• 한국산림과학회지
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• 제82권1호
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• pp.34-43
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• 1993

이 논문에서는 고정식 가선집재기를 중심으로 집재작업의 구조적 특성을 역학적 원리를 이용하여 해석하였다. 그리고 집재지의 지형여건, 시스템의 기하학적 형태 및 작업조건과의 함수관계에서 최대허용반송용량을 추정하기 위한 함수관계식을 힘과 모멘트의 평형조건으로부터 유도하는 과정을 제시하였다. 이러한 관계식 중에는 벌도목의 들어올려진 정도와 단선구조 cable 철선의 역학적 해석을 위한 기본 관계식들이 포함되었고, 단선구조 역학해석은 현수선원리를 기초로 하여 단선의 처짐이 고려되었다. 역학관계식들은 복잡한 비선형함수식들로 구성되어 이를 풀기 위한 과정을 제시하기 위하여 전산모델을 개발하였다, 이 모델에서는 계산목적상 Secant기법을 이용하였다. 또한 가상적인 데이타를 이용하여 전산모델의 적용예를 제시하였다.

• 한국철도학회논문집
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• 제13권6호
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• pp.570-576
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• 2010

본 논문에서 우리는 Petri Net을 사용하여 철도 선로를 모형화 하는 문제를 다루었다. Petri Net는 병행적, 비동기, 분산, 병렬, 비결정론, 확률론 등의 특성을 가진 정보처리시스템을 기술하고 시스템의 동적거동의 특성을 연구하기 위해 고안된 도식적, 수학적 모델링 도구이다. 검증 사례로서, 한국형 경량전철시험선 선로를 철도 시설물의 구성품(세그먼트, 궤도, 분기기, 승강장)으로 모델링하고, 대피선이 있는 단일 궤도에서 두 대의 열차가 동일한 방향에서 함께 진행하고 있거나 반대방향에서 동시에 진행을 하지만 충돌을 하지 않는다는 것을 보장하면서 설정된 진로를 이동하는 Peri Net 모형을 구현하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.783-785
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• 2003

In recent years, the use of video in GIS is considered to be an important subject and many related studies result in VideoGIS. The virtual navigation is an important function that can be applied to various VideoGIS applications. For virtual navigation by video, the following problems must be solved. 1) Because the video route may be not exactly coincided with route that user wants to navigate, parts of several video clips may be required for single navigation. Virtual navigation should allow the user to move from one video to another at the proper position. We suggest the video segmentation method based on geographic data combined with video. 2) From a point to a destination, the change frequency of video must be minimized. The frequent change of video make user to mislead navigation route and cause the wasteful use of computing resource. We suggest methods that structure video segments and calculate weight value of each node and link.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권7호
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• pp.3369-3385
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• 2019

There are various research challenges in vehicular ad hoc networks (VANETs) that need to be focused until an extensive deployment of it becomes conceivable. Design and development of a scalable routing algorithm for VANETs is one of the critical issue due to frequent path disruptions caused by the vehicle's mobility. This study aims to provide a novel road-aware routing protocol for vehicular networks named as Two-level hierarchical Hybrid Road-Aware (THERA) routing for vehicular ad hoc networks. The proposed protocol is designed explicitly for inter-vehicle communication. In THERA, roads are distributed into non-overlapping road segments to reduce the routing overhead. Unlike other protocols, discovery process does not flood the network with packet broadcasts. Instead, THERA uses the concept of Gateway Vehicles (GV) for the discovery process. In addition, a route between source and destination is flexible to changing topology, as THERA only requires road segment ID and destination ID for the communication. Furthermore, Road-Aware routing reduces the traffic congestion, bypasses the single point of failure, and facilitates the network management. Finally yet importantly, this paper also proposes a probabilistical model to estimate a path duration for each road segment using the highway mobility model. The flexibility of the proposed protocol is evaluated by performing extensive simulations in NS3. We have used SUMO simulator to generate real time vehicular traffic on the roads of Gangnam, South Korea. Comparative analysis of the results confirm that routing overhead for maintaining the network topology is smaller than few previously proposed routing algorithms.

• 말소리와 음성과학
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• 제10권4호
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• pp.31-37
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• 2018

Pitch trajectories reflect a continuous variation of vocal fold movements over time. This study examined the pitch trajectories of English vowels produced by 139 American English speakers, statistically analyzing their trajectories using the Generalized Additive Mixed Models (GAMMs). First, Praat was used to read the sound data of Hillenbrand et al. (1995). A pitch analysis script was then prepared, and six pitch values at the corresponding time points within each vowel segment were collected and checked. The results showed that the group of men produced the lowest pitch trajectories, followed by the groups of women, boys, then girls. The density line showed a bimodal distribution. The pitch values at the six corresponding time points formed a single dip, which changed gradually across the vowel segment from 204 to 193 to 196 Hz. The normality tests performed on the pitch data rejected the null hypothesis. Nonparametric tests were therefore conducted to discover the significant differences in the values among the four groups. The GAMMs, which analyzed all the pitch data, produced significant results among the pitch values at the six corresponding time points but not between the two groups of boys and girls. The GAMMs also revealed that the two groups were significantly different only at the first and second time points. Accordingly, the methodology of this study and its findings may be applicable to future studies comparing curvilinear data sets elicited by experimental conditions.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2009년도 학술대회
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• pp.193-196
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• 2009

단일 영상에서 피부색 영역을 추출하기 위해서 기존의 많은 방법들이 하나의 고정된 피부색 모델을 사용한다. 그러나 영상에 특성에 따라 영상에 포함된 피부색의 분포가 다양하기 때문에 이러한 방법을 이용하여 피부색을 검출할 경우 낮은 검출율이나 높은 긍정 오류율이 발생할 수 있다. 따라서 영상의 특징에 따라 적응적으로 피부색 영역을 추출할 수 있는 방법이 필요하다. 이에 본 논문에서는 영상의 특징에 따라 2단계의 과정을 거쳐 피부색 모델을 수정하는 방법으로, 다양한 조명과 환경 조건에서 높은 검출율과 낮은 긍정 오류율을 동시에 가지는 알고리즘을 제안한다.

