Placement of Parameter Server in Wide Area Network Topology for Geo-Distributed Machine Learning

li, yongyao,Fan, Chenyu,Zhang, Xiaoning,Chen, Yufeng 한국통신학회 2023 Journal of communications and networks Vol.25 No.3

Machine learning (ML) is extensively used in a widerange of real-world applications that require data all aroundworld to pursue high accuracy of a global model. Unfortunately,it is impossible to transmit all gathered raw data to a centraldata center for training due to data privacy, data sovereigntyand high communication cost. This brings the idea of geo-distributed machine learning (Geo-DML), which completes thetraining of the global ML model across multiple data centerswith the bottleneck of high communication cost over the limitedwide area networks (WAN) bandwidth. In this paper, we studyon the problem of parameter server (PS) placement in PSarchitecture for communication efficiency of Geo-DML. Ouroptimization aims to select an appropriate data center as thePS for global training algorithm based on the communicationcost. We prove the PS placement problem is NP-hard. Further,we develop an approximation algorithm to solve the problemusing the randomized rounding method. In order to validate theperformance of our proposed algorithm, we conduct large-scalesimulations, and the simulation results on two typical carriernetwork topologies show that our proposed algorithm can reducethe communication cost up to 61.78% over B4 topology and21.78% over Internet2 network topology.

Female migrants in China: Second child fertility behavior and employment stability

Li Hu,Dong Chenyu,Wang Xiaofeng 이화여자대학교 아시아여성학센터 2022 Asian Journal of Women's Studies(AJWS) Vol.28 No.1

Researchers have found a negative relationship between female fertility and employment. China’s floating population comprises 244 million as of 2017. This migrant population has relevance in view of China’s hukou (household registration) system, with the proportion of females increasing annually. This study is grounded in social role theory and employs the 2016 China Migrants Dynamic Survey (CMDS) to examine the impact of second child fertility behavior on the employment stability of female migrants in China, with respect to urban and rural differences. Binary logistic regression results indicate that bearing second children negatively affects the employment stability of female migrants. Also, its impact is stronger for female migrants of urban origin than their rural counterparts. In addition, family migration is noted to mitigate the conflict between childbearing and employment stability for them as they continue to face the dilemma of having children or seeking employment stability, especially if family and social support is weak or absent. We discuss the implications of this study on policy changes to alleviate the conflict female migrants experience in choosing between fertility and employment.

A Brief Analysis of The Evolution of Values of Chinese and Korean Animated Film Characters

Ju li,Jing Chenyu 한중경제문화학회 2021 한중경제문화연구 Vol.17 No.-

The hypothetical cuticular protein, CPH19, is involved in cuticle formation during molt of silkworm Bombyx mori

Zhao Chenyue,Huang Qunxia,Qian Yuxin,Zhao Xuhui,Guo Shigang,Kan Yunchao,Li Dandan 한국응용곤충학회 2023 Journal of Asia-Pacific Entomology Vol.26 No.3

The cuticle supports the insect body and serves as a protective barrier against pathogens and pesticides. We found that the gene CPH19, encoding the hypothetical cuticular protein 19 (CPH19) of the silkworm Bombyx mori, was highly expressed in the cuticle during larval molt. Injection of CPH19 double-stranded RNA (dsRNA) into the hemolymph of 2-day-old third instar larvae (2dLa3) accelerated insect molting at the La3-La4 and La4-La5 transitions. Nevertheless, the larvae injected with CPH19 dsRNA had difficulty shedding their cuticle and suffered from molt defects, and their exuviae were larger and heavier than those of the control group. Morphological comparison of the exuviae between CPH19 dsRNA-injected and control larvae showed that the exocuticle-endocuticle layer was thicker in the former. The effect of CPH19 dsRNA injection on gene expression was further investigated by quantitative real-time polymerase-chain reaction (qRT-PCR). Surprisingly, the mRNA levels of CPH19 and other CP genes such as CPH18, CPH20, CPR69, CPR96, CPR97, CPR98 and CPR100, as well as chitinase genes such as chs-2 and chsA, were significantly increased in the CPH19 dsRNA-injected insects compared to the control. Bioinformatic predictions and luciferase assay analyses identified a proximal promoter near the transcription start site of CPH19 with strong transcriptional activity that may be involved in an RNAbased promoter targeting mechanism mediated by small activating RNAs (saRNAs). Treatment with the insec ticide decamethrin revealed that CPH19 dsRNA-injected larvae were more resistant to insecticides than control larvae, which could be exploited for the development of new pest control strategies.

