Portfolio Decision Model based on the Strategic Adjustment Capacity: A Bionic Perspective on Bird Predation and Firm Competition

Chao Mao,Shou Chen,Duan Liu 한국유통과학회 2015 유통과학연구 Vol.13 No.1

Purpose – This study integrates a corporate competition system with a bird predation system to examine how organizational strategic adjustment capacity influences firm performance. By proving the prominent effects on performance, a financial vector is constructed to represent corporate strategic adjustment results, and an operation capacity vector is constructed, which can be categorized as a parameter for locating birds. All these works help us to propose a new method of investment, the portfolio decision model based on the strategic adjustment capacity. Research design, data, and methodology – Strategic adjustment capacity can be decomposed into three aspects: the organizational learning capacity from the top firms, the extent to which firms maintainor rely on the best operational capacity vector in history, and the ability to eliminate the disadvantages or retain the advantages of the operation capacity vector from the previous year. The method of solving cyclic equations is designed to evaluate strategic adjustment. Firms manufacturing specialized equipment are chosen to test the effects of the strategic adjustment capacity on three aspects of firm performance. Results – There is a positive correlation between the capacity to learn from the best firms and performance improvement. The relationship between the dependence or maintenance of a firm’s advantages and performance improvement is a U-shape curve, and there is no significant effect of inertial control on performance improvement. Conclusions – A firm’s competition system is a sophisticated adaptation, and competitive advantage and performance can be investigated based on the principles of competition in nature.

Structural Equation Modeling to Analyze the Critical Driving Factors and Paths for Off-site Construction in China

Chao Mao,Guiwen Liu,Liyin Shen,Xiangyu Wang,Jun Wang 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.8

Off-site Construction (OSC) is an alternative to conventional construction. However, China lags behind developed countries interms of its OSC development. The chief goal of this study is to demonstrate the critical driving forces and solutions that promoteOSC development. A total of 21 hypotheses are established to present the interrelations among eight driving forces. Based on 176valid responses from developers in mainland China, a structural equation model is built to explore the key solutions and the criticaldriving forces. Most driving forces, such as Pursuit of Sustainable Competitiveness (PSC), Governmental Policies and Regulations(GPR), Technological Innovation (TI), Corporate Social Responsibility (CSR), and Construction Market Demand (CMD), can affecta Corporation’s Willingness and Behavior (CWB) in adopting OSC through two mediating factors, namely, Economic Benefits (EB)and social and environmental benefits. The findings highlight five main driving solutions to promote OSC, namely, “PSC → EB →CWB,” “PSC → TI → EB → CWB,” “GPR → TI → EB → CWB,” “GPR → CSR → CWB,” and “GPR → CMD → CWB.”Governments and project clients are also identified as important players in the development of OSC in China. These results provide avaluable reference for the government to understand the underlying interrelationships among the driving forces and key solutions tothe development of OSC in China.

Genetically Encoded Biosensor Engineering for Application in Directed Evolution

Mao Yin,Huang Chao,Zhou Xuan,Han Runhua,Deng Yu,Zhou Shenghu 한국미생물·생명공학회 2023 Journal of microbiology and biotechnology Vol.33 No.10

Although rational genetic engineering is nowadays the favored method for microbial strain improvement, building up mutant libraries based on directed evolution for improvement is still in many cases the better option. In this regard, the demand for precise and efficient screening methods for mutants with high performance has stimulated the development of biosensor-based highthroughput screening strategies. Genetically encoded biosensors provide powerful tools to couple the desired phenotype to a detectable signal, such as fluorescence and growth rate. Herein, we review recent advances in engineering several classes of biosensors and their applications in directed evolution. Furthermore, we compare and discuss the screening advantages and limitations of two-component biosensors, transcription-factor-based biosensors, and RNA-based biosensors. Engineering these biosensors has focused mainly on modifying the expression level or structure of the biosensor components to optimize the dynamic range, specificity, and detection range. Finally, the applications of biosensors in the evolution of proteins, metabolic pathways, and genome-scale metabolic networks are described. This review provides potential guidance in the design of biosensors and their applications in improving the bioproduction of microbial cell factories through directed evolution.

