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On the Analysis Method of the Triple Test Cross Design
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作者 Jin Yi(Northeast Agricultural University, Harbin 1 50030, P R C) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1995年第1期66-74,共9页
The analysis method of the triple test cross design has been discussed carefully from the two factor experiment design and the genetic models of additive dominant effect and of epistasis effect.Two points different f... The analysis method of the triple test cross design has been discussed carefully from the two factor experiment design and the genetic models of additive dominant effect and of epistasis effect.Two points different from the previous reports have been concluded: (1)both the degrees of freedom of the orthogonal terms C2 and C3 are m, (2)the denominator in the F test to C2 and C3 is the error mean of square between plots. 展开更多
关键词 Triple test cross design Additive-dominant model Epistasis model Genetic parameter estimate.
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Novel Optimized Cross-Layer Design with Maximum Weighted Capacity Based Resource Allocation for AMC/HARQ Wireless Networks 被引量:1
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作者 Reham A. El-Mayet Hesham M. El-Badawy Salwa H. Elramly 《Wireless Engineering and Technology》 2013年第2期77-86,共10页
To provide quality-of service (QoS) guarantees for heterogeneous applications, most recent wireless communications technologies and standards combine the error-correcting capability of hybrid automatic repeat request ... To provide quality-of service (QoS) guarantees for heterogeneous applications, most recent wireless communications technologies and standards combine the error-correcting capability of hybrid automatic repeat request (HARQ) schemes at the data link layer (DLL) with the adaptation ability of the adaptive modulation and coding (AMC) modes at the physical layer (PHY) layer. This paper aims to investigate the aggregated system capacity as well as the breakdown of this capacity for different ACM modes in each HARQ scheme. This investigation was done by using maximum weighted capacity (MWC) resource allocation at the PHY layer in conjunction with a novel packet error rate (PER)-based scheduling at the medium access control (MAC) layer. As a result, the dominant AMC mode corresponding to channel SNR was available. 展开更多
关键词 AMC cross-LAYER design HARQ Nakagami-m FADING Channel QoS
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Cross-Layer Design Based Optimized Link State Routing Protocol for Wireless Mesh Networks
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作者 Huai-Yu Wen Guang-Chun Luo 《Journal of Electronic Science and Technology》 CAS 2011年第4期368-372,共5页
A proactive routing protocol CL-OLSR (cross-layer based optimized link state routing) by using a brand-new routing metric CLM (cross-layer metric) is proposed. CL-OLSR takes into account four link quality impact f... A proactive routing protocol CL-OLSR (cross-layer based optimized link state routing) by using a brand-new routing metric CLM (cross-layer metric) is proposed. CL-OLSR takes into account four link quality impact factors in route calculation through the cross-layer operation mechanism: the node available bandwidth, the node load, the link delivery rate, and the link interference, and thus the effect of route selection is optimized greatly. The simulation results show that the proposed CL-OLSR protocol can not only improve the network throughput to a large extent, but also reduce the end-to-end delay, while achieving load balance route results. 展开更多
关键词 cross-layer design proactive routing routing protocol wireless mesh network.
