Is the Fano Antiresonance a Necessary Requirement for Circulating Currents in Mesoscopic Interferometers?

Yao Heng Su,Sam Young Cho,Ai Min Chen,Taeseung Choi 한국물리학회 2010 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.57 No.1

Coherent quantum tunneling effects on quantum interference are investigated in electron transport through a mesoscopic interferometer. An evanescent wave tunneling through a potential barrier in one arm can interfere with a propagating wave passing through the other arm of the interferometer. It is shown that, even for the same arm lengths, such a quantum interference can induce a circulating current, where Fano antiresonances do not occur in electron transmission. It is found that there exists a critical value of asymmetric arm lengths that gives rise to a Fano antiresonance in electron transmission for quantum interference between evanescent and propagating waves. We discuss the effects of Fano antiresonances originating from asymmetric arm lengths on circulating currents.

Sphingomonas morindae sp. nov., isolated from Noni (Morinda citrifolia L.) branch

Yao, Su,Ge, Yuanyuan,Zhai, Lei,Liu, Yang,Su, Jiaojiao,Cao, Yanhua,Cheng, Chi,Kim, Song-Gun,Lee, Yong-Jae,Zhang, Xin Microbiology Society 2015 International journal of systematic and evolutiona Vol.65 No.9

Big Data Analysis: Innovation of College English Writing Teaching: A Quantitative Research on “One Million Essays on Same Topics” English Writing Activity

Su Yao 아시아사회과학학회 2021 International Science Research Vol.1 No.1

Guided by the College English Curriculum Requirements ( published by National Foreign Languages Teaching Advisory Board in the Ministry of Education),this the paper aims at exploring methods to improve college English writing teaching based on data analysis. This paper uses the most popular automated essay scoring system and sentence correcting platform in China to launch a case study. Authors of this paper made quantitative research and data analysis on essays submitted in “One Million Essays on Same Topics” English Writing Activity, then summarized students’ writing characteristics and their shortcomings. Finally, authors of this paper provided suggestions on effective data-driven precise teaching model to improve college English writing teaching.

Fano-Andreev Transport and Circulating Currents in Mesoscopic Interferometers

Yao Heng Su,Sam Young Cho 한국물리학회 2012 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.61 No.3

Quantum correlation and interference effects are investigated in mesoscopic interferometers connected to a normal metal and a superconductor. For quasiparticle excitation energies smaller than superconducting gap, a Fano-Andreev antiresonance for zero excitation energy is shown to be split into two zero-transmissions located at energies lower and higher than the Fano-Andreev antiresonance energy. For an excitation energy bigger than the gap, the higher energy antiresonance disappears for electron-like quasiparticle transport. In the presence of a superconductor interface potential <i>Z</i>, we find that the transport and the circulating currents normalized by their amplitudes for a clean interface have the same <i>I</i>(<i>Z</i>)-<i>Z</i> curve. We discuss a transition among the three types of normalized currents, which shows a characteristic transition diagram in association with the excitation energy. Also, as a demonstration of the existence of Andreev holes, we show that only the Andreev hole current can circulate along the interferometer loop.

Simulation study on the tunnel networks of subterranean termites and the foraging behavior

이상희,Nan-Yao Su 한국응용곤충학회 2010 Journal of Asia-Pacific Entomology Vol.13 No.2

Most subterranean termites forage for food by creating tunnel galleries underground. These tunnel networks reflect a compromise between foraging efficiency and other environmental constraints, such as soil hardness and moisture content. Thus, understanding tunnel networks is important for understanding foraging behavior. Due to the difficulties in direct observation of tunneling patterns in the field, we used a theoretical approach for this analysis. We first constructed a lattice model to simulate the tunnel networks of Coptotermes formosanus Shiraki and Reticulitermes flavipes (Kollar) on the basis of the experimental data provided by Su et al. (Su, N.-Y., Stith, B.M., Puche, H., Bardunias, P., 2004. Characterization of tunneling geometry of subterranean termites (Isoptera: Rhinotermitidae) by computer simulation. Sociobiology 44 (3), 471–483.). Using this model and two of its modified versions, we explored the relationship between the food encounter rate and food distributions and analyzed how this relationship is influenced by changes in the tunnel characteristic constituents, such as the branching tunnel length and frequency. Additionally, we investigated the effects of landscape heterogeneity on the foraging efficiency. In the discussion, we briefly introduced our novel individual-based model comprising individual termites and their surroundings, and we addressed the necessity of this model in the functioning of the network and the formation of the network in relation to foraging behavior.

CGS 치환율 및 프리믹스 시멘트 종류에 따른 콘크리트의 응결시간 특성

김수호(Kim, Su-Hoo),후윈야오(Hu, Yun-Yao),임군수(Lim, Gun-Su),윤치환(Yoon, Chee-Hwan),김종(Kim, Jong),한민철(Han, Min-Cheol) 대한건축학회 2021 대한건축학회 학술발표대회 논문집 Vol.41 No.2

In this study, compressive strength and setting time properties of concrete depending on the presence or absence of premix cement and CGS were analyzed as part of a study on the development of hydration heat reduction method through upper and lower mixing of mass concrete. As a result, the upper mix is the best in the two levels of premix-type cement ESC and SESC, and the lower mix is considered the most effective to apply TBC and CGS replacement concrete.

