An Adaptive Orthogonal M-Split Initialization Method for VQ Codebook Generation

Weijun He,Qianhua He,Jichen Yang 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.8

Linde–Buzo–Gray (LBG) algorithm is a universal method to design codebook in vector quantization(VQ). This paper proposed an adaptive orthogonal M-split initialization method to improve the computational efficiency of LBG algorithm. The method splits one code word into 2, 4 or 5 new code words with adaptive split coefficient vectors and set the increment to be orthogonal in 4-split and 5-split situations, aiming at decreasing the iterations of the following clustering. Experiment is conducted on both TIMIT and RASC863 speech database, which shows that the proposed algorithm provides a reduction of 18%~45% in designing codebook in size of 64~2048 with almost equal VQ performance, compared with the universal codebook generation algorithm.

Mineralogical and geochemical study of hydrothermal dolomite from the Daliang zinc deposit in Guizhou, Southwest China: new evidence for the genesis

Weijun He,Youguo Li,Sigen Ma 한국지질과학협의회 2023 Geosciences Journal Vol.27 No.2

The Daliang zinc deposit occurs in the southwestern Xiangxi–Qiandong Zn-Pb metallogenic belt and is located on the southeastern margin of the upper Yangtze block. In this study, we present results from petrographic observations, rare earth elements, C-H-O isotopes, and fluid inclusions. The zinc deposit is hosted by middle Cambrian dolomite. The ore-forming process is divided into three stages from early to late: pyrite-galena, sphalerite-pyrite-dolomite, and dolomite. The characteristics of the REEs suggest that multiple fluids were involved in hydrothermal dolomite precipitation under low-temperature conditions. Two types of hydrothermal dolomite fluid inclusions were identified: pure liquid phase inclusions and liquid-rich phase inclusions. The fluid inclusions of hydrothermal dolomite yield homogenization temperatures of 108–192℃ (average 153℃), with salinities of 12.3–26.4 wt% (average 23.0 wt%) NaCl equiv. The δ13Cfluid, δDfluid and δ18Ofluid values for ore-forming fluids range from −4.2 to −3.5‰ (mean −3.8‰), −38.8 to −34.3‰ (mean −36.0‰), and 6.2–6.4‰ (mean 6.3‰), respectively. This study demonstrates that ore-forming fluid was sourced from a moderate- to high-salinity basinal brine and leached metals from metasedimentary rocks of the basement in the Yangtze block. The main transportation of ore-forming fluid occurred in the form of chlorine complexes along well-developed faults, and sulfides precipitated with decreases in pressure and temperature, as well as pH changes. Studies of the Daliang zinc deposit suggest that it is a mediumto low-temperature MVT-like deposit.

In Situ Synthesis and Strengthening of Powder Metallurgy High Speed Steel in Addition of LaB6

Weijun Shen,Linping Yu,Zhi Li,Yuehui He,Qiankun Zhang,Huibin Zhang,Yao Jiang,Nan Lin 대한금속·재료학회 2017 METALS AND MATERIALS International Vol.23 No.6

A novel technology which was characterized by the vacuum solid state sintering was developed for powder metallurgyhigh speed steels production. During sintering, both the WC and Mo2C reacted with Fe and transformed toW and Mo rich M6C carbides which were the common hard phases in high speed steels. Also, a high number of W,Mo and Fe were dissolved in VC, forming the MC carbides. The densification of the material mainly relied on thesolubility effect during the M6C and MC carbides formation. By alloying with a 0.1 wt% of LaB6 to the steel, thebending strength and the fracture toughness were improved from 3290 MPa and 25.6 MPam1/2to 4018 MPa and29.4 MPam1/2, respectively. The TEM analysis demonstrated three types of reaction products by the LaB6 addition:the amorphous phase, the core-shell structure and the La2O3 phase. The impurity elements such as the Mg, Al,Si, S, Ca, and O were absorbed following the LaB6 addition. Moreover, the deoxidization effect caused by the LaB6addition promoted the sintering at a high-temperature period which contributed to the bending strength and fracturetoughness improvement.

