Paul P. Wang

Duke University | DU

Steels with varying chromium contents are widely used in steam turbine components and have been introduced steadily in the last decades. The initial aim in the development of such steels is to achieve high performance in creep resistance. Due to the fluctuations of electrical power demand nowadays, power plants are increasingly forced to run at var...

The Duke storage ring is a dedicated driver for the storage ring based oscillator free-electron lasers (FELs), and the High Intensity Gamma-ray Source (HIGS). It is operated with a beam current ranging from about 1 mA to 100 mA per bunch for various operations and accelerator physics studies. High performance operations of the FEL and gamma-ray sou...

Nowadays, fossil power plants are increasingly required to start up and shut down frequently due to the flexibility of electrical power demand. Thermomechanical fatigue (TMF) induced by temperature transients with superimposed creep on the heated surfaces of components leads to a significant reduction of lifetime. In this paper, the influence of te...

To enable the Duke storage ring FEL to operate in VUV with adequate gain, a major storage ring upgrade was carried out in 2012 to install two additional helical FEL wigglers with a wiggler switchyard system. Using the switchyard, a quick changeover can be made between two planar OK-4 wigglers and two helical OK-5 wigglers in the middle of the FEL s...

Analysis of the influence of thermal transients during steam turbine start-up and shut-down, with superimposed creep loading, not only affects the safe operation of power plant but also economic and environmental concerns. As a powerful tool, constitutive material models allow a direct coupling to the finite element method to simulate components wi...

There are much more publications in open literature on the topic of linguistic variables as compared with Computing With Words (CWW). This paper intends to change that situation by demonstrating the feasibility of a working system. In order to accomplish this goal, a very focused example of an insurance evaluation system, no matter how rudimentary,...

Power system restructuring and renewable energy resources are the cause of many problems regarding system reliability management. Because of intermittent behavior of renewable resources and segregation of generation system into different Generation Companies (Gencos), conventional techniques cannot be directly used in the reliability evaluation of...

Electron beam coupled-bunch instabilities can limit and degrade the performance of storage ring based light sources. A longitudinal feedback system has been developed for the Duke storage ring to suppress multi-bunch beam instabilities which prevent stable, high-current operation of the storage ring based free-electron lasers (FELs) and an FEL driv...

Traditional mathematics is the language of precision. Statements are either true or false. But, in reality there are few things that are truly simply true or false. Life is full of shades of grey. Capturing these shades of grey has been problematic using traditional mathematics. Mathematics can model the uncertainty itself but rarely incorporates i...

Power system restructuring with high renewable energy penetration has created some new problems for reliability evaluation. One of the problems is the large computation time due to the increased number of renewable generators. In this regard, the reliability network equivalent techniques have been introduced to simplify calculation. These technique...

This paper reports some novel approach on linguistic logic with our intention to realize CWW, Computing With Words, via a simple example which consists of only five words. As a by product, this simple example of the linguistic logical system may serve as a mathematical model, modeling the degree of truthfulness in daily usage. The five words set of...

Decision Making is a core area of different research pursuits such as engineering, both theory and practice, management, medicine and alike. Issues related to this area have been traditionally handled either by deterministic or by probabilistic approaches. The first one completely ignores uncertainty, while the second one assumes that any uncertain...

Although modern scientific and technological advances derive computational power primarily from the classical evidence-based bottom-up cognition as founded by Greek philosopher Aristotle in his philosophy of science with a bivalent logic, the classical cognition, however, has met stiff challenges during the last few decades because of uncertainty f...

The beam position monitor system of the Duke storage ring has been in operation since 1998. Recently, by injecting at higher energy with a booster synchrotron, the single bunch current threshold is much more increased. The high peak voltage associated with high single-bunch current degrades the performance of the BPM system and can potentially dama...

First operational experience has been gained with the linac and booster diagnostic system during the commissioning of the booster synchrotron at Duke University. The booster was designed and developed as an injector for the storage ring as a part of the High Intensity Gamma-ray Source (HIGS) upgrade of Duke FEL storage ring. Booster beam instrument...

