Post-fi re Behavior of Welded Hollow Spherical Joints Subjected to Eccentric Loads

Jie Lu,Hongbo Liu,Zhi-Hua Chen 한국강구조학회 2018 International Journal of Steel Structures Vol.18 No.2

Welded hollow spherical joints are widely used as a connection pattern in space lattice structures. Understanding the postfi re residual behavior of welded hollow spherical joints is crucial for fi re damage assessment of the space lattice structures. However, the post-fi re behavior of welded hollow spherical joints has not been explored in existing studies. In this paper, experimental and numerical studies were conducted to investigate the residual behavior of eccentrically loaded welded hollow spherical joints after fi re exposure. Eccentric compressive tests were performed on fi ve joint specimens after exposure to the ISO-834 standard fi re (including both heating and cooling phases), and three highest fi re temperatures, i.e., 600, 800, and 1000 °C, were considered. The temperature distributions in the specimens during the heating and cooling process and the related mechanical behavior of the specimens, such as load versus longitudinal displacement and rotation responses, load-bearing capacities, and strain distributions, were obtained and analyzed. Finite element analysis (FEA), including both heat transfer and mechanical analysis, were also developed using the ABAQUS software. Having validated the FE models against the experimental results, a design method was proposed on the basis of parametric studies to predict the residual load-bearing capacity of eccentrically loaded welded hollow spherical joints after fi re exposure.

Correlation of Adventitial Vasa Vasorum with Intracranial Atherosclerosis: A Postmortem Study

Lu Zheng,Wen Jie Yang,Chun Bo Niu,Hai Lu Zhao,Ka Sing Wong,Thomas Wai Hong Leung,Xiang Yan Chen 대한뇌졸중학회 2018 Journal of stroke Vol.20 No.3

Background and Purpose Vasa vasorum (VV) have been believed to be rare or non-existent in small-caliber intracranial arteries. In a series of human cerebral artery specimens, we identified and examined the distribution of VV in association with co-existing intracranial atherosclerosis. Methods We obtained cerebral artery specimens from 32 consecutive autopsies of subjects aged 45 years or above. We scrutinized middle cerebral artery (MCA), vertebral artery (VA), and basilar artery (BA) for the presence of adventitial VV. We described the distribution of VV, and the characteristics of co-existing atherosclerotic lesions. Results Among 157 intracranial arteries, adventitial VV were present in 74 of the 157 specimens (47%), involving MCA (n=13, 18%), BA (n=14, 19%), and VA (n=47, 64%). Although qualitatively these 74 adventitial VV distributed similarly in arteries with or without atherosclerotic lesions (disease-free arteries n=4/8; arteries of pre-atherosclerosis n=17/42; and arteries of progressive atherosclerosis n=53/107), the presence of adventitial VV in intracranial VA was associated with a heavier plaque load (1.72±1.66 mm2 vs. 0.40±0.32 mm2, P<0.001), severer luminal stenosis (25%±21% vs. 12%±9%, P=0.002), higher rate of concentric lesions (79% vs. 36%, P=0.002), and denser intraplaque calcification (44% vs. 0%, P=0.003). Histologically, intracranial VA with VV had a larger diameter (3.40±0.79 mm vs. 2.34±0.58 mm, P<0.001), thicker arterial wall (0.31±0.13 mm vs. 0.23±0.06 mm, P=0.002), and a larger intima-media (0.19±0.09 mm vs. 0.13± 0.04 mm, P=0.003) than VA without VV. Conclusions Our study demonstrated the distribution of adventitial VV within brain vasculature and association between vertebral VV and progressive atherosclerotic lesions with a heavier plaque load and denser intraplaque calcification.

Critical Factors Affecting Performance of Korean Small & Medium Firms Operating in China

Jie Lu,Ki-Hyun Kim 한국무역연구원 2010 무역연구 Vol.6 No.2

With a series of newly implemented laws and regulations, Chinese market is changing rapidly and has a profound impact on Korean small and medium firms’ performance operating in China. The withdrawal of Korean small and medium firms becomes a distinct phenomenon in the beginning of the year 2008 along with the changes of Chinese political and economic environment. The purpose of this paper is to examine the factors affecting the performance of Korean small and medium firms operating in China. Using a sample of 50 Korean small and medium firms located in China, this study finds out significant factors affecting the Korean small and medium firms’ performance. The multiple regression results find out important factors of R&D capacity, HR management, relationship with local government and marketing capability positively related to the performance of Korean small and medium firms operating in China. But the findings show that export ratio has no significant impacts on the performance.

