OFDM MIMO radar waveform design for targets identification

Ting Bai,Nae Zheng,Song Chen 한국전자통신연구원 2018 ETRI Journal Vol.40 No.5

In order to obtain better target identification performance, an efficient waveform design method with high range resolution and low sidelobe level for orthogonal frequency division multiplexing (OFDM) multiple‐input multiple‐output (MIMO) radar is proposed in this paper. First, the wideband CP‐based OFDM signal is transmitted on each antenna to guarantee large bandwidth and high range resolution. Next, a complex orthogonal design (COD) is utilized to achieve code domain orthogonality among antennas, so that the spatial diversity can be obtained in MIMO radar, and only the range sidelobe on the first antenna needs suppressing. Furthermore, sidelobe suppression is expressed as an optimization problem. The integrated sidelobe level (ISL) is adopted to construct the objective function, which is solved using the Broyden‐Fletcher‐Goldfarb‐Shanno (BFGS) algorithm. The numerical results demonstrate the superiority in performance (high resolution, strict orthogonality, and low sidelobe level) of the proposed method compared to existing algorithms.

A Comparative Study on Antecedents to the Customer Satisfaction with Cross-Border E-commerce in Korea and China

Ting, Bai,Nam, Inwoo Korean Marketing Association 2016 ASIA MARKETING JOURNAL Vol.18 No.2

As one of the most popular forms of electronic commerce, cross-border e-commerce provides numerous consumer benefits, such as broad and deep product assortments at low prices. However, consumers tend to exhibit high involvement in cross-border e-commerce purchases due to high risks associated with such purchases. The paper focuses on identifying causal relationships between e-commerce website traits (i.e., website trustworthiness, interactivity and convenience) and consumer satisfaction and along with loyalty. We proposed a reflective-reflective hierarchical model (first-order reflective and second-order reflective model) and used the Partial Least Square Analysis Statistical method to test the hypotheses. The results demonstrated that website trustworthiness, convenience and interactivity were all positively related to consumer satisfaction. Also, higher satisfaction led to stronger customer loyalty, which may well increase revisit intentions. We also compared the strength of each path from a website trait to satisfaction. Results illustrated that the path from website convenience to satisfaction is the strongest among the three website traits. In addition, we separately examined differences within Korean group and Chinese group. No statistically significant difference among website traits was found within Korean group. However, within Chinese group, we found that website convenience is the most important predictor of satisfaction. This indicates that Chinese consumers are more concerned about the website convenience than interactivity and trustworthiness when they make cross-border e-commerce purchases. Moreover, this study investigated possible differences between Korean and Chinese group. We used multi-group analysis of Smart PLS 3.0 to test the results. It was shown that the two groups do not display statistically significant difference in trustworthiness, interactivity, or convenience in influencing customer satisfaction. Finally, we presented further implications which are useful for understanding of the proposed model. Limitations and improvements of this research were presented, too.

Analysis of Antecedents to Customer Satisfaction in Cross-Border E-Commerce

백정(Ting Bai),노태석(Tae Seok Rho),남인우(In Woo Nam) 중앙대학교 한국전자무역연구소 2016 전자무역연구 Vol.14 No.3

