• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.35 no.3
• /
• pp.52-61
• /
• 2012

The design method for cumulative sum (CUSUM) control charts, which can be robust to autoregressive moving average (ARMA) modeling errors, has not been frequently proposed so far. This is because the CUSUM statistic involves a maximum function, which is intractable in mathematical derivations, and thus any modification on the statistic can not be favorably made. We propose residual-based robust CUSUM control charts for monitoring autocorrelated processes. In order to incorporate the effects of ARMA modeling errors into the design method, we modify parameters (reference value and decision interval) of CUSUM control charts using the approximate expected variance of residuals generated in model uncertainty, rather than directly modify the form of the CUSUM statistic. The expected variance of residuals is derived using a second-order Taylor approximation and the general form is represented using the order of ARMA models with the sample size for ARMA modeling. Based on the Monte carlo simulation, we demonstrate that the proposed method can be effectively used for statistical process control (SPC) charts, which are robust to ARMA modeling errors.

• Industrial Engineering and Management Systems
• /
• v.9 no.3
• /
• pp.227-241
• /
• 2010

A memory module industry's supply chain usually consists of multiple manufacturing sites and multiple distribution centers. In order to fulfill the variety of demands from downstream customers, production planners need not only to decide the order allocation among multiple manufacturing sites but also to consider memory module industrial characteristics and supply chain constraints, such as multiple material substitution relationships, capacity, and transportation lead time, fluctuation of component purchasing prices and available supply quantities of critical materials (e.g., DRAM, chip), based on human experience. In this research, a directed graph-based supply network planning (DGSNP) model is developed for memory module industry. In addition to multi-site order allocation, the DGSNP model explicitly considers production planning for each manufacturing site, and purchasing planning from each supplier. First, the research formulates the supply network's structure and constraints in a directed-graph form. Then, a proposed genetic algorithm (GA) solves the matrix form which is transformed from the directed-graph model. Finally, the final matrix, with a calculated maximum profit, can be transformed back to a directed-graph based supply network plan as a reference for planners. The results of the illustrative experiments show that the DGSNP model, compared to current memory module industry practices, determines a convincing supply network planning solution, as measured by total profit.

• Steel and Composite Structures
• /
• v.20 no.1
• /
• pp.205-225
• /
• 2016

In this study the finite element method is utilized to predict the deflection and vibration characteristics of rectangular plates made of saturated porous functionally graded materials (PFGM) within the framework of the third order shear deformation plate theory. Material properties of PFGM plate are supposed to vary continuously along the thickness direction according to the power-law form and the porous plate is assumed of the form where pores are saturated with fluid. Various edge conditions of the plate are analyzed. The governing equations of motion are derived through energy method, using calculus of variations while the finite element model is derived based on the constitutive equation of the porous material. According to the numerical results, it is revealed that the proposed modeling and finite element approach can provide accurate deflection and frequency results of the PFGM plates as compared to the previously published results in literature. The detailed mathematical derivations are presented and numerical investigations are performed while the emphasis is placed on investigating the effect of the several parameters such as porosity volume fraction, material distribution profile, mode number and boundary conditions on the natural frequencies and deflection of the PFGM plates in detail. It is explicitly shown that the deflection and vibration behaviour of porous FGM plates are significantly influenced by these effects. Numerical results are presented to serve as benchmarks for future analyses of FGM plates with porosity phases.

• Journal of Mechanical Science and Technology
• /
• v.19 no.6
• /
• pp.1280-1289
• /
• 2005

This paper presents the effects of corrosion environments of failure pressure model for buried pipelines on failure prediction by using a failure probability. The FORM (first order reliability method) is used in order to estimate the failure probability in the buried pipelines with corrosion defects. The effects of varying distribution types of random variables such as normal, lognormal and Weibull distributions on the failure probability of buried pipelines are systematically investigated. It is found that the failure probability for the MB31G model is larger than that for the B31G model. And the failure probability is estimated as the largest for the Weibull distribution and the smallest for the normal distribution. The effect of data scattering in corrosion environments on failure probability is also investigated and it is recognized that the scattering of wall thickness and yield strength of pipeline affects the failure probability significantly. The normalized margin is defined and estimated. Furthermore, the normalized margin is used to predict the failure probability using the fitting lines between failure probability and normalized margin.