Tribological Properties of PAO40@SiO2/UHMWPE Composites Subjected to Heavy-loading Conditions

Yao Chenyu,Jia Dan,Wan Changxin,Li Jian,Zhan Shengpeng,Yang Tian,Qi Xiaowen,Liu Changxin,Duan Haitao 한국고분자학회 2022 폴리머 Vol.46 No.5

In the present study, the ballistic impact resistance of kevlar reinforced polymer composites and shape memoryalloy sheet reinforced kevlar epoxy polymer composites have been compared numerically and experimentally. The testspecimens have been fabricated by the hand layup method, and the ballistic impact test has been conducted accordingto NIJ Level IIIA. In the current research, a new method has been proposed to measure the ballistic impact resistanceof the material by using Image J software. From the test results, it has been observed that reinforcement of shape memoryalloy in kevlar epoxy polymer composites has increased the ballistic impact resistance by 89-145% for the damaged areacompared with plain kevlar reinforced epoxy polymer composite. Also, the damaged area observed in the numerical andthe experimental results is almost the same.

信阳小调初探

王晨雨(Chenyu Wang),李艳慧(Yanhui Li) YIXIN 출판사 2023 Journal of China Studies Vol.1 No.3

信阳位于长江、淮河流域之间,是南北方文化交融的中心地带。其民歌种类繁多,分布广泛,商城县、新县、固始县、罗山县、息县、光山县、潢川县、淮滨县均有分布,其中以信阳小调最为丰富。信阳小调分为吟唱调、谣曲和时调三类,题材大多来源于人民群众的劳动生产,风俗习惯,现实生活,婚姻爱情等,有的反映了旧社会底层人民的悲惨生活,有的反映了民俗节日,有的具有较强的时代特征。以“装饰音”“节奏多变”“级进和三度跳进”“重复乐句”为基础形成的典型的旋律构成类型,使信阳小调拥有了独有的特色。 Xinyang is located between the Yangtze River and Huai River basins, and is the center of cultural integration between the north and south. Its folk songs have a wide variety and are widely distributed (including Shangcheng County, Xinxian County, Gushi County, Luoshan County, Xi County, Guangshan County, Huangchuan County, and Huaibin County), with Xinyang minor being the most abundant. Xinyang minor tunes are divided into three categories: singing tunes, folk songs, and seasonal tunes. The themes mostly come from the labor and production of the people, customs and habits, real life, love and marriage, etc. Some reflect the tragic life of the lower-class people in the old society, some reflect folk festivals, and some have strong characteristics of the times. The typical melodic composition types based on ‘decorative tone’, ‘variable rhythm’, ‘progressive and triple jump’, and ‘repetitive phrases’ give Xinyang minor unique characteristics.

Security Analysis of the Khudra Lightweight Cryptosystem in the Vehicular Ad-hoc Networks

( Wei Li ),( Chenyu Ge ),( Dawu Gu ),( Linfeng Liao ),( Zhiyong Gao ),( Xiujin Shi ),( Ting Lu ),( Ya Liu ),( Zhiqiang Liu ) 한국인터넷정보학회 2018 KSII Transactions on Internet and Information Syst Vol.12 No.7

With the enlargement of wireless technology, vehicular ad-hoc networks (VANETs) are rising as a hopeful way to realize smart cities and address a lot of vital transportation problems such as road security, convenience, and efficiency. To achieve data confidentiality, integrity and authentication applying lightweight cryptosystems is widely recognized as a rather efficient approach for the VANETs. The Khudra cipher is such a lightweight cryptosystem with a typical Generalized Feistel Network, and supports 80-bit secret key. Up to now, little research of fault analysis has been devoted to attacking Khudra. On the basis of the single nibble-oriented fault model, we propose a differential fault analysis on Khudra. The attack can recover its 80-bit secret key by introducing only 2 faults. The results in this study will provides vital references for the security evaluations of other lightweight ciphers in the VANETs.

