An Improved Saliency Detection for Different Light Conditions

( Yongfeng Ren ),( Jingbo Zhou ),( Zhijian Wang ),( Yunyang Yan ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.3

In this paper, we propose a novel saliency detection framework based on illumination invariant features to improve the accuracy of the saliency detection under the different light conditions. The proposed algorithm is divided into three steps. First, we extract the illuminant invariant features to reduce the effect of the illumination based on the local sensitive histograms. Second, a preliminary saliency map is obtained in the CIE Lab color space. Last, we use the region growing method to fuse the illuminant invariant features and the preliminary saliency map into a new framework. In addition, we integrate the information of spatial distinctness since the saliency objects are usually compact. The experiments on the benchmark dataset show that the proposed saliency detection framework outperforms the state-of-the-art algorithms in terms of different illuminants in the images.

Ultrasensitive SERS-Based Immunoassay of Tumor Marker in Serum Using Au-Ag Alloy Nanoparticals and Ag/AgBr Hybrid Nanostructure

Yongfeng Gao,Yuanhui Feng,Lu Zhou,Lucia Petti,Zhe Wang,Jun Zhou,Shusen Xie,Jian Chen,Yanping Qing 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.1

Ultrasensitive detection of alpha-fetoprotein (AFP) is critical for the early diagnosis of liver cancer. In this work, a novel surface-enhanced Raman scattering (SERS)-based immunoassay complex has been successfully developed for the detection of AFP by using the Au-Ag alloy nanoparticals and the Ag/AgBr hybrid nanostructure. As the typical bimetal or metal/semiconductor plasmonic materials, besides the strong SERS enhancement characteristics, the Au-Ag alloy nanoparticals exhibit excellent monodispersity and the Ag/AgBr hybrid nanostructure demonstrates good stability. The experimental results show that the SERS-based immunoassay of AFP presents a low limit of detection of 1.86 fg/mL and a broad dynamic range from 2 fg/mL to 0.8 g/mL. Furthermore, the clinical applicability of the proposed SERS-based immunoassay has been assessed by the detection of AFP in the human serum samples of cancer patient and healthy person. The test data are consistent well with that of chemiluminescence immunoassay (CLIA) in the relative errors of –8.82–8.06% and show better detection sensitivity. It reveals that the proposed immunoassay protocol is significant for giving insight into the design of ultrasensitive biosensor and the point-of-care testing of cancers.

Is National Culture an Appropriate Unit of Analysis in Cross-Cultural Research?

Yongfeng Zhang(장영봉),Jongwook Kwon(권종욱),Yan Zhou(주암),Peng Wang(왕붕) 연세대학교 경영연구소 2021 연세경영연구 Vol.58 No.3

본 연구는 다문화 연구 분야에서 논란이 되고 있는 구체적인 연구문제를 해결하는 것이 목적이다. 다문화 연구에 있어서 연구의 분석단위가 국가인지 아니면 한 국가내의 지역인지가 논쟁이 되고 있다. 수십 년 동안 다양한 분야의 연구자들이 이러한 이론적 논쟁에 매달려 오고 있다. 본 연구는 Minkov and Hofstede(2012)의 연구 방법과 세계 가치 조사(World Values Survey)의 최신 데이터를 활용하여 비교문화 연구에서 분석의 단위가 국가가 바람직한지 아니면 지역단위가 바람직한지를 검증해 보고자 한다. 이를 위해 슈와르츠 가치관 값을 활용하여 5개 그룹, 19개국 239개 지역의 문화적 가치 차이를 분석한다. 5개 그룹은 아시아, 라틴 아메리카, 동유럽, 아랍 세계, 그리고 영국이 포함된다. 분석결과 국가간 문화차이보다 국가 내 문화적 차이가 큰 경우도 있고(중국·페루·러시아 등) 작은 경우(미국·요르단 등)도 발견되었다. 하지만 전체적으로 국가간 차이보다 지역간 차이가 작아서 비교문화 연구에서 연구의 분석단위는 한 국가 내 지역보다는 국가단위가 바람직한 것으로 나타났다. 또한 시간이 지날수록 국가 클러스터가 모이는 패턴이 달라진다는 사실도 발견했다. 본 연구는 비교문화 연구에서 논쟁이 되고 있는 국가 및 지역 단위의 분석단위 적합성에 대한 이론적 기반을 제공하고 다국적 기업들 간의 시장 전략 수립에 유용할 정보를 제공한다. The purpose of this paper is to address a specific controversial issue in the cross-cultural field: in cross-cultural studies, regarding whether the country or the region should be used as the unit of analysis. Cross-cultural similarities and differences play an important role in many areas of life. Researchers from various fields have been actively dealing with this topic for decades. Based on the research methods of Minkov and Hofstede (2012), and using the latest data from the World Values Survey, based on the Schwartz values, this study analyzes the differences in cultural values among 239 regions of 19 countries taken from five groups: Asia, Latin America, Eastern Europe, the Arab World, and Anglo countries. By analyzing the aggregation of homogeneous and heterogeneous clusters, this paper examines the judgment basis for and use of analytical units in cross-cultural research. The results show that cultural differences within some countries can be larger (e.g, China, Peru, Russia, etc.) or smaller (e.g, United States, Jordan, etc.) than differences among countries. We have also found a pattern of national cluster aggregation will be changed over time. This research provides a reference basis for effectively distinguishing the types of differences in national and regional values and provides theoretical information that will be useful in the formulation of market strategies among multinational companies.