Genetic Diversity and Geographical Differentiation of Desmodium triflorum (L.) DC. in South China Revealed by AFLP Markers

Mao-feng Yue,Ren-chao Zhou,Ye-lin Huang,Guo-rong Xin,Su-hua Shi,Li Feng 한국식물학회 2010 Journal of Plant Biology Vol.53 No.2

High levels of genetic variation enable species to adapt to changing environments and provide plant breeders with the raw materials necessary for artificial selection. In the present study, six AFLP primer pairs were used to assess the genetic diversity of Desmodium triflorum (L.)DC. from 12 populations in South China. A high percentage of polymorphic loci (P=76.16%) and high total gene diversity (HT=0.310) were found, indicating that the genetic diversity of D. triflorum is high at the species level. Genetic diversity was also relatively high at the population level (P=55.85%, He=0.230). The coefficient of gene differentiation among populations (GST) was 0.255, indicating that while most genetic diversity resided within populations, there was also considerable differentiation among populations. AMOVA also indicated 24.29% of the total variation to be partitioned among populations (ΦST=0.243). UPGMA clustering analysis based on genetic distances showed that the 12 populations could be separated into three subgroups: an eastern, a western, and a central-southern subgroup. However, a Mantel test revealed no significant correlation (r=0.286, p=0.983)between the geographical distances and genetic distances separating these populations; mountain barriers to gene flow and human disturbance may have confounded these correlations. The present study has provided some fundamental genetic data that will be of use in the exploitation of D. triflorum.

Feedback control of thermal frequency drift for a normal conducting cyclotron under CW operation

Chao Chujie,Chen Gen,Mao Yuzhou,Chen Yonghua,Zhang Xin 한국물리학회 2023 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.83 No.7

A normal conducting cyclotron is developed for medical purposes, which consists of the magnet, RF cavity, ion source, vacuum system, cooling system and control system. Especially, the RF cavity, which establishes an electric feld to accelerate charged particles, is one of the most critical and complex components in an cyclotron. During long-term continuous wave (CW) operation of the cavity, there will be a rise in temperature in the RF cavity due to its own thermal loss. This can lead to mechanical deformation and frequency deviation of the cavity, and thereby having a negative impact on its performance. That is, it will increase the refected power, lower the beam current, and cause instability in the cyclotron's operation. Therefore, based on the results of multi-physics analysis, which indicated that the frequency deviation is caused by thermal loss, an automatic frequency feedback control system was designed. In addition, a CW(25 kW) operation was tested, the results displayed that the maximum refected power decreased from 729 to 70 W, and the maximum detuning phase decreased from 12.26° to 1.9° by applying the feedback control system. The frequency of the cavity shifted approximately −22.8 kHz. The experimental results demonstrate that the frequency feedback control system is efective in compensating for frequency deviation caused by thermal loss.

Design and performance of the digital LLRF control system for isotope production cyclotron

Chao Chujie,Chen Gen,Mao Yuzhou,Chen Yonghua,Ding Kaizhong,Zhang Xin 한국물리학회 2023 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.82 No.2

The project of a 14 MeV cyclotron used for isotope production was developed by ASIPP (Hefei, China). To generate stable radionuclides by the cyclotron, the beam parameters should be stabilized rigorously. Therefore, a digital low-level RF system (LLRF) was designed and built to stabilize acceleration voltage and control the resonance of the cyclotron. The system can be confgured to use Non-IQ sampling techniques, resulting in a high performance RF control without the need of very high speed acquisition hardware. In this paper, the functional requirements of LLRF systems are analyzed, including the two feedback control loops, contain tuning loop, the amplitude loop, and the automatic conditioning process. Meanwhile, the hardware design of the FPGA-based core processing board is presented. In experiments, the automatic conditioning process was tested, which certifes the process can greatly shorten the conditioning time. The stability of the cavity voltage and control efect for the resonant frequency has also been measured, and the results show that the amplitude stability is better than 0.0092% under beam loading operation. Experimental results in diferent operating modes prove that the digital LLRF system can meet the demands of RF control systems for isotope production cyclotron.