연구목적: 소비자들은 해외직구 서비스를 통하여 해외에 직접 나가지 않고도 손쉽게 외국 상품들을 구입할 수 있게 되었다. 그러나 해외직구의 인기에도 불구하고 소비자들은 해외직구의 경우에 국내에서 물건을 구입하는 것보다 더 많은 위험을 인지하고 교환이나 환불의 어려움으로 인한 불만족을 경험하는 등 서비스의 개선의 여지를 남겨두고 있다. 이에 해외직구 사이트의 매니저는 해외직구 고객의 니즈를 면밀히 파악할 필요가 있다. 이에 이 논문은 해외직구 사이트의 고객의 종합 만족도에 영향을 미치는 요소들을 조사하여 실증분석을 실시하였다. 논문구성/논리: 소비자의 만족도에 영향을 끼치는 큰 요소들로서 신뢰성, 상호작용성, 편의성을 제시하고 각각의 컨스트럭트에 포함되는 하위 컨스츠럭트들을 제시하였다. 즉 신뢰성의 요소에는 세부적으로 보안보증 신뢰성, 품질신뢰성, 배송신뢰성, 평판 신뢰성을 설정하고 상호작용성의 요소에는 통제성, 양방향 소통, 그리고 동시성을 설정하였다. 마지막으로 편의성의 요소로는 탐색 편의성, 접근 편의성, 거래 편의성을 설정하였다. 결과: 200명의 한국 소비자를 대상으로 Partial Least Square 분석으로 가설이 검정되었으며 분석 결과 품질 신뢰성, 배송 신뢰성, 모든 편의성 요소들이 소비자의 만족에 정의 영향을 주는 것으로 나타났다. 독창성/가치: 이 논문의 가치는 그동안 많은 연구가 이루어지지 않은 국제간의 B2C전자상거래라고 할 수 있는 해외 직구에 관한 연구라는 점을 들 수 있고 그 만족도에 영향을 끼치는 요소들에 대한 선도적인 연구라는 점을 말할 수 있다. Purpose: Cross-border e-commerce refers to international online trade that enables customers to purchase products from a seller across national borders. Despite the growing popularity of the cross-border e-commerce, customers have concern regarding this new mode of shopping. Many participants were dissatisfied with the exchange and refund processes, unstandardized product quality, and insufficient after-sales services. They believe that these major areas of the cross-border shopping environment need to be improved. Therefore, the key challenge before cross-border e-commerce is understand customers’ needs in order to enhance customer satisfaction. In this study, we proposed factors that affect consumer satisfaction. Composition/Logic: Based on extant literature on the e-commerce, we proposed that trustworthiness, interactivity, and convenience are major factors that affect customer satisfaction. We also identified sub-dimensions within these factors. Findings: This research tested factors affecting customer satisfaction in cross-border e-commerce using Partial Least Squares Analysis. The results show that trustworthiness of the product quality, and trustworthiness on delivery service, as well as search convenience, access convenience, and transaction convenience were positively related to consumer satisfaction. Originality/Value: Despite the growing popularity of cross-border e-commerce, enough research has not been conducted on the issue. This research contributes to the literature by suggesting the key determinant of customer satisfaction in cross border e-commerce.

Study on the Control and Projective Synchronization of a New Fractional-order Chaos System

Shao Ke-Yong,Chen Bai-Quan,Wang Ting-Ting,Xu Xiang,Zhang Ting-Ting,Ma Di 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.10

In this paper, a new fractional-order chaotic system was studied, and the basic dynamic properties of the new system were analyzed. The control of the new system in unstable equilibrium point was realized by designing the reasonable nonlinear controller. Further, we investigated the projective synchronization problem about fractional order chaotic systems with different dimensions, the appropriate controller was designed to achieve the projective synchronization of a four-dimensional drive system and a three-dimensional response system by reducing the dimension. With the numerical simulation of Matlab, the feasibility of the scheme was verified.

Trastuzumab combined with irinotecan in patients with HER2-positive metastatic colorectal cancer: A phase II single-arm study and exploratory biomarker analysis

Ting Xu,Xicheng Wang,Ying Xin,Zhenghang Wang,Jifang Gong,Xiaotian Zhang,Yanyan Li,Congcong Ji,Yu Sun,Feilong Zhao,Depei Huang,Yuezong Bai,Jian Li,Lin Shen 대한암학회 2023 Cancer Research and Treatment Vol.55 No.2

