A Study of the Content Validity of Reading Comprehension Tests in NMET II

Zhen-Jie Liu,Ming-Hao Jin 대한언어학회 2018 언어학 Vol.26 No.4

Liu, Zhen-Jie & Jin, Ming-Hao. (2018). A study of the content validity of reading comprehension tests in NMET II. The Linguistic Association of Korea Journal, 26(4), 103-124. Based on Bachman and Palmer’s (1996) framework of task characteristics, this paper aims to compare the reading comprehension tests of the 2013-2017 National Matriculation English Test II (NMET II) with the requirements of the New Curriculum Standards and Testing Syllabus, in particular, concerning the content validity of the tests in terms of the characteristics of input and expected responses. The implications of this study are discussed for test designers, teachers, and students. The results show that reading comprehension tests from 2013 to 2017 basically meet the requirements of the New Curriculum Standard and Testing Syllabus and have a high content validity. In terms of the characteristics of input, the length, reading speed, and readability of comprehension passages are appropriate for students; however, the distribution of topics and genres in each year is uneven. In terms of the characteristics of expected responses, the wordings of questions and the design of question items are reasonable. However, the response type is mainly restricted to selected response questions (multiple-choice), and the measure of reading skills coverage is unbalanced.

One-Step Oxidation of Benzene Producing Eight High Value Compounds Using Nitric Acid and Hydrogen Peroxide

Zhen-xue Liu,Zhong-xue Gan,Jun-jie Gu,Qing-feng Song 대전대학교 환경문제연구소 2015 환경문제연구소 논문집 Vol.19 No.-

Benzene was oxidized by binary oxidants composed of nitric acid and hydrogen peroxide at 80℃. The product obtained was analyzed with gas chromatograph-mass spectrometer. Eight high value compounds, 2-nitrophenol, 2-chloro-6-nitrophenol, 4-chloro-2- nitrophenol, 2-chloro-4-nitrophenol, 2,4-dinitrophenol, 4-nitrophenol, 2,6-dinitrophenol and 2-chloro-4,6-dinitro-phenol were found, which they have high contents in the range from 4.28% to 32.52%. These compounds are very widely used in organic synthesis. e.g., synthesizing dye, medicines and chemical reagents, pesticide, explosive, polymer, etc.

The Dynamic Mechanical Properties for Recycled Aggregate Concrete under Tensile-Compressive States

Zhen-Jun He,Zhi-qiang Wang,Meng-jia Ding,Zhen-wei Wang,Xiao-jie Zhang,Lian-shuo Liu 대한토목학회 2020 KSCE Journal of Civil Engineering Vol.24 No.5

The experiments under biaxial tensile-compressive (T-C) complex stress were carried out for two kinds of substitution percentages of recycled coarse aggregate (RCA) on biaxial proportional loading (α = σ1:σ3 =1:0, 0: -1, 0.05: -1, 0.1: -1, 0.25: -1, 0.5: -1, 1: -1 and-1: -1) and four loading deformation rates of 10−5/s, 10−4/s , 10−3/s, and 10−2/s. The research was completed in the static-dynamic true triaxial machine. The experimental phenomena indicate the tensile failure appears in these specimens of recycled aggregate concrete (RAC) under biaxial T-C stress states. The dynamic mechanical behavior for RAC under biaxial T-C loadings was affected by the strain rates, stress ratios and its substitution percentages of RCA. Accompanied by the increase of strain rates, its strength of RAC is improved. As the tensile stress increases, its compressive strength decreases. The T-C strengths for RAC under biaxial T-C states are less than its corresponding uniaxial T-C strengths at a certain identical strain rates, respectively. Considering the effect of loading rates, a new tensile-compressive failure criterion is established under complex stress states.