RESEARCH ON THE RELATIONSHIP AMONG EWOM, CUSTOMER LOYALTY AND RESISTANT TO INNOVATION

Jie Lu ZheJiang,Yang Sun ZheJiang 글로벌지식마케팅경영학회 2020 Global Marketing Conference Vol.2020 No.11

Weight Loss Correlates with Macrophage Inhibitory Cytokine-1 Expression and Might Influence Outcome in Patients with Advanced Esophageal Squamous Cell Carcinoma

Lu, Zhi-Hao,Yang, Li,Yu, Jing-Wei,Lu, Ming,Li, Jian,Zhou, Jun,Wang, Xi-Cheng,Gong, Ji-Fang,Gao, Jing,Zhang, Xiao-Tian,Li, Jie,Li, Yan,Shen, Lin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.15

Background: Weight loss during chemotherapy has not been exclusively investigated. Macrophage inhibitory cytokine-1 (MIC-1) might play a role in its etiology. Here, we investigated the prognostic value of weight loss before chemotherapy and its relationship with MIC-1 concentration and its occurrence during chemotherapy in patients with advanced esophageal squamous cell carcinoma (ESCC). Materials and Methods: We analyzed 157 inoperable locally advanced or metastatic ESCC patients receiving first-line chemotherapy. Serum MIC-1 concentrations were assessed before chemotherapy. Patients were assigned into two groups according to their weight loss before or during chemotherapy:>5% weight loss group and ${\leq}5%$ weight loss group. Results: Patients with weight loss>5% before chemotherapy had shorter progression-free survival period (5.8 months vs. 8.7 months; p=0.027) and overall survival (10.8 months vs. 20.0 months; p=0.010). Patients with weight loss >5% during chemotherapy tended to have shorter progression-free survival (6.0 months vs. 8.1 months; p=0.062) and overall survival (8.6 months vs. 18.0 months; p=0.022), and if weight loss was reversed during chemotherapy, survival rates improved. Furthermore, serum MIC-1 concentration was closely related to weight loss before chemotherapy (p=0.001) Conclusions: Weight loss both before and during chemotherapy predicted poor outcome in advanced ESCC patients, and MIC-1 might be involved in the development of weight loss in such patients.

Resource Allocation and Offloading Decisions of D2D Collaborative UAV-assisted MEC Systems

Jie Lu,Wenjiang Feng,Dan Pu 한국인터넷정보학회 2024 KSII Transactions on Internet and Information Syst Vol.18 No.1

In this paper, we consider the resource allocation and offloading decisions of device-to-device (D2D) cooperative UAV-assisted mobile edge computing (MEC) system, where the device with task request is served by unmanned aerial vehicle (UAV) equipped with MEC server and D2D device with idle resources. On the one hand, to ensure the fairness of time-delay sensitive devices, when UAV computing resources are relatively sufficient, an optimization model is established to minimize the maximum delay of device computing tasks. The original non-convex objective problem is decomposed into two subproblems, and the suboptimal solution of the optimization problem is obtained by alternate iteration of two subproblems. On the other hand, when the device only needs to complete the task within a tolerable delay, we consider the offloading priorities of task to minimize UAV computing resources. Then we build the model of joint offloading decision and power allocation optimization. Through theoretical analysis based on KKT conditions, we elicit the relationship between the amount of computing task data and the optimal resource allocation. The simulation results show that the D2D cooperation scheme proposed in this paper is effective in reducing the completion delay of computing tasks and saving UAV computing resources.

Colonic Transit Disorder Mediated by Downregulation of Interstitial Cells of Cajal/Anoctamin-1 in Dextran Sodium Sulfate-induced Colitis Mice

Chen Lu,Hongli Lu,Xu Huang,Shaohua Liu,Jingyu Zang,Yujia Li,Jie Chen,Wenxie Xu 대한소화기 기능성질환∙운동학회 2019 Journal of Neurogastroenterology and Motility (JNM Vol.25 No.2

Background/Aims Interstitial cells of Cajal (ICC) and their special calcium-activated chloride channel, anoctamin-1 (ANO1) play pivotal roles in regulating colonic transit. This study is designed to investigate the role of ICC and the ANO1 channel in colonic transit disorder in dextran sodium sulfate (DSS)-treated colitis mice. Methods Colonic transit experiment, colonic migrating motor complexes (CMMCs), smooth muscle spontaneous contractile experiments, intracellular electrical recordings, western blotting analysis, and quantitative polymerase chain reaction were applied in this study. Results The mRNA and protein expressions of c-KIT and ANO1 channels were significantly decreased in the colons of DSS-colitis mice. The colonic artificial fecal-pellet transit experiment in vitro was significantly delayed in DSS-colitis mice. The CMMCs and smooth muscle spontaneous contractions were significantly decreased by 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB), an ANO1 channel blocker, and NG-Nitro-L-arginine methyl ester hydrochloride (L-NAME), an inhibitor of nitric oxide synthase activity, in DSS-colitis mice compared with that of control mice. Intracellular electrical recordings showed that the amplitude of NPPB-induced hyperpolarization was more positive in DSS-colitis mice. The electric field stimulation-elicited nitric-dependent slow inhibitory junctional potentials were also more positive in DSS-colitis mice than those of control mice. Conclusion The results suggest that colonic transit disorder is mediated via downregulation of the nitric oxide/ICC/ANO1 signalling pathway in DSS-colitis mice.