• Journal of architectural history
• /
• v.7 no.3 s.16
• /
• pp.87-105
• /
• 1998

Surveying the literature of architecture since the nineteenth century, one can identify two dominant but problematic attitudes, among several, that pursue the task of defining what modern architecture is and should be. The first is the search for meaning and the second is the pursuit of form. This study, following Michel Foucault, asserts that the dual formation of meaning and form is a historical product of modernity and belies architecture's uncritical dependence on language since the nineteenth century. This study is a critique and historical analysis of this pernicious reliance, and constitutes a first step towards thinking of alternative relations between 'words and architecture' in the modern world. In reconstructing this problematic, the paper has called on Foucault's seminal The Order of Things. The study follows his construction of the Renaissance, the Classical and the Modern episteme, and in brief fashion, reconstructs the relation between language and architecture in each episteme. In analysing the Modern, the study focuses on Hegel's Lectures on Aesthetics. Hegel placed architecture in a genre hierarchy within which architecture, because of its material basis, was fundamentally limited in its ability to express the Spirit. For Hegel it was, among the arts, poetic language, and beyond art, the language of philosophy, through which the Absolute Spirit could be atttained. Much of post-nineteenth century architecture has remained within the shadow of Hegel, where architecture's materiality is perceived to be a burden, and in order to secure its relevance in modern society, architecture was deemed to pursue the role of language. As the most recent and sophisticated example of architecture's pursuit of form, the paper analyses the work of Peter Eisenman. Though Eisenman's theoretical writings are replete with post-Hegelian rhetoric, his architecture remains dependent upon the model of language, albeit a structuralist one. The paper concludes that ultimately, the pursuit of meaning and form is unable to face the crucial issue of value in modernity. While the former decides to easily what it is, the latter evades the issue itself. The second installment of this ongoing study will pursue a third possibility alluded to by Foucault, where language remains silent, pointing only to its 'ponderous' material existence.

• Journal of Fisheries and Marine Sciences Education
• /
• v.28 no.3
• /
• pp.881-892
• /
• 2016

The objective of this research is significant because it derives the core competency factors that members of education communities must have in order to form warm education communities through investigating the perception of special education teachers. To achieve this, 352 special education teachers and teachers working at special education institutes were asked to record three of the most important factors out of a total of 18 factors that members of an educational community considered to be required in order to form warm educational communities. IBM SPSS Statistics 23 was used to analyze the collected data. First, in oder to examine the demographic characteristics of the educators surveyed, frequency analysis was conducted. Second, frequency analysis on the factors that special education teachers considered to be most important to form a warm education communities was conducted by teacher experience and type of education institute they worked for. When analyzing the research results of main factors that special education teachers considered to be important by teacher experience and type of education institute they worked for, responsibility was confirmed to be the most important factor. The second most important factor was communication and the third most important factor was responsibility and trust. In summary, the research confirmed that if mutual trust between the members of an education community can be established and if problems can be solved through cooperation and through open communication, and if each member of the community serves their role responsibly, a warm education community can be formed.