Species Classification and Quality Assessment of Chaihu (Radix Bupleuri) Based on High-Performance Liquid Chromatographic Fingerprint and Combined Chemometrics Methods

Xiao-Jie Li,Jie Hu,Zhen-Yu Li,Xue-Mei Qin,Li-Zeng Zhang,Xiao-Qing Guo 대한약학회 2011 Archives of Pharmacal Research Vol.34 No.6

A high-performance liquid chromatographic (HPLC) method was established to analyze 36 Chaihu (Radix Bupleuri) samples collected from three species (Bupleurum chinense DC., B. scorzonerifolium Willd. and B. smithii Wolff.). Addition of trifluoroacetic acid into the mobile phase resulted in fingerprint chromatograms with stable baselines. There were thirty-two characteristic peaks in the standard fingerprint of B. chinense DC. Different recognition pattern methods, including similarity analysis (SA), hierarchical cluster analysis (HCA), principal component analysis (PCA) and partial least squares-discrimination analysis (PLS-DA) were utilized to analyze the 36 samples based on the contents of chemical constituents. Consistent results from SA, HCA and PCA analysis illustrated the rationalisation for why B. smithii Wolff. was not quoted in the Chinese Pharmacopoeia and classified samples were in agreement with their species. PLS-DA loading plots showed the chemical markers which had the most influences on the separation among different species. However, SA, HCA and PCA could not differentiate between wild and cultivated B. chinense DC. as well as between samples from different provinces. HPLC fingerprint in combination with chemometric techniques provided a very flexible and reliable method for homogeneity evaluation and quality assessment of traditional Chinese medicine.

Effects of Celecoxib on Cycle Kinetics of Gastric Cancer Cells and Protein Expression of Cytochrome C and Caspase-9

Wang, Yu-Jie,Niu, Xiao-Ping,Yang, Li,Han, Zhen,Ma, Ying-Jie Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.4

Objective: This investigation aimed to determine effects of celecoxib on the cell cycle kinetics of the gastric cancer cell line MGC803 and the mechanisms involved by assessing expression of cytochrome C and caspase-9 at the protein level. Methods: Cell proliferation of MGC803 was determined by MTT assay after treatment with celecoxib. Apoptosis was assessed using fluorescence staining and cell cycle kinetics by flow cytometry. Western blotting was used to detect the expression of caspase-9 protein and of cytochrome C protein in cell cytosol and mitochondria. Results: Celecoxib was able to restrain proliferation and induce apoptosis in a dose- and time-dependent manner, inducing G0/G1 cell cycle arrest, release of cytochrome C into the cytosol, and cleavage of pro-caspase-9 into its active form. Conclusion: Celecoxib can induce apoptosis in MGC803 cells through a mechanism involving cell cycle arrest, mitochondrial cytochrome C release and caspase activation.

Rhein lysinate decreases inflammation and adipose infiltration in KK/HlJ diabetic mice with non-alcoholic fatty liver disease

Jie Wei,Yong-Zhan Zhen,Ju Cui,Fa-Lin He,Tao Shen,Gang Hu,Xiao-Hong Ren,Yajun Lin 대한약학회 2016 Archives of Pharmacal Research Vol.39 No.7

The objective of this study was to investigate the protective effects of rhein lysinate (RHL) on the liver. Mice were divided into four groups: C57BL/J control, the KK/HlJ diabetic model, and 25 and 50 mg/kg/day RHLtreated KK/HlJ groups. The KK/HlJ diabetic mouse model was made by injecting STZ and feeding mice diabetic food. At 16 weeks, mice were sacrificed and their livers were harvested. The results indicated that compared with the C57BL/J control group, the body weights, liver weights and liver weight-to-body weight ratio were increased in KK/HlJ diabetic mice; however, these values were decreased following treatment with RHL. Compared with the C57BL/J control, KK/HlJ diabetic mice had a significantly lower level of SOD and GSH-px in their livers, but had a significantly higher level of MDA. However, these effects were ameliorated by RHL. Hepatic adipose infiltration was observed in KK/HlJ mice, but not in C57BL/J mice. RHL decreased the incidence of hepatic adipose infiltration and significantly decreased the expression of TNF-a, IL-6, NF-jB, SREBP-1c, and Fas, as well as the phosphorylation of NF-jB in the liver. In conclusion, RHL can improve hepatic function by decreasing hepatic adipose infiltration and the expression of inflammatory factors.

