• Title/Summary/Keyword: Laboratory class

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Education Effect of a Web-based Virtual Laboratory for Digital Logic Circuits (웹기반 디지털 논리회로 가상실험실의 교육효과)

  • Lee, Sun-heum;Choi, Kwan-Sun;Kim, Dong-Sik;Kim, Wonkyum
    • The Journal of Korean Association of Computer Education
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    • v.11 no.1
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    • pp.23-32
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    • 2008
  • In this paper, we have investigated the education effect of a web-based virtual laboratory for digital logic circuits which consists of multimedia contents about the usages of equipments for logic circuit experiments and the experimental logic circuits. In case of the engineering experiment of the lower grades in universities, preunderstanding about the usages of experimental equipments and the experimental circuits is necessary for the learners to conduct the experiments well. But it is impossible for the learners to have access to the real experimental equipments earlier due to the lack of equipments and the difficulty in management of the equipments. We have implemented the digital logic circuit virtual laboratory which provides the same experimental environment as a real experimental lab, and the learner can conduct the same experiments as the real ones before the real laboratory class. The learners using the laboratory have reduced the experiment completion time by the average of about 8.2% during a term, compared with the learners not using the lab.

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Thermal Vacuum Test and Thermal Analysis for a Qualification Model of Cube-satellite STEP Cube Lab. (큐브위성 STEP Cube Lab.의 임무 탑재체 인증모델의 열진공시험 및 열모델 보정을 통한 궤도 열해석)

  • Kang, Soo-Jin;Ha, Heon-Woo;Han, Sung-Hyun;Seo, Joung-Ki;Oh, Hyun-Ung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.44 no.2
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    • pp.156-164
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    • 2016
  • Qualification model(QM) of main payloads including concentrating photovoltaic system using fresnel lens, heating wire cutting type shockless holding and release mechanism, and MEMS-based solid propellant thruster have been developed for the STEP Cube Lab.(Cube Laboratory for Space Technology Experimental Project), which is a pico-class satellite for verification of core space technologies. In this study, we have verified structural safety and functionality of the developed payloads under a qualification temperature range through the QM thermal vacuum test. Additionally, a reliability of thermal model of the payloads has been confirmed by performing a thermal correlation based on the thermal balance test results.

A Longitudinal Study on the Prevalence of Major Adult Chronic Disease in Korean Employees between 2001 and 2010

  • Lee, Gyu-Jang;Kim, Soon-Ki;Kim, Hye-Young;Lee, Chang-Kyou;Lee, Seung-Gwan;Cho, Kyung-Jin
    • Korean Journal of Clinical Laboratory Science
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    • v.44 no.1
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    • pp.7-16
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    • 2012
  • The Korean GDP per capita doubled during the last 10 years. As the GDP increases, Korean health behaviors such as, eating, drinking, smoking, and exercise habits changed as well. Compared to the remarkably advanced diagnostic technologies and therapeutics during the last decade, the leading causes of death in Korea scarcely changed. Among the leading causes of death, cerebrovascular disease, heart disease, diabetes, liver disease and hypertension are closely related to health behaviors. Using the database of medical check-up between 2001 and 2010, the authors performed a longitudinal study for the prevalence rates and the trends of major chronic adult diseases among the 2,721 workers along with their health behavior. Among the diagnostic test items, fasting blood sugar, cholesterol and BMI levels showed steady increase and these three test items all showed linear trends (p<0.001). The average blood sugar and cholesterol levels were near worrying levels. Moreover, the average BMI of males was found to be at the overweight level, intimating the possibility reaching thee Obese Class I level soon if there are no aggressive counter measures. Fasting blood sugar and cholesterol levels were higher in a drinking group as compared to a non-drinking group, and the BMI levels were also higher in the drinking group and the smoking group as compared to the non-drinking and the non-smoking group (p<0.001). Finally, the authors believe that the fasting blood sugar, cholesterol and BMI levels should be designated as target monitoring test items in the medical check-up for Korean employees.