A betatron tune measurement system is one of the most important diagnostic tools for any circular accelerator. For the commissioning of a booster synchrotron newly developed for top-off injection into the Duke storage ring, a versatile tune measurement system employing a network analyzer, a short stripline kicker, a space filter and a photomultipli...

This paper presents an effective method based on genetic algorithm for optimizing the rendering quality in image-based painterly rendering. Based on a multi-level evolutionary approach, the proposed method produces, for a variety of input images, results that are better in a statistically significant way than previous methods.

Given the trapezoid diagram, the problem of finding the minimum cardinality connected dominating set in trapezoid graphs was solved in O(m+n) time [Y.D. Liang, Steiner set and connected domination in trapezoid graphs, Inform. Process. Lett. 56 (2) (1995) ...

This paper presents some novel theoretical results as well as practical algorithms and computational procedures on fuzzy relation equations (FRE). These results refine and improve what has already been reported in a significant manner. In the previous paper, the authors have already proved that the problem of solving the system of fuzzy relation eq...

A Monte Carlo simulation technique evaluates the reliability indices of restructured power systems with a hybrid market. A model for optimal transaction curtailment for a contingency state in a hybrid market is developed to incorporate the changes brought about by deregulation. The objective of the contingency optimal transaction curtailment for ea...

This paper outlines a data mining approach to the analysis and prediction of the trend of stock prices. The approach consists of three steps, namely, partitioning, analysis and prediction. A commonly used k-means clustering algorithm is used to partition stock price time series data. After data partition, linear regression is used to analyse the tr...

Computational intelligence (CI), as an alternative to statistical and econometric approaches, has been applied to a wide range of economics and finance problems in recent years, for example to price forecasting and market efficiency. This book contains research ranging from applications in financial markets and business administration to various ec...

Computational intelligence (CI), as an alternative to statistical and econometric approaches, has been applied to a wide range of economics and finance problems in recent years, for example to price forecasting and market efficiency. This book contains research ranging from applications in financial markets and business administration to various ec...

This paper describes a technique for clustering homogeneously distributed data in a peer-to-peer environment like sensor networks. The proposed technique is based on the principles of the K-Means algorithm. It works in a localized asynchronous manner ...

The goals of this paper are threefold: (1) to introduce SORE to the biocontrol systems research community, describe how it works and explain why it could be an successful basic building block for a biocontrol system, (2) to present the basic characteristics of SORE and Boolean networks (BN) in a modern control language, with emphasis on their mathe...

In this paper we have introduced a class of decision rules related to simple majority, by considering individual intensities of preference. These intensities will be shown by means of linguistic labels. In order to compare the amount of opinion obtained ...

At the Free Electron Laser (FEL) Laboratory of Duke University, there is an S-band linac based Mark III FEL facility which can supply coherent FEL photon in the in-frared wavelength range. To supply high quality electron beams and to have excellent pulse structure, we installed an S-band RF gun with a Lanthanum Hexaboride (LaB 6) sin-gle crystal ca...

A scheme that registers and aligns digital image lesions of psoriasis within and between sessions is proposed. Lesions to be tracked are found under the assumption of being the object of largest size in thematic maps produced by a two-step hierarchical ...

In a deregulated power system, spinning-reserve (SR) can be allocated to different ancillary service providers at different locations based on supplier bids and customer choices in terms of reliability and the related cost. The paper investigates the impacts of spinning-reserve allocations on system reliability and cost. A hybrid SR allocation meth...

Feed-forward neural networks used for pattern classification generally have one input layer, one output layer and several hidden layers. The hidden layers in these networks add extra non-linearity for realization of precise functional mapping between the input and the output layers, but semantic relations of the hidden layers with their predecessor...

Power system restructuring has changed the mechanism of system reliability management and electricity pricing. The electricity price and supply point reliability are correlated due to customer participation in market trading in the new environment. A new technique used to determine both nodal prices and nodal reliability indices of deregulated powe...

