Browsing by Author "Yang, MH"

Now showing 1 - 14 of 14

A Borrow-and-Return model to reduce client waiting time for broadcasting-based VOD services
(2003-06-01)
Yang, MH
;
Chang, CH
;
Tseng, YC
;
資訊工程學系
;
Department of Computer Science
One way to broadcast a popular video is to use multiple channels, each broadcasting a portion of the video periodically. Among the many schemes falling in this category, this paper focuses on several representative schemes (such as FB [15], [18], Pagoda [22], [24], and RFS [26]), which all share a FSFC property by repeatedly broadcasting the First Segment of the video on the First Channel. We propose a general Borrow-and-Return model that can be immediately applied to any scheme owning the FSFC property to reduce the viewer's waiting time without increasing the number of channels required. Given a group of videos, the basic idea is to lend the free time slots of videos without viewers to those videos with viewers to speedup the latter's transmission. By so doing, some bandwidth may be vacated by the borrowing videos to benefit others' transmission. Effectiveness of this model is analyzed by applying it to the FB scheme.
A case study on the multistage IC final testing scheduling problem with reentry
(2004-04-18)
Pearn, WL
;
Chung, SH
;
Chen, AY
;
Yang, MH
;
工業工程與管理學系
The integrated-circuit final testing scheduling problem (ICFTSP) with reentry is a variation of the complex flow-shop scheduling problem, which is also a generalization of the classical reentrant flow batch process problem, and the identical parallel machine problem. In this paper, we present a case study on the ICFTSP with reentry, which is taken from a final testing shop floor in an integrated circuit manufacturing factory. For the case investigated, the jobs are clustered by their product types, which must be processed on groups of parallel machines at various process stages following the manufacturing sequence, which must be completed before the due dates. The job processing time depends on the product type, and the machine setup time is sequentially dependent on the orders of jobs processed. The objective is to schedule jobs without violating all constraints, while the total machine workload is minimized. Since the ICFTSP has reentry characteristic, and involves job processing precedence, serial-processing stage, batch-processing stage, job clusters, job-cluster dependent processing time, due dates, machine capacity, and sequence dependent setup time, it is more difficult to solve than the classical flow-shop scheduling problem. We present three fast network algorithms to efficiently solve the ICFTSP with reentry and provide a performance comparison between the three algorithms on eight test problems. (C) 2003 Elsevier B.V. All rights reserved.
A case study on the wafer probing scheduling problem
(2002-01-01)
Pearn, WL
;
Chung, SH
;
Yang, MH
;
工業工程與管理學系
;
Department of Industrial Engineering and Management
The wafer probing scheduling problem (WPSP) is a practical generalization of the classical parallel-machine scheduling problem, which has many real-world applications, particularly, in the integrated circuit (IC) manufacturing industry. In this paper, a case study on the WPSP is presented, which is taken from a wafer probing shop floor in an IC manufacturing factory. For the WPSP case investigated, the jobs are clustered by their product types, which are processed on groups of identical parallel machines and must be completed before the due dates. The job processing time depends on the product type, and the machine setup time is sequentially dependent on the orders of jobs processed. The objective in this case is to seek a probing job schedule with minimum total machine workload. Since the WPSP case investigated involves constraints on job clusters, job-cluster dependent processing time, due dates, machine capacity, and sequentially dependent setup time, it is more difficult to solve than the classical parallel-machine scheduling problem. The WPSP is formulated as an integer programming problem and the problem solved using the powerful CPLEX with effective implementation strategies. An efficient solution procedure to solve the WPSP near-optimally is proposed.
A lab-scale digital acoustic emission system for source location
(1999-07-01)
Yang, MH
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Chou, CP
;
機械工程學系
;
Department of Mechanical Engineering
A Stop-or-Move Mobility model for PCS networks and its location-tracking strategies
(2003-07-21)
Tseng, YC
;
Chen, LW
;
Yang, MH
;
Wu, JJ
;
資訊工程學系
This paper considers the location-tracking problem in PCS networks. Solutions to this problem in fact highly depend on the mobility patterns of mobile subscribers [ACM DIAL-M (1999) 72]. In the literature, many works have assumed a simple random walk model, where mobile subscribers always stay in a roaming state and can move in any direction with equal probability. In this paper, we propose a new Stop-or-Move Mobility (SMM) model, which is characterized by the following features: 'transition between stop and move', 'infrequent transition', 'memory of roaming direction', and 'oblivious in different moves'. Based on this mobility model, a static and an adaptive location-tracking Scheme are developed. The schemes only need to keep very little information for each user. Analyses and simulations are provided, which show that the proposed schemes are quite prospective. (C) 2003 Elsevier Science B,V. All rights reserved.