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Cross Layered MAC Design for RF Energy Harvesting Sensor Network
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作者 Thangavelu Sasikala Veerasamy Jawahar Senthil Kumar 《Circuits and Systems》 2016年第9期2676-2688,共13页
The main research objective in wireless sensor networks (WSN) domain is to develop algorithms and protocols to ensure minimal energy consumption with maximum network lifetime. In this paper, we propose a novel design ... The main research objective in wireless sensor networks (WSN) domain is to develop algorithms and protocols to ensure minimal energy consumption with maximum network lifetime. In this paper, we propose a novel design for energy harvesting sensor node and cross-layered MAC protocol using three adjacent layers (Physical, MAC and Network) to economize energy for WSN. The basic idea behind our protocol is to re-energize the neighboring nodes using the radio frequency (RF) energy transmitted by the active nodes. This can be achieved by designing new energy harvesting sensor node and redesigning the MAC protocol. The results show that the proposed cross layer CL_EHSN improves the life time of the WSN by 40%. 展开更多
关键词 Wireless Sensor Network cross Layer design RF Energy Harvesting Lifetime Enhancement
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Performance of Cross-Layer Design with Power Allocation in Space-Time Coded MIMO Systems
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作者 杨定礼 刘岩 虞湘宾 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2014年第4期431-439,共9页
A cross-layer design(CLD)scheme with combination of power allocation,adaptive modulation(AM)and automatic repeat request(ARQ)is presented for space-time coded MIMO system under imperfect feedback,and the corresponding... A cross-layer design(CLD)scheme with combination of power allocation,adaptive modulation(AM)and automatic repeat request(ARQ)is presented for space-time coded MIMO system under imperfect feedback,and the corresponding system performance is investigated in a Rayleigh fading channel.Based on imperfect feedback information,a suboptimal power allocation(PA)scheme is derived to maximize the average spectral efficiency(SE)of the system.The scheme is based on a so-called compressed SNR criterion,and has a closed-form expression for positive power allocation,thus being computationally efficient.Moreover,it can improve SE of the presented CLD.Besides,due to better approximation,it obtains the performance close to the existing optimal approach which requires numerical search.Simulation results show that the proposed CLD with PA can achieve higher SE than the conventional CLD with equal power allocation scheme,and has almost the same performance as CLD with optimal PA.However,it has lower calculation complexity. 展开更多
关键词 cross-layer design(CLD) power allocation(PA) space-time coding spectral efficiency(SE) packet error rate(PER)
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On Cross-Layer Design of AMC Based on Rate Compatible Punctured Turbo Codes
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作者 Fotis Foukalas Evangelos Zervas 《International Journal of Communications, Network and System Sciences》 2010年第3期256-265,共10页
This paper extends the work on cross-layer design which combines adaptive modulation and coding at the physical layer and hybrid automatic repeat request protocol at the data link layer. By contrast with previous work... This paper extends the work on cross-layer design which combines adaptive modulation and coding at the physical layer and hybrid automatic repeat request protocol at the data link layer. By contrast with previous works on this topic, the present development and the performance analysis as well, is based on rate compatible punctured turbo codes. Rate compatibility provides incremental redundancy in transmission of parity bits for error correction at the data link layer. Turbo coding and iterative decoding gives lower packet error rate values in low signal-to-noise ratio regions of the adaptive modulation and coding (AMC) schemes. Thus, the applied cross-layer design results in AMC schemes can achieve better spectral efficiency than convolutional one while it retains the QoS requirements at the application layer. Numerical results in terms of spectral efficiency for both turbo and convolutional rate compatible punctured codes are presented. For a more comprehensive presentation, the performance of rate compatible LDPC is contrasted with turbo case as well as the performance complexity is discussed for each of the above codes. 展开更多