In this paper, a new approach for time series forecasting is presented. The forecasting activity results from the interaction of a population of experts, each integrating genetic and neural technologies. An expert of this kind embodies a genetic classifier ...

In a bilateral contracts market while selecting contracts to meet their reliability requirements, probability distributions of load point reliability indices considering multi-bilateral contracts with Gencos can provide useful information for the customers. This paper utilizes the modeling of each bilateral contract as an ETMG (equivalent time vary...

According to the progress of an information-oriented society, more human friendly systems are required. Such systems can be implemented by a kind of much more intelligent algorithms. In this paper we propose the possibility of the implementation of an intelligent algorithm from gene behavior of human beings, which has some properties such as self o...

This paper presents a time sequential Monte Carlo simulation technique to evaluate customer load point reliability in multi-bilateral contracts market. The effects of bilateral transactions, reserve agreements, and the priority commitments of generating companies on customer load point reliability have been investigated. A generating company with b...

Since rule induction methods generate rules whose lengths are the shortest for discrimination between given classes, they tend to generate rules too short for medical experts. Thus, these rules are difficult for the experts to interpret from the viewpoint ...

In a deregulated power system, spinning reserve can be allocated to different ancillary service providers at different locations based on the supplier bids and customer choices on the reliability levels required. Different allocations of spinning reserve are expected to create different impacts on the reliability of the physical power system. When...

In a deregulated power system customers have the freedom to choose their reliability. They can purchase spinning reserve directly from electric power providers. In this case, an individual customer is concerned more with its own load point reliability rather than with the system reliability. This paper introduces bulk load point (BLP) well-being in...

In deregulated power systems spinning reserve (SR) can be allocated to different ancillary service providers at different locations based on supplier bids and customer choices on reliability. This paper investigates the impact of transmission line failures using a cost/risk-based spinning reserve allocation method (CRSRAM). The proposed method prov...

Due to the ability to handle specific characteristics of economics and finance forecasting problems like e.g. non-linear relationships, behavioral changes, or knowledge-based domain segmentation, we have recently witnessed a phenomenal growth of the application of computational intelligence methodologies in this field. In this volume, Chen and Wang...

This paper presents a technique to manage the system reserve based on customer load point reliability in a bilateral power market. The reliability network equivalent techniques are used to represent each market player in a power market. The equivalent assisting unit approach is used to determine the reliability model of a market player considering...

Power system deregulation has introduced some fundamental problems regarding system reliability management. This paper presents a technique used for the reliability evaluation of restructured power systems. A reliability model for each market player in a restructured power system is introduced in which a generation company is represented by an equi...

As part of the recent Duke storage ring hardware upgrade (2001-2002), a power supply improvement program was put in place to bring all major DC supplies to their specifications. In carrying out this program, power supplies have been modified, tuned, and thoroughly tested. In its actual operation configuration, each power supply was subject to exten...

Stable and reliable storage ring operation critically depends on the orbit stability. At Duke, an orbit stability program is well under way to achieve the high level of orbit performance necessary for reliable free electron laser (FEL) and gamma-ray operation. Progress has been made to reduce the current dependency of BPM readings via choice of cab...

In a well-designed vertically integrated utility, it is relatively easy to meet the load point reliability with sufficient installed capacity. The reliability indices are calculated making use of all the installed generators and the expected load. The situation in an hourly spot market is different because the generating companies are under no obli...

Conventional distribution system reliability evaluation is focused on the determination of average loadpoint andsystem reliability indices. The actual annual reliability performance of a distribution system is, however, a random variable with an associated probability distribution. This paper illustrates the development of the average reliability i...

The Fuzzy Predictive Earth Analysis Constrained by Heuristics (fuzzy PEACH) project is divided into three phases. Phase one uses fuzzy logic to help quantify 2D, high-resolution seismic interpretation, a linguistic-laden and sometimes subjective descriptive process in terms of membership. In addition, it is hypothesized that these fuzzy-coded, ling...

