness of the fruits followed a simmilar pattern for both methods until reaching the retailer, but at the consumer was significantly higher (p < 0.05) for the control. However, the physical damage index at the retail stage for the control showed symptoms of physical injury, whereas the bananas transported using the cushioning materials exhibited only minor symptoms. Further, the visual quality of the fruits after transport from the farmer to the consumer was preserved, which is one of the main factors affecting consumer preference and retail price. The proposed method increases the profit margin by 51.2% for Embul bananas owing to the reduced postharvest losses. Conclusion: The 8-mm thick Styrofoam sheets reduced the physical damage to the bananas, with the quality parameters maintained at the prefered level. Moreover, profits may be increased.

• Archives of Plastic Surgery
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• v.41 no.6
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• pp.709-715
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• 2014

Background The distally based sural artery flap is a reliable, local reconstructive option for small soft tissue defects of the distal third of the leg. The purpose of this study is to describe an adipofascial flap based on a single sural nerve branch without sacrificing the entire sural nerve, thereby preserving sensibility of the lateral foot. Methods The posterior aspect of the lower limb was dissected in 15 cadaveric limbs. Four patients with soft tissue defects over the tendo-achilles and ankle underwent reconstruction using the adipofascial flap, which incorporated the distal peroneal perforator, short saphenous vein, and a single branch of the sural nerve. Results From the anatomical study, the distal peroneal perforator was situated at an average of 6.2 cm (2.5-12 cm) from the distal tip of the lateral malleolus. The medial and lateral sural nerve branches ran subfascially and pierced the muscle fascia 16 cm (14-19 cm) proximal to the lateral malleolus to enter the subcutaneous plane. They merged 1-2 cm distal to the subcutaneous entry point to form the common sural nerve at a mean distance of 14.5 cm (11.5-18 cm) proximal to the lateral malleolus. This merging point determined the pivot point of the flap. In the clinical cases, all patients reported near complete recovery of sensation over the lateral foot six months after surgery. All donor sites healed well with a full range of motion over the foot and ankle. Conclusions The distally based sural artery adipofascial flap allowed for minimal sensory loss, a good range of motion, an aesthetically acceptable outcome and can be performed by a single surgeon in under 2 hours.

• Journal of Korean Society of Transportation
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• v.19 no.3
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• pp.19-32
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• 2001

A parking facility choice model. which can be applied to analyze of the driver's parking behavioral changes in response to the local government's parking policy changes and to predict parking demand by the facility types, is developed. Under the context of the stated preference discrete choice model, socioeconomic variables and parking alternative characteristic variables are introduced as explanatory variables. A parking facility choice model for the shopping trip purpose is derived using multinomial logit model and nested logit model and the stated preference data collected in Taegu metropolitan area. The result shows that the sign of all the estimated parameters are logically consistent and the model's goodness of fit is reasonably good. As a result of the elasticity analysis of the model, the elasticity of parking cost is highest, and the elasticity of walking distance between parking place and the destination is higher than parking place searching and ingress time. This means that the parking places are supplied around the destination in the form of small-size parking place. The findings in this study is expected to provide a fundamental data for various short-term parking policy analyses and for parking facility's demand estimations.

• Journal of Korea Multimedia Society
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• v.10 no.1
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• pp.74-82
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• 2007

IPv6 is the internet protocol for next generation which can solve the problem of IPv4 protocol. Mobile IPv6 efficiently provides the mobility for mobile devices holding the properties of IPv6. iSCSI(Internet Small Computer System Interface) is a block-oriented storage access protocol that enables a user to recognize a remote storage as their own local block device through general TCP/IP networks. Since iSCSI uses a standard Ethernet switch and router for this kind of access, it can not only be applized to Ethernet technologies, but can also be used to create a storage networking system without any distance restrictions that can equally be applied to a wireless network environment. Accordingly, this paper presents an alternative approach to overcome the limited storage space of mobile devices based on the IPv6 iSCSI initiator driver which was originally designed for wired networks. Also, this paper describes about the implementation and performance analysis of mobile education service system using virtual storage devices in IPv6 wireless networks.

• Journal of Korea Multimedia Society
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• v.14 no.6
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• pp.742-751
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• 2011

This paper presents a robust 3D model hashing dependent on key and parameter by using heat kernel signature (HKS), which is special shape feature descriptor, In the proposed hashing, we calculate HKS coefficients of local and global time scales from eigenvalue and eigenvector of Mesh Laplace operator and cluster pairs of HKS coefficients to 2D square cells and calculate feature coefficients by the distance weights of pairs of HKS coefficients on each cell. Then we generate the binary hash through binarizing the intermediate hash that is the combination of the feature coefficients and the random coefficients. In our experiment, we evaluated the robustness against geometrical and topological attacks and the uniqueness of key and model and also evaluated the model space by estimating the attack intensity that can authenticate 3D model. Experimental results verified that the proposed scheme has more the improved performance than the conventional hashing on the robustness, uniqueness, model space.

• Journal of KIISE
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• v.42 no.6
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• pp.699-706
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• 2015

In recent years, as near-duplicate image has been increasing explosively by the spread of Internet and image-editing technology that allows easy access to image contents, related research has been done briskly. However, BoF (Bag-of-Feature), the most frequently used method for near-duplicate image detection, can cause problems that distinguish the same features from different features or the different features from same features in the quantization process of approximating a high-level local features to low-level. Therefore, a post-verification method for BoF is required to overcome the limitation of vector quantization. In this paper, we proposed and analyzed the performance of a post-verification method for BoF, which converts SIFT (Scale Invariant Feature Transform) descriptors into 128 bits binary codes and compares binary distance regarding of a short ranked list by BoF using the codes. Through an experiment using 1500 original images, it was shown that the near-duplicate detection accuracy was improved by approximately 4% over the previous BoF method.

• Journal of environmental and Sanitary engineering
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• v.18 no.3 s.49
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• pp.1-10
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• 2003

This study was aimed to investigate the influence on the vicinity by air pollutant generated from facility of the district heating located in local small town. We selected the seven areas arround the surroundings of facility of the district heating, compared the air quality evaluated before and after operations of the facility, and estimated the diffusion of air pollutant exhausted from the facility using a ISC model. The result was that the concentration of TSP before and after operations of the facility was 89${\sim}$94${\mu}$g/m$^3$,and 72${\sim}$81${\mu}$g/m$^3$, respectively and the latter showed a decline in concentration. Also, there was no relationship between straight distance from the facility of the district heating and the concentration of TSP. This result was applicable to cases of PM-10 and SO$_2$. We also investigated the influence on the air around the neighbored area by air pollutant produced from facility of the district heating using ISCLT3 model. The adding-concentrations of TSP, SO$_2$,NO$_2$, and CO were 0.0019${\sim}$0.00183${\mu}$g/m$^3$, 0.0029${\sim}$0.5648ppb, 0.2924${\sim}$l.9837ppb,and 0.0087${\sim}$0.0590ppb, respectively. It is predicted that each concentration is added to pollutant exhausted from facility of the district heating and is about 1/100${\sim}$1/180,000 of present air quality. This has a tiny influence on general air quality. According to this analysis, the concentration of air pollutant is less effected to pollutants expected by the facility of the district heating than other pollutants emitted from mobil source or industrial complex, and etc.