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Regulation Roles of MICA and NKG2D in Human Renal Cancer Cells

  • Jia, Hong-Ying;Liu, Jun-Li;Yuan, Ming-Zhen;Zhou, Cheng-Jun;Sun, Wen-Dong;Zhao, Jing-Jie;Wang, Jue;Liu, Ling;Luan, Yun
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.9
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    • pp.3901-3905
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    • 2015
  • Objective: Our aim was to investigation the roles of MHC class I chain-related gene A(MICA) and natural killer cell group 2D(NKG2D) in human renal cancer cells. Materials and Methods: The expression of membrane MICA (mMICA) on renal cells and NKG2D on NK cells were detected by flow cytometry (FCM); the content of sMICA were detected by enzyme linked immunosorbent assay (ELISA) and the distribution of mMICA on renal tumor tissues by immunohistochemistry; the interaction between MICA and NKG2D was observed by antibody closed method. Results: Our results showed that the expression of mMICA in renal cancer tissues was significantly higher than in controls, where the soluble MICA was not expressed. Cytotoxic activity of NK cells was significantly reduced after exposure to NKG2D and MICA antibodies (P<0.05), and serum containing sMICA can obviously lower the function of NKG2D (P<0.05). Conclusions: The interaction of mMICA and NKG2D play important roles in mediation of cytotoxicity of NK cells in RCC. On the other hand, sMICA may mediate tumor immune escape through down- regulated NKG2D expression.

High Expression of MICA in Human Kidney Cancer Tissue and Renal Cell Carcinoma Lines

  • Jia, Hong-Ying;Liu, Jun-Li;Zhou, Cheng-Jun;Kong, Feng;Yuan, Ming-Zhen;Sun, Wen-Dong;Wang, Jue;Liu, Ling;Zhao, Jing-Jie;Luan, Yun
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.4
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    • pp.1715-1717
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    • 2014
  • The overall incidence and mortality of renal cell carcinoma (RCC), the most common kidney cancer, are steadily increasing for reasons that are not fully explained. Our aim was to explore the expression of membrane MHC class I chain-related gene A (mMICA) in human RCC cell lines and tissue specimens, and to determine expression of soluble MICA (sMICA) in serum of patients with renal cell carcinoma, we used flow cytometry (FCM) and immunohistochemistry as well as an enzyme linked immunosorbent assay (ELISA). The results showed that percentage of mMICA expression was significantly increased in human kidney cancer tissues and RCC cell lines (786-O and Ketr-3) than that in healthy adults and human embryonic kidney 293 (HEK293) cell line individuality (P<0.05). sMICA content in healthy adults was negative, but in renal cancer patients was significantly elevated (P<0.05). Our research showed that high expression of MICA in human kidney cancer, this results show that MICA might serve as potential tumor-associated antigen (TAA) in RCC.

Research on a handwritten character recognition algorithm based on an extended nonlinear kernel residual network

  • Rao, Zheheng;Zeng, Chunyan;Wu, Minghu;Wang, Zhifeng;Zhao, Nan;Liu, Min;Wan, Xiangkui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.1
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    • pp.413-435
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    • 2018
  • Although the accuracy of handwritten character recognition based on deep networks has been shown to be superior to that of the traditional method, the use of an overly deep network significantly increases time consumption during parameter training. For this reason, this paper took the training time and recognition accuracy into consideration and proposed a novel handwritten character recognition algorithm with newly designed network structure, which is based on an extended nonlinear kernel residual network. This network is a non-extremely deep network, and its main design is as follows:(1) Design of an unsupervised apriori algorithm for intra-class clustering, making the subsequent network training more pertinent; (2) presentation of an intermediate convolution model with a pre-processed width level of 2;(3) presentation of a composite residual structure that designs a multi-level quick link; and (4) addition of a Dropout layer after the parameter optimization. The algorithm shows superior results on MNIST and SVHN dataset, which are two character benchmark recognition datasets, and achieves better recognition accuracy and higher recognition efficiency than other deep structures with the same number of layers.

Resistance Function of Rice Lipid Transfer Protein LTP110

  • Ge, Xiaochun;Chen, Jichao;Li, Ning;Lin, Yi;Sun, Chongrong;Cao, Kaiming
    • BMB Reports
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    • v.36 no.6
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    • pp.603-607
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    • 2003
  • Abstract Plant lipid transfer proteins (LTPs) are a class of proteins whose functions are still unknown. Some are proposed to have antimicrobial activities. To understand whether LTP110, a rice LTP that we previously identified from rice leaves, plays a role in the protection function against some serious rice pathogens, we investigated the antifungal and antibacterial properties of LTP110. A cDNA sequence, encoding the mature peptide of LTP110, was cloned into the Impact-CN prokaryotic expression system. The purified protein was used for an in vitro inhibition test against rice pathogens, Pyricularia oryzae and Xanthomonas oryzae. The results showed that LTP110 inhibited the germination of Pyricularia oryzae spores, and its inhibitory activity decreased in the presence of a divalent cation. This suggests that the antifungal activity is affected by ions in the media; LTP110 only slightly inhibited the growth of Xanthomonas oryzae. However, the addition of LTP110 to cultured Chinese hamster ovarian cells did not retard growth, suggesting that the toxicity of LTP110 is only restricted to some cell types. Its antimicrobial activity is potentially due to interactions between LTP and microbe-specific structures.