Purpose The human epidermal growth factor receptor 2 (HER2) is an established therapeutic target for various kinds of solid tumors. HER2 amplification occurs in approximately 1% to 6% of colorectal cancer. In this study, we aimed to assess the efficacy and safety of trastuzumab in combination with chemotherapy in HER2-positive metastatic colorectal cancer (mCRC). Materials and Methods An open-label, phase II trial (Clinicaltrials.gov: NCT03185988) was designed to evaluate the antitumor activity of trastuzumab and chemotherapy in HER2-positive digestive cancers excluding gastric cancer in 2017. Patients from this trial with HER2-positive, KRAS/BRAF wild-type, unresectable mCRC were analyzed in this manuscript. Eligible patients were treated with trastuzumab (8 mg/kg loading dose and then 6 mg/kg every 3 weeks) and irinotecan (120 mg/m2 days 1 and 8 every 3 weeks). The primary endpoint was the objective response rate. Results Twenty-one HER2-positive mCRC patients were enrolled in this study. Seven patients (33.3%) achieved an objective res-ponse, and 11 patients (52.4%) had stable disease as their best response. The median progression-free survival (PFS) was 4.3 months (95% confidence interval, 2.7 to 5.9). Four of the 21 patients (19.0%) had grade 3 adverse events, including leukopenia, neutropenia, urinary tract infection, and diarrhea. No treatment-related death was reported. Exploratory analyses revealed that high tumor tissue HER2 copy number was associated with better therapeutic response and PFS. Alterations in the mitogen-activated protein kinase pathway, HER2 gene, phosphoinositide 3-kinase/AKT pathway, and cell cycle control genes were potential drivers of trastuzumab resistance in mCRC. Conclusion Trastuzumab combined with chemotherapy is a potentially effective and well-tolerated therapeutic regimen in mCRC with a high HER2 copy number.

Optimization of medium components for D-ribose production by transketolase-deficient Bacillus subtilis NJT-1507

Hanjie Ying,Ting Fang,Xiaochun Chen,Nan Li,He Song,Jianxin Bai,Jian Xiong 한국화학공학회 2010 Korean Journal of Chemical Engineering Vol.27 No.6

Statistical experimental designs were used to optimize the composition of culture media for the production of D-ribose by Bacillus subtilis. A fractional factorial design 2(5-2) was used to determine medium components that significantly affected D-ribose production. The concentrations of glucose and (NH4)2SO4 were the significant factors. Central composite design and response surface methodology were then used to estimate the quadratic response surface and determine the factor levels for maximum production of D-ribose. Finally, the optimal medium composition was obtained (g/L): glucose, 172.75; (NH4) 2SO4, 13.2; yeast powder, 4; corn steep liquor, 8 and MnSO4, 0.5. This optimization strategy increased D-ribose production from 73.21 g/L to 88.57 g/L, an increase of 22% compared with the original conditions. The D-ribose production yield to glucose concentration was also enhanced from 0.37 g/g to 0.52 g/g. Confirmatory experiments were also performed to demonstrate the accuracy of the model. Under the optimal medium using ammonia to control pH in a 5 L fermenter, the D-ribose yield was increased to 95.28 g/L after 3 days of cultivation at 37 oC.

Coupling conversion of methanol and 1-butylene to propylene on HZSM-5 molecular sieve catalysts prepared by different methods

Xin Zhang,Ting Bai,Xiling Liu,Tengfei Chen,Wentao Fan 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.7

A series of HZSM-5 catalysts were synthesized by different methods. The physicochemical properties of the HZSM-5 catalysts were characterized by XRD, SEM, N2 isothermal adsorption-desorption, NH3-TPD, Py-IR and TGA, respectively. The results indicated that different preparation conditions lead to different morphologies, textures and the distribution of acid sites. The nanosized HZSM-5 catalysts exhibited better catalytic reactivity and coke capacity than the micro-sized HZSM-5 because nanosized HZSM-5 had larger specific surface area, higher pore volume, more exposed channels and more accessible acid sites. The large particles of NZ-3 in a reasonable range and the smooth surface were conducive to product diffusion; therefore, NZ-3 exhibited higher specific propylene yield and stability than the other nanosized catalysts. The moderate density and distribution of acid sites on NZ-3 also favored the formation of propylene.

