Issue Special Issue 6/2019
Content (243 Articles)
Turning strategy of snake-like robot based on serpenoid curve under cloud assisted smart conditions
Chao Wang, Yanbin Peng, Dongfang Li, Zhenhua Pan, Hongbin Deng, Dongguang Li, Bin Li
Channel assignment based coding mechanism for reliable transmission for smart cities
Ramkumar Jayaraman, Gunasekaran Raja
Adaptive PID controller for cloud smart city system stability control based on chaotic neural network
Xuebiao Zhu, Kuisheng Chen, Yanan Wang, Huasheng Zheng
A novel cluster computing technique based on signal clustering and analytic hierarchy model using hadoop
Wenzhun Huang, Haoxiang Wang, Yucheng Zhang, Shanwen Zhang
Novel effective X-path particle swarm optimization based deprived video data retrieval for smart city
S. Thanga Ramya, Bhuvaneshwari Arunagiri, P. Rangarajan
A hybrid cluster head selection model for Internet of Things
M. Praveen Kumar Reddy, M. Rajasekhara Babu
An intelligent hybrid model for power flow optimization in the cloud-IOT electrical distribution network
Yantian Zhang, Haoxiang Wang, Yanzhao Xie
Enhanced secure sharing of PHR’s in cloud using user usage based attribute based encryption and signature with keyword search
M. Lilly Florence, Dhina Suresh
An efficient city energy management system with secure routing communication using WSN
M. Kavitha, B. G. Geetha
Design and implementation of an efficient multi cloud storage approach for resource constrained mobile devices
Rajeev Kumar Bedi, Jaswinder Singh, Sunil Kumar Gupta
The generic technology identification of saline–alkali land management and improvement based on social network analysis
Li Liu, Xiuguang Bai, Zhide Jiang
RETRACTED ARTICLE: A scheme for detecting outliers using sequential adjacency among entities
V. Kathiresan, N. A. Vasanthi
Improved elliptical curve cryptography and Abelian group theory to resolve linear system problem in sensor-cloud cluster computing
N. Thangarasu, A. Arul Lawrence Selvakumar
TCACWCA: transmission and collusion aware clustering with enhanced weight clustering algorithm for mobile ad hoc networks
T. Maragatham, S. Karthik, R. M. Bhavadharini
Internet of Things network cognition and traffic management system
Abida Sharif, Jian Ping Li, Muhammad Irfan Sharif
A novel virtual force-based data aggregation mechanism with mobile sink in wireless sensor networks
Shengchao Su, Shuguang Zhao
Research on a reduced order closed-loop identification algorithms based on AIC for process with time delay
Yimin Zheng, Guoli Ji, Zhuoyun Nie, Jiangyin Huang
Gesture recognition based on binocular vision
Du Jiang, Zujia Zheng, Gongfa Li, Ying Sun, Jianyi Kong, Guozhang Jiang, Hegen Xiong, Bo Tao, Shuang Xu, Hui Yu, Honghai Liu, Zhaojie Ju
A simplified and efficient particle swarm optimization algorithm considering particle diversity
Ya Bi, Mei Xiang, Florian Schäfer, Alan Lebwohl, Cunfa Wang
Study on multiple targets tracking algorithm based on multiple sensors
Biao Wang, Kelei Feng, Wenzhong Yang, Zhiyu Zhu
RETRACTED ARTICLE: Visualization model of big data based on self-organizing feature map neural network and graphic theory for smart cities
Xiaowei Chen, Harry Haoxiang Wang, Bin Tian
Evaluation of neighbor credit value based AODV routing algorithms for selfish node behavior detection
K. Rama Abirami, M. G. Sumithra
Electromechanical dynamic analysis for the DTC induction motor driving system of the unmanned long-wall shearer drum
Yong Wang, Changzhao Liu, Yinghua Liao
Research on data mining of permissions mode for Android malware detection
Chao Wang, Qingzhen Xu, Xiuli Lin, Shouqiang Liu
Map matching algorithm: curve simplification for Frechet distance computing and precise navigation on road network using RTKLIB
Kanta Prasad Sharma, Ramesh C. Pooniaa, Surendra Sunda
Brain tumor detection and segmentation using a wrapper based genetic algorithm for optimized feature set
S. U. Aswathy, G. Glan Devadhas, S. S. Kumar
A Cognizant agent system for optimizing cloud service searching strategy