Security Analysis of the Whirlpool Hash Function in the Cloud of Things

( Wei Li ),( Zhiyong Gao ),( Dawu Gu ),( Chenyu Ge ),( Linfeng Liao ),( Zhihong Zhou ),( Ya Liu ),( Zhiqiang Liu ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.1

With the advancement and deployment of leading-edge telecommunication technologies for sensing and collecting, computing related information, Cloud of Things (CoTs) has emerged as a typical application platform that is envisioned to revolutionize the daily activities of human society, such as intelligent transportation, modern logistics, food safety, environmental monitoring, etc. To avoid any possible malicious attack and resource abuse, employing hash functions is widely recognized as one of the most effective approaches for CoTs to achieve message integrity and data authentication. The Whirlpool hash function has served as part of the joint ISO/IEC 10118-3 International Standard by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). In this paper, we propose an effective differential fault analysis on Whirlpool in the byte-oriented random fault model. The mathematical analysis and experimental results show that 8 random faults on average are required to obtain the current 512-bit message input of whirlpool and the secret key of HMAC-Whirlpool. Our work demonstrates that Whirlpool and HMAC-Whirlpool are both vulnerable to the single byte differential fault analysis. It provides a new reference for the security analysis of the same structure of the hash functions in the CoTs.

Security Analysis of the PHOTON Lightweight Cryptosystem in the Wireless Body Area Network

( Wei Li ),( Linfeng Liao ),( Dawu Gu ),( Chenyu Ge ),( Zhiyong Gao ),( Zhihong Zhou ),( Zheng Guo ),( Ya Liu ),( Zhiqiang Liu ) 한국인터넷정보학회 2018 KSII Transactions on Internet and Information Syst Vol.12 No.1

With the advancement and deployment of wireless communication techniques, wireless body area network (WBAN) has emerged as a promising approach for e-healthcare that collects the data of vital body parameters and movements for sensing and communicating wearable or implantable healthful related information. In order to avoid any possible rancorous attacks and resource abuse, employing lightweight ciphers is most effective to implement encryption, decryption, message authentication and digital signature for security of WBAN. As a typical lightweight cryptosystem with an extended sponge function framework, the PHOTON family is flexible to provide security for the RFID and other highly-constrained devices. In this paper, we propose a differential fault analysis to break three flavors of the PHOTON family successfully. The mathematical analysis and simulating experimental results show that 33, 69 and 86 random faults in average are required to recover each message input for PHOTON-80 /20/16, PHOTON-160/36/36 and PHOTON-224/32/32, respectively. It is the first result of breaking PHOTON with the differential fault analysis. It provides a new reference for the security analysis of the same structure of the lightweight hash functions in the WBAN.

Auto-parametric resonance of framed structures under periodic excitations

Yuchun Li,Hongliang Gou,Long Zhang,Chenyu Chang 국제구조공학회 2017 Structural Engineering and Mechanics, An Int'l Jou Vol.61 No.4

A framed structure may be composed of two sub-structures, which are linked by a hinged joint. One sub-structure is the primary system and the other is the secondary system. The primary system, which is subjected to the periodic external load, can give rise to an auto-parametric resonance of the second system. Considering the geometric-stiffness effect produced by the axially internal force, the element equation of motion is derived by the extended Hamilton\'s principle. The element equations are then assembled into the global non-homogeneous Mathieu-Hill equations. The Newmark\'s method is introduced to solve the time-history responses of the non-homogeneous Mathieu-Hill equations. The energy-growth exponent/coefficient (EGE/EGC) and a finite-time Lyapunov exponent (FLE) are proposed for determining the auto-parametric instability boundaries of the structural system. The auto-parametric instabilities are numerically analyzed for the two frames. The influence of relative stiffness between the primary and secondary systems on the auto-parametric instability boundaries is investigated. A phenomenon of the \"auto-parametric internal resonance\" (the auto-parametric resonance of the second system induced by a normal resonance of the primary system) is predicted through the two numerical examples. The risk of auto-parametric internal resonance is emphasized. An auto-parametric resonance experiment of a