建筑考古视角下凤林古城空间特点探究

陈彬彬 ( Chen¸ Bin Bin ),董健菲 ( Dong¸ Jianfei ),韩东洙 ( Han¸ Dong Soo ) 한국중국학회 2021 중국학보 Vol.97 No.-

在中国古代城市史的研究中, 关于古代都城的研究多集中在传统城市文化内核区, 而边缘地区的都城相关研究尚待完善。本次研究是在汉魏时期黑龙江地域的民族和文化背景下, 通过溯源凤林古城的历史信息, 解读都城的内部关系, 总体布局, 并与文化核心区的都城进行比较分析, 从而阐释凤林古城的都城空间特点, 丰富在建筑考古视角下对黑龙江地域古代都城方面的研究, 同时也有助于对东北地区都城历史发展脉络的建构。 In the study of ancient Chinese urban history, the study of ancient capitals mainly focuses on the core area of traditional urban culture, while the study of capitals in marginal areas remains to be improved. Under the national and cultural background of Heilongjiang region in the Han and Wei dynasties, this study traces the historical information of Fenglin ancient city, interprets the interal relationship and overall layout of the capital, and makes a comparative study with the capital in the culture core area, so as to enrich the research on the ancient capital of Heilongjiang region from the perspective of Architecturak Archaeology, and also helps to understand the historical development of the capital in Northeast China The construction of collaterals.

Physics of Dynamic Stall Vortex During Pitching Oscillation of Dynamic Airfoil

Binbin Wei,Yongwei Gao,Dong Li 한국항공우주학회 2021 International Journal of Aeronautical and Space Sc Vol.22 No.6

Dynamic stall, which has a significant effect on the aerodynamic performances of dynamic airfoils, is closely related to the physics of the dynamic stall vortex (DSV). The physics of the DSV on the NACA 0012 airfoil was experimentally studied using unsteady pressure measurements with high time accuracy. The experimental Reynolds number was Re = 1.5 × 106, and the reduced frequency was k = 0.069. The propagation of the unsteady pressure field during the dynamic stall process was analyzed in detail. The motion characteristics of the DSV were examined, including its near-wall development characteristics and near-wall evolution velocity. Moreover, the frequency characteristics of the near-wall DSV were studied using wavelet analysis combined with proper orthogonal decomposition (POD) technology. In addition, the effects of the mean angle of attack (AoA) and the amplitude on the DSV motion and frequency characteristics were examined in detail. The effects of the mean AoA on the near-wall DSV strength and the propagation velocity were linear, while the effects of amplitude were nonlinear. The mean AoA and amplitude had a significant influence on the frequency of the leading-edge vortex (LEV) at the initial stage of the DSV development (x/c = 0.10–0.20). This work allows the DSV physics to be understood more deeply.

Analysis of flow transition and separation on oscillating airfoil by pressure signature

Binbin Wei,Yongwei Gao,Long Wang,Dong Li 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.1

To have a better understanding of the unsteady aerodynamic characteristics of the airfoil which play important roles in wind turbine blade design, we investigated the boundary layer transition and separation on oscillating airfoil S809 using pressure signature captured in wind tunnel testing. The developed data processing technique of "sliding window" was applied to get useful transition and separation information. Meanwhile, the hysteresis effects of oscillation frequency on transition and separation were studied. It is found that (1) the root mean square (RMS) of pressure signature can indicate the transition and separation with the dimensionless window width of `m = 0.0015; (2) the transitional attack of angle in up stroke is larger than that in down stroke at the state of the relative chord length of x/c ≥ 0.14, while the situation is opposite at the state of the relative chord length of x/c ≤ 0.14; (3) the flow separation is advanced and the reattachment is delayed with the increase of the oscillation frequency, which results in a greater hysteresis effect. The sliding window technique, whose parameters were determined in this paper, is effective for detecting boundary layer transition and separation from pressure signature.