S. Dhanasekaran, V. Vasudevan
Design and development of high performance MOS current mode logic (MCML) processor for fast and power efficient computing
K. P. Sai Pradeep, S. Suresh Kumar
Low-power and high-throughput 128-point feedforward FFT processor
V. Sarada, T. Vigneswaran, J. Selvakumar
A novel medical internet of things perception system based on visual image encryption and intrusion detection
Aiying Guo, Meihua Xu, Feng Ran, Haiyong Wang
Image processing based rice plant leaves diseases in Thanjavur, Tamilnadu
T. Gayathri Devi, P. Neelamegam
A multimodal authentication for biometric recognition system using hybrid fusion techniques
S. Velmurugan, S. Selvarajan
Segmentation of chondroblastoma from medical images using modified region growing algorithm
P. Y. Muhammed Anshad, S. S. Kumar, Shajeem Shahudheen
Performance analysis of malicious node detection in MANET using ANFIS classification approach
A. Kumaravel, M. Chandrasekaran
Preventing malicious packet dropping nodes in MANET using IFHM based SAODV routing protocol
K. Vanitha, A. M. J. Zubair Rahaman
Hybrid two-dimensional dual tree—biorthogonal wavelet transform and discrete wavelet transform with fuzzy inference filter for robust remote sensing image compression
S. Sudhakar Ilango, V. Seenivasagam, R. Madhumitha
Pairwise relative ranking technique for efficient opinion mining using sentiment analysis
P. Manivannan, C. S. Kanimozhi Selvi
Discrete model based answer script evaluation using decision tree rule classifier
Madhumitha Ramamurthy, Ilango Krishnamurthi, Sudhagar Ilango, Shanthi Palaniappan
FPGA based direct torque control with speed loop Pseudo derivative controller for PMSM drive
Karthikeyan A, Prabhakaran K. K, Nagamani C
Epileptic seizures classification in EEG signal based on semantic features and variational mode decomposition
M. Ravi Kumar, Y. Srinivasa Rao
Load forecasting for smart grid using non-linear model in Hadoop distributed file system
S. Arun Jees, Venugopal Gomathi
An enhanced communication mechanism for partitioned social overlay networks using modified multi-dimensional routing
Ahsan Hussain, Bettahally N. Keshavamurthy
Secured and memory overhead controlled data authentication mechanism in cloud computing
A. Pugazhenthi, D. Chitra
Posture based health monitoring and unusual behavior recognition system for elderly using dynamic Bayesian network
G. Anitha, S. Baghavathi Priya
Investigation on human lumbar spine MRI image using finite element method and soft computing techniques
E. Punarselvam, P. Suresh
Secure location aware routing protocol with authentication for data integrity
S. Gopinath, K. Vinoth Kumar, T. Jaya Sankar
Diagnosis of thyroid dysfunction in human blood using non-invasive method: infra red light emitting diode technique
B. Suresh Chander Kapali, S. Muttan
A novel low complexity downlink linear precoding algorithm for massive MIMO systems
D. Subitha, J. M. Mathana
Multi-agent learning technique inspired from software engineering model for permutation coded GA
S. Ayshwarya Lakshmi, S. A. Sahaaya Arul Mary
Implementation of dynamic credit rating method based on clustering and classification technology
Shenghong Ding, Yuefan Ma, Hongxia Zhou
Optimization of teaching management in colleges and universities based on dynamic programming
Huping Wang, Zhichao Wang, Sanqing Ding
A novel algorithm for real time task scheduling in multiprocessor environment
Joel Josephson, R. Ramesh
Systolic array multiplier for augmenting data center networks communication link
S. Subathradevi, C. Vennila
RETRACTED ARTICLE: A wrapper based feature selection in bone marrow plasma cell gene expression data
T. Ragunthar, S. Selvakumar
Research on the evaluation index system of college students’ class teaching quality based on association algorithm
ZhiChao Wang, Qing Tian, Xinxing Duan
Manifold regularized multiple kernel learning with Hellinger distance
Tao Yang, Dongmei Fu, Xiaogang Li, Kamil Říha