Expression of Neurotrophin 4 and Its Receptor Tyrosine Kinase B in Reproductive Tissues during the Follicular and Luteal Phases in Cows

Sun, Yongfeng,Li, Chunjin,Sun, Yanling,Chen, Lu,Liu, Zhuo,Ma, Yonghe,Wang, Chunqiang,Zhang, Wei,Zhou, Xu Asian Australasian Association of Animal Productio 2011 Animal Bioscience Vol.24 No.3

The neurotrophins, required for the survival and differentiation of the nervous system, are known to be important for the development of the reproductive tissues. However, the signals initiating the growth of follicles, gamete development, and transport and the development of zygote in the reproductive system of cows remain ambiguous. The purpose of the present study was to identify the transcripts and proteins of Neurotrophin 4 (NT4) and its receptor tyrosine kinase B (TrkB) in bovine reproductive tissues. The transcripts and immunoreactivity of NT4 and TrkB proteins were detected by reverse transcription polymerase chain reaction and western blot analysis. Using immunohistochemistry, the specific immunoreactivity of NT4 and TrkB were detected in the oocytes of primordial follicles and in the growing primary follicles. The NT4 and TrkB immunoreactivity was predominantly observed in granulosa cells, cumulus granulosa cells, cumulus oocyte complexes, theca cells of mature follicles, as well as in the oviduct epithelial cells, uterine gland cell, and epithelium cells of the uterus during the follicular and luteal phases in cows. Expressions of NT4 and TrkB mRNAs were not significantly different among the ovary, oviduct, and uterus of the follicular phase. For the luteal phase, the expression of NT4 mRNA in the ovary was significantly higher than that in the oviduct and uterus, and the expression of TrkB mRNA in the oviduct was significantly higher than that in the ovary and uterus, as determined by fluorescence quantitative reverse transcription polymerase chain reaction. The expression of NT4 mRNA was significantly higher than that of TrkB mRNA in the ovary and uterus, whereas NT4 mRNA expression was lower than that of TrkB mRNA in the oviduct during the luteal phase. The present study hypothesizes that NT4 participates in the regulation of both gonads and extra-gonadal reproductive tissues in cows.

Practical Residual Force Decomposition Method for Damage Identifi cation of Existing Reticulated Shells

Jun Wu,Yongfeng Luo,Lei Wang 한국강구조학회 2019 International Journal of Steel Structures Vol.19 No.6

The non-destructive damage identifi cation approaches for existing structures become more of a concern due to safety requirements. However, the application of damage identifi cation method is still limited for complex spatial structures. In this paper, a practical residual force decomposition (RFD) method is proposed to identify damaged members in existing reticulated shell structures. A parameterized model is built by taking the stiff ness reduction into consideration. In the proposed RFD method, the signifi cant damage can be recognized corresponding to the changes of the observed eigenvector of the reticulated shells, and the eigenvector changes can be easily transferred to a set of multivariate linear equations to locate the members with signifi cant stiff ness reduction. The inputs of the equations are discussed including the additional constraints and the selection of eff ective modes. According to the diff erent proportion of the numbers of members and joints, three situations of the solution are discussed. Especially when the solution is not unique, the importance coeffi cients of structural members are introduced as additional constraints through Ritz vector sensitivity analysis and application of the Modal Assurance Criterion. Two illustrative examples including a single-layer Kiewitt-6 reticulated shell and a structural model of international convention center are adopted to demonstrate the eff ectiveness of the approach. The results show that the proposed method can yield a suitable damage identifi cation.

Salient Object Detection via Multiple Random Walks

( Jiyou Zhai ),( Jingbo Zhou ),( Yongfeng Ren ),( Zhijian Wang ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.4

In this paper, we propose a novel saliency detection framework via multiple random walks (MRW) which simulate multiple agents on a graph simultaneously. In the MRW system, two agents, which represent the seeds of background and foreground, traverse the graph according to a transition matrix, and interact with each other to achieve a state of equilibrium. The proposed algorithm is divided into three steps. First, an initial segmentation is performed to partition an input image into homogeneous regions (i.e., superpixels) for saliency computation. Based on the regions of image, we construct a graph that the nodes correspond to the superpixels in the image, and the edges between neighboring nodes represent the similarities of the corresponding superpixels. Second, to generate the seeds of background, we first filter out one of the four boundaries that most unlikely belong to the background. The superpixels on each of the three remaining sides of the image will be labeled as the seeds of background. To generate the seeds of foreground, we utilize the center prior that foreground objects tend to appear near the image center. In last step, the seeds of foreground and background are treated as two different agents in multiple random walkers to complete the process of salient object detection. Experimental results on three benchmark databases demonstrate the proposed method performs well when it against the state-of-the-art methods in terms of accuracy and robustness.

