• Journal of Mechanical Science and Technology
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• v.14 no.10
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• pp.1061-1071
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• 2000

Linear cyclic systems (LCS's) are a class of systems whose dynamic behavior changes periodically. Such a cyclic behavior is ubiquitous in systems with fundamentally repetitive motion. Yet, the knowledge of the noise and vibration transmission paths in LCS's is quite limited due to the time-varying nature of their dynamics. The first part of this two-part paper derives a generic expression that describes how the noise and/or vibration are transmitted between two (or multiple) points in the LCS's. In Part II, experimental validation of the theoretical development of Part I is provided. The noise and vibration transmission paths of the scroll and rotary compressors (two typical LCS's) are examined to show that the LCS's indeed generate a series of amplitude modulated input signals at the output, where the carrier frequencies are harmonic multiples of the LCS' fundamental frequency. The criterion proposed in Part I to determine how well a given LCS can be approximated as a linear time-invariant systems (LTIS) is applied to the noise and vibration transmission paths of the two compressors. Furthermore, the implications of the experimental validations/applications are discussed in order to assess the applicability of the noise/vibration source and transmission path identification techniques based on the assumption that the system under consideration is linear and time-invariant.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.374-377
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• 2012

GNSS(Global Navigation Satellite System) based land transportation infrastructure system is consists of receiving station and central station. The functions of the central system include receiving station's data gathering and decoding, carrier correction and integrity information generated, transmission of data in real-time. In general, The central station architecture should take into account various important points relating to hardware/software of system, data archiving and checking, availability and continuity of operation, etc. There is a fundamental need for a generic design capable of being used in any situation. Also, There is need to develop an expandable and interoperable central station architecture. In this paper, the process of design and manufacture and verification will be introduced.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.2
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• pp.370-378
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• 2007

${\ulcorner}$Zhujieshanghanlun(註解傷寒論)${\lrcorner}$ are som particular points as below ; first, set up the concepts of chuanjing(傅經), zaichuanjing(再傅經), and guojing(過經). Second, suggested the half exterior and half interior syndrome(半表半裏證) firstly. The third, understood origin literature by the distinguished way for syndrome in accordance with the Yin and Yang(陰陽). Forth, wangyang(亡陽) is described by two different syndromes. One is with perspiration. The other is yangxuzheng(양허증(陽虛證)) from injured yangqi(陽氣). Fifth, xialibiannongxue(下利便膿血) was distinguished by the generic characters of The Cold and Hot(熱${\cdot}$寒). The last, ${\ulcorner}$Shanghanlun${\lrcorner}$ (傷寒論) was described at the view of viscera & bowels's physiology and their pathology. And shaoyin(少陰) disease was aware of kidney case and Taiyin(太陰) disease was aware of spleen case. There are two different cases of bowel diseases. One is that xieqi(邪氣) goes in stomach of Yangming(陽明). The other is that xieqi(邪氣) follows channel and goes into bowel.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.4
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• pp.58-65
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• 2005

A method measuring angular speed and estimating angular acceleration of an automotive wind shield wiper pivot with limited resources has been proposed. Limited resources refer to the fact that processes cannot be operated in real-time with a regular notebook running a Microsoft Windows. Also, they refer to the fact that data acquisition cards have only two general purpose counters as many generic cards do. An optical incremental encoder has been employed for measuring angular motion. To measure the angular speed of the pivot, periods for the encoder's output pulses have been measured as the speed is related to the reciprocal of the period. Since only information acquired from one counter channel is the magnitude of the angular speed, sign correction is necessary. Also the information for the exact time when a pivot passes left and right dead points is also missing and the situation is inherent to the hardware setup. To find out the zero-crossing time of the angular speed, a linear interpolation technique has been employed. Lastly, to overcome the imperfection of the mechanical encoders, the angular speed has been curve fitted to a spline. Angular acceleration can be obtained by a differentiation of the angular speed.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2699-2701
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• 2001

The study is concerned with an approach to the design of a new category of fuzzy neural networks. The proposed Fuzzy Polynomial Neural Networks(FPNN) with hybrid multi-layer inference architecture is based on fuzzy neural networks(FNN) and polynomial neural networks(PNN) for model identification of complex and nonlinear systems. The one and the other are considered as premise and consequence part of FPNN respectively. We introduce two kinds of FPNN architectures, namely the generic and advanced types depending on the connection points (nodes) of the layer of FNN. Owing to the specific features of two combined architectures, it is possible to consider the nonlinear characteristics of process and to get output performance with superb predictive ability. The availability and feasibility of the FPNN is discussed and illustrated with the aid of two representative numerical examples. The results show that the proposed FPNN can produce the model with higher accuracy and predictive ability than any other method presented previously.

• Explosives and Blasting
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• v.39 no.3
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• pp.44-64
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• 2021

With the upcoming 4^th industrial revolution era, the applications of artificial intelligence(AI) and big data in engineering are increasing. In the field of blasting, there have been various reported cases of the application of AI. In this paper, AI techniques, such as artificial neural network, fuzzy logic, generic algorithm, swarm intelligence, and support vector machine, which are widely applied in blasting area, are introduced, The studies about the application of AI for the prediction of ground vibration, rock fragmentation, fly rock, air overpressure, and back break are surveyed and summarized. It is for providing starting points for the discussion of active application of AI on effective and safe blasting design, enhancing blasting performance, and minimizing the environmental impact due to blasting.