Catheter-Directed Thrombolysis with a Continuous Infusion of Low-Dose Urokinase for Non-Acute Deep Venous Thrombosis of the Lower Extremity

Binbin Gao,Jingyong Zhang,Xuejun Wu,Zonglin Han,Hua Zhou,Dianning Dong,Xing Jin 대한영상의학회 2011 Korean Journal of Radiology Vol.12 No.1

Objective: We wanted to evaluate the feasibility of catheter-directed thrombolysis with a continuous infusion of low-dose urokinase for treating non-acute (less than 14 days) deep venous thrombosis of the lower extremity. Materials and Methods: The clinical data of 110 patients who were treated by catheter-directed thrombolysis with a continuous infusion of low-dose urokinase for lower extremity deep venous thrombosis was analysed. Adjunctive angioplasty or/and stenting was performed for the residual stenosis. Venous recanalization was graded by pre- and posttreatment venography. Follow-up was performed by clinical evaluation and Doppler ultrasound. Results: A total of 112 limbs with deep venous thrombosis with a mean symptom duration of 22.7 days (range: 15-38 days) were treated with a urokinase infusion (mean: 3.5 million IU) for a mean of 196 hours. After thrombolysis, stent placement was performed in 25 iliac vein lesions and percutaneous angioplasty (PTA) alone was done in fi ve iliac veins. Clinically signifi cant recanalization was achieved in 81% (90 of 112) of the treated limbs; complete recanalization was achieved in 28% (31 of 112) and partial recanalization was achieved in 53% (59 of 112). Minor bleeding occurred in 14 (13%) patients, but none of the patients suffered from major bleeding or symptomatic pulmonary embolism. During followup (mean: 15.2 months, range: 3-24 months), the veins were patent in 74 (67%) limbs. Thirty seven limbs (32%) showed progression of the stenosis with luminal narrowing more than 50%, including three with rethrombosis, while one revealed an asymptomatic iliac vein occlusion; 25 limbs (22%) developed mild post-thrombotic syndrome, and none had severe post-thrombotic syndrome. Valvular refl ux occurred in 24 (21%) limbs. Conclusion: Catheter-directed thrombolysis with a continuous infusion of low-dose urokinase combined with adjunctive iliac vein stenting is safe and effective for removal of the clot burden and for restoration of the venous fl ow in patients with non-acute lower extremity deep venous thrombosis. Objective: We wanted to evaluate the feasibility of catheter-directed thrombolysis with a continuous infusion of low-dose urokinase for treating non-acute (less than 14 days) deep venous thrombosis of the lower extremity. Materials and Methods: The clinical data of 110 patients who were treated by catheter-directed thrombolysis with a continuous infusion of low-dose urokinase for lower extremity deep venous thrombosis was analysed. Adjunctive angioplasty or/and stenting was performed for the residual stenosis. Venous recanalization was graded by pre- and posttreatment venography. Follow-up was performed by clinical evaluation and Doppler ultrasound. Results: A total of 112 limbs with deep venous thrombosis with a mean symptom duration of 22.7 days (range: 15-38 days) were treated with a urokinase infusion (mean: 3.5 million IU) for a mean of 196 hours. After thrombolysis, stent placement was performed in 25 iliac vein lesions and percutaneous angioplasty (PTA) alone was done in fi ve iliac veins. Clinically signifi cant recanalization was achieved in 81% (90 of 112) of the treated limbs; complete recanalization was achieved in 28% (31 of 112) and partial recanalization was achieved in 53% (59 of 112). Minor bleeding occurred in 14 (13%) patients, but none of the patients suffered from major bleeding or symptomatic pulmonary embolism. During followup (mean: 15.2 months, range: 3-24 months), the veins were patent in 74 (67%) limbs. Thirty seven limbs (32%) showed progression of the stenosis with luminal narrowing more than 50%, including three with rethrombosis, while one revealed an asymptomatic iliac vein occlusion; 25 limbs (22%) developed mild post-thrombotic syndrome, and none had severe post-thrombotic syndrome. Valvular refl ux occurred in 24 (21%) limbs. Conclusion: Catheter-directed thrombolysis with a continuous infusion of low-dose urokinase combined with adjunctive iliac vein stenting is safe and effective for removal of the clot burden and for restoration of the venous fl ow in patients with non-acute lower extremity deep venous thrombosis.

All-organic superhydrophobic coating with anti-corrosion, anti-icing capabilities and prospective marine atmospheric salt-deliquesce self-coalesce protective mechanism

Binbin Zhang,Mengying Qiao,Weichen Xu,Baorong Hou 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.115 No.-