Identifying Opinion Leader in the Internet Forum

Chao Wu,Chunlin Li,Wei Yan,Youlong Luo,Xijun Mao,Shumeng Du,Mingming Li 보안공학연구지원센터 2015 International Journal of Hybrid Information Techno Vol.8 No.11

Opinion leader is an authority person who has great influence in BBS. Their linguistic behavior has a huge impact on net citizen’s behavior and thought. In this paper, we propose an algorithm called OLRA (Opinion Leader PageRank Algorithm) based on topic-field to identify opinion leaders in the Internet forum. In the algorithm the closeness degree factor and sentiment analyses are taken into consideration. Meanwhile, these two authority values are defined as the weight of links among users. The data is collected from a number of posts on Tianya forum which is a famous forum in China. In the experiment, the algorithm is compared with Interest-based PageRank algorithm, online time Algorithm, and Experience-based Algorithm, the result shows that the OLRA algorithm can identify opinion leaders than others in the Internet forum effectively.

Study of Deformation Mechanisms of a High-Purity α-Titanium Plate Under Monotonic Loading with the EVPSC-TDT Model

Chao Ma,Xing Duan,Xiaoqian Guo,Hua Qiao,Lianying Zhang,Xianbiao Mao,Peidong Wu 대한금속·재료학회 2023 METALS AND MATERIALS International Vol.29 No.2

The deformation mechanisms of a rolled high-purity α-titanium plate under monotonic loading along the rolling direction(RD), transverse direction (TD), and normal direction (ND) are investigated by the Elastic Visco-Plastic Self-Consistent(EVPSC) model, which incorporates a Twinning and De-Twinning (TDT) scheme to describe twinning behavior duringstraining. In the EVPSC-TDT model, plastic deformation is assumed to be accommodated by prismatic, basal and pyramidal⟨c + a⟩ slip modes as well as the 10̄12 extension and 11̄22 contraction twin modes. Numerical results based on theEVPSC-TDT model are in good agreement with the corresponding experimental data. The tension–compression asymmetry,anisotropic initial yielding and strain hardening behavior are interpreted in terms of the predicted relative activities of variousdeformation modes, twin volume fractions and texture evolutions. It is demonstrated that twinning plays an important rolein tension–compression asymmetry and plastic anisotropy, which is closely related to the loading direction with respect tocrystal orientations in the initial texture. In addition, it can be concluded that the TDT scheme permits better performancein describing twinning-associated deformation behavior for the rolled high-purity α-titanium plate than the PredominantTwin Reorientation (PTR) model even when detwinning is not involved.

ZSCC suppression method for parallel three‑level inverters based on model predictive control with virtual location vector

Ling Mao,Yuankai Li,Chao Pan,Jianlin Yang,Qin Hu,Yuncong Zheng,Jinbin Zhao 전력전자학회 2024 JOURNAL OF POWER ELECTRONICS Vol.24 No.4

Parallel three-level neutral point clamped (3L-NPC) inverters are widely used in power conversion applications, such as new energy generation and high voltage inverters. However, the zero-sequence circulating current (ZSCC) between two inverters degrades the whole performance of the system. To suppress the ZSCC in parallel inverters and improve the quality of output current, this study proposes an MPC strategy based on the virtual location vector. First, to reduce the computational burden of MPC, the virtual location vector is constructed by the output current of two inverters so that the control of the parallel inverters is similar to that of a single inverter. Then, the virtual location vector is obtained by using the direct power control method. Finally, the sets of candidate voltage vectors for MPC are determined on the basis of this reference voltage vector and the magnitude of ZSCC. Moreover, the optimal vectors calculated by MPC are assigned to the two inverters. Compared with the traditional MPC strategy, the MPC strategy proposed in this study has better steady state and transient performance with less computational burden. The proposed method is validated in simulation and experimental platforms.

HYDRAULIC CHARACTERISTICS OF DOUBLE-BEND SPILLWAY

YE MAO,WU CHAO,CHEN YUNLIANG,ZHOU QIN 한국수자원학회 2005 한국수자원학회 학술대회 Vol.2005 No.1