Recent advances in high-throughput molecular biology has motivated in the field of bioinformatics the use of network inference algorithms to predict causal models of molecular networks from correlational data. However, it is extremely difficult to evaluate the effectiveness of these algorithms because we possess neither the knowledge of the correct...

Motivation: Searches for near exact sequence matches are performed frequently in large-scale sequencing projects and in comparative genomics. The time and cost of performing these large-scale sequence-similarity searches is prohibitive using even the fastest of the extant algorithms. Faster algorithms are desired.

Economic systems are characterized by uncertainty in their dynamics. This increasing uncertainty is likely to promote bad decisions that can be costly in financial terms. This makes forecasting of uncertain economic variables an instrumental activity in any organization. This paper takes the hotel industry as a practical application of forecasting...

Current status of Mark III free electron laser and its upgrades are presented

At the Duke Free Electron Laser (FEL) Laboratory, there are two FEL machines: the Mark III infrared FEL and the OK-4/Storage Ring, which produces an UV and XUV laser beam as well as gamma rays via Compton backscattering. The recent status of Mark-III machine is described in another paper. Here we will concentrate on the new development of the OK-4/...

This paper proposes a three-level hierarchical mathematical model for intelligent and complex systems. Motivation, background, rationale, interpretations and potential applications are presented. Different visions from different schools of thought in various academic disciplines are illustrated in a block diagram. The concept of “soft-modeling”, re...

This article presents a literature review of the current state of staff scheduling, in particular nurse scheduling. In current health care service, the critical problem in nurse scheduling in a hospital is how to determine day-to-day shift assignments of each nurse for a period of time in a way that satisfies the given requirements of a hospital. A...

In current health care service, it's important to minimize staff idle time and maintain a high utilization rate of the medical facilities. More and more hospitals, however, recognize waiting is a universal and serious problem for patients. The critical problem in medical scheduling is how to keep the balance of all these factors. Computer simulatio...

In this paper we present the result of the deep-UV lasing with the OK-4/Duke storage ring FEL. The OK-4 FEL was initially commissioned at Duke Free Electron Laboratory in November 1996 followed by a yearlong shutdown. After re-establishing the storage ring operation in early 1998, the OK-4 FEL lasing was demonstrated in the wavelength range of 226–...

In this paper we present the result of the deep-UV lasing with the OK-4/Duke storage ring FEL. The OK-4 FEL was initially commissioned in the near-UV at Duke Free Electron Laboratory in November, 1996 followed by a year-long shutdown. After re-establishing the storage ring operation in early 1998, the OK-4 FEL lasing was demonstrated in the wavelen...

Diagnostic problems are proposed to be solved via the pattern recognition approach. The main example has been motivated by economic macro modelling, hence a reference model approach is adopted. The dynamic systems under consideration are assumed to be linear in three case studies and nonlinear in one case study. All four case studies illustrate the...

In this thesis we model and analyze complex distributed control systems known as control networks. We discuss a class of hybrid systems called switched systems or Witsenhausen systems. We study the existence of a solution to the state trajectory equation as well as conditions for global existence of solutions. We also present a discussion about the...

INTRODUCTION The Mark III electron linear accelerator underwent many incarnations at the Stanford High Energy Physics Laboratory following its initial construction beginning in 1949. A description of the history up to the mid 1960s is given in reference [1]. During 1963 and 1964 the Mark III was reconfigured to its final form using new constant-gra...

The OK-4/Duke storage ring FEL was commissioned in November 1996 and demonstrated lasing in the near UV and visible ranges (345 - 413 nm). The OK-4 is the first storage ring FEL with the shortest wavelength and highest power for UV FELs operating in the United States. During one month of operation we have performed preliminary measurements of the m...

this paper, we present a complete design framework for an adaptive multiple agent fuzzy constraint-based controller (MAFCC) based on fuzzy penumbra constraint processing in each fuzzy constraint subnetwork collaborating with a connected constraint network and its corresponding semantic modeling in a first-order predicate calculus (FOPC) language, w...

