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(An) Empircal Study on the Effects of Knowledge-Strategy Using Balanced Preformance Model
Full text linkThe current world economy has changed from capital based economy to knowledge based economy. It means that company has recognized knowledge as a core. Strategic power for its survival and prosperity and has come to have new management paradigm, so called knowledge management for increasing company competitiveness.
However, it is not easy to measure the outcome of knowledge management since it is invisible.
This study uses the balance performance model of Kaplan and Norton to effectively measure the outcome of knowledge management.
The purpose of the study is to show the importance of knowledge management as a management renovation method for increasing competitive power and improving company values.
This study suggests four performances measurement factors and shows how they influence the competitiveness of a company by an empirical research.
A questionary survey was done to get the research results on a randomly chosen set of large Korea domestic companies which started to knowledge management.
The statistical analysis was done with SPSS 8.0, and the reliability co-efficient total sample was 95.58%.
According to factor analysis, 6 variables were factor 1(management renovation and knowledge ability), 8 variables were factor 2(inner process), 5 variables were factor 3(financial factor), 4 variables were factor 4(customer value).
Using the above 4 factors as independent variables, a multiple regression analysis was done to show how they influenced the four dependent variables of this studythe regression analysis showed that all the four independent variables were positively related to the four dependent variables.
All the 16 hypothesis describing these positive relationships were accepted. Especially the factor 1(management renovation and knowledge ability) was found to be the most dominant factor influencing the dependent variables except the inner environment correspondence ability.
This strongly supports the major assertion of this study that it is not financial factor any more, but knowledge that makes a company competent in today's business environment.Abstract
제1장 서론 = 1
제1절 문제의 제기 = 1
제2절 연구의 목적 = 4
제3절 연구의 방법 = 7
1. 연구대상과 자료수집 = 7
2. 분석방법 = 8
제4절 연구의 범위와 내용 = 9
제2장 지식경영과 균형성과표에 관한 이론적 배경과 선행연구 = 10
제1절 지식경영과 관련된 이론 = 10
1. 지식의 정의와 분류 = 10
2. 지식경영 = 15
제2절 균형성과모형의 특성과 영향요인 = 19
1. 지적자산평가방법 = 20
2. 균형성과모형의 특성과 영향요인 = 22
제3장 연구가설 설정과 변수선정 = 28
제1절 연구모형과 가설설정 = 28
1. 연구모형 = 28
2. 연구가설 = 30
제2절 변수선정과 측정 = 32
1. 독립변수 및 종속변수의 정의와 측정방법 = 33
제4장 균형성과모형을 이용한 지식전략의 영향요인에 관한 실증연구 = 34
제1절 지식전략과 영향요인간의 관련성분석과 결과 = 34
1. 변수의 신뢰성 및 타당성분석 = 34
2. 분석모형과 분석결과 = 39
3. 가설검정 결과 = 46
제5장 결론 = 48
제1절 분석결과의 요약 = 48
제2절 연구의 의의와 한계 = 50
參考文獻 = 53
1. 國內文獻 = 53
2. 國外文獻 = 5
(A) Study on Dynamic and Static Recrystallization Behaviors and Microstructure Evolution Prediction of Die Steels
Full text linkEvaluation of microstructural changes during open die forging of heavy ingots is important for process control. The objective of the control of forging parameters, such as shape of the dies, reduction, temperature and sequence of passes, is to maximize the forging effects and to minimize inhomogeneities of mechanical properties.
A numerical analysis was performed to predict flow curves and dynamic and static recrystallization behaviors of die steel(0.36%C, 1.1%Mn and 1.21%Cr) from hot compression test results. The hot compression tests were carried out in the ranges of temperature 950∼1150℃ and strain rate 0.01∼1.0sec-1. The modeling equation for flow curves was a function of strain, strain rate and temperature. Models for predicting the evolution of microstructure in die steel during thermomechanical processing was developed in terms of dynamic, static recrystallization and grain growth phenomena. The microstructure model was combined with rigid visco-plastic finite element modeling to predict microstructure development. Predicted microstructure is consistent with results obtained in multiple compression tests.
For the grain growth evolution, hot compression test carried out the temperature of 950 and 1150℃, and the strain rate of 0.01 and 1.0sec-1. The specimens were compressed 10%, 20% and 30% in height, unloaded and held for holding times at isothermal condition resulting in static and metadynamic recrystallization in specimens.
