An On-Demand Routing Algorithm for Mobile Wireless Networks

Yan, Huai-Zhi,Ajith P.K,Park, Dong-Won,Joo, Gi-Ho 배재대학교 공학연구소 2005 공학논문집 Vol.7 No.1

An ad hoc network is a collection of wireless mobile nodes forming a temporary network without the centralized administration. Due to the limited transmission range of wireless work interface, multiple networks “hops” maybe needed for one node to exchange data with adjacent node. In recent years, a variety of new routing protocol about ad hoc network was developed. This paper presents a new routing protocol based on the Dynamic Source Routing which is not suitable for the high mobility ad hoc network. The Enhanced DSR adapts quickly to routing changes when node movement is frequent. When a trunk route is broken, this protocol will utilize the alternative route saved in the route to discovery quickly the new route. It improves the performance of the existing DSR algorithm, so that the negative impacts from weakness of DSR are reduced.

롤러스케이트 선수의 운동상해발생과 예방에 대한 조사 연구

김동희,김도수,채양석,이하얀,김선호,조성채 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.1

The study was intended to research the fact of roller skate players injury. For the study, kinds and parts of injuries, skills to be hurted, facility, injured time, cause, remedy, mental response and protecting were investigated through 182 roller skate players. The results were as follows : 1. The injury body part was showed that leg was the highest and followed by knee and ankle. 2. In the cause of injury was showed as follows: skills on corner work, bank track with concrete, 200m distance. 3. In the general cause of injury was showed: chronic fatigue by over training. 4. In the treatment and participation period after injury outbreak were showed: treatment period was toward the inside 1 week and participation to play during the treatment. 5. To the injury prevention players responded warm up, and cool down and mental-concentration were needed. Supervisor, coach and players responded knee protector wearing was needed in elementary school players and helmet-chin protector wearing in general players. The game rule revision was not necessary and the agree and disagree for ground unity to resemble. Almost players to be like concrete ground.

자외선 (UVB) 노출 증가에 대한 피부암 위해도 예측 모델의 적용

신동천,이종태,정용,강나경,양지연 한국환경독성학회 1996 환경독성보건학회지 Vol.11 No.1

A decrease in stratospheric ozone probably caused by chloroflurocarbons (CFCs) emissions, has been observed large parts of the globe. It is generally accepted that if ozone levels in the stratosphere are depleted, greater amounts of shortwave ultraviolet radiation-B (UVB) will reach the earth's surface, resulting in increased incidence of nonmelanoma skin cancer. In this study, we evaluated several mathematical models, such as a power and an exponential model, and a geometric model considering the surface area of a human body part and ages for the prediction of skin cancer incidence caused by exposure to the UVB radiation. These models basically estimated the risk of skin cancer based on those measurements of the local ozone in stratosphere and UVB. Both were measured at a part of Seoul with a Dobson ozone spectrometer and Robertson-Berger UV Biometer for 1995. As a result, we calculated the point estimation applying a biological amplification factor (BAF), UVB radiation and other factors. We used a Monte-Carlo simulation technique with assumption on the distribution of each considered factor. The sensitivity analysis of model by there components conducted using Gaussian sensitivity method. The annual integral of UVB radiation was 2275 MED (minimal erythema dose)/yr. Also, an estimate of the annual amount of UVB reaching the earth's surface at a korea's latitude and altitude was 3328 MED/yr. The values of the radiation amplification factor (RAF) were ranged from 0.9 to 1.5 in Seoul. To give the effective factors required to model the prediction of skin cancer incidence caused by exposure to the UVB radiation in Korea, we studied the pros and cons of above mentioned models with the application of those parameters measured in Seoul, Korea.

알데히드탈수소효소 2(ALDH2) 및 CYP2E1 유전자 다형성에 따른 요중 뮤콘산 농도와 요중 8-hydroxydeoxyguanosine과의 관련성

김용대,강종원,엄상용,장연위,김성훈,김은영,이철호,문재동,김헌 대한산업의학회 2007 대한직업환경의학회지 Vol.19 No.2

Life Science : Evaluation of physicochemical properties, skin permeation and accumulation profiles of salicylic acid amide prodrugs as sunscreen agent

( Yi Dong Yan ),( Jun Ho Sung ),( Dong Won Lee ),( Jung Su Kim ),( Eun Mi Jeon ),( Dae Duk Kim ),( Dong Wuk Kim ),( Jong Oh Kim ),( Ming Guan Piao ),( Dong Xun Li ),( Chul Soon Yong ),( Han Gon Choi ) 영남대학교 약품개발연구소 2012 영남대학교 약품개발연구소 연구업적집 Vol.22 No.0