This paper introduces a novel fuzzy logic controller design methodology based on the theory of fuzzy constraint network. Despite the successes of rule-based fuzzy logic controller design techniques, this approach represents only a very special case of the expressive power of the first order predicate calculus (FOPC). The notion of "constraint" has...

A complete design framework for a fuzzy constraint-based controller based on fuzzy-constraint processing and its semantics and relationship to fuzzy logic is presented. In this paper, the concept of “fuzzy constraints” in problem solving is introduced, and some basic definitions of fuzzy-constraint processing in a constraint network and its semanti...

In this paper, we shall introduce the notion of a rough subgroup with respect to a normal subgroup of a group, and give some properties of the lower and the upper approximations in a group. Also, we will discuss a rough subgroup with respect to a t-level subset of a fuzzy normal subgroup.

This paper summarizes the research results dealing with washer and nut taxonomy and knowledge base design, making the use of fuzzy methodology. In particular, the theory of fuzzy membership functions, similarity matrices, and the operation of fuzzy inference play important roles. A realistic set of 25 washers and nuts are employed to conduct extens...

Without Abstract

Intelligent control has become an issue of primary importance in modern process automation as it provides the prerequisites for the task of fault detection. The ability to detect the faults is essential to improve reliability and security of a complex control system. Parameter estimation methods, state observation schemes, statistical likelihood ra...

This paper presents the classification of fuzzy dynamic systems and fuzzy linguistic controllers into standard types (TYPE 1 through TYPE 7). The need and utility value behind this classification are given. Hopefully, this classification will lead to new designs and improve the performance of control systems. 1 Introduction Human operators have a r...

Fault diagnosis has become an issue of primary importance in modern process automation as it provides the prerequisites for the task of fault detection. The ability to detect the faults is essential to improve reliability and security of a complex control system. Parameter estimation methods, state observation schemes, statistical likelihood ratio...

Intelligent control has become an issue of primary importance in modern process automation as it provides the prerequisites for the task of fault detection. The ability to detect the faults is essential to improve reliability and security of a complex control system. In this paper, we describe a completed feasibility study demonstrating the merit o...

The commissioning of the 1 GeV Duke Storage Ring began in November, 1994 with the demonstration of injection, storage and ramping to 1 GeV at the first attempt. The ring is now operational. The Duke project is unique in that the storage ring and linac were designed, constructed and commissioned by a small new University laboratory, operating on a l...

In the early 1960s, the Mark III accelerator at the Stanford High Energy Physics Laboratory was used as the prototype test-bed for the SLAC two-mile accelerator. In the mid 1980s, the accelerator was dismantled and a large part of it was transported to the Duke University Free-Electron Laser Laboratory to form the basis of the injector for the 1-Ge...

Despite the successes of rule-based fuzzy logic control, this paradigm offers only a small part of the expressive competence of the first-order predicate calculus (FOPC). In addition, because constraints represent the requirements that the artifact being designed must satisfy, the design can be viewed as exploring alternatives in a solution space b...

Fault diagnosis has become an issue of primary importance in modern process automation as it provides the prerequisites for the task of fault detection. The ability to detect the faults is essential to improve reliability and security of a complex control system. In this paper, the authors describe a completed feasibility study demonstrating the me...

Genetic Algorithms (GAs) are utilized to optimize the three parameters of classical PID controllers for nonlinear processes. The concept and working principle of GAs are introduced and compared with those of traditional optimization methods. A simple GA to solve this nonlinear optimization problem is designed based on the GA theory and the authors'...

In this paper, a modified Elman neural network (1990) is utilized to identify industrial processes. The basic structure of the Elman network is introduced and one of its modified versions is presented. A specific learning algorithm is developed which optimizes not only the feedforward but also the self-feedback connections of such partially recurre...