• 생약학회지
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• 제27권4호
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• pp.359-365
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• 1996

In order to product the saikosaponin which is one of the secondary product from Bupleurum falcatum efficiently through the tissue culture, several levels of agar and gellan gum as the gelling agent, 2,4-D as the growth regulator, and L-phenylalanine as the precursor were used with single or combination treatment on MS basal medium. Gellan gum was more effective than agar as the gelling agent in fresh and dry weight increase of callus induced from Bupleurum falcatum leaf segment. Gellan gum medium supplemented with L-phenylalanine produced 1.6 times of fresh weight more than that of agar. The fresh weight was remarkably high in gellan gum when the calli was treated with the combination of 2,4-D and L-phenylalanine similar to the single treatment of 2,4-D or L-phenylalanine. However, the saikosaponin content in callus was high in gellan gum with the single treatment of L-phenylalanine. Especially, the saikosaponin content in gellan gum supplemented with 1.0mg/L L-phenylalanine was 2 times(2.4 mg/g) higher than that in agar medium supplemented with 0.1 mg/L 2,4-D(0.9 mg/g).

• 한국임상수의학회지
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• 제33권2호
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• pp.124-128
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• 2016

A 7-year-old intact female Maltese dog presented with a history of bite wounds. Physical examination revealed labored breathing, four puncture wounds with subcutaneous emphysema of the thorax, and paradoxical respiratory movement of the right thoracic wall. On radiography, a segmental fracture of the right 7th rib and a single fracture of the 8th rib were evident on the dorsal thorax. An inward displacement of the fractured segment and contusion of the right caudal lung lobe were identified with computed tomography. A diagnosis of pseudo-flail chest was made. Exploratory thoracotomy revealed a full-thickness muscular defect, a marked discoloration of the right caudal lung lobe, a segmental fracture of the right 7th rib, and a single fracture of the right 8th rib. Necrotic tissues were removed using surgical debridement. The fractured 7th and 8th ribs were corrected using a single interfragmentary wiring technique. The thoracic wall was reconstructed using the latissimus dorsi muscle flap. Additional thoracic stabilization using a thermoplastic splint was applied to correct paradoxical respiratory movement. The external splint was removed 4 weeks postoperatively. There was no evidence of respiratory abnormalities 18 months postoperatively.

• 한국식생활문화학회지
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• 제37권4호
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• pp.324-334
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• 2022

This study was conducted to provide basic data for product development and marketing strategies for the Thai home meal replacement (HMR) market, to reflect the changing trends in household sizes in Thailand. The results of analyzing the characteristics and differences of HMR consumption behavior between single-person households and multi-person households in Thailand were as follows: It was found that single-person households use HMR to save money and for the convenience in cooking and preparation. In the preference by HMR type, multi-person households showed a higher preference for all types of products than single-person households. Thai consumers, regardless of their household size, mainly use department stores and large shopping malls to purchase HMR, and they most prefer to get information through Internet advertisements. The shelf life, quality, taste, hygiene, and freshness of HMR were the main considerations for their selection. Based on the results of this study, the Thai market requires the development of HMR products that are reasonable in terms of cost and preparation time. In addition, it is necessary to develop products that can satisfy consumer needs, such as nutritional enhancement and therapeutic foods, products that are organic, eco-friendly, cater to various menus, and address the premium segment.

• Journal of Korean Neurosurgical Society
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• 제54권6호
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• pp.496-500
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• 2013

Objective : To evaluate the successful fusion rate in postmenopausal women with single-level anterior cervical discectomy and successful fusion (ACDF) and identify the significant factors related to bone successful fusion in pre- and postmenopausal women. Methods : From July 2004 to December 2010, 108 consecutive patients who underwent single-level ACDF were prospectively selected as candidates. Among these, the charts and radiological data of 39 women were reviewed retrospectively. These 39 women were divided into two groups : a premenopausal group (n=11) and a postmenopausal group (n=28). To evaluate the significant factors affecting the successful fusion rate, the following were analyzed : the presence of successful fusion, successful fusion type, age, operated level, bone mineral density, graft materials, stand-alone cage or plating with autologous iliac bone, subsidence, adjacent segment degeneration, smoking, diabetes mellitus, and renal disease. Results : The successful fusion rates of the pre- and postmenopausal groups were 90.9% and 89.2%, respectively. There was no significant difference in the successful fusion rate or successful fusion type between the two groups. In the postmenopausal group, three patients (10.8%) had successful fusion failure. In the postmenopausal group, age and subsidence significantly affected the successful fusion rate (p=0.016 and 0.011, respectively), and the incidence of subsidence in patients with a cage was higher than that in patients with a plate (p=0.030). Conclusion : Menopausal status did not significantly affect bone successful fusion in patients with single-level ACDF. However, in older women with single-level ACDF, the combination of use of a cage and subsidence may unfavorably affect successful fusion.