The path analysis of carbon emission reduction: A case study of the Silk Road Economic Belt

Yang Kong,Weijun He 대한환경공학회 2020 Environmental Engineering Research Vol.25 No.1

This paper uses super-efficiency DEA model and Malmquist index to evaluate the carbon emission efficiency (CEE) values of the nine western provinces along the “Silk Road Economic Belt” for the period from 2000 to 2015, and analyses the influencing factors of the CEE. The major findings of this study are the following: (1) the overall CEE of the nine western provinces is not high, and there are significant inter-provincial differences in the CEE. Meanwhile, the provinces with higher levels of economic development generally have higher CEE. (2) The annual total factor productivity (TFP) of the nine western provinces, which is mainly determined by technological change, is greater than 1. Moreover, the total average growth rate of the TFP is 15.5%. (3) The CEE of the nine western provinces is not spatially dependent. In addition, the urbanization, openness, use of energy-saving technologies and research and development (R&D) investment have a significant positive impact on the CEE values, while the industrial structure, foreign direct investment, fixed asset investment, government expenditure levels and energy structure have a significant negative impact on the CEE. Among them, R&D investment is the primary factor in promoting the development of CEE, and the government expenditure has the greatest negative impact on the CEE.

Two-stage concession game approach for analyzing greenhouse gases emission reduction schemes

Liang Yuan,Weijun He,Dagmawi Mulugeta Degefu,Kim Soonja,Shen Juqin,An Min 대한환경공학회 2016 Environmental Engineering Research Vol.21 No.4

Climate change imposes a huge treat on the sustainability of our environment. One of the major reasons for the increasing impacts of climate change is the emission of greenhouse gases. Therefore, cooperative greenhouse gas emission reduction schemes with a general consensus are needed in order to reduce the impacts of climate change. Due to the strong link between greenhouse gas emission and economic development there is disagreement among countries on the designing and implementation of emission reduction plans. In this paper the authors proposed a two-stage concession game to analyze emission reduction plans and determine a balanced emission range that improves the utilities of the bargaining parties. Furthermore the game was applied to a hypothetical example. Our results from the case study indicated that even though the utilities of the bargaining parties is highly affected by emission reductions, after making concessions their utilities can be improved given their emission reductions are within in a certain desirable range. The authors hope that this article provides insights which could be useful for understanding emission reduction plans and their consequences on the negotiating parties.

Biexponential Apparent Diffusion Coefficients Values in the Prostate: Comparison among Normal Tissue, Prostate Cancer, Benign Prostatic Hyperplasia and Prostatitis

Xiaohang Liu,Weijun Peng,Liangping Zhou,He Wang 대한영상의학회 2013 Korean Journal of Radiology Vol.14 No.2

Objective: To investigate the biexponential apparent diffusion parameters of diverse prostate tissues and compare them with monoexponential apparent diffusion coefficient (ADC) value in the efficacy to discriminate prostate cancer from benign lesions. Materials and Methods: Eleven healthy volunteers and 61 patients underwent a conventional (b-factors 0, 1000 s/mm2) and a 10 b-factor (0 to 3000 s/mm2) diffusion-weighted imaging (DWI). The monoexponential ADC value and biexponential parameters of fast ADC (ADCf), fraction of ADCf (f), slow ADC (ADCs) value for 29 prostate cancer, 28 benign prostatic hyperplasia (BPH), 24 prostatitis lesions and normal tissue were calculated and compared. Receiver operating characteristic analysis was performed to determine the sensitivity, specificity and optimal cut-off points. Results: Prostate cancer had lower ADC, ADCf, f, and ADCs than all other tissues (p < 0.01). Prostatitis exhibited a lower ADC, ADCf, ADCs and f than the peripheral zone tissue (p < 0.01), and BPH showed a lower ADC and ADCf than the central gland tissue (p < 0.01). The ADCf demonstrated a comparable accuracy with ADC in differentiating cancer from BPH [area under the curve (AUC) 0.93 vs. 0.92] and prostatitis AUC 0.98 vs. 0.99) (both p > 0.05), but the AUC of f and ADCs in differentiating cancer from BPH (0.73 and 0.81) and prostatitis (0.88 and 0.91) were significantly lower than ADC (all p < 0.05). Conclusion: The biexponential DWI appears to provide additional parameters for tissue characterization in prostate, and ADCf helps to yield comparable accuracy with ADC in differentiating cancer from benign lesions.