This paper presents the classification of fuzzy dynamic systems and fuzzy linguistic controllers (FLC) into standard types (TYPE 1 through TYPE 7). The need, utility value, and the logic behind this classification are given. The proposed classification is the result of studying many known examples of FLC applications. The impact of this classificat...

A specific fuzzy controller is developed for the regulation of a pH neutralization process. This fuzzy controller is primarily that of the fuzzy PD control structure but simultaneously enhanced by a normal integrator and a Smith predictor. The model of the pH neutralization process considered has highly nonlinear characteristics with time delay. Th...

Genetic Algorithms (GAs) are utilized to optimize the three parameters of classical PID controllers for nonlinear processes. The concept and working principle of GAs are introduced and compared with those of traditional optimization methods. A simple GA to solve this nonlinear optimization problem is designed based on the GAs theory and the authors...

This paper addresses three main issues, which are somewhat interrelated. The first issue deals with the classification or types of fuzzy controllers. Careful examination of the fuzzy controllers designed by various engineers reveals distinctive classes of fuzzy controllers. Classification is believed to be helpful from different perspectives. The s...

Novel algorithms for image enhancement, filtering and edge detection using the fuzzy logic approach are proposed. An enhancement technique based on various combinations of fuzzy logic linguistic statements in the form of if-then rules modifies the image contrast and provides a linguistic approach to image enhancement. A fuzzy filtering technique ba...

We present some computational characteristics of back-error propagation (BEP) networks in processing graded patterns that are otherwise indistinguishable in binary (or bipolar) representations. We address the problem of mapping l-of-m unit gradients with interunit activation profile d to n classes, where maximum noise amplitude of ϵ is permitted wi...

Genetic algorithms (GAs) are utilized to build an optimization mechanism to refine the rule base of fuzzy proportional-integral-derivative (PID) controllers. The essential control law of fuzzy PID controllers is formulated by means of fuzzy set theory and the classical PID principle. An optimization scheme for fuzzy PID controllers is presented usi...

Advanced genetic algorithms (GAs) are used to automatically carry out the fine-tuning of the parameter settings of classical PID (proportional plus integral plus derivative) controllers. The basic concept and working principle of GAs are introduced and compared with those of traditional optimization techniques. An advanced GA which can rapidly opti...

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Current robotic taction applications have largely been limited to presence/absence detection via “simple touch” or the use of force-torque sensors. Although artificial tactile sensors have been developed, advanced industrial applications have not matured due to time and resource constraints in manufacturing environments to develop and maintain appl...

A fuzzy PID controller is proposed replacing the widely-used classical PID controllers assembled at all joints of a robot arm. The fuzzy PID control algorithm is outlined using fuzzy set theory. The design techniques are developed based on the linguistic phase plane approach. The heuristic rules of synthesis are summarized into a rule-based expert...

Optimal linear regulators with steady-state trajectory insensitivity are designed based on a quadratic performance index which includes a time-multiplied quadratic function of the trajectory sensitivity vector. Under the linear feedback control law, the performance index is evaluated by means of the integral transformation. With the aid of the Hami...

We study the feasibility of adaptive pattern recognition of robotic tactile impressions using connectionist models. This paper presents interim simulation results of coupled back-error propagation (BEP) networks that (i) extract relative gradient features via data compression, (ii) clusters families of grey-scale patterns constrained by geometry, s...

A class of linguistic controllers is derived using the combination of classical PID (proportional-integra l -derivative) control ideas and fuzzy set theory. Six different types of such controllers are proposed and their basic characteristics investigated and discussed. A fuzzy scaling technique is suggested for the reduction of off-line computation...

This paper presents an overview of an inspection system called Automated Robotic Visual Inspection System (ARVIS). The ARVIS system concept, hardware components, work-cell, and calibration and inspection procedures are described. Application of ARVIS is currently focused on inspecting precision industrial parts, specifically, traveling wave tube (T...