• Korea Trade Review
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• v.44 no.4
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• pp.205-220
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• 2019

This article recapitulates the recent changes in trade laws, which may be accentuated due to the intriguing emergence of fortified protectionism and Mega FTAs. It points out the need to formulate not only the corporate strategy for enhancing the product differentiation and architectural capabilities but also the public policy, which comprises the industrial adjustment policy to cope with possible negative impulses caused by the digital trade and foreign direct investment. It is imperative for Korea to facilitate the alignment between corporate strategy and industrial adjustment policy as an effective means of enhancing industrial structure by nurturing those linkage effects between relevant forward and backward industries. Given the drastically volatile trade norms of multi-track trade policies, it may be a pivotal momentum for Korea to pursue a paradigm shift of its trade policy with a prime objective of achieving such an alignment between corporate strategy and industrial adjustment policy, which affords increased value-added and the further development of product or generic technology instead of resorting to the misuses and abuses of economies of scale and production technology for the maximization of export amount.

• The Korean Journal of Applied Statistics
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• v.23 no.1
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• pp.139-150
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• 2010

In recent years, more generic drug products became available. The current regulation for assessing the bioequivalence of two drug formulations is based on the concept of average bioequivalence. This approach has been indicated to be insufficient for assessing switchability between two drug formulations and US FDA has adopted individual bioequivalence as one of the bioequivalence criterion since 2001. The US FDA recommends that individual bioequivalence be assessed based on $2\;{\times}\;4$ crossover design, while a $2\;{\times}\;3$ crossover design may be used as an alternative design to reduce the length and cost of the study. In this paper, a statistical procedure for assessment of individual bioequivalence under $3\;{\times}\;2$ crossover designs is proposed and some statistical points are discussed with $2\;{\times}\;3$ crossover design and $2\;{\times}\;3$ extra-reference design through simulation studies.

• Journal of the Korean Dietetic Association
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• v.7 no.1
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• pp.56-64
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• 2001

The study was conducted to assess sanitary concepts of employees and needs of HACCP-based sanitation training program for elementary school foodservice operations. Subjects consisted of 370 foodservice employees. Foodservice employees' demographic characteristics were surveyed, and their food sanitation knowledge was tested. Food sanitation knowledge included 4 dimensions of foodborne disease & food microbiology; sanitary management in food product flows; personal hygiene management; and equipment & facility sanitation management. The data were analysed using the SPSS package for descriptive analysis, t-test and ANOVA test. The average sanitation knowledge score was 9.5 out of 15. The working periods of foodservice employees were singnificantly(p<01) related to food sanitation knowledge dimensions. Correct answering rate of 4 sanitation management dimensions were 74.4% in foodborne disease & food microbiology; 536% in sanitary management in food product flows; 78.7% in personal hygiene management; and 50.5% in equipment & facility sanitation management. 6 items in 4 sanitation knowledge dimensions under mean score were identified. Those items were temperature danger zone, thawing method of frozen foods, cooking & holding temperature, proper sampling & storage methods, proper storing methods in refrigerator, and proper washing & sanitizing method for utensils. Identified 6 items were included in 12 critical control points developed for the elementary school generic HACCP plan, and should be emphasized in implementing HACCP-based sanitation training program.

• International Journal of Automotive Technology
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• v.8 no.6
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• pp.731-744
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• 2007

A method for dynamic analysis and design calculation of a Powertrain Mounting System(PMS) including Hydraulic Engine Mounts(HEM) is developed with the aim of controlling powertrain motion and reducing low-frequency vibration in pitch and bounce modes. Here the pitch mode of the powertrain is defined as the mode rotating around the crankshaft of an engine for a transversely mounted powertrain. The powertrain is modeled as a rigid body connected to rigid ground by rubber mounts and/or HEMs. A mount is simplified as a three-dimensional spring with damping elements in its Local Coordinate System(LCS). The relation between force and displacement of each mount in its LCS is usually nonlinear and is simplified as piecewise linear in five ranges in this paper. An equation for estimating displacements of the powertrain center of gravity(C.G.) under static or quasi-static load is developed using Newton's second law, and an iterative algorithm is presented to calculate the displacements. Also an equation for analyzing the dynamic response of the powertrain under ground and engine shake excitations is derived using Newton's second law. Formulae for calculating reaction forces and displacements at each mount are presented. A generic PMS with four rubber mounts or two rubber mounts and two HEMs are used to validate the dynamic analysis and design calculation methods. Calculated displacements of the powertrain C.G. under static or quasi-static loads show that a powertrain motion can meet the displacement limits by properly selecting the stiffness and coordinates of the tuning points of each mount in its LCS using the calculation methods developed in this paper. Simulation results of the dynamic responses of a powertrain C.G. and the reaction forces at mounts demonstrate that resonance peaks can be reduced effectively with HEMs designed on the basis of the proposed methods.