关键词 cross-LAYER design Adaptive Modulation and Coding RATE-COMPATIBLE Punctured Turbo CODES Hybrid ARQ CODES Complexity
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Cross Layer Design for Cooperative Transmission in Wireless Sensor Networks
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作者 Kanojia Sindhuben Babulal Rajiv Ranjan Tewari 《Wireless Sensor Network》 2011年第6期209-214,共6页
Several protocols and schemes have been proposed to reduce energy consumption in Wireless Sensor Net-works (WSNs). In this paper we employ farcoopt, a cross layer design approach with the concept of coop-eration among... Several protocols and schemes have been proposed to reduce energy consumption in Wireless Sensor Net-works (WSNs). In this paper we employ farcoopt, a cross layer design approach with the concept of coop-eration among the nodes with best farthest neighbor scheme to increase the Quality of Service (QoS), reduce energy consumption, increases performance and end-to-end throughput. We present cooperative transmission to connect previously disconnect parts of a network thus overcoming the separation problem of multi-hop network. We show that this approach improves connectivity over 50% compared to multi-hop approaches and reduces the number of nodes necessary to provide full coverage of an area up to 35%. Simulation results show that on increase of data rates i.e. packet the network life time increases in farcoopt as compared to tra-ditional multi hop approach. The result of this analysis is presented in this work. 展开更多
关键词 COOPERATIVE Network cross Layer design WIRELESS Sensor Networks Energy SAVING Communication PROTOCOL ROUTING
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Cross-layer design of combining AMC with HARQ in cooperative relay system with perfect and imperfect CSI
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作者 唐伦 张荣荣 陈前斌 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第4期118-128,共11页
A cross-layer design which combines adaptive modulation and coding (AMC) at the physical layer with a hybrid automatic repeat request (HARQ) protocol at the data link layer (LL) is presented, in cooperative relay syst... A cross-layer design which combines adaptive modulation and coding (AMC) at the physical layer with a hybrid automatic repeat request (HARQ) protocol at the data link layer (LL) is presented, in cooperative relay system over Nakagami-m fading channels with perfect and imperfect channel state information (CSI). In order to maximize spectral efficiency (SE) under delay and packet error rate (PER) performance constraints, a state transition model and an optimization framework with perfect CSI are presented. Then the framework is extended to cooperative relay system with imperfect CSI. The numerical results show that the scheme can achieve maximum SE while satisfying transmitting delay requirements. Compared with the imperfect CSI, the average PER with perfect CSI is much lower and the spectral efficiency is much higher. 展开更多
关键词 COOPERATIVE relay system cross-layer design and optimization adaptive modulation and coding (AMC) hybrid automatic REPEAT request (HARQ) PERFECT channel state information(CSI) imperfect CSI
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DESIGN OF LIGHTWEIGHT PUF CIRCUIT BASED ON SELECTABLE CROSS-COUPLED INVERTERS
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作者 Zhang Xuelong Li Jianrui +1 位作者 Wang Pengjun Zhang Yuejun 《Journal of Electronics(China)》 2014年第6期513-518,共6页
By analyzing the principle of process variations, a lightweight Physical Unclonable Function (PUF) circuit based on selectable cross-coupled inverters is proposed in this paper. Firstly, selectable cross-coupled inv... By analyzing the principle of process variations, a lightweight Physical Unclonable Function (PUF) circuit based on selectable cross-coupled inverters is proposed in this paper. Firstly, selectable cross-coupled inverters are chosen for two delay paths. Simultaneously, the circuit takes challenge signal to control each delay path. The PUF cell circuit is implemented in Semiconductor Manufacturing International Corporation (SMIC) 65 nm CMOS technology and the layout area is 2.94μm × 1.68μm. Then the 64-bit PUF circuit is achieved with the cascade connection of cell circuits. The simulation results show that the randomness is 49.4% and the reliability is 96.5%. Compared to the other works, this PUF circuit improves the encrypt performance and greatly reduces the area. 展开更多