Water-repellent and interfacial non-wetting superhydrophobicity has great potential to addresscorrosion/icing-induced material-deterioration problems. Herein, an all-organic superhydrophobic coatingwas constructed using facile and substrate-independent spray-coating method based on PTFE andPDMS. FE-SEM, EDS, and XPS techniques were used to analyze the surface topographies and chemicalcompositions. The coating exhibits superior anti-fouling and self-cleaning properties against various liquidand solid contaminants due to the synergic effect of low surface energy and hierarchical structures. The EIS and potentiodynamic polarization results show improved charge transfer resistance (Rct), positiveshifted corrosion potential (Ecorr), and decreased corrosion current density (Icorr), implying significantlyenhanced anti-corrosion performance with 99.83 % inhibition efficiency. Besides, the delay rate of icefreezingtime of the coating is 232 % at 5C, 137 % at 10 C and 204 % at 15 C compared withuncoated Q235 substrate respectively. The ice adhesion strength of the coating accounts for only6.55 % at 5C, 7.03 % at 10 C and 9.35 % at 15 C than that of the bare Q235 carbon steel, demonstratingultra-low ice adhesion force and anti-icing capabilities. The hygroscopic and deliquesce behaviorsof NaCl salt particles reveal an intriguing salt-deliquescence self-coalescence phenomenon andprospective anti-corrosion mechanism for superhydrophobic materials in high-humidity marine atmosphericenvironments.

Nepenthes pitcher-inspired lubricant-infused slippery surface with superior anti-corrosion durability, hot water repellency and scratch resistance

Binbin Zhang,Weichen Xu,Qingjun Zhu,Fang Guan,Yimeng Zhang 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.107 No.-

Nepenthes pitcher-inspired slippery surface provides an alternative strategy to overcome the shortcomingsof the current superhydrophobic surfaces such as thermal–mechanical stability and functional durability. Herein, we fabricate a lubricant-infused slippery surface (LISS) through micro-nano structurebuilding, low surface energy molecular grafting and perfluoropolyethers (PFPE) lubricant oil infusion. The surface morphologies, chemical compositions, wettability, dynamic liquids movement, selfcleaning,anti-corrosion behavior, and thermal–mechanical stability were investigated and analyzed. The electrochemical impedance spectroscopy (EIS) results reveal that the fabricated LISS exhibitsenhanced Rct and |Z|0.01Hz values with 2 orders of magnitude higher even after 30 days immersion,demonstrating outstanding long-lasting anti-corrosion properties. Besides, the LISS also exhibits superiorcapacities of hot water repellency (90 C water droplets) and scratching resistance. We believe theseresults have significant implications for understanding the design and multi-functional applications ofbiomimetic liquid-infused slippery materials.

An IGBT Open-Circuit Fault Detection Method for Modular Multilevel Converters

Binbin Li,Yi Zhang,Rongfeng Yang,Gaolin Wang,Dianguo Xu 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

Recently, the modular multilevel converter (MMC) has attracted increasing attentions due to its distinctive features, especially in the application of HVDC power transmission. One of the most significant characteristic of MMC is that it is composed of identical low-voltage submodules (SMs). As a result, the low-voltage IGBTs can be employed in each SM as the main power switch. However, since an MMC station usually contains hundreds of SMs, the IGBT becomes the most fragile component. In this paper, the failure characteristics of the IGBT open-circuit fault in a SM are firstly analyzed. Then, an observer-based IGBT open-circuit detection method is proposed, which can accurately detect the fault by comparing the estimated values with the actual sampled values. Finally, the validity and effectiveness of the proposed fault detection method are demonstrated by experimental results based on a single-phase MMC prototype in the laboratory.

Analysis of the Operating Principle and Parameter Design for the Modular Multilevel DC/DC Converter

Binbin Li,Shaolei Shi,Yibo Zhang,Rongfeng Yang,Gaolin Wang,Dianguo Xu 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

The modular multilevel converter (MMC) has become more and more attractive in the field of high-voltage high-power dc/ac power conversions. In the very recent years, the dc/dc modular multilevel converter is proposed intended for high-voltage dc/dc applications, such as the solid-state transformers and future dc-grid networks, which is extended from the traditional MMC. However, it remains unknown how to optimize the operation of this dc/dc modular multilevel converter and how to dimension the parameters of the elements in it. In this paper, a detailed analysis is performed to indentify the operating principle of the dc/dc modular multilevel converter. Using these analyses, the selection rules and parameter design method of the components are given to maximize the utilization ratio, improve the power density, and increase efficiency. Finally, the validity and effectiveness of this paper are verified by simulation results.