Evaluation of Salivary Gland Function Using Diffusion-Weighted Magnetic Resonance Imaging for Follow-Up of Radiation-Induced Xerostomia

Yunyan Zhang,Dan Ou,Yajia Gu,Xiayun He,Weijun Peng 대한영상의학회 2018 Korean Journal of Radiology Vol.19 No.4

Objective: To investigate the value of diffusion-weighted magnetic resonance imaging (DW-MRI) as a noninvasive tool to assess salivary gland function for follow-up of patients with radiation-induced xerostomia. Materials and Methods: This study included 23 patients with nasopharyngeal carcinoma who had been treated with parotidsparing radiotherapy (RT). Salivary function was assessed by DW-MRI pre-treatment and one week and one year post-RT, respectively. The maximum apparent diffusion coefficient (ADC) of parotid glands (pADCmax) and the time to peak ADC of parotid glands (pTmax) during stimulation were obtained. Multivariate analysis was used to analyze factors correlated with the severity of radiation-induced xerostomia. Results: The ADCs of parotid and submandibular glands (1.26 ± 0.10 x 10-3 mm2/s and 1.32 ± 0.07 x 10-3 mm2/s pre-RT, respectively) both showed an increase in all patients at one week post-RT (1.75 ± 0.16 x 10-3 mm2/s, p < 0.001 and 1.70 ± 0.16 x 10-3 mm2/s, p < 0.001, respectively), followed by a decrease in parotid glands at one year post-RT(1.57 ± 0.15 x 10-3 mm2/s, p < 0.001) but not in submandibular glands (1.69 ± 0.18 x 10-3 mm2/s, p = 0.581). An improvement in xerostomia was found in 13 patients at one year post-RT. Multivariate analysis revealed 4 significant predictors for the improvement of xerostomia, including dose to parotid glands (p = 0.009, odds ratio [OR] = 0.639), the ADC of submandibular glands (p = 0.013, OR = 3.295), pADCmax (p = 0.024, OR = 0.474), and pTmax (p = 0.017, OR = 0.729) at one week post-RT. Conclusion: The ADC value is a sensitive indicator for salivary gland dysfunction. DW-MRI is potentially useful for noninvasively predicting the severity of radiation-induced xerostomia.

Enhancement of high-order harmonics in a plasma waveguide formed in clustered Ar gas

Geng, Xiaotao,Zhong, Shiyang,Chen, Guanglong,Ling, Weijun,He, Xinkui,Wei, Zhiyi,Kim, Dong Eon The Optical Society 2018 Optics express Vol.26 No.3

Establishment and evaluation of a murine anb3-integrinexpressing cell line with increased susceptibility to Foot-and-mouth disease virus

Wei Zhang,Kaiqi Lian,Fan Yang,Yang Yang,Zhijian Zhu,Zixiang Zhu,Weijun Cao,Ruoqing Mao,Ye Jin,Jijun He,Jianhong Guo,Xiangtao Liu,Haixue Zheng 대한수의학회 2015 Journal of Veterinary Science Vol.16 No.3

Integrin anb3 plays a major role in various signaling pathways, cell apoptosis, and tumor angiogenesis. To examine the functions and rolesof anb3 integrin, a stable CHO-677 cell line expressing the murine anb3 heterodimer (designated as “CHO-677-manb3” cells) wasestablished using a highly efficient lentiviral-mediated gene transfer technique. Integrin subunits an and b3 were detected at the gene andprotein levels by polymerase chain reaction (PCR) and indirect immunofluorescent assay (IFA), respectively, in the CHO-677-manb3 cellline at the 20th passage, implying that these genes were successfully introduced into the CHO-677 cells and expressed stably. A plaque-formingassay, 50% tissue culture infective dose (TCID50), real-time quantitative reverse transcription-PCR, and IFA were used to detect the replicationlevels of Foot-and-mouth disease virus (FMDV) in the CHO-677-manb3 cell line. After infection with FMDV/O/ZK/93, the cell line showeda significant increase in viral RNA and protein compared with CHO-677 cells. These findings suggest that we successfully established a stableanb3-receptor-expressing cell line with increased susceptibility to FMDV. This cell line will be very useful for further investigation of anb3integrin, and as a cell model for FMDV research.