Effect of P3HT passivation layer on triple cation organic-inorganic hybrid perovskite memristor

Wang Yucheng,Xiong Yuxuan,Wang Hongsu,Wu Xiang,Sha Jian,Shang Yueyang,Zhang Yongqi,Li Wei,Wang Shaoxi 한국물리학회 2023 Current Applied Physics Vol.47 No.-

Triple cation organic-inorganic hybrid perovskite (TCP) memristor is a novel candidate for artificial visual applications due to the integrating of recognition, storage, and computing. However, concerns remain regarding the moisture-induced degradation and thermal stability. Here, P3HT was deposited on the TCP film to optimize the memristor performance which showed better film surface quality and lower power consumption. When the thickness of the P3HT layer increases, the grain boundary of the TCP film was gradually filled, leading to the inhibition of the ions/vacancies drifting, and thus the device type was changed from digital to analog. Besides, various functions are demonstrated in TCP photoelectric memristor including excitatory postsynaptic current under optic and electric stimulations and spike rate-dependent plasticity, proving the great application prospects in numerical calculation and information perception.

A Study of Leveraging Memory Level Parallelism for DRAM System on Multi-Core Architecture

Yuxuan Wang,Yingping Zhang,Xiaotian Zhang,Jian Yin,Licheng Chen 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.4

DRAM system has been more and more critical on modern multi-core architecture where the Moore’s law has been made effect on increasing the number of cores integrated in a processor chip. The performance of DRAM system is usually measured in term of bandwidth and latency, which are regarded as inherently depending on Row Buffer Hit Rate (RBHR) according to previous studies. In this paper, we find that Memory Level Parallelism (MLP) exhibits a stronger correlation with the performance of DRAM system on multi-core/many-core architecture than RBHR, and promoting MLP significantly improves DRAM system performance. In order to exploit the MLP, we have evaluated various approaches including multi-bank, multi-row-buffers, multi-memory-controllers and the obsolete Virtual Channel Memory (VCM). The experimental results show that VCM is a better alternative to traditional DRAM chip on multicore/many-core architecture than the other three approaches because VCM has almost all the advantages of the others: 1) it can improve homogeneous workloads’ IPC by 2.21X on a 16-core system with 32 virtual channels due to leveraging unexploited MLP. 2) It can also promote Quality-of-Service (QoS) of DRAM system by removing unfairness while memory controllers serve memory requests. 3) It can save energy and has low area costs. Unfortunately, VCM, which was proposed in the late 1990s, faded away before multi-core/manycore became dominated. Therefore, we suggest memory chip vendors reconsider the VCM technology for multi-core architecture.

Dual-Phase Shifting Strategy for CLLC Resonant Converters

Wang Dangshu,Zhao Licong,Chang Menghu,Yang Yuxuan,Guan Zhimin,Zhang Ruchuan,Wang Xinxia 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.4

The CLLC resonant converter has the advantages of bidirectional power transmission, natural soft switching, and wide range voltage output. However, the gain curve is relatively smooth during high-frequency light-load operation, and it is diffi cult to adjust through frequency conversion; the traditional fundamental harmonic approximation (FHA) method has a large error in calculating the gain at a position away from the resonance point, which brings diffi culties to the design. In order to better design the converter, this paper proposes a dual phase-shift (DPS) control method based on time-domain analysis, which can achieve a wide voltage range output without losing soft switching, and has constant current source output characteristics. Firstly, the time-domain model of the CLLC converter is analyzed, and the output voltage gain and soft switching range under DPS control are solved; then a simulation is built for verifi cation; fi nally, a 200/80 V, rated power 500 W full-bridge CLLC resonant converter experimental prototype is built. The experimental results prove that the converter has good soft switching range and constant current source output characteristics.

Causal Relationship between the regional economic growth and the air cargo increase in China

Yuxuan Wang,김태승 피터드러커 소사이어티 2022 창조와 혁신 Vol.15 No.4

The purpose of this paper is to analyze the Granger causal relationship between the increase of air freight and economic growth in China. In particular, this paper tried to check what kind of causality appears depending on the geographical and industrial characteristics of the region, and economic size. For this purpose, this paper collected panel data for 20 years from 2000 to 2019 for 31 provinces in China, which are in total 620 observations. The methodology used for the analysis is the VECM method on each sub-group after going through the normal stationary test and the cointegration test. The conclusions of this paper are as follows. First, China has a bidirectional causal relationship between its economy and air freight at the national level. Second, geographically, a bidirectional causal relationship is shown in the Central region and, economically, in the middle-size region, but in advanced regions such as Bohai bay and Yangtze river, a Granger-causal relationship is shown in the direction from economic growth to air freight increase. This shows that the southeastern provinces of China have already entered the stage of economic maturity. Third, the Pearl River Delta and the Dongbei region show a causal relationship in the direction from air freight to economic growth. This can be said to reflect the geographical characteristics of each region and the level of economic growth in China.