Brain tumor detection using optimisation classification based on rough set theory
T. Rajesh, R. Suja Mani Malar, M. R. Geetha
AI-based software-defined virtual network function scheduling with delay optimization
Dan Liao, Yulong Wu, Ziyang Wu, Zeyuan Zhu, Wanting Zhang, Gang Sun, Victor Chang
An innovative hybrid mathematical hierarchical regression model for breast cancer diseases analysis
B. Monica Jenefer, V. Cyrilraj
A rough set calibration scheme for energy effective routing protocol in mobile ad hoc networks
S. Sathish Kumar, P. Manimegalai, S. Karthik
Feature extraction using LR-PCA hybridization on twitter data and classification accuracy using machine learning algorithms
N. Senthil Murugan, G. Usha Devi
Adaptive clustering based breast cancer detection with ANFIS classifier using mammographic images
T. V. Padmavathy, M. N. Vimalkumar, D. S. Bhargava
Design of I-shaped dual C-slotted rectangular microstrip patch antenna (I-DCSRMPA) for breast cancer tumor detection
T. V. Padmavathy, P. Venkatesh, D. Bhargava, N. Sivakumar
Logistics automation control based on machine learning algorithm
Xiaomo Yu, Xiaoping Liao, Wenjing Li, Xinquan Liu, Zhang Tao
Wind power generation fault diagnosis based on deep learning model in internet of things (IoT) with clusters
Fei Chen, Zhongguang Fu, Zhiling Yang
Honeypot TB-IDS: trace back model based intrusion detection system using knowledge based honeypot construction model
A. Umamaheswari, B. Kalaavathi
A formal framework for software faults and permissions based on unified theory of programming
Zhilin Zhu, Xiaojian Liu
RETRACTED ARTICLE: Energy efficient scheduling for cloud data centers using heuristic based migration
G. Ganesh Kumar, P. Vivekanandan
RETRACTED ARTICLE: A voxel based morphometry approach for identifying Alzheimer from MRI images
S. Saravanakumar, P. Thangaraj
Performance analysis of sub-interleaver based turbo codes
M. Rajani Devi, K. Ramanjaneyulu, B. T. Krishna
A efficient and reliable communication to reduce broadcast storms in VANET protocol
V. Velmurugan, J. Martin Leo Manickam
An adaptive fuzzy filter for image denoising
Weiping Zhang, Mohit Kumar, Jingzhi Yang, Yunfeng Zhou, Yihua Mao
Application of fuzzy predictive control technology in automatic train operation
Yuan Cao, Lianchuan Ma, Yuzhuo Zhang
Compressed sensing in wireless sensor networks under complex conditions of Internet of things
Shuo Xiao, Tianxu Li, Yan Yan, Jiayu Zhuang
RETRACTED ARTICLE: Cloud platform wireless sensor network detection system based on data sharing
Shuo Xiao, Tianxu Li, Bin Guo, Zhenzhen Huang
Exploring eye-tracking analyses of EFL learners’ cognitive processing of reduced relative clause
Xuesong Zhai, Yan Dong, Shengfen Wang, Li Wang, Jing Yuan
Automatic mutation feature identification from well logging curves based on sliding t test algorithm
Ruishan Du, Fuhua Shang, Nan Ma
Gabor wavelet multi-linear discriminant analysis for data extraction in ECG signals
S. Velmurugan, A. Mahabub Basha, M. Vijayakumar
Diligent inquiry of lower level atmospheric clouds attenuation on earth space path links for certain Indian localities
Kandala Kalyana Srinivas, Teppala Venkata Ramana
Novel algorithm for generating basis convex hexagonal polygons and polyhedrons
Mohd. Sherfuddin Khan, E. G. Rajan, Vijay H. Mankar
Defended data transmission scheme based reliable metering for smart grid applications
K. Vedavalli, N. Muruganantham
NMA: integrating big data into a novel mobile application using knowledge extraction for big data analytics
L. Maria Michael Visuwasam, D. Paul Raj
Integrated quantum flow and hidden Markov chain approach for resisting DDoS attack and C-Worm
R. Saranya, S. Senthamarai Kannan, S. Meenakshi Sundaram
A complex contract negotiation model based on hybrid intelligent algorithm
Mei Li, Jiasheng Song, Gaofei Wang, Peiyou Chen
Research on the trusted protection technology of internet of things
Zhenhu Ning, Yongli Yang, Yahao Zhang