Implementation of a Web-based Virtual Laboratory System for Digital Logic Circuits Using Virtual Digital Kit (가상 디지털 키트를 이용한 웹기반 논리회로 가상실험시스템의 구현)

  • Kim, Dongsik;Moon, Ilhyun;Woo, Sangyeon
    • The Journal of Korean Association of Computer Education
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    • v.10 no.6
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    • pp.11-18
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    • 2007
  • The proposed virtual laboratory system for digital logic circuits is composed of two main sessions, which are concept-learning session and virtual experiment session by virtual digital kit. During concept-learning session the learners can easily understand the important principles in the digital circuits to be performed. In addition, during virtual laboratory session the virtual experiments are performed by assembling and connecting the circuits on the virtual bread board, applying input voltages, making the output measurements, and comparing and transmitting the virtual experimental data. Every activity done during the virtual laboratory session is recorded on database and will be provided with the learners as a preliminary report form including personal information. Thus, the educators may check out the submitted preliminary report to estimate how well the learners understand the circuit operations. Finally, in order to show the validity of our virtual laboratory system we investigated and analysed the damage rate of real experimental equipment during class and assessed student performance on the five quizzes for one semester.

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Advances in the chemistry, pharmacological diversity, and metabolism of 20(R)-ginseng saponins

  • Wang, Chaoming;Liu, Juan;Deng, Jianqiang;Wang, Jiazhen;Weng, Weizhao;Chu, Hongxia;Meng, Qingguo
    • Journal of Ginseng Research
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    • v.44 no.1
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    • pp.14-23
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    • 2020
  • Ginseng has been used as a popular herbal medicine in East Asia for at least two millennia. However, 20(R)-ginseng saponins, one class of important rare ginsenosides, are rare in natural products. 20(R)-ginseng saponins are generally prepared by chemical epimerization and microbial transformation from 20(S)-isomers. The C20 configuration of 20(R)-ginseng saponins are usually determined by 13C NMR and X-ray single-crystal diffraction. 20(R)-ginseng saponins have antitumor, antioxidative, antifatigue, neuroprotective, and osteoclastogenesis inhibitory effects, among others. Owing to the chemical structure and pharmacological and stereoselective properties, 20(R)-ginseng saponins have attracted a great deal of attention in recent years. In this study, the discovery, identification, chemical epimerization, microbial transformation, pharmacological activities, and metabolism of 20(R)-ginseng saponins are summarized.

Load Balancing in Cloud Computing Using Meta-Heuristic Algorithm

  • Fahim, Youssef;Rahhali, Hamza;Hanine, Mohamed;Benlahmar, El-Habib;Labriji, El-Houssine;Hanoune, Mostafa;Eddaoui, Ahmed
    • Journal of Information Processing Systems
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    • v.14 no.3
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    • pp.569-589
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    • 2018
  • Cloud computing, also known as "country as you go", is used to turn any computer into a dematerialized architecture in which users can access different services. In addition to the daily evolution of stakeholders' number and beneficiaries, the imbalance between the virtual machines of data centers in a cloud environment impacts the performance as it decreases the hardware resources and the software's profitability. Our axis of research is the load balancing between a data center's virtual machines. It is used for reducing the degree of load imbalance between those machines in order to solve the problems caused by this technological evolution and ensure a greater quality of service. Our article focuses on two main phases: the pre-classification of tasks, according to the requested resources; and the classification of tasks into levels ('odd levels' or 'even levels') in ascending order based on the meta-heuristic "Bat-algorithm". The task allocation is based on levels provided by the bat-algorithm and through our mathematical functions, and we will divide our system into a number of virtual machines with nearly equal performance. Otherwise, we suggest different classes of virtual machines, but the condition is that each class should contain machines with similar characteristics compared to the existing binary search scheme.