RESEARCH ON MARKET ORIENTATION, CHOICES OF PATENT STRATEGIES, AND THEIR OUTPUT EFFECT ON ALLIANCE FIRMS

Binbin Jiang,Honglei Liu,C. Anthony Di Benedetto,Gang Song 글로벌지식마케팅경영학회 2016 Global Marketing Conference Vol.2016 No.7

The increasing competition in recent years made more and more firms regard strategic alliance as an important alternative and solution to respond to fierce competition. As a kind of system arrangement among firms, the concept of strategic alliance was first proposed by Hopland and Nigel in the early 1980s, who defined strategic alliance as the collaboration mode in which two or more firms, aiming at joint-owned both market and resources, formed the kind of cooperation to enhance advantages, share risk or cost, and also mutual flow of production factors via different kinds of contracts or agreement. However, even before this definition, many firms have already begun their alliance strategies practices. As a cooperative form, strategic alliance, no matter its specific types, becomes one key choice for firms to acquire, maintain and enhance their market shares and positions. Shrader (2001) found that collaboration to foreign firms become key methods for newly-founded firms and small firms to enter foreign markets, which can bring these firms with suitable knowledge and market information, making these firms expand even faster with lower costs and market risks. The enhancing pace of globalization and internationalization triggered firms’ attentions to external markets, Archibugi and Iammarino (2002) found that fierce changes in internal market forced firms to expand their market and product scopes, making more and more firms realize product and R&D internationalization by searching, choosing and collaborating with foreign firms. Dong and Glaister (2006) found Chinese firms cared more about market positions, international expansion and technology exchanges, while foreign firms tended to enter to Chinese market and learn how to operate in China via strategic alliances. Although, many scholars brought out managerial practices of firms’ strategic alliances, and had already formed theoretical foundations, researches related to market orientation, especially how alliance firms establish and realize their strategic goals and performance goals under market motivation is still lack of studies. In reality, the mechanism how firms’ alliance intention transformed into their strategic or performance goals is still in the black box. Taken alliance firms as research objectives, this paper tends to explore how firms constructed strategic alliance due to market-orientation realize their strategic or performance goals via choice of patent strategies. We introduced patent strategies to establish the matching model, to analyze how firms market orientation influence choices of patent strategies, and their mutual effects on firms innovative performance, in hope to provide to the future studies and managerial practice how firms can choose the reasonable and effective alliance partners according to their own strategic and performance goals. Based on differentiation of market access and market extension motivation, we pointed out that, in order to realize the transformation from alliance motivation to innovation performance, alliance firms had to choose and determine among a set of practical and operational plans. Patent strategies, as a kind of operational plan, were conducive to transformation from alliance motivation to innovation performance. With the framework of market motivation, patent strategy and firms innovative performance, we put forward the hypotheses on how market motivation affect firms’ choices of patent strategies, and also the joint effects of market motivation and patent strategies on firm innovative performance. We selected alliance firms in IT industry as samples, with data from Cooperative Agreements and Technology Indicators Database, USPTO and R&D Scoreboard released by Department for Business, Innovation & Skills of UK, we empirically tested effects of market motivation on choices of patent strategies, and also effects of market motivation and patent strategies on firms innovative performance. Results showed that: different market positions led to differentiated motivations and patent strategies in their strategic alliances, firms with relatively weak market positions tend to pursue strategic profile of patent defensive and leveraging strategies under market access motivation, while firms with strong positions would like to implement patent proprietary and leveraging strategies in market extension motivation. The implementation of patent defensive and leveraging strategies under market access motivation enhanced innovation efficiency of the firms with weak market positions. Since these firms focused more on market positions and opportunities, their market capitalization tended to improve, but the motivation and utilization of patent strategies had no effect on patent output. Similar to these firms, the ones with stronger market position were inclined to strengthen their market opportunities and improve their market capitalization. Results indicated that because of their stronger market positions, these firms showed lower awareness of innovation efficiency and their emphasis on patent output was not high either, which then led to the fact that both market extension motivation and patent strategies used had no effects on firms innovative performance measured by innovation efficiency or patent output.

Modulation, Harmonic Analysis, and Balancing Control for a New Modular Multilevel Converter

Binbin Li,Yi Zhang,Gaolin Wang,Dianguo Xu 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.1

The modular multilevel converter (MMC) has been receiving increased attentions in recent years. The new modular multilevel converter is a derivative topology from the traditional MMC in which the number of sub-modules (SMs) necessitated by each phase can be reduced by one. This paper presents a phase-shifted carrier pulse-width modulation (PSC-PWM) for the new MMC with an optimal phase-shifted angle to suppress the harmonics of the output voltage. Further, the harmonic features when the capacitor voltage of the middle SM is selected as two different values are also investigated. Moreover, in order to avoid introducing an unnecessary dc offset current at the ac terminals of the new MMC, a novel capacitor voltage balancing scheme is proposed by adjusting the amplitude of the reference signals rather than the offset. Finally, the validity and effectiveness of the proposed modulation and balancing schemes have been verified by experimental results based on a three-phase prototype of the new MMC.