关键词 LIGHTWEIGHT Physical Unclonable Punction (PUF) cross-coupled inverter Circuit design
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Overall Selection Design Based on the Mega Highway Bridge Project
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作者 Rongpeng Xu 《Journal of World Architecture》 2024年第4期27-32,共6页
In the continuous development of the modern highway and bridge engineering industry,the reasonable selection of mega highway bridges and their design is crucial.Based on this,this paper takes the actual bridge project... In the continuous development of the modern highway and bridge engineering industry,the reasonable selection of mega highway bridges and their design is crucial.Based on this,this paper takes the actual bridge project as an example,and analyses the overall selection design of such highway bridges,including the basic overview of the project,the basic selection principle of mega highway bridge project structure and its design strategy,etc.,to provide scientific reference for its selection design. 展开更多
关键词 Mega highway bridge Selection principle Selection design for railway crossing Selection design for road crossing
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CONTOUR DESIGN AND PRACTICE FOR A LOW RADAR CROSS SECTION VEHICLE
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作者 Zhang Zhongan Wang Lue(Research Institute of Pilotless Aircraft, Nanjing University of Aeronautics and Astronautics, Nanjing, China, 210016) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1996年第1期43-47,共5页
On the basis of the canard configuration a contour stealth design including chiefly the wing, the fuselage and their connection type is projected. The prime project of a blended wing body vehicle with canard is provid... On the basis of the canard configuration a contour stealth design including chiefly the wing, the fuselage and their connection type is projected. The prime project of a blended wing body vehicle with canard is provided and through the change of the fuselage head form and the different fin disposals, the radar cross section (RCS) is optimized. The average value of RCS and the value of RCS in the ± 45 ° front sector for different designs are illustrated. The model measurement proves that the project having a sharp head fuselage and 30 ° angle double fin has the minimum value of RCS. The wind tunnel test to the model with RCS optimized proved that the vehicle project has excellent aerodynamic characteristics such as high lift curve slope, up to 26° stalling angle, high lift / drag ratio equal to 8, and also has low RCS value in the front sector and in the lateral sector. 展开更多
关键词 aircraft design electromagnetic scattering wind tunnel tests radar cross section
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从物象到拟像:花瑶挑花蛇纹的叙事结构研究
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作者 张德胜 《丝绸》 北大核心 2025年第2期21-28,共8页
纹样的设计过程是意义的编织和生成过程,意味着纹样设计行为存在于物象到纹样之间的转化过程之中。为系统了解花瑶挑花蛇纹的叙事结构,文章尝试将设计视为“物象—拟像”转化的中介角色对蛇纹的造型特征和装饰方法进行探索,并逐次归类,... 纹样的设计过程是意义的编织和生成过程,意味着纹样设计行为存在于物象到纹样之间的转化过程之中。为系统了解花瑶挑花蛇纹的叙事结构,文章尝试将设计视为“物象—拟像”转化的中介角色对蛇纹的造型特征和装饰方法进行探索,并逐次归类,总结出设计者对物象的阅读及表现方式,同时形成花瑶挑花蛇纹设计的结构方程及在以蛇纹为母题的组合纹样中的叙事文本。面对文化融合背景下的花瑶挑花纹样的转型现象,对传统设计文法的析解有助于传统花瑶文化的创新传承与发展。 展开更多
关键词 拟像 花瑶挑花 蛇纹 设计中介 结构 叙事
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挠性陀螺交叉耦合影响因素分析及控制
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作者 蔡曜 司玉辉 +2 位作者 王玉琢 杜鑫 尹路 《北京航空航天大学学报》 北大核心 2025年第1期141-151,共11页
由于机械结构误差和电气干扰,实际生产的挠性陀螺存在交叉耦合。分析交叉耦合影响因素,确定其为差动式电感传感器铁芯柱垂直度和力矩器线圈周向偏移角度,由此建立传感器、力矩器的误差模型,定量分析了各影响因素对交叉耦合的影响程度。... 由于机械结构误差和电气干扰,实际生产的挠性陀螺存在交叉耦合。分析交叉耦合影响因素,确定其为差动式电感传感器铁芯柱垂直度和力矩器线圈周向偏移角度,由此建立传感器、力矩器的误差模型,定量分析了各影响因素对交叉耦合的影响程度。设计铁芯柱精密装配工装、线圈精密装配工装,并对力矩器进行可调设计,控制挠性陀螺交叉耦合。工程实践表明:各项控制方法均取得较好效果,交叉耦合稳定控制为不大于1%;各项控制方法提高了挠性陀螺对角速度的测量精度,进而提高了惯导系统的导航精度。 展开更多
关键词 挠性陀螺 交叉耦合 影响因素 差动式电感传感器 力矩器 可调设计
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A CROSS-LAYER STRATEGY FOR COOPERATIVE DIVERSITY IN WIRELESS SENSOR NETWORKS 被引量:1
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作者 ChenYongrui YangYang YiWeidong 《Journal of Electronics(China)》 2012年第1期33-38,共6页