Algorithms for the wafer probing scheduling problem with sequence-dependent set-up time and due date restrictions
(2004-11-01)
Pearn, WL
;
Chung, SH
;
Yang, MH
;
Chen, YH
;
交大名義發表
In this paper, we consider the wafer probing scheduling problem (WPSP) to sequence families of jobs on identical parallel machines with due date restrictions. The machine set-up time is sequentially dependent on the product types of the jobs processed on the machine. The objective is to minimize the total machine workload without violating the machine capacity and job due date restrictions. The WPSP is a variation of the classical parallel-machine scheduling problem, that can be transformed into the vehicle-routing problem with time windows (VRPTW). One can therefore solve the WPSP efficiently using existing VRPTW algorithms. We apply four existing savings algorithms presented in the literature including sequential, parallel, generalized, and matching based savings, and develop three modifications called the modified sequential, the compound matching based, and the modified compound matching-based savings algorithms, to solve the WPSP. Based on the characteristics of the wafer probing process, a set of test problems is generated for testing purposes. Computational results show that the three proposed modified algorithms perform remarkably well.
An investigation of tank bottom leak detection using acoustic emission
(1998-07-01)
Yang, MH
;
Chou, CP
;
機械工程學系
;
Department of Mechanical Engineering
To investigate the acoustic emission (AE) bursts from leakage through a hole, experiments were conducted on a small test tank under different conditions. When neither backfill material nor air was involved, AE bursts were detected exactly at or very close to the hole. The instantaneous abrupt pressure change of fluid at the hole, frequently associated with the unsteady flow around the hole, is suggested as the origin of these AE bursts. On the other hand, the fluid-air or fluid-sand interaction can also produce AE bursts, but the occurrence sites and signal characteristics are different. Leakage at higher water level results in stronger AE bursts, and a larger leak hole produces move bursts. The leak rate alone is not a proper index as to whether AE bursts will occur or not. In many cases of the tests, the occurrence of AE bursts from leakage cannot be fully explained by the present knowledge of turbulence.
Data broadcasting and seamless channel transition for highly demanded videos
(2001-05-01)
Tseng, YC
;
Yang, MH
;
Hsieh, CM
;
Liao, WH
;
Sheu, JP
One way to broadcast a popular video is to use a number of dedicated channels, each responsible for broadcasting some portion of the video periodically in a predefined way. The stress on channels can be alleviated, and new viewers do not have to wait long to start their playback, Many approaches falling in this category have been proposed, One such scheme that interests us is the fast broadcasting (FB) scheme, which can broadcast a video using k channels by incurring at most O(D/2(k)) waiting time on new-coming viewers, where D is the length of the video. In this paper, we consider a set of videos, each being broadcast by the FB scheme, Since the levels of demands on these videos may change by time, it is sometimes inevitable to change the numbers of channels assigned to some videos. We propose a novel seamless channel transition enhancement on top of the FB scheme to dynamically change the number of channels assigned to a video on-the-fly. Clients currently viewing this video will not experience any disruption because of the transition. A channel allocation scheme is also proposed based on the arrival rates of videos to minimize the average waiting experienced by all viewers, From the system manager's point of view, the enhancement will make the FB scheme more attractive.
Minimizing the total machine workload for the wafer probing scheduling problem
(2002-02-01)
Pearn, WL
;
Chung, SH
;
Yang, MH
;
工業工程與管理學系
;
Department of Industrial Engineering and Management
The Wafer Probing Scheduling Problem (WPSP) is a practical generalization of the parallel-machine scheduling problem, which has many real-world applications, particularly, in the Integrated Circuit (IC) manufacturing industry. In the wafer probing factories, the jobs are clustered by their product types, which must be processed on groups of identical parallel machines and be completed before the due dates. The job processing time depends on the product type, and the machine setup time is sequentially dependent on the orders of jobs processed. Since the wafer probing scheduling problem involves constraints on job clusters, job-cluster dependent processing time, due dates, machine capacity, and sequentially dependent setup time, it is more difficult to solve than the classical parallel-machine scheduling problem. In this paper, we consider the WPSP and formulate the WPSP as an integer programming problem to minimize the total machine workload. We demonstrate the applicability of the integer programming model by solving a real-world example taken from a wafer probing shop floor in an IC manufacturing factory.