The softening occurred during the holding time between the first and the second compression was calculated from the experimental result. Predicted grain size and load are consistent with experiment results from double compression test with constant velocity. Thereforce, the usefulness of the program is verified.Abstract = ⅰ
기호설명 = ⅲ
List of Table and Photographs = ⅳ
List of Figures = ⅵ
1. 서론 = 1
1.1 연구 배경 = 1
1.2 연구 동향 = 2
1.3 연구 목적 = 3
2. 이론적 배경 = 4
2.1 열간 가공시 재료의 미세 조직 변화 = 4
2.1.1 동적 재결정 = 4
2.1.2 정적 및 준동적 재결정 = 6
2.1.3 입자 성장 = 7
2.2 강소성 유한요소법 = 8
3. 실험과 시뮬레이션 = 12
3.1 기초 실험 = 12
3.1.1 동적 재결정 실험 = 12
3.1.2 입자 성장 실험 = 13
3.1.3 정적 및 준동적 연화 실험 = 14
3.2 등속 압축 실험 = 15
3.3 시뮬레이션 = 15
4. 결과 및 고찰 = 18
4.1 유동 곡선 모델링 = 18
4.1.1 구성식 정량화 = 18
4.1.2 유동 응력 곡선 모델링 = 23
4.1.3 재결정 및 입자 성장 모델링 = 27
4.2 기초 실험 결과 및 고찰 = 29
4.2.1 동적 재결정 실험 고찰 = 29
4.2.2 입자 성장 실험 고찰 = 36
4.2.3 정적 및 준동적 연화 실험 고찰 = 41
4.3 시뮬레이션 결과 및 고찰 = 55
5. 결론 = 66
참고문헌 = 6
Study for the Sonar Target Pattern Recognition Based on the Acoustic Scattering Features
Full text linkStudy for the Sonar Target Pattern Recognition
Based on the Acoustic Scattering Features
The objects of active sonar are to detect targets and further to acquire their information such as target specification, dimension, motion and state, after processing their echoes. Especially, classification and discrimination of target using active sonar need to utilize the advanced analysis of target echo features.
Specular reflection and scattering from surface irregularities and inner structures contribute to the target echoes. Since contributors of echoes vary with the target kind and target aspect angle, they consititute basic features of the target signal. Feature parameters of the experimental target signal were extracted in three ways which are the envelope in time domain, the time separation pitch in frequency domain, and the short time Fourier transform in time-frequency domain. The extracted features were applied to the pattern recognition techniques to classify and discriminate target.
Classifying and discriminating similarly shaped targets of which dominant component of the echo is specular reflection result in poor assortment and identification. However, the results show better performance when the effect of inner structures appears in target echoes at the specific aspect angle
(A) Study on the Electrical Characteristics of ZnO Blocks by a Multiple-Lightning Impulse Current
Full text linkThis thesis deals with the changes of the electrical characteristics of ZnO blocks by the application of a single and a multiple-lightning impulse current.
Lightning arresters are the best protective device on electrical power systems against transient overvoltages caused by lightning impulse current and switching operation. Until these days, lightning arresters are estimated only by a single-lightning impulse current in its performance test. However, a multiple-lightning impulse currents are a general feature of natural lightning-ground flashes. It is therefore necessary for lightning arresters to be estimated by applying not only a single-lightning impulse current but also a multiple -lightning impulse current.
In this study, ZnO blocks of 6[㎸], 5[㎄] used in power distribution system have been estimated repeatedly until 200 times by a single and a multiple-lightning impulse current of 8/20[us], 5[㎄].
The multiple-lightning impulse current generator which can produce quadruple 8/20[㎲], 5[㎄] with discrete time between 30∼120[㎳] is designed and fabricated. The total energy applied to the ZnO blocks at each pulse is about 1,200[J].
In experiment, various parameters such as leakage current components, reference voltage, and surface temperature of ZnO blocks are measured with the number of applied impulse current. Also, micro-structure changes of ZnO blocks after applying the single and the multiple-lightning impulse current of 200 times are compared.
From the experimental results, the peak value of the leakage current and the surface temperature of ZnO blocks are increased continuously with the number of applied impulse current, but no significant changes in the RMS value of the leakage current and in the reference voltage are observed.
Also, it is confirmed that the type of ZnO blocks are more vulnerable in deterioration or damage to the multiple-lightning impulse current.목차 = Ⅰ
그림 및 표 목차 = Ⅲ
Abstract = Ⅴ
제 1장 서론 = 1
제 2장 이론 = 8
2.1 ZnO 소자의 구조 및 특성 = 8
2.2 열화 진전 기구 = 15
제 3장 실험장치 및 방법 = 19
3.1 실험장치 및 측정계 = 19
3.2 뇌충격전류 발생장치 = 22
3.3 실험방법 = 29
제 4장 실험결과 및 고찰 = 31
4.1 기본특성 실험 = 31
4.2 뇌충격전류에 의한 가속열화실험 = 33
4.3 광학적 분석 = 40
제 5장 결론 = 43
참고문헌 = 4
(A) Study on Design of RF Module for Spread Spectrum Cordless Telephone
Full text linkDigital communication technology has the various advantages in view of high quality data service, a compacted mobile and base station, and frequency efficiency. The practical advantage of spread spectrum communication is the fact that they can implement various diversity combing using a simple structure.