원작기반 동서양 판타지 게임 캐릭터의 채색 이미지 표현에 대한 비교 분석

왕우선 ( Wang Yuxuan ),백철호 ( Paik Paul Chul-ho ) 디자인융복합학회 2017 디자인융복합연구 Vol.16 No.3

RPG 게임 산업의 발달로 다양한 게임이 개발되면서 그 중에서도 소설에 기원을 두고 유사 배경과 캐릭터들이 등장하는 판타지게임이 많아졌다. 그러나 기원은 같으나 이를 기반으로 만들어진 게임은 동서양이 각각 표현 방식에 큰 차이점을 보이고 있다. 따라서 동서양의 판타지 게임 캐릭터 디자인에 대한 연구 필요성이 제기된다 하겠다. 본 연구는 게임 세계관 구성 중 종족 디자인을 중심으로, 대표적인 판타지 소설 `반지의 제왕`의 엘프를 모델로 한 서양의 판타지 게임 `월드 오브 워크래프트(World of Warcarft)`와 동양의 판타지 게임 `테라(Tera)`에 등장하는 엘프의 시각적인 디자인 중 복식의 배색을 IRI 배색 이미지 스케일을 통해 플레이어의 공통적 체험을 비교 분석하였다. 종족에 형성된 역사나 문화의 분석을 통해서 동서양 판타지 세계관 중 엘프 이미지의 차이와, 변하지 않는 핵심적이며 상징적 특징을 탐구하였다. 또한 이를 통해 세계관 구성 중 색상을 이용해 종족 특징을 시각적인 디자인으로 표현하는 방식에 대해 연구하였다. 연구 결과 테라는 자연적이며 우아한 심리적 감성을 표현하는 색을 활용하며 미를 강조하는 반면 WOW는 색을 통해서 종족 간의 차이점을 표현하면서 인간처럼 일반적인 종족 이미지를 제시하는 특징이 있다. 이로써 동서양 판타지 게임의 캐릭터 이미지 표현을 통한 세계관의 차이를 확인할 수 있다. As RPG games have become more popular and diverse in recent years that need to study a unique game ethnic design. This study focuses on the ethnic design of the game world, centered on the fantasy novel - the Lord the Rings. It based on the elf`s visual design of the Western fantasy game World of Warcraft, and the Asian fantasy game Tera is compared based on the IRI color image scale. Through the analysis of ethnically formed history and culture, it explores the difference between the design of the East and the West fantasy world view and the key symbolic characteristic which does not change. Through this study to find how to use color in world view composition and express racial characteristics with visual design. The results of the survey show that images of WOW and Tera Elves may differ. Tera utilizes colors that express natural, elegant psychological emotions. Contrary to the emphasis on beauty, WOW represents the difference between ethnic groups in color and presents the image as a general race like a human being. This result shows that there are differences in the image of the Elves among the fantasy games of the East and the West.

Transcriptomic profiling of the cold stress and recovery responsiveness of two contrasting Guizhou HE rice genotypes

Wang Zhongni,Wu Xian,Chen Yuxuan,Wu Chaoxin,Long Wuhua,Zhu Susong 한국유전학회 2023 Genes & Genomics Vol.45 No.4

Background At the seed germination stage, rice is sensitive to cold stress, which adversely affects its growth and development. Guizhou HE rice comprises several different landraces, most of which are cold tolerant. Objective To identify differentially expressed genes and molecular mechanism underlying the cold tolerance of Guizhou HE. Methods Two Guizhou HE genotypes, AC44 (cold-sensitive) and AC96 (cold-tolerant), which exhibit opposite phenotypes in response to cold treatment at the seed germination stage were used. Comprehensive gene expressions of AC44 and AC96 under 4 °C cold treatment and subsequent recovery conditions were comparatively analyzed by RNA sequencing. Results Overall, 11,082 and 7749 differentially expressed genes were detected in AC44 and AC96, respectively. Comparative transcriptome analysis demonstrated that, compared with AC44, AC96 presented fewer upregulated and downregulated genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses demonstrated that AC96 presented more upregulated GO terms, especially terms associated with biological processes. However, AC44 presented more terms related to cellular components, mainly chloroplasts. Moreover, DEGs related to the auxin signaling pathway (including ARF and IAA family members) and transcription factors (including members of the F-box, bZIP, basic helix-loop-helix [bHLH], and MYB-like transcription factor families) were found to be expressed specifically in AC96; thus, these DEGs may be responsible for the cold tolerance of AC96. Conclusions These findings present information about the cold tolerance mechanism of Guizhou HE rice at the germination stage, providing valuable resources and candidate genes for breeding cold-tolerant rice genotypes.