Simulation study on the tunnel networks of subterranean termites and the foraging behavior

Lee, Sang-Hee,Su, Nan-Yao 한국응용곤충학회 2010 Journal of Asia-Pacific Entomology Vol.6 No.2

Most subterranean termites forage for food by creating tunnel galleries underground. These tunnel networks reflect a compromise between foraging efficiency and other environmental constraints, such as soil hardness and moisture content. Thus, understanding tunnel networks is important for understanding foraging behavior. Due to the difficulties in direct observation of tunneling patterns in the field, we used a theoretical approach for this analysis. We first constructed a lattice model to simulate the tunnel networks of Coptotermes formosanus Shiraki and Reticulitermes flavipes (Kollar) on the basis of the experimental data provided by Su et al. (Su, N.-Y., Stith, B.M., Puche, H., Bardunias, P., 2004. Characterization of tunneling geometry of subterranean termites (Isoptera: Rhinotermitidae) by computer simulation. Sociobiology 44 (3), 471-483.). Using this model and two of its modified versions, we explored the relationship between the food encounter rate and food distributions and analyzed how this relationship is influenced by changes in the tunnel characteristic constituents, such as the branching tunnel length and frequency. Additionally, we investigated the effects of landscape heterogeneity on the foraging efficiency. In the discussion, we briefly introduced our novel individual-based model comprising individual termites and their surroundings, and we addressed the necessity of this model in the functioning of the network and the formation of the network in relation to foraging behavior.

Behavioral Response of Termites to Tunnel Surface Irregularity

Sang-Hee Lee,Rou-Ling Yang,Nan-Yao Su 한국응용곤충학회 2009 한국응용곤충학회 학술대회논문집 Vol.2009 No.05

Subterranean termites construct underground tunnels, tens to hundreds of meters in length, in order to search for and transport resources. Diverse soil conditions surrounding the tunnels, such as soil pores and differing moisture concentrations, may cause different sized- and shaped-irregularities in the tunnels. To understand how individual termites respond to the irregularities, the present study monitored the movement of termites, Coptotermes formosanus Shiraki, in artificially excavated tunnels with rectangular irregularities of varying sizes in twodimensional sand substrates. Termites tunneled at some of the irregularities and not at the others. The tunneling or non-tunneling behavior resulted from four different responses. The non-tunneling response may result from a behavioral adaptation that allows termites to avoid wasting energy that may be used in foraging.

Behavioral Response of Termites to Tunnel Intersection

Sook Jung Ku,Sheon-Young Kang,Nan-Yao Su,Sang-Hee Lee 한국응용곤충학회 2009 한국응용곤충학회 학술대회논문집 Vol.2009 No.05

Subterranean termites construct complicated tunnel network for foraging below the ground. Thus, they often encounter a number of tunnel intersections during their moving from place to place in the network. In order to understand how termites respond to the intersections, we artificially excavated two tunnels intersected with 90° degree in soil-filled arenas. The two tunnels had the width of W1 and W2 (=2, 3, and 4mm), respectively. We systematically observed the response behavior of advancing termites to the intersection with the combination of W1 and W2, (W1, W2). For (W1, W2)=(2, 2) and (3, 3), the advancing termites passed the intersection without directional changes because it was difficult for termites to bend their body to change their moving direction due to the small-sized width. For (W1, W2)=(4, 4), the termites statistically-equally chose the three directions, left, right, and straight, which was due to the fact that the intersection provided enough space for termites to bend. For (W1, W2)=(2, 3), (2, 4), and (3, 4), termites, advancing in narrower tunnels, tended considerably to turn right or left, while termites, advancing in wider tunnels, were favorably inclined to go straight. These results can be understood by considering the relationship between termite body length and tunnel width as explained for the cases of W1=W2. In addition, we briefly discussed our findings in relation to termite foraging efficiency.

Direct Adaptive Fuzzy Sliding Mode Control for Under-actuated Uncertain Systems

Su, Shun-Feng,Hsueh, Yao-Chu,Tseng, Cio-Ping,Chen, Song-Shyong,Lin, Yu-San Korean Institute of Intelligent Systems 2015 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.15 No.4

The development of the control algorithms for under-actuated systems is important. Decoupled sliding mode control has been successfully employed to control under-actuated systems in a decoupling manner with the use of sliding mode control. However, in such a control scheme, the system functions must be known. If there are uncertainties in those functions, the control performance may not be satisfactory.In this paper, the direct adaptive fuzzy sliding mode control is employed to control a class of under-actuated uncertain systems which can be regarded as a combination of several subsystems with one same control input. By using the hierarchical sliding control approach, a sliding control law is derived so as to make every subsystem stabilized at the same time. But, since the system considered is assumed to be uncertain, the sliding control law cannot be readily facilitated. Therefore, in the study, based on Lyapunov stable theory a fuzzy compensator is proposed to approximate the uncertain part of the sliding control law. From those simulations, it can be concluded that the proposed compensator can indeed cope with system uncertainties. Besides, it can be found that the proposed compensator also provide good robustness properties.