The ISM band is 902 to 928 MHz. The availability of frequency spectrum in ISM band has spurred the development of a new generation. Wireless products have been appilicated to point of scale terminals, to point-to-point radios in addition to digital cordless telephones.
In this thesis, the spread spectrum digital cordless telephone is implemented. The receiver frequency is 902.3∼905.0M HZ and transmitter frequency is 925.05∼927.75 MHz. In 900 MHz ISM-band, the spread spectrum cordless telephone with QPSK modulation scheme is designed by HP's ADS simulation tool.
The transmitter filter used chebyshev filter with three step and it was constructed of 0.1 dB ripple characteristic. The receiver filter used chebyshev filter with five step and unloaded Q of resonator sets to 1500 in this simulation. From the results of simulation, the processing gain of direct sequence method is shown sufficiently.
The spread spectrum CT is implemented. Characteristics of implemented cordless telephone board is satisfied with designed parameter.Abstract = ⅰ
Nomenclature = ⅱ
제 1 장 서론 = 1
제 2 장 대역확산 통신 및 ISM 대역 = 3
제 2-1 절 대역확산 = 3
제 2-2 절 QPSK 변복조 방식 = 6
제 2-3 절 ISM 밴드 = 10
제 3 장 RF 모듈 설계 및 구현 = 12
제 3-1 절 송신부 설계 = 13
제 3-2 절 수신단 설계 = 24
제 3-3 절 RF 부품 반도체 소자특성 = 33
제 4 장 결론 = 35
참고문헌 = 3
Development of a Magnetic Fluid Linear Pump for Medical Purpose
Full text linkMagnetic fluid is liquid, so it moves under the external forces. It is also rigid under the magnetic field enough to maintain against the external forces. This very special characteristic can be applied to the various types of actuators or sensors. In this thesis, the linear pump by using magnetic fluid was developed for medical purpose. the advantages of the MFLP (magnetic fluid linear pump) is that it could pump the non-conductive, non-magnetic liquid such as insulin or blood because of the segregation structure of the magnetic fluid and pumping liquid by thin rubber. The sequential currents are needed to produce pumping forces. The excessive forces at pumping moment could cause the medical shock, and weak forces at intermediate moment could cause the back flow of the pumping liquid. So, the ripples of the pumping forces need to be controlled for the medical application. In this device, the pumping force and pumping speed could be controlled by current scheme.
In this thesis, the method to compute the pumping forces of the MFLP is derived. The change of magnetic fluid surface according to the driving currents could be obtained by magneto-hydrodynamic analysis so that pumping forces could be computed by integration of the surface moving to the pumping direction at each moment. Optimum design using 3-D finite element method with hydrodynamic analysis was performed. The actual MFLP with 12mm diameter was made and tested for experiments. The effects of driving current and frequency on the pumping forces and pumping speed were analyzed and compared with experimental measurements.목차
Abstract
제1장 서론 = 1
1.1 연구배경 및 목적 = 1
1.2 연구개요 = 3
제2장 자성유체의 구조와 성질 = 5
2.1 자성유체의 물성 = 5
2.2 자성유체의 성질 = 6
2.3 자성유체의 응용 = 7
제3장 자성유체의 해석 = 9
3.1 선형운동량 해석 = 9
3.2 Navier-Stokes방정식에 의한 유체해석 = 17
3.3 유한요소법에 의한 자기장 해석 = 21
3.4 유체의 형태를 결정하는 수치해석 = 24
？？4장 MFLP의 구조 및 설계 = 31
4.1 MFLP의 구조 = 31
4.2 MFLP의 원리 = 33
4.3 MFLP 최적 설계 = 37
제5장 MFLP 제작 = 41
제6장 MFLP 실험 및 운전 = 47
6.1 MFLP의 관내 자기장 분포 = 47
6.2 MFLP 관내 자성유체의 형상 = 52
6.3 MFLP 운전 = 55
6.4 선형 펌프의 펌핑 속도와 펌핑 압력 = 59
제7장 결론 = 62
참고문헌 = 6
Neural Networks and Molecular Analyses of Circulating Piggery Slurry Treatment System
Full text link유기물질과 질소·인 등의 영양물질이 고농도로 포함된 축산폐수는 수계의 주요 오염 물질 중 하나다. 본 연구에서는 혐기성 및 호기성 조건에서 연속식으로 돈분폐수를 처리하고 처리된 방류수의 일부를 축사에 재이용 할 수 있는 순환식 돈분폐수 처리 시스템의 처리기작에 관한 연구를 수행하였다. 이 시스템은 축사나 처리조에서 발생되는 악취와 BOD를 포함한 기타 오염물질을 효과적으로 제거할 수 있으며, 돼지 1000두 이하의 소규모 농가에 적합한 처리공정 중 하나로 알려져 있다. 시스템내에서 우점종으로 분리된 타가영양박테리아는 호기성 및 혐기성 조건에서 질산화 및 탈질작용에 관여하는 것으로 밝혀진 Alcaligenes faecalis (TSA-3)와 Brevundimonas diminuta (TSA-1), 그리고 Abiotrophia defectiva (TSA-2)가 분리되었고, 혐기성 조에서는 유산균 박테리아 MRS-1 (미동정) 외 2종(Streptococcus sp. : MRS-3)이 분리되었다. 그 중 최우점종은 Alcaligenes faecalis (TSA-3)로 나타났다.