Juvenoids on aphids to prolong optimal stages

Lai Rongquan,Bai Jingjing,Gu Gang,Zhou Ting,Mi Yuee,Zhang Bang,Han Meng,Bai Jianbao 한국곤충학회 2021 Entomological Research Vol.51 No.3

In recent years, Aphidius gifuensis, a critical parasitoid, has been increasingly used to control Myzus persicae in tobacco. However, problems due to inconsistent emergence and insufficient numbers of A. gifuensis to control M. persicae have arisen in artificial reproduction. Here, we investigated the effects of the juvenoids ZR-512, ZR-777, ZR-515, fenoxycarb and juvenile hormone (JH) III on the performance of M. persicae, the activities of molting enzymes and parasitism rates. The aim was to identify juvenoids that may prolong the ‘arrived too early’ optimal stages of M. persicae for A. gifuensis parasitism to address the problems mentioned above. The results showed that the developmental durations of 2nd- and 3rd-instar nymphs of the parental (F0) and offspring (F1) generations of M. persicae were significantly prolonged by juvenoid treatment. The instar durations ranged from 4.00 to 13.67 h for the parental generation and from 8.00 to 32.00 h for the offspring. M. persicae lifespan was not significantly affected by the juvenoids, whereas fecundity was. Additionally, the phenoloxidase and chitinase contents and activities in M. persicae were significantly reduced by the juvenoids, whereas the parasitism rate of A. gifuensis on M. persicae was unaffected. Our study provides information that can help prolong the ‘arrived too early’ period of effective parasitism of M. persicae nymphs by A. gifuensis and thereby benefit the large-scale artificial reproduction of A. gifuensis. These findings will enhance the biological control of M. persicae and highlight the mechanism by which juvenoids affect M. persicae development by regulating phenoloxidase or chitinase.

Cytotoxic effect of proparacaine on human corneal epithelial cells and its possible mechanisms

Su-Ran Bai,Ting-Jun Fan,T.-J. Fan 대한독성 유전단백체 학회 2017 Molecular & cellular toxicology Vol.13 No.1

Excessive use of proparacaine (PPC), a commonly used anesthetic for eye surgery, may damage the human corneal epithelium (HCEP) and impair vision. The cytotoxicity of PPC on the HCEP and its possible mechanism of action remain unclear. Therefore, we treated HCEP cells with 0.15625-5 g/L PPC for 1-28 h and monitored its effects. We found that PPC at concentrations above 0.15625 g/L (1/32 of the clinical therapeutic dose) induced dose- and time-dependent cytotoxic morphological changes and reduced cell viability. Moreover, PPC induced G1 phase arrest, plasma membrane permeability, phosphatidylserine externalization, DNA fragmentation, and apoptotic body formation. Furthermore, PPC induced activation of caspase-3, -8, and -9, disrupted mitochondrial transmembrane potential, upregulated BAD and down-regulated Bcl-2 expression, and induced the release of cytochrome c and apoptosis-inducing factor from the mitochondria. Our results indicate that PPC is cytotoxic to HCEP cells and induces apoptosis via a death receptor-mediated mitochondrion-dependent pathway.

Quantized Output Feedback Control of Networked Control Systems with Packet Dropout

Mei Yu,Shuang Bai,Ting Yang,Jianhua Zhang 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.5

This paper considers the quantized dynamic output feedback control of networked control system(NCS) with random packet dropout in both sensor-to-controller and controller-to-actuator channels. The packet losses in the two links are modeled as two independent Markov chains and the NCS is modeled as a Markov jump system. The stochastic switching signal for the quantized output feedback controller is designed to be a function of the number of successive packet loss in both of the two channels. Quantization density varies with the networked load condition. Then a sufficient condition of the stochastic stability with a prescribed H¥ performance level is established based on the Lyapunov-Krasovskii function approach. Furthermore, a quantized output feedback controller is obtained via the cone complement linearization method. Finally, simulation results are provided to verify the effectiveness of the proposed method.