• Title/Summary/Keyword: Diff

Search Result 327, Processing Time 0.027 seconds

Performance analysis of Frequent Itemset Mining Technique based on Transaction Weight Constraints (트랜잭션 가중치 기반의 빈발 아이템셋 마이닝 기법의 성능분석)

  • Yun, Unil;Pyun, Gwangbum
    • Journal of Internet Computing and Services
    • /
    • v.16 no.1
    • /
    • pp.67-74
    • /
    • 2015
  • In recent years, frequent itemset mining for considering the importance of each item has been intensively studied as one of important issues in the data mining field. According to strategies utilizing the item importance, itemset mining approaches for discovering itemsets based on the item importance are classified as follows: weighted frequent itemset mining, frequent itemset mining using transactional weights, and utility itemset mining. In this paper, we perform empirical analysis with respect to frequent itemset mining algorithms based on transactional weights. The mining algorithms compute transactional weights by utilizing the weight for each item in large databases. In addition, these algorithms discover weighted frequent itemsets on the basis of the item frequency and weight of each transaction. Consequently, we can see the importance of a certain transaction through the database analysis because the weight for the transaction has higher value if it contains many items with high values. We not only analyze the advantages and disadvantages but also compare the performance of the most famous algorithms in the frequent itemset mining field based on the transactional weights. As a representative of the frequent itemset mining using transactional weights, WIS introduces the concept and strategies of transactional weights. In addition, there are various other state-of-the-art algorithms, WIT-FWIs, WIT-FWIs-MODIFY, and WIT-FWIs-DIFF, for extracting itemsets with the weight information. To efficiently conduct processes for mining weighted frequent itemsets, three algorithms use the special Lattice-like data structure, called WIT-tree. The algorithms do not need to an additional database scanning operation after the construction of WIT-tree is finished since each node of WIT-tree has item information such as item and transaction IDs. In particular, the traditional algorithms conduct a number of database scanning operations to mine weighted itemsets, whereas the algorithms based on WIT-tree solve the overhead problem that can occur in the mining processes by reading databases only one time. Additionally, the algorithms use the technique for generating each new itemset of length N+1 on the basis of two different itemsets of length N. To discover new weighted itemsets, WIT-FWIs performs the itemset combination processes by using the information of transactions that contain all the itemsets. WIT-FWIs-MODIFY has a unique feature decreasing operations for calculating the frequency of the new itemset. WIT-FWIs-DIFF utilizes a technique using the difference of two itemsets. To compare and analyze the performance of the algorithms in various environments, we use real datasets of two types (i.e., dense and sparse) in terms of the runtime and maximum memory usage. Moreover, a scalability test is conducted to evaluate the stability for each algorithm when the size of a database is changed. As a result, WIT-FWIs and WIT-FWIs-MODIFY show the best performance in the dense dataset, and in sparse dataset, WIT-FWI-DIFF has mining efficiency better than the other algorithms. Compared to the algorithms using WIT-tree, WIS based on the Apriori technique has the worst efficiency because it requires a large number of computations more than the others on average.

Performance Analysis of QoS Mechanism Using DiffServ in IPOA Networks (IPOA 망에서 DiffServ를 이용한 QoS 메커니즘의 성능분석)

  • 문규춘;최현호;박광채
    • Proceedings of the IEEK Conference
    • /
    • 2000.11a
    • /
    • pp.307-310
    • /
    • 2000
  • ATM is the switching and multiplexing technology chosen by the ITU-T for the operation of B-lSDN. Basically, ATM technology is designed to combine the reliability of circuit switching with the efficiency and flexibility of packet switching technology. For servicing QoS in IPOA(IP over ATM) when the larger effort is given, it will be the good method that the original QoS benefits having ATM switching have in ATM layer underlying layer. The IETF has recently proposed Differentiated Services framework for provision of QoS. In this paper we analyse performance of two Diffserv mechanism. Threshold Dropping and Priority Scheduling. Threshold Dropping and Priority Scheduling can be regarded as basic mechanisms from which the other mechanisms have been derived. Hence comparative performance of these two mechanisms in providing required QoS is an important issue. In this Paper we carry out a performance comparison of the TD and PS mechanisms with the aim of providing the same level of packet loss to the preferred flow. Our comparison of the TD and PS allows us to determine resultant packet loss for the non-preferred flows as a function of various parameters of the two mechanisms.