RETRACTED ARTICLE: Application of ARIMA and SVM mixed model in agricultural management under the background of intellectual agriculture
Qing Wen, Yapeng Wang, Haodong Zhang, Zhen Li
Two hypotheses and test assumptions based on Quantum-behaved Particle Swarm Optimization (QPSO)
Ye Chen, Xiaoping Yuan, Xiaohui Cang
Smeared spectrum jamming suppression based on time unit analysis and polarization cancellation
Xin Li, Chunyang Wang, Hui Yuan, Junpeng Shi
Research on modal parameters identification of bridge structure based on adaptive signal de-noising method
Xijun Ye, Zhuo Sun, Bingcong Chen
Research on a novel variable-frequency and phase-shift control method based on a high-voltage and high-power full-bridge converter
Xuhong Wang, Yiming Zhang, Junxia Gao
Research on a new type of electromagnetic transmitter based on PWM technology
Jialin Zhang, Yiming Zhang, Xinyue Feng, Junxia Gao
Multi-criteria recommendation schemes based on factorization machines
Yonggang Ding, Shijun Li, Wei Yu
Influence mechanism of repetition frequency on pulse position modulation in deep space laser communication
Weida Zhan, Ziqiang Hao, Rui Li, Yanfeng Tang, Yijun Wang
Distributed and scalable Sybil identification based on nearest neighbour approximation using big data analysis techniques
Chinnaiah Valliyammai, Ramalingam Devakunchari
A DEA-based MOEA/D algorithm for portfolio optimization
Zhongbao Zhou, Xianghui Liu, Helu Xiao, Shijian Wu, Yueyue Liu
Consensus disturbance rejection with channel uncertainties in directed leader-following network system
Haozhe Cao, Yanxuan Wu, Zhengjie Wang
Patch based fast noise level estimation using DCT and standard deviation
S. B. Mohan, T. A. Raghavendiran, R. Rajavel
Computation of the fluid flow and the temperature field by finite element modeling
M. Dhamodaran, S. Jegadeesan, R. Praveen Kumar
Bone trabecular analysis of proximal femur radiographs for the detection of osteoporosis using anisotropic Morlet wavelet transform
N. Shankar, S. Sathish Babu, C. Viswanathan
An hybrid metaheuristic approach for efficient feature selection
B. Madhusudhanan, P. Sumathi, N. Shunmuga Karpagam, A. Mahesh, P. Anlet Pamila Suhi
Improving Adhoc wireless sensor networks security using distributed automaton
S. Venkatraman, P. Arun Raj Kumar
Cost-effective and fault-resilient reusability prediction model by using adaptive genetic algorithm based neural network for web-of-service applications
Neelamadhab Padhy, R. P. Singh, Suresh Chandra Satapathy
Error rate performance of differential multi-pulse position modulation
Tong Wang, Ziqiang Hao, Hongzuo Li, Weida Zhan, Rui Li
Identifying trusted similar users using stochastic model and next-closure based knowledge model in online social networks
A. Christiyana ArulSelvi, S. Sendhilkumar, G. S. Mahalakshmi
Scheduling and checkpointing optimization algorithm for Byzantine fault tolerance in cloud clusters
Sathya Chinnathambi, Agilan Santhanam, Jeyarani Rajarathinam, M. Senthilkumar
An energy-efficient multi-level adaptive clustering routing algorithm for underwater wireless sensor networks
Zhiping Wan, Shaojiang Liu, Weichuan Ni, Zhiming Xu
Spatial–temporal correlation dimension reduction and unsteady granger driving factor in regional varied earth surface in GIS
Jin Zhu, Jiansong Li, Zilong Jiang
Optimized virtual space vector modulation for three-phase three-level T-type converter
Yan Xia, Jianxiao Zou, Kai Li, Zesheng Min, Lang Du
Study on pricing behaviour and capacity allocation of cloud manufacturing service platform
Xin-yu Pan, Jing-zhong Ma, Dao-zhi Zhao
Predictive big data analytic on demonetization data using support vector machine
Nattar Kannan, S. Sivasubramanian, M. Kaliappan, S. Vimal, A. Suresh
Intrusion detection system using SOEKS and deep learning for in-vehicle security
Lulu Gao, Fei Li, Xiang Xu, Yong Liu
Dynamic key dependent AES S-box generation with optimized quality analysis
Pon. Partheeban, V. Kavitha
Analysis of Blockchain technology: pros, cons and SWOT