Various amide prodrugs of salicylic acid were synthesised, and their physicochemical propertiesincluding lipophilicity, chemical stability and enzymatic hydrolysis were investigated. In vivo skinpermeation and accumulation profiles were also evaluated using a combination of common permeationenhancing techniques such as the use of a supersaturated solution of permeants in an enhancer vehicle, a lipophilic receptor solution, removal of the stratum corneum and delipidisation of skin. Their capacity factor values were proportional to the degree of carbon-carbon saturation in the side chain. All these amides were highly stable in acetonitrile and glycerine. Amide prodrugs were converted tosalicylic acid both in hairless mouse liver and skin homogenates. N-dodecyl salicylamide (C12SM) showed the lowest permeation of salicylic acid in skin compared to the other prodrugs, probably due to its low aqueous solubility. It had a high affinity for the stratum corneum and its accumulation was restricted to only the uppermost layer of skin. Thus, this amide prodrug could be a safer topicalsunscreen agent with minimum potential for systemic absorption.ⓒ2011 Elsevier B.V.All rights reserved.

Roles of Immunohistochemical Staining in Diagnosing Pulmonary Squamous Cell Carcinoma

Yan, Yue,Zhang, Ya-Xiong,Fang, Wen-Feng,Kang, Shi-Yang,Zhan, Jian-Hua,Chen, Nan,Hong, Shao-Dong,Liang, Wen-Hua,Tang, Yan-Na,He, Da-Cheng,Wu, Xuan,Zhang, Li Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.2

Background: Differentiating morphologic features based on hematoxylin-eosin (HE) staining is the most common method to classify pathological subtypes of non-small-cell lung cancer (NSCLC). However, its accuracy and inter-observer reproducibility in pathological diagnosis of poorly differentiated NSCLC remained to be improved. Materials and Methods: We attempted to explore the role of immunohistochemistry (IHC) staining in diagnosing pulmonary squamous cell carcinoma (SQCC) with poorly differentiated features by HE staining or with elevated serum adenocarcinoma-specific tumor markers (AD-TMs). We also compared the difference of epidermal growth factor receptor (EGFR) mutation rate between patients with confirmed SQCC and those with revised pathological subtype. Logistic regression analyses were used to test the association between different factors and diagnostic accuracy. Results: A total of 132 patients who met the eligible criteria and had adequate specimens for IHC confirmation were included. Pathological revised cases in poor differentiated subgroup, biopsy samples and high-level AD-TMs cases were more than those with high/moderate differentiation, surgical specimens and normal-level AD-TMs. Moreover, biopsy sample was a significant factor decreasing diagnostic accuracy of pathological subtype (OR, 4.037; 95% CI 1.446-11.267, p=0.008). Additionally, EGFR mutation rate was higher in patients with pathological diagnostic changes than those with confirmed SQCC (16.7% vs 4.4%, p=0.157). Conclusions: Diagnosis based on HE staining only might cause pathological misinterpretation in NSCLC patients with poor differentiation or high-level AD-TMs, especially those with biopsy samples. HE staining and IHC should be combined as pathological diagnostic standard. The occurrence of EGFR mutations in pulmonary SQCC might be overestimated.

Cucumber Growth and Nitrogen Uptake as Affected by Solution Temperature and NO₃^-:NH₄⁺ Ratios during the Seedling

Yan, Qiu-Yan,Duan, Zeng-Qiang,Li, Jun-Hui,Li, Xun,Dong, Jin-Long Korean Society of Horticultural Science 2013 원예과학기술지 Vol.31 No.4

The effect of solution temperature and nitrogen form on cucumber (Cucumis sativus L.) growth, photosynthesis and nitrogen metabolism was investigated in hydroponic culture. Cucumber plants were grown for 35 days in a greenhouse at three constant solution temperatures ($15^{\circ}C$, $20^{\circ}C$, and $25^{\circ}C$) within a natural aerial temperature ($15-30^{\circ}C$). Four nitrate:ammonium ($NO{_3}^-:NH{_4}^+$) ratios (10:0, 8:2, 5:5, and 2:8 $mmol{\cdot}L^{-1}$) at constant nitrogen (N) concentration of $10mmol{\cdot}L^{-1}$ were applied within each solution temperature treatment. Results showed an increasing solution temperature enhanced plant growth (height, dry weight, and leaf area) in most N treatments. Dry weight accumulation was greatest at the 10:0 $NO{_3}^-:NH{_4}^+$ ratio in the $15^{\circ}C$ solution, the 5:5 ratio in the $20^{\circ}C$ solution and the 8:2 ratio in the $25^{\circ}C$ solution. Photosynthetic rate (Pn) response to solution temperature and $NO{_3}^-:NH{_4}^+$ ratio was similar to that of plant growth. Probably, the photosynthate shortage played a role in the reduced biomass formation. Increasing solution temperature enhanced the nitrate reductase (NR) activity, and further reduced shoots nitrate content. Our results indicate that the optimal ratio of nitrate to ammonium that promotes growth in hydroponic cucumber varies with solution temperature.