Preparation and Characterization of L-Phenylalanine Modified Chitosan Resin for Aromatic Amino Acid Adsorption

Jie Zhang,Hongmei Chen,Xiaohua Zhou,Zhen Zhou,Lin Chen 한국고분자학회 2014 Macromolecular Research Vol.22 No.5

A novel L-phenylalanine modified chitosan resin (PCR) was prepared for adsorption of aromatic aminoacid from mixed amino acids solution. The structure and properties of PCR were observed by FTIR, 13C NMR, AFMand SEM. PCR was found to swell rather than dissolve in acidic mediums from its solubility and swelling behaviorexperiments. Batch adsorption experiments were performed to evaluate the adsorption capacity, selectivity and reusabilityas well as its application to the removal of L-phenylalanine and tyrosine from mixed amino acids solution. The results indicated that the maximum adsorption capacity of PCR was 309.44 mg/g in sole L-phenylalanine solutionat 25 oC. The selectivity coefficient of L-phenylalanine, tyrosine and other amino acids on PCR indicated an overallpreference for L-phenylalanine and tyrosine, which were much higher than that of non-modified chitosan resin. PCRcould be reused for ten times with about 6.26% loss. This suggests that PCR is a very promising adsorbent for theselective removal of aromatic amino acid from mixed amino acids solution.

Flow separation control of two kinds of microvortex generators for a supersonic spinning projectile

Jie Ma,Zhen-gui Huang,Zhihua Chen,Da-wen Xue,Jun-li Han 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.1

Previous studies have shown that Microvortex generators (MVGs) can effectively control the flow separation of supersonic boundary layer. To improve the flight stability of a spinning projectile, two kinds of MVGs, micro ramps and vanes, are applied to control the flow separation of an original standard 155 mm projectile, respectively. Numerical simulations were performed with the use of Detached eddy simulation (DES) method, and the flow fields of the projectile with and without micro MVGs were simulated, the characteristics of the boundary layer and aerodynamic data of three cases were compared and discussed. The numerical results reveal that the effect of the MVGs control is obvious, but their mechanisms are different, and the vanes are more effective than the ramp in the boundary layer control. However, they can both improve the lift and pitching moment of the projectile, and eliminate their oscillations; as a result, its flight stability and firing dispersion can be enhanced. Our results can provide important guidance for improving the flight quality of supersonic projectiles.

Optimizations for Mobile MIMO Relay Molecular Communication via Diffusion with Network Coding

Zhen Cheng,Jie Sun,Jun Yan,Yuchun Tu 한국인터넷정보학회 2022 KSII Transactions on Internet and Information Syst Vol.16 No.4

We investigate mobile multiple-input multiple-output (MIMO) molecular communication via diffusion (MCvD) system which is consisted of two source nodes, two destination nodes and one relay node in the mobile three-dimensional channel. First, the combinations of decode-and-forward (DF) relaying protocol and network coding (NC) scheme are implemented at relay node. The adaptive thresholds at relay node and destination nodes can be obtained by maximum a posteriori (MAP) probability detection method. Then the mathematical expressions of the average bit error probability (BEP) of this mobile MIMO MCvD system based on DF and NC scheme are derived. Furthermore, in order to minimize the average BEP, we establish the optimization problem with optimization variables which include the ratio of the number of emitted molecules at two source nodes and the initial position of relay node. We put forward an iterative scheme based on block coordinate descent algorithm which can be used to solve the optimization problem and get optimal values of the optimization variables simultaneously. Finally, the numerical results reveal that the proposed iterative method has good convergence behavior. The average BEP performance of this system can be improved by performing the joint optimizations.

LCL Resonant Compensation of Movable ICPT Systems with a Multi-load

Jie Hua,Hui-Zhen Wang,Yao Zhao,Ai-Long Zou 전력전자학회 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.6

Compared to LC resonance, LCL resonance has distinct advantages such as a large resonant capability, low voltage and current stresses of the power device, constant voltage or current output characteristics, and fault-tolerance capability. Thus, LCL resonant compensation is employed for a movable Inductive Contactless Power Transfer (ICPT) system with a multi-load in this paper, which achieves constant current output characteristics. Peculiarly, the primary side adopts a much larger compensation inductor than the primary leakage inductor to lower the reactive power, reduce the input current ripple, generate a large current in the primary side, and realize soft-switching. Furthermore, this paper proposes an approximate resonant point for large inductor-ratio LCL resonant compensation through fundamental wave analysis. In addition, the PWM control strategy is used for this system to achieve constant current output characteristics. Finally, an experimental platform is built, whose secondary E-Type coils can ride and move on a primary rail. Simulations and experiments are conducted to verify the effectiveness and accuracy of both the theory and the design method.