  • PDF

A Study on a Traffic Conditioning Scheme for Alleviating a bias against Reserved Bandwidth Size in Differentiated Services Network (차별 서비스 네트워크에서 예약 대역폭의 편향성을 완화하는 트래픽 조절 기법 연구)

  • 이성근
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.6 no.2
    • /
    • pp.228-235
    • /
    • 2002
  • Differentiated services network (DiffServ) aims to provide the same service to a group of connections that have similar Quality of Service requirements. One of the essential function to realize DiffServ is the traffic conditioning mechanisms to support the required services. The paper proposes the enhanced traffic conditioning mechanism which alleviates a bias against reserved bandwidth size. The simulation results show that the new mechanism is rather insensitive of size of reserved bandwidth, and performs better both in terms of throughput assurance and fair distribution of excess bandwidth in case of well-provisioned and over-provisioned network environment.

A Traffic Conditioning Mechanism for Enhancing the Fairness of TCP and UDP Flows (TCP 와 UDP 흐름의 공평성 향상을 위한 트래픽 조절 메커니즘)

  • Lee, Sung-Keun
    • The Journal of Korean Association of Computer Education
    • /
    • v.7 no.1
    • /
    • pp.37-44
    • /
    • 2004
  • Differentiated services network (DiffServ) aims to provide the same service to a group of connections that have similar Quality of Service requirements. One of the essential function to realize DiffServ is the traffic conditioning mechanism. The paper proposes the enhanced traffic conditioning mechanism which can assure the reserved rates of TCP and UDP flows and support fair distribution of excess bandwidth. The simulation results show that the new mechanism is rather insensitive of the effect of UDP against TCP throughput, and performs better both in terms of throughput assurance and fair distribution of excess bandwidth in case of well-provisioned and over-provisioned network environment.

  • PDF

An Experimental Evaluation of Active Bandwidth Allocation Model for DiffServ Support in MPLS Networks (MPLS망에서 차등화 서비스 지원을 위한 동적 대역폭 할당 모델의 실험적 평가)

  • Kim Sung-Chan;Chang Kun-Won;Oh Hae-Seok
    • The KIPS Transactions:PartC
    • /
    • v.11C no.6 s.95
    • /
    • pp.807-814
    • /
    • 2004
  • This paper researches and evaluates a bandwidth reallocation mechanism for efficient DiffServ QoS support in MPLS networks by monitoring the network traffic status and reallocating unused bandwidth. While the Differentiated Services in MPLS Networks architecture provides QoS management through the RSVP resource reservation, this mechanism is based on a static provisioning of resource. But this approach can lead to waste bandwidth in some service classes or, leave some service classes' resource starved. This paper presents the bandwidth reallocation dynamically based on network traffic status for bandwidth usage maximization.

Characteristics of deconstruction expressed in the contemporary knit fashion (현대 니트패션에 나타난 해체주의 특성)

  • Lee, Yoon Mee
    • The Research Journal of the Costume Culture
    • /
    • v.26 no.4
    • /
    • pp.583-597
    • /
    • 2018
  • The purpose of this study is to classify and analyze the deconstruction phenomena expressed in contemporary knit fashion design, and to analyze the inner meaning of deconstruction based on certain characteristics. As a method of study, literature data for theoretical backgrounds, prior studies, and internet data were analyzed. The scope of this study was restricted to knitwear published in the world's four major collections (Milan, Paris, New York and London) from 2014 F/W to 2018 S/S. Based on prior studies, four concepts of deconstruction were derived: "$Diff{\acute{e}}reance$", "Intertextuality", "Intermeaning of Meaning", "Dis De Phenomenon". The results of the study were as follows: first, "$Diff{\acute{e}}reance$" refers to a transcendence of time and space. These expressions are discursive, unrealistic, and convey freedom through intent that deviates from rules and norms. Second, "Intertextuality" indicates a mixture of different texts, such as styles, materials, and items. These expressions deliver novelty with amusement, and can be entertaining depending on audience expectations. Third, "Intermeaning of Meaning" is accidental category - depending on how the wearer wears the clothing. -; accordingly, free and spontaneous creativity is an emerging trend in fashion. Fourth, the clothing was expressed in deformed and distorted form by the construction and destruction of the structure, a technique we describe as the "Dis De Phenomenon". In this concept, the sense of free design of young emotion appears along with the sense of purity and shock due to intentional inconsistency.