M. Niranjanamurthy, B. N. Nithya, S. Jagannatha
Security algorithm of Internet of Things based on ZigBee protocol
Yongkang Wang, Chunxia Chen, Qijie Jiang
Supply chain scheduling optimization based on genetic particle swarm optimization algorithm
Feng Xiong, Peisong Gong, P. Jin, J. F. Fan
An optimized feature selection based on genetic approach and support vector machine for heart disease
Chandra Babu Gokulnath, S. P. Shantharajah
Study on VSC-HVDC grid topology of offshore wind farms
Nguyen Thi Hong Yen, Chen Hongkun, Le Ngoc Giang
Multimodal computer image recognition based on depth neural network
Shan Wang, YueXing Wang, HuiLing Shan, ChunXiang Shi
RETRACTED ARTICLE: The application researches of visualized data mining technique in urban underground space based on GIS
Fayong Zhang, Caixian Li, Yunling Yang
An improved preference method for the FAST TCP protocol parameter
Weibin Wang, Xiaolong Chen, Chengfu Wang, Henry Ren He
On-line modeling and monitoring for multi-operation batch processes with infinite data types
Yajun Wang, Fuming Sun, Dongjuan Li
Hash based manifold learning technique to generating random fields for image segmentation
Rambabu Pemula, C. Naga Raju
Application of industry linkage path algorithm in western energy development
Fanyong Zhang, Qiansheng Gong
RETRACTED ARTICLE: Application effect analysis of the test system of track and field web course based on software programming method
Weiliang Lin, Dongyang Wang, Haiyan Cui, Nian Li
Modeling and analysis of a bus fire accident for evaluation of fire safety door using the fire dynamics simulator
Cherng-Shing Lin, Jui-Pei Hsu
Mobility prediction in mobile ad hoc networks using eye of coverage approach
U. Palani, K. C. Suresh, Alamelu Nachiappan
Efficient data integrity and data replication in cloud using stochastic diffusion method
M. Ramanan, P. Vivekanandan
High performance decoding aware FPGA bit-stream compression using RG codes
J. Satheesh Kumar, G. Saravana Kumar, A. Ahilan
Support vector machine algorithm for artificial intelligence optimization
Xian Tan, Fasheng Yu, Xifeng Zhao
Improved pharma education system in the field of medical images using compression techniques
M. Rajasekhar Reddy, K. S. Ravichandran, B. Venkatraman, K. R. Sekar, R. Manikandan
Multi level incremental influence measure based classification of medical data for improved classification
K. Ananthajothi, M. Subramaniam
The study on limited asynchronous breaking based on the adjustment of breaking time
Xianghao Zeng, Haichuan Zhang, Jiyan Zou, Zhihui Huang
How does local government’s information affect farmers’ agricultural investment: based on theoretical and empirical analysis
Bao Zhu, Jing He, Shiting Zhai
Numerical simulation of the Sandia Flame D using the ESF method coupled with FGM model
Yifan Duan, Zhixun Xia, Likun Ma, Zhenbing Luo
Morphometric analysis of X-ray and CT images for evaluating osteoporosis
N. Shankar, S. Sathish Babu, C. Viswanathan
A novel flip-flop based error free, area efficient and low power pipeline architecture for finite impulse recursive system
Raja Krishnamoorthy, S. Saravanan
Simulation research on shielding effect of computerized boxes with electromagnetic pulse hole based on finite element analysis
Bing Cao, Xuchao Pan, Chenglong Liu, Maolei Zhang, Wencan Jiang
Approach to generation of random aggregate model and gradient optimization of background grid based on SolidWorks platform
Xun He, Yong He, Xuchao Pan, Lei Guo
An algebraic complex event processing method for cyber-physical system
Cheng Zhou, Youqian Feng, Zhonghai Yin
Criterion for realizing state-delayed digital filters subjected to external interference employing saturation arithmetic
Priyanka Kokil, C. G. Parthipan, Srinivasulu Jogi, Haranath Kar
Fast implementation of area integral model SART algorithm based on look-up table
Shunli Zhang, Guohua Geng, Zhan Li, Yuhe Zhang
An enhanced intrusion detection system for mobile ad-hoc network based on traffic analysis
