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.

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.

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.

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

Sensory involvement in the SOD1-G93A mouse model of amyotrophic lateral sclerosis

Yan-Su Guo,Dong-Xia Wu,Hong-Ran Wu,Shu-Yu Wu,Cheng Yang,Bin Li,Hui Bu,Yue-sheng Zhang,Chun-Yan Li 생화학분자생물학회 2009 Experimental and molecular medicine Vol.41 No.3

A subset of patients of amyotrophic lateral sclerosis (ALS) present with mutation of Cu/Zn superoxide dismutase 1 (SOD1), and such mutants caused an ALSlike disorder when expressed in rodents. These findings implicated SOD1 in ALS pathogenesis and made the transgenic animals a widely used ALS model. However, previous studies of these animals have focused largely on motor neuron damage. We report herein that the spinal cords of mice expressing a human SOD1 mutant (hSOD1-G93A), besides showing typical destruction of motor neurons and axons, exhibit significant damage in the sensory system, including Wallerian-like degeneration in axons of dorsal root and dorsal funiculus, and mitochondrial damage in dorsal root ganglia neurons. Thus, hSOD1-G93A mutation causes both motor and sensory neuropathies, and as such the disease developed in the transgenic mice very closely resembles human ALS. A subset of patients of amyotrophic lateral sclerosis (ALS) present with mutation of Cu/Zn superoxide dismutase 1 (SOD1), and such mutants caused an ALSlike disorder when expressed in rodents. These findings implicated SOD1 in ALS pathogenesis and made the transgenic animals a widely used ALS model. However, previous studies of these animals have focused largely on motor neuron damage. We report herein that the spinal cords of mice expressing a human SOD1 mutant (hSOD1-G93A), besides showing typical destruction of motor neurons and axons, exhibit significant damage in the sensory system, including Wallerian-like degeneration in axons of dorsal root and dorsal funiculus, and mitochondrial damage in dorsal root ganglia neurons. Thus, hSOD1-G93A mutation causes both motor and sensory neuropathies, and as such the disease developed in the transgenic mice very closely resembles human ALS.

C-type natriuretic peptide attenuates renal osteodystrophy through inhibition of FGF-23/MAPK signaling

Dong Dong Zhang,Yang Fang Wu,Wei Xia Chen,Yao Xu,Si Yan Liu,Huang Huang Luo,Guang Mei Jiang,Yue Wu,Peng Hu 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

Renal osteodystrophy (ROD) occurs as early as chronic kidney disease (CKD) stage 2 and seems ubiquitous in almost all pediatric patients with CKD stage 5. Fibroblast growth factor (FGF)-23, a bone-derived endocrine regulator of phosphate homeostasis, is overexpressed in CKD and disturbs osteoblast differentiation and matrix mineralization. In contrast, C-type natriuretic peptide (CNP) acts as a potent positive regulator of bone growth. In the present study, we infused CNP into uremic rats and observed whether CNP could attenuate ROD through the inhibition of FGF-23 cascades. In uremic rats, CNP administration significantly alleviated renal dysfunction, calcium phosphate metabolic disorders, hypovitaminosis D, secondary hyperparathyroidism, the decrease in bone turnover markers and retarded bone pathological progression. More importantly, within FGF-23/mitogen-activated protein kinase (MAPK) signaling, the fibroblast growth factor receptor-1, Klotho and alternative (STAT-1/phospho-STAT-1) elements were upregulated by CNP, whereas FGF-23, RAF-1/phospho-RAF-1, and downstream (ERK/phospho-ERK and P38/phospho-P38) elements were paradoxically underexpressed in bone tissue. Therefore, CNP exerts a therapeutic effect on ROD through inhibition of FGF-23/MAPK signaling at the RAF-1 level.

Influence of Kluyveromyces marxianus on proteins, peptides, and amino acids in Lactobacillus-fermented milk

Dong-Dong Zhang,Jing-Lan Liu,Tie-Min Jiang,Lu Li,Guo-Zhen Fang,Yan-Pin Liu,Li-Jun Chen 한국식품과학회 2017 Food Science and Biotechnology Vol.26 No.3

With increasing application of yeast in fermented milk, in order to study the effect of yeast on milk protein during the fermentation process, the effects of the presence of Kluyveromyces marxianus in milk fermented by Streptococcus thermophilus and Lactobacillus bulgaricus were investigated. After fermentation, the amino acid, protein, and peptide contents were analyzed by ultra-performance liquid chromatography, two-dimensional gel electrophoresis, and liquid chromatography–mass spectrometry, respectively. After the addition of K. marxianus for fermentation, 25 protein spots changed significantly. These were mostly caseins and bovine serum proteins, and the content of total free amino acids increased by 16.30%; ten types of bioactive peptides were identified. Furthermore, the number of peptide types in milk fermented by K. marxianus increased significantly compared with milk fermented by Lactobacillus. K. marxianus is considered to promote proteometabolism in milk when added with Lactobacillus, generate flavor compounds, and improve the digestion and absorption character of milk.

Study of New Mode of Policy-making in Public Crises: Take PX Projects in China as an Example

( Dong Yan Chun ) 한국정책학회 2013 International Journal of Policy Studies Vol.4 No.1

At present public crisis incidents taken place frequently in China, which lead to large-scale group events and damage stability and development of the society. Through case studies on the PX events that happened in Xiamen, Dalian, Ningbo and Xianyang recently, we summed up the process of the Chinese-style public crises. The process contains five stages: project approval, construction, protest, work stoppages, and termination (relocation). Based on analysis of causes and harms of the Chinese-style public crises, we built a negotiated governance mode, which participated by the government, enterprises, residents and social groups, so as to seek a new path to solve the problem.

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.

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.