Multi-node multicast in multi-dimensional wormhole tori and meshes with load balance
(2002-11-01)
Yang, MH
;
Tseng, YC
;
Jian, MS
;
資訊工程學系
;
Department of Computer Science
This paper considers the multi-node multicast problem in a multi-dimensional wormhole-routed torus/mesh, where there is an arbitrary number of source nodes, each intending to multicast a message to an arbitrary set of destinations. This problem requires a large amount of bandwidth and, thus, typically incurs heavy contention and congestion. Evenly balancing the traffic load around the network is critical to achieving good performance. We show how to use a network-partitioning approach to achieve this goal. Simulation results show significant improvement over existing results in 3D tori and meshes. This work is an extension of our earlier work [22] from 2D tori/meshes to higher dimensional ones.
Recursive frequency-splitting scheme for broadcasting hot videos in VOD service
(2002-08-01)
Tseng, YC
;
Yang, MH
;
Chang, CH
;
資訊工程學系
;
Department of Computer Science
One way to broadcast a popular/hot video is to let multiple users share a few channels. The stress on the scarce channels can be alleviated without sacrificing viewer waiting time. One common approach is to partition the video into fixed-length segments, which are broadcast on several channels periodically. Two representative approaches are the Fast Broadcasting scheme and the PAGODA scheme, which can broadcast a video using k channels by having new viewers wait no longer than Theta(D/2(k)) and Theta(D/5(k/2)) time, respectively, where D is the length of the video. In this paper, we propose a new scheme, called Recursive Frequency Splitting (RFS), that significantly improves on existing schemes in terms of viewer waiting time. Some lower bounds on the viewers' waiting time are also developed.
Tank bottom leak detection using AE: on the mechanism of the occurrence of AE bursts due to leakage
(1998-08-01)
Yang, MH
;
Chou, CP
;
機械工程學系
;
Department of Mechanical Engineering
During leak and bubble tests on a test tank, AE bursts are frequently detected along with the pressure change due to the unsteady flow close to the hole. A model, based on a postulated unsteady state and concentrating on the relationship between. the flow and the velocity gradient, is presented to explain the occurrence of AE burst. It is suggested that only the stream that is crossing the steep velocity gradient near the hole edge will produce strong AE bursts. An unsteady flow is considered favourable for such stream to occur therefore producing more AE bursts.
The integrated circuit packaging scheduling problem (ICPSP): A case study
(2005-09-01)
Pearn, WL
;
Chung, SH
;
Yang, MH
;
Chen, CY
;
工業工程與管理學系
The integrated-circuit-packaging scheduling problem (ICPSP) is a variation of the flexible flow-shop scheduling problem, which is also a generalization of the classical flow-shop and the identical parallel-machine problems. In this paper, we present a case study on the ICPSP. For the ICPSP we investigate, the jobs are clustered by their product types, which must be processed on groups of machines at various process stages following the manufacturing sequence, and be completed before the due dates. The job processing time depends on the product type, and the machine setup time is sequentially dependent on the orders of jobs processed. We present two efficient solution procedures to solve the ICPSP case. We generate a set of 11 ICPSP problems, which involve various setup time, processing time, and due date factors. The proposed savings approaches are shown to perform efficiently in solving the ICPSP. Significance: The integrated-circuit-packaging scheduling problem (ICPSP) is a practical but complex scheduling problem, which has many real world applications. The proposed approaches show the superiority to the traditional dispatch rules and solve the ICPSP efficiently.
The wafer probing scheduling problem (WPSP)
(2002-08-01)
Pearn, WL
;
Chung, SH
;
Yang, MH
;
工業工程與管理學系
;
Department of Industrial Engineering and Management
The wafer probing scheduling problem (WPSP) is a variation of the parallel-machine scheduling problem, which has many real-world applications, particularly, in the integrated circuit (IC) manufacturing industry. In the wafer probing factories, the jobs are clustered by their product types, which must be processed on groups of identical parallel machines and be completed before the due dates. Further, the job processing time depends on the product type, and the machine setup time is sequence dependent on the orders of jobs processed. Since the wafer probing scheduling problem involves constraints on job clusters, job-cluster dependent processing time, due dates, machine capacity, and sequence dependent setup time, it is more difficult to solve than the classical parallel-machine scheduling problem. In this paper, we formulate the WPSP as an integer programming problem. We also transform the WPSP into the vehicle routing problem with time windows (VRPTW), a well-known network routing problem which has been investigated extensively. An illustrative example is given to demonstrate the proposed transformation. Based on the provided transformation, we present three efficient algorithms to solve the WPSP near-optimally.