An Enhanced Video Anomaly Detection System for Smart City Management

Yuechun Wang,Shufei Zhu,Yuxuan Zhao,Jie Zhang,Ka Lok Man 한국ITS학회 2022 한국ITS학회 학술대회 Vol.2022 No.06

Since the popularity of city monitoring systems has increased, surveillance videos have become more common. However, due to the massive increment of social event needs after lifting the coronavirus pandemic lockdown, the pressure of handling anomalies on government departments is growing with each passing day. In addition, surveillance cameras cannot record every corner of our city. There are still blind areas such as indoor environments and remote regions. Therefore, this paper introduces and develops an comprehensive system for video anomaly detection in smart city management, which is based on mobile phones, to enlarge the coverage of the current surveillance system. This system can capture and transmit abnormal videos. In addition, a deep learning method (VGG16) is implemented in the system to do video anomaly detection.

Designing Ternary Laves Phase-Based Eutectic Alloys CrFeNbx with Excellent Strength, Toughness, and Thermal Stability

Yunlong Xue,Yuxuan Wang,Haohua Sun,Na Feng,Liang Yuan 대한금속·재료학회 2023 METALS AND MATERIALS International Vol.29 No.2

Three ternary Laves phase-based eutectic alloys CrFeNbx(x = 2.0, 2.35, 2.7) were designed successfully by combining thebinary phase diagrams and thermodynamics calculations. With the increasing Nb content, the solidified microstructuresevolved from the primary (Cr, Fe)2Nb plus the eutectic (Cr, Fe)2Nb/Nbss in the CrFeNb2.0,via the full eutectic (Cr, Fe)2Nb/Nbss in the CrFeNb2.35,and finally to the primary Nbss plus the eutectic (Cr, Fe)2Nb/Nbss in the CrFeNb2.7. The full eutectic(Cr, Fe)2Nb/Nbss of the CrFeNb2.35was found with outstanding thermal stability, and the lamellar eutectic was quitestable even under the heat-treatment of 1273 K/48 h. The compression strength and fracture toughness increased firstly anddecreased subsequently with the increase of Nb content, which reached their maximums of 2.54 GPa and 18.25 MPa·m1/2,respectively, in the CrFeNb2.35. The excellent combination of compression strength and fracture toughness in the CrFeNbx(x = 2.0, 2.35, 2.7) were attributed to the synergistic effects of Laves phase strengthening, interface strengthening, solidsolution strengthening, alloying toughening and Nbss phase toughening mechanisms.

Multi-mode energy management method of integrated photovoltaic energy storage system

Zhichong Shao,Yuxuan Bi,Bin Liang,Houji Li,Yong Wang 전력전자학회 2023 ICPE(ISPE)논문집 Vol.2023 No.-

This paper presents a single-phase power conversion system (PCS) consisting of photovoltaic part, battery storage part and inverter part. The topology contains a full-bridge LLC converter and a bidirectional buck-boost for storage interface, a boost converter for PV interface and a HERIC inverter for grid interface. This article innovatively designs three modes to handle different kinds of operating state. Mode1 and Mode3 corresponds to the off-grid state while Mode2 corresponds to the on-grid state. The droop control method in the storage interface, a double closed loop control method in the invertor interface and a voltage loop control method in the PV interface are adopted in this system respectively. Multi-mode energy management has significant advantages in high efficiency and reliability. An experimental prototype of this system is built to verify the feasibility of the system structure and mode switching strategy.

Optimized interfacial compatibility of carbon fiber and epoxy resin via controllable thickness and activated ingredients of polydopamine layer

Wu Dongliang,Xing Yuxuan,Zhang Denglu,Hao Zhenna,Dong Qi,Han Yongqin,Liu Lei,Wang Maoju,Zhang Ruliang 한국탄소학회 2024 Carbon Letters Vol.34 No.1

In this work, the trend in the performance of carbon fiber (CF) and its composite during self-polymerization of polydopamine (PDA) at carbon fiber surface was investigated by varying the self-polymerization time of dopamine in an aqueous solution. Research has shown that the PDA coating elevated the surface roughness and polarity of the inert fiber. The tensile strength of single carbon fiber was significantly improved, especially after 9 h of polydopamine self-polymerization, increasing by 18.64% compared with that of desized carbon fiber. Moreover, the interlaminar shear strength (ILSS) of CF-PDA9-based composites was 35.06% higher than that of desized CF-based composites. This research will provide a deep insight into the thickness and activated ingredients of dopamine oxidation and self-polymerization on interfacial compatibility of carbon fiber/epoxy resin composites.