We investigate the problem of how to minimize the energy consumption in multi-hop Wireless Sensor Network (WSN),under the constraint of end-to-end reliability Quality of Seervice (QoS) requirement.Based on the investi... We investigate the problem of how to minimize the energy consumption in multi-hop Wireless Sensor Network (WSN),under the constraint of end-to-end reliability Quality of Seervice (QoS) requirement.Based on the investigation,we jointly consider the routing,relay selection and power allocation algorithm,and present a novel distributed cross-layer strategy using opportunistic relaying scheme for cooperative communication.The results show that under the same QoS requirement,the proposed cross-layer strategy performs better than other cross-layer cooperative communication algorithms in energy efficiency.We also investigated the impact of several parameters on the energy efficiency of the cooperative communication in WSNs,thus can be used to provide guidelines to decide when and how to apply cooperation for a given setup. 展开更多
关键词 Wireless Sensor Network (WSN) cross-layer design Cooperative diversity Opportun-istic relaying
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Proposal for a cross layer scheme for real-time wireless video
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作者 JEYARAJ Arulsaravana CHENG Liang EL ZARKI Magda 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第10期1690-1694,共5页
This paper focuses on the design of the cross layer between the video application layer and the MIMO physical layer. MIMO physical layer research has promised an enormous increase in the capacity of wireless communica... This paper focuses on the design of the cross layer between the video application layer and the MIMO physical layer. MIMO physical layer research has promised an enormous increase in the capacity of wireless communication systems. Also MIMO wireless systems operate under fading conditions where the channel faces arbitrary fluctuations. Since the wireless channel changes over each coherence period, the capacity of the wireless channel, given the power constraints, changes. Hence to make efficient use of the available capacity one needs to adapt the video bit rate. However it is impossible to adapt at the application layer as changing the parameters of the video takes more time than the coherence period of the channel. In this paper we address this problem through a novel solution and also investigate its performance through a simulation study. 展开更多
关键词 MIMO V-BLAST Adaptive modulation Diversity Constant bit rate (CBR) cross layer design Power control Fine granular scalability (FGS)
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An Energy-Efficient Access Control Algorithm with Cross-Layer Optimization in Wireless Sensor Networks 被引量:1
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作者 Zhi Chen Shaoqian Li 《Wireless Sensor Network》 2010年第2期168-172,共5页
This paper presents a wireless sensor network (WSN) access control algorithm designed to minimize WSN node energy consumption. Based on slotted ALOHA protocol, this algorithm incorporates the power control of physical... This paper presents a wireless sensor network (WSN) access control algorithm designed to minimize WSN node energy consumption. Based on slotted ALOHA protocol, this algorithm incorporates the power control of physical layer, the transmitting probability of medium access control (MAC) layer, and the automatic repeat request (ARQ) of link layer. In this algorithm, a cross-layer optimization is preformed to minimizing the energy consuming per bit. Through theory deducing, the transmitting probability and transmitting power level is determined, and the relationship between energy consuming per bit and throughput per node is provided. Analytical results show that the cross-layer algorithm results in a significant energy savings relative to layered design subject to the same throughput per node, and the energy saving is extraordinary in the low throughput region. 展开更多
关键词 Wireless Sensor Network (WSN) cross-LAYER design ENERGY Efficient ENERGY CONSUMPTION per Bit THROUGHPUT
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Cross-layer Enhancement to Multi-hop Routing in Sensor Networks: an Empirical Study
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作者 SHANG Zhi-Jun WANG Jun YU Hai-Bin 《自动化学报》 EI CSCD 北大核心 2006年第6期875-880,共6页