K. Bala, S. Jothi, A. Chandrasekar
Tsallis entropy: as a new single feature with the least computation time for classification of epileptic seizures
M. Thilagaraj, M. Pallikonda Rajasekaran, N. Arun Kumar
Defect detection in pattern texture analysis using improved support vector machine
I. Manimozhi, S. Janakiraman
Design of test pattern generator (TPG) by an optimized low power design for testability (DFT) for scan BIST circuits using transmission gates
G. Naveen Balaji, S. Chenthur Pandian
RETRACTED ARTICLE: Research on process customization technology for intelligent transportation cloud service platform
Hua Pan, Zhongxiang Huang, Zengzhen He
Knowledge diffusion simulation of knowledge networks: based on complex network evolutionary algorithms
Li Zhang, Qifeng Wei, Yuan Yuan, Yuxue Li
Analysis and design of an attitude calculation algorithm based on elman neural network for SINS
Chengjun Guo, Jiahan Yan, Zhong Tian
Zone-based dual sub sink for network lifetime maximization in wireless sensor network
K. Arthi, A. Singara Rajiva Lochana
Online customer service quality of online shopping: evidence from Dangdang.com
Zhengwei Huang, Yin Luo, Dong Wang
Non-rigid registration of multi-phase liver CT data using fully automated landmark detection and TPS deformation
Xuejun Zhang, Xiaomin Tan, Xin Gao, Dongbo Wu, Xiangrong Zhou, Hiroshi Fujita
A method of evaluating the three-dimensional damage effect of strong electromagnetic pulse on the box based on the triangular-element FDTD method
Bing Cao, Xuchao Pan, Maolei Zhang, Chenglong Liu, Wencan Jiang
Research on image segmentation method using a structure-preserving region model-based MRF
Chenghua Fan, Qunjing Wang
Study on learning effect prediction models based on principal component analysis in MOOCs
Wei Zhang, Shiming Qin, Baolin Yi, Peng Tian
Construction and application of barrel finishing underlying database platform
Wei Gao, Shengqiang Yang, Jianyan Tian, Amit Banerjee, Fei Yan
Product pricing considering the consumer preference based on Internet of Things
Xin-yu Pan, Jing-zhong Ma, Cheng-xia Wu
Experience data excavating based distributed occasional communication establishing for swarm in remote region
Changhua Yao, Lei Wang, Xiaohan Yu
Remotely assessing above-ground fresh biomass weight of wheat based on the combinations of pair vegetation indexes from HJ-CCD images
Changwei Tan, Qing Zhang, Jian Zhou, Ying Du, Dunliang Wang, Ming Luo, Haidong Zhang, Wenshan Guo
Multi-objective optimization of high altitude sector operation based on environmental protection
Yong Tian, Lili Wan, Bojia Ye
RETRACTED ARTICLE: Application of optimized genetic algorithm based on big data in bus dynamic scheduling
Xiaoqiang Wang, Ren Qing-dao-er-ji
Solving the time-dependent multi-trip vehicle routing problem with time windows and an improved travel speed model by a hybrid solution algorithm
Yan Sun, Danzhu Wang, Maoxiang Lang, Xuesong Zhou
Masked 3D conditional generative adversarial network for rock mesh generation
Ping Kuang, Dingli Luo, Haoshuang Wang
A new concept of Cosine similarity measures based on dual hesitant fuzzy sets and its possible applications
Yutao Zhang, Lei Wang, Xiaohan Yu, Changhua Yao
Study on the transform method of estimating discrete frequency from continuous variable: ratemaking for car repair insurance based on SAS system coding
Yuantao Xie, Huijuan Lv, Xiaoke Sun, Yu Mao, Juan Yang
An improved calculation system for phase-functioned neural network and implementation in unreal engine
Ping Kuang, Dingli Luo, Haoshuang Wang, Lixue Zhang
Bilevel mixed-integer nonlinear programming for integrated scheduling in a supply chain network
Jianchao Yang, Feng Guo, Li Luo, Xiaoming Ye
Construction of a knee osteoarthritis diagnostic system based on X-ray image processing
Yongping Li, Ning Xu, Qiang Lyu
Semi-Markov chain-based grey prediction-based mitigation scheme for vampire attacks in MANETs
P. Balaji Srikaanth, V. Nagarajan