GIS적합성 평가에 따른 부산시 도시숲 입지 선정 연구

루지에치옹(Lu, Jie Qiong),김용석(Kim, Yong Suk),양건석(Yang, Geon Seok),이혜지(Lee, Hye Ji) 한국측량학회 2021 한국측량학회 학술대회자료집 Vol.2021 No.11

극한 기후 지수를 이용한 여름철 극한 고온 현상의 시공간적 변화특성에 관한 연구

루지에치옹(Jie-Qiong Lu),김용석(Yong-Suk Kim),양건석(Geon-Seok Yang) 한국콘텐츠학회 2023 한국콘텐츠학회논문지 Vol.23 No.7

전 세계적 극한 고온 현상의 잦은 출현으로 고온 기상 변화에 대한 관련 연구가 활발히 진행되고 있지만, 한국에서 장기간 축적된 기상자료를 이용한 시공간 분석에 대한 연구는 부족한 실정이다. 본 연구에서는 전국 59개 기상관측소의 40년간 일일 기상관측 자료를 바탕으로 6개의 극한고온 지수를 이용하여 여름철 극한 고온 현상의 시공간적 변화에 대한 연구를 수행하였다. Mann-Kendall 테스트는 시계열 자기 상관 관계에 의해 영향을 받을 수 있기 때문에 이 연구에서 변이점을 확인하기 위해 Sliding t 테스트를 추가로 사용하였으며, 그 결과 2005~2009년에는 상승 경향성이 급격히 변화하는 현상이 발생한 것을 알 수 있었다. 그리고 공간자기 상관에 대해 가장 일반적으로 사용되는 통계량 Morans I 지수를 이용하여 주로 고-고 밀집과 저-저밀집의 두 가지 공간밀집 형태이 나타났다. 추세변화 결과 공간분포 절대지수 SU와 TR의 변화율이 가장 빠르게 진행되었고, 전반적인 추세는 남서쪽에서 북동쪽으로 점차 감소하는 것으로 나타났다. With the frequent occurrence of extreme high temperature in the world, the research on high temperature weather changes is being actively carried out, but the research on temporal and spatial analysis using meteorological data accumulated in Korea for a long time is insufficient. In this study, based on 40 years of daily weather observation data from 59 weather stations across the Korea, a study was conducted on spatiotemporal changes in extreme high temperature phenomena in summer using six extreme high temperature indices. Since the Mann-Kendall test can be affected by time-series autocorrelation, the Sliding-t test was additionally used to confirm the variation point in this study, and as a result, it was found that the upward tendency changed rapidly from 2005 to 2009. And using the most commonly used statistic Morans I index for spatial autocorrelation, two types of spatial density were mainly found: high-high density and low-low density. As a result of the trend change, the rate of change in the spatial distribution absolute index SU and TR progressed the fastest, and the overall trend gradually decreased from the southwest to the northeast.

Association Between the Ku70-1310C/G Promoter Polymorphism and Cancer Risk: a Meta-analysis

Xu, Lu,Ju, Xiao-Bing,Li, Pu,Wang, Jue,Shi, Zhu-Mei,Zheng, Ming-Jie,Xue, Dan-Dan,Xu, Yan-Jie,Yin, Yong-Mei,Wang, Shui,You, Yong-Ping Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.2

Ku70 plays an important role in DNA double-strand break repair. Studies revealing conflicting results on the role of the Ku70-1310C/G promoter polymorphism on cancer risk led us to perform a meta-analysis to investigate this relationship. Ten case-control studies with 2566 cases and 3058 controls were identified. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of associations. The overall results suggested no association between the Ku70-1310C/G promoter polymorphism and total cancer risk. However, on stratified analysis, significantly increased risks were observed among the Asian population (GG vs. CC: OR=1.50, 95%CI=1.10-2.06; GG vs. CC/CG: OR=1.47, 95%CI=1.07-2.01) and population-based case-control studies (GG vs. CC: OR=1.57, 95%CI=1.12-2.22; CG vs. CC: OR=1.35, 95%CI=1.11-1.64; CG/GG vs. CC: OR=1.37, 95%CI=1.14-1.65). Additionally, variant genotypes were associated with a significantly increased breast cancer risk (GG vs. CC: OR=1.80, 95%CI=1.26-2.56; GG vs. CC/CG: OR=1.40, 95%CI=1.01-1.95).