Lossy link is one of the unique characteristics in random-deployed sensor networks. We envision that robustness and reliability of routing cannot be ensured purely in network layer. Our idea is to enhance the performa... Lossy link is one of the unique characteristics in random-deployed sensor networks. We envision that robustness and reliability of routing cannot be ensured purely in network layer. Our idea is to enhance the performance of routing protocol by cross-layer interaction. We modified mint protocol, a routing protocol in TinyOS and proposed an enhanced version of mint called PA-mint. A transmission power control interface is added to network layer in PA-mint. When routing performance of the current network is not satisfied, PA-mint monotonically increases the transmission power via the interface we added. PA-mint is able to connect orphan nodes and robust to node mobility or key nodes failure. In the case that automatic request retransmission is employed, the number of retransmissions can be reduced by PA-mint. Results from experiments show that PA-mint increases the reliability and robustness of routing protocol by cross-layer interaction. 展开更多
关键词 Sensor networks ROUTING cross-layer design
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LOW RCS MODIFIED DESIGN OF EXTERNAL CARRIAGE AND ANALYSIS OF ITS SCATTERING CHARACTERISTIC
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作者 马东立 黄沛霖 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2000年第3期152-156,共5页
An external carriage and a wing have a high radar cross section (RCS) level in a wide range of angles of pitch because they form an efficient corner reflector. Coupling scattering between the external carriage and the... An external carriage and a wing have a high radar cross section (RCS) level in a wide range of angles of pitch because they form an efficient corner reflector. Coupling scattering between the external carriage and the wing is controlled by designing a saw tooth structure of the external carriage on condition that the wing structure is not changed. A low RCS saw tooth scheme of the external carriage is given in the paper. The ray tracing method and the physical theory of diffraction are used to calculate the radar scattering characteristics of low RCS structures of the external carriage and wing. The results show that the saw tooth scheme of the external carriage is feasible and effective for low RCS design. 展开更多
关键词 external carriage radar cross section design scattering characteristics
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花瑶挑花纹样在女士皮包中的创新设计与应用
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作者 刘辉超 张毅 《皮革科学与工程》 CAS 北大核心 2025年第1期89-97,共9页
花瑶挑花纹样造型多样、设计精巧,具有较高的美学价值与应用价值,但将其创新应用至箱包设计领域的相关研究却相对较少。从设计学角度出发,分析花瑶挑花的典型图案和文化内涵,归纳其核心元素特征;调查研析消费人群及其风格偏好,确立产品... 花瑶挑花纹样造型多样、设计精巧,具有较高的美学价值与应用价值,但将其创新应用至箱包设计领域的相关研究却相对较少。从设计学角度出发,分析花瑶挑花的典型图案和文化内涵,归纳其核心元素特征;调查研析消费人群及其风格偏好,确立产品的设计定位;选取典型挑花纹样,运用形状文法和风格迁移算法分别进行创新再造设计,并结合3D数字化软件将创新方案应用于时尚女包设计中,开发出兼具民族特色和现代形式美感的革制品。通过将数字化技术手段与花瑶挑花纹样皮具的有机结合,既保证了挑花纹样的迭代与创新,又提高了革制品图案设计的创作效率。 展开更多
关键词 挑花 纹样 女包 形状文法 风格迁移算法 创新 设计 花瑶
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Role of Cross Layer Based Intrusion Detection System for Wireless Domain
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作者 Ravneet Kaur 《International Journal of Communications, Network and System Sciences》 2012年第2期81-85,共5页
Wireless mesh networks are very common both for organizations and individuals. Many laptops, computers have wireless cards pre-installed for buyer. However a wireless networking has many security issues. An intrusions... Wireless mesh networks are very common both for organizations and individuals. Many laptops, computers have wireless cards pre-installed for buyer. However a wireless networking has many security issues. An intrusions detection system aim to detect the different attacks against network and system. An intrusion detection system should be capable for detecting the misuse of the network whether it will be by the authenticated user or by an attacker. They detect attempts and active misuse either by legitimate users of the information systems or by external. The present paper deals with cross layer based intrusion detection system for wireless domain—a critical anlaysis. The present paper deals with role of cross layer based intrusion detection system for wireless domain. 展开更多
关键词 cross Layer design INTRUSION Detection RADIO Frequency (RF)
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