• Journal of Fisheries and Marine Sciences Education
• /
• v.24 no.1
• /
• pp.34-43
• /
• 2012

In order to establish order in fishing industry by cracking down on illegal fishing vessels effectively, it is an essential requirement to identify marking such as the name of fishing vessel and a port of register more easily. Accordingly, it is quite natural that markings on fishing vessels should be marked clearly in an appropriate size on an appropriate site in order for them to be distinguished on the air such as from planes as well as on the sea. Actually, when examining marks such as the name of a vessel which are operating in the country, marks of most fishing vessels are too small as they cannot be distinguished with the naked eye even very closely. There is no coastal fishing vessel which marks the name of fishing vessel on the upper part in order to distinguish it from planes. Fishing vessel law generally which regulates the basic laws about shipbuilding regulates marks on fishing vessel, and fisheries law only regulates sign boards of fishing vessels. Problems and improvement of the marking system on fishing vessels suggested by this paper are as follows. First, in order to contribute to establish order in fishing industry, it would be desirable to tighten standards in fisheries law besides the fishing vessel law. Second, it is difficult to distinguish marks such as the name of a vessel as relevant laws allow fishers to make such marks too small. It is necessary to set the standard for marks larger than those regulated by the international treaty. Third, the relevant laws do not regulate a letter form of marks. Therefore, it becomes a factor to make small marks hard to be distinguished more. It is necessary to decide a clear letter form. Fourth, there is insufficient detailed international standards about the marking system. It is necessary to regulate a detailed standard.

• Journal of Ocean Engineering and Technology
• /
• v.36 no.2
• /
• pp.101-107
• /
• 2022

Dean (1965) proposed the use of the root mean square error (RMSE) in the dynamic free surface boundary condition (DFSBC) and kinematic free-surface boundary condition (KFSBC) as an error evaluation criterion for wave theories. There are well known wave theories with RMSE more than 1%, such as Airy theory, Stokes theory, Dean's stream function theory, Fenton's theory, and trochodial theory for deep-water waves. However, none of them can be applied for deep-water breaking waves. The purpose of this study is to provide a closed-form solution for deep-water waves with RMSE less than 1% even for breaking waves. This study is based on a previous study (Shin, 2016), and all flow fields were simplified for deep-water waves. For a closed-form solution, all Fourier series coefficients and all related parameters are presented with Newton's polynomials, which were determined by curve fitting data (Shin, 2016). For verification, a wave in Miche's limit was calculated, and, the profiles, velocities, and the accelerations were compared with those of 5^th-order Stokes theory. The results give greater velocities and acceleration than 5^th-order Stokes theory, and the wavelength depends on the wave height. The results satisfy the Laplace equation, bottom boundary condition (BBC), and KFSBC, while Stokes theory satisfies only the Laplace equation and BBC. RMSE in DFSBC less than 7.25×10^-2% was obtained. The series order of the proposed method is three, but the series order of 5^th-order Stokes theory is five. Nevertheless, this study provides less RMSE than 5^th-order Stokes theory. As a result, the method is suitable for offshore structural design.

• Journal of Institute of Control, Robotics and Systems
• /
• v.10 no.10
• /
• pp.907-914
• /
• 2004

In this paper, we present a reduced-order observer for a class of nonlinear systems based on the input output linearization. While the most results in the literature presented full-order nonlinear observer, we proposed a procedure for the design of reduced-order observer far nonlinear systems that are not necessarily observable. Assuming that there exists a global observer fer internal dynamics and that certain functions are globally Lipschitz, we can design a global reduced-order observer An illustrative example is included that demonstrate the design procedure of the proposed reduced-order observer.

• Journal of the Chungcheong Mathematical Society
• /
• v.26 no.3
• /
• pp.441-451
• /
• 2013

In this paper, we derive recurrence relations for moments of lower generalized order statistics within a class of doubly truncated distributions. Inverse Weibull, exponentiated Weibull, power function, exponentiated Pareto, exponentiated gamma, generalized exponential, exponentiated log-logistic, generalized inverse Weibull, extended type I generalized logistic, logistic and Gumble distributions are given as illustrative examples. Further, recurrence relations for moments of order statistics and lower record values are obtained as special cases of the lower generalized order statistics, also two theorems for characterizing the general form of distribution based on single moments of lower generalized order statistics are given.