A modified RIO queue management scheme that reduces the bandwidth skew problem in Assured Service

  • Kim, hyogon;Park, Won-Hyoung;Saewoong Bahk
    • Proceedings of the Korean Information Science Society Conference
    • /
    • 1999.10c
    • /
    • pp.423-426
    • /
    • 1999
  • In offering a statistical end-to-end bandwidth guarantee service, typically called Assured Service, in Differentiated Serviced (Diff-Serv) framework, the biggest issue is its inconsistency. Larger profile TCP flows fail to achieve the guaranteed rate when competing with many smaller profile flows. This phenomenon, which we call "bandwidth skew", stems from the fact that larger profile flows take longer time to recover from the congestion window size backoff after a packet drop. Proposed solutions to this problem, therefore, are focused on modifying the TCP behavior. However, TCP modification is not practicable, mainly due to its large installation base. We look to other mechanisms in the Diff-Serv framework to find more realistic solutions. In particular, we demonstrate that RIO, the de facto standard packet differentiation mechanism used for Assured Service, also contributes to the bandwidth skew. Based on this new finding, we design a modified RIO mechanism called RI+O. RI+O uses OUT queue length in addition to IN and IN+OUT queue length to calculate OUT packet drop probability. We show through extensive simulation that RI+O significantly alleviates the bandwidth skew, expanding the operating regime for Assured Service.d Service.

  • PDF

Adenoid Cystic Carcinoma of the Breast: Diagnosis by Fine Needle Aspiration Cytology (유방의 선양 낭포성 암종 -세침흡인 세포검사로 진단된 1 예 보고-)

  • Lee, Dong-Wha;Jin, So-Young;Kim, Dae-Joong;Kwon, Kui-Hyang
    • The Korean Journal of Cytopathology
    • /
    • v.2 no.2
    • /
    • pp.160-167
    • /
    • 1991
  • Adenoid cystic carcinoma is a rare valiant of mammary cancer with better prognosis. The diagnosis is usually made by histologic examination of biopsy specimen. Recently, we have experienced a case of adenoid cystlc carcinoma initially diagnosed by fine needle aspiration cytology which revealed distinct cytologic features in a 45-year-old woman. Pink to red globules in the tumor cell clusters on Diff-Quik staining was a very helpful finding for cytologic diagnosis.

  • PDF

The Design of TC with WFQ for Effective Resource Sharing on Differentiated Service (Differentiated Service에서 공정한 자원 공유를 위한 WFQ 적용 TC 설계)

  • 장경성
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.41 no.2
    • /
    • pp.31-40
    • /
    • 2004
  • Diff-Serv(DS) is a mechanism by which network service providers can offer differing levels of network service to different traffic, in so providing quality of service(QoS) to their customers. Because this mechanism has been deployed just for fixed hosts with the Token Bucket mechanism according to AggF(Aggregate Flow) instead of each flow, DS can not suggest effective usability of traffic resources. In this paper, we use WFQ mechanism for traffic conditioner and scheduling method monitoring the AggF and the results will be used to control the next flows coming in TC. So it will control traffic rate dynamically and suggest efficient usability of bandwidth.

Scalable Internet Resource Reservation Mechanism (확장성 있는 인터넷 자원 예약 기법)

  • 박주영;고석주;강신각
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2002.11a
    • /
    • pp.610-613
    • /
    • 2002
  • To improve quality of service(QoS) in the current Internet, various QoS providing mechanisms such as RSVP, DiffServ have been proposed. In this paper we propose a more simple but more scalable mechanism which can guarantee end-to-end QoS. The proposed mechanism can provide scalability by minimizing the state information which is needed by router to reserve network resources. Using sender-initiated & soft-state resource reservation, a router does not need to keep the backward data path like RSVP. In this paper we illustrate the proposed resource reservation mechanism with network topology and signaling.

  • PDF