기대충족모델을 이용한 VR 관광콘텐츠 이용객의 지속사용의도: VR 관광 경험 있는 중국인을 대상으로

Yan-Dong Han,김영국 사단법인 한국융합기술연구학회 2023 아시아태평양융합연구교류논문지 Vol.9 No.3

With the development of ICT (information & communications technology), new technology-based VR Contents provided to tourists are attracting great attention. This study attempts to analyze the user's behavior and intention to use VR Contents by applying the Expectation Satisfaction Model to the intention to continue using VR Tourism Contents. Thus, the purpose of this study was to investigate the relationships between expectations, perceived usefulness, satisfaction, and intention to continue using virtual reality tourism contents experiencers in China. To achieve the study’s aim, previous studies were reviewed and the contents of the tourism industry using virtual reality technology were reviewed. The questionnaire was constructed based on past studies, and the questionnaire was completed after expert review and preliminary survey. An online survey was conducted on Chinese users with experience in VR Tourism Content. The main survey was conducted by convenience sampling method for 14 days from November 14 to 27, 2022, targeting Chinese people who used VR tourism contents. After confirming the reliability and validity of the research model, all hypotheses presented were found to be statistically significant. Based on the results of this study, the academic and practical implications of the study were discussed. Also, research limitation and future research were presented. 정보통신기술(ICT)의 발달로 관광객들에게 제공되는 신기술 기반의 VR 콘텐츠가 큰 주목을 받고 있다. 본 연구는 VR 관광콘텐츠의 지속이용의도에 기대충족모형을 적용하여 사용자의 행동과 VR 콘텐츠에 대한 지속적 이용의도를 분석하고자 한다. 따라서 본 연구의 목적은 중국 가상현실 관광콘텐츠 체험자의 기대충족, 지각된 유용성, 만족도, 지속사용의도 사이의 영향관계를 검증하고자 하였다. 따라서 본 연구의 목적 달성을 위해 선행연구를 검토하고 가상현실기술을 활용한 관광산업에 대한 내용을 검정하였다. 선행연구를 바탕으로 설문지를 구성하였고, 전문가 검토 및 예비조사를 거쳐 설문지가 완성되었다. 연구대상은 VR 관광콘텐츠 경험이 있는 중국 사용자로 설정하였다. 본 조사는 VR 관광콘텐츠를 이용해 본 중국인을 대상으로 2022년 11월 14일부터 11월 27일까지 14일간 편의표본추출 방법으로 설문을 실시하였다. 연구모형의 신뢰성과 타당성을 확인한 후 제시된 모든 가설이 통계적으로 유의미한 것으로 나타났다. 본 연구의 결과를 바탕으로 연구의 학문적·실무적 시사점을 논의하였고 연구의 한계와 향후 연구도 제시하였다.

AlGaN/GaN heterostructure pH sensor with multi-sensing segments

Dong, Yan,Son, Dong-hyeok,Dai, Quan,Lee, Jun-Hyeok,Won, Chul-Ho,Kim, Jeong-Gil,Kang, Seung-Hyeon,Lee, Jung-Hee,Chen, Dunjun,Lu, Hai,Zhang, Rong,Zheng, Youdou Elsevier 2018 Sensors and actuators. B, Chemical Vol.260 No.-

<P><B>Abstract</B></P> <P>pH sensor is very important in various fields, and has triggered many types of devices based on different materials and mechanisms. How to improve the performances of the sensors is one of major challenges now. In the present paper, we developed an idea to improve the sensitivity of pH sensors based on AlGaN/GaN high-electron-mobility transistors (HEMTs) by introducing multi-sensing segments, and experimentally fabricated prototype devicesand then investigated their responses to aqueous solutions under different pH values. The optimized sensor exhibits a very high linear sensitivity of 1.35 mA/pH at drain-source voltage of 1.5 V, which is much higher than those of conventional pH sensors with single open gate sensing area. This indicates that the multi-sensing segments is very effective in increasing the sensitivity of the pH sensor, rather than simply increasing the sensing area. The sensors degrade after measurement in solution for a long working time, but they can recover to their initial states in a certain duration after washing, typically ∼24 h. Our finding paves new strategy for the future design of high sensitive and stable pH sensors based on HEMTs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Novel multi-sensing segments pH sensor is designed and fabricated by using AlGaN/GaN high electron mobility transistor. </LI> <LI> Realizing very high sensitivity on the multi-sensing sensor, which is much higher than that of conventional geometric pH sensor. </LI> <LI> Achieved excellent performance stability with good recovery feature on the multi-sensing sensor. </LI> </UL> </P>

¿Por que clamamos el retorno de don Quijote?

( Yan Sheng Dong ) 한국스페인어문학회 2005 스페인어문학 Vol.0 No.37