Geometric Imperfection Distributions of Existing Reticulated Shells: Theoretical and Experimental Analysis

Wu Jun,Luo Yongfeng,Wang Lei 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.5

Geometric imperfection is one of the most disadvantageous factors that impair mechanical behaviors of existing reticulated shell structures. However, the available consistent mode methods and statistical methods which usually applied in designing structures can hardly estimate the actual geometric imperfection distribution for existing structures, because these methods use the assumed imperfections. In this paper, a Markov Random Field (MRF) theoretical model of existing reticulated shells is established by introducing the theory of probabilistic graphical model. The unit of graphic model named node clique are proposed to deduct the geometric state function of reticulated shells, based on the local Markov property. Then the inversion function along with its iterative equation is established to predict geometric imperfection distribution of existing reticulated shells. The MRF method makes the predicted distribution of the numerical model as consistent as possible with its corresponding actual structure, and only a few measurement nodes are needed as known conditions. An experimental structure of K6 single-layer reticulated shell is built to verify the proposed theory by comparing the calculated geometric imperfection distribution results with the actual measured data. Meanwhile, the signifi cance level of the calculated results between MRF and traditional stochastic method is analyzed, which shows MRF method can eff ectively predict the geometric imperfections of single layer reticulated shells.

Mechanism of stress-whitening in semicrystalline polymers

Ying Lu,Yaotao Wang,Yongfeng Men 한국고분자학회 2016 한국고분자학회 학술대회 연구논문 초록집 Vol.41 No.2

Investigation of Electrochemical Performance on SnSe2 and SnSe Nanocrystals as Anodes for Lithium Ions Batteries

Yayi Cheng,Jianfeng Huang,Liyun Cao,Yongfeng Wang,Ying Ma,Shaohua Xi,Bingyao Shi,Hui Xie,Jiayin Li 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.15 No.01

SnSe2 and SnSe nanocrystals were prepared using a simple solvothermal method by changing the molar ratio of SnCl2 · 2H2O and Se powder. When SnSe2 and SnSe are acted as lithium ion battery anodes, the SnSe hybrid structure shows more excellent electrochemical performance than that of SnSe2 interconnected nanosheet. It delivers a reversible capacity of 1023 mA h g -1 at a current density of 200 mA g -1, and maintaining a capacity of 498 mA h g -1 till 120 cycles. According to many present works, SnSe2 with interconnected thin nanosheet should possess more superior property than hybrid structured SnSe due to short charge transfer paths. However, in our research, the result is the opposite. Therefore, we consider that the superior electrochemical performance of SnSe is attributed to its highly reversible conversion reaction mechanism than SnSe2.

Dissecting the meteorological and genetic factors affecting rice grain quality in Northeast China

Chen Mojun,Li Zhao,Huang Jie,Yan Yongfeng,Wu Tao,Bian Mingdi,Zhou Jinsong,Wang Yongjun,Lyv Yanjie,Hu Guanghui,Jin Yong-Mei,Huang Kai,Guo Liping,Jiang Wenzhu,Du Xinglin 한국유전학회 2021 Genes & Genomics Vol.43 No.8

Background The Northeast Plain of China, which is an important region for the production of high grain quality rice in China. However, the grain quality of the rice produced varies across this region, even for the same cultivar. Objective In order to explore the meteorological factors that have the greatest infuence on quality and the transcriptional level diferences between diferent cultivars and diferent locations at grain flling stage. Methods We grew eight rice cultivars in three locations in Northeast China during two growing seasons (2017 and 2018). We recorded meteorological conditions, including air temperature, air temperature range, and photosynthetically active radiation (PAR) during the grain-flling stage of each cultivar, and analyzed the grain quality of those eight cultivars. Results Across all eight cultivars, meteorological factors had a stronger efect on eating quality than genotype, while genotype had a stronger efect on milling quality. Of the three environmental factors assessed, PAR was signifcantly correlated with the most grain quality traits. Using RNA-sequencing analysis, we identifed 573 environment-specifc DEGs (Diferentially Expressed Genes), and 119 genotype-specifc DEGs; 11 DEGs were responsive to genotype×environment interactions. These DEGs were involved in many key metabolic processes. Conclusion Our results indicated that interactions among environmental factors, especially PAR, afected rice quality in Northeast China. Further analyses of the DEGs identifed herein may provide useful information for future breeding programs aiming to develop high grain quality rice varieties suitable for cultivation across Northeast China.