중합효소 연쇄반응(polymerase chain reactionPCR) 등의 분자생물？隙？ 기법을 이용하여 시스템으로부터 분리된 타가영양박테리아에 의한 암모니아성 질소 제거 기작을 밝혔다. 여기서 암모니아 흡수 및 이용에 관여하는 글루타민 합성효소(glutamine synthetase: GS)유전자의 존재를 확인하였다.
또한 신경회로망을 이용하여 순환식 돈분처리 시스템의 실시간 모니터링을 궁극적으로 구현할 수 있는 새로운 방법을 제안하였다. 즉 미생물 군집내의 개체군밀도에 따른 각 처리조(유입수, 발효조, 폭기조, 1차 침전조 및 4차 침전조)에서의 폐수처리 기작에 대한 모델을 시도하였다. 측정 데이터에 대해 우선 주요 요소 해석(principal component analysis: PCA) 방법을 적용하여 각 처리조에서의 입력(미생물 밀도와 처리요소)과 출력간의 상관관계를 파악하고, 각각의 처리조마다 독립된 신경회로망을 적용하여 폐수처리 과정을 모델링하였다. 신경회로망의 입력으로 현재 탱크에서의 미생물의 개체군밀도를 직접 이용하는 대신 PCA 분석 결과를 이용함으로써, 비교적 적은 수의 데이터로 효과적인 모니터링 시스템을 구현할 수 있었다. 즉, 각 처리조별로 학습된 신경회로망들을 연결하여 분석한 결과 2일 동안의 폐수 처리 변화를 비교적 정확히 예측할 수 있었다.TABLE OF CONTENTS =ⅰ
LIST OF TABLES = ⅲ
LIST OF FIGURES =ⅳ
ABSTRACT = ⅵ
Ⅰ. INTRODUCTION = 1
Ⅱ. LITERATURE REVIEW = 4
2.1 Swine Wastewater Pollution and Treatment Technology = 4
2.1.1 Pollution Status and Characteristics of Swine Wastewater = 4
2.1.2 Treatment Technologies of Swine Wastewater = 6
2.2 Modeling Using Neural Networks = 6
2.2.1 Characteristics of Neural Networks and Principal Component Analysis = 6
2.3 Mechanisms of Biologycal Nitrogen and Phosphorus Removal = 12
Ⅲ. Materials and Methods = 15
3.1 System Overview = 15
3.2 Isolation, Identification and Quantification of Microorganisms = 17
3.3 Analytical Methods for Piggery Slurry samples from the Treatment System = 18
3.4 Modeling of the Treatment System Using Neural Networks = 18
3.5 Ammonium Uptake and Utilization Test = 21
3.6 Extraction of Total DNA = 21
3.7 PCR Amplification of Glutamine synthetase Gene and Southern Blot Hybridization = 22
Ⅳ. Results and Discussion =24
4.1 Microbial Identification, and Analyses of the Population Dynamics and Piggery Slurry Treatment = 24
4.2 Wastewater Treatment Efficiency of the Treatment System = 31
4.3 Principal Component Analysis of Input Data = 38
4.4 Modeling of Treatment System by Neural Networks = 42
4.5 Molecular Analysis of Ammonium Removal = 43
Ⅴ. Conclusion = 46
FUTURE TASKS
REFERENCES
ACKNOWLEDGEMENT
CURRICULUM VITA
(A) Study on a Design & Implementation of Internet Broadcasting System
Full text linkThis paper presents the design and implementation of University Internet Broadcasting system for moving picture realtime broadcasting and VOD broadcasting service.
In order to achieve these purpose, program planning, construction procedure, realtime broadcasting transfer module and VOD broadcasting module are described.
This paper is describe by following order. First, we studied on preference of use by internet user for broadcasting name, program plans bearing and plans strategy. Second, we implement broadcasting system for internet transfer.
Third, homepage of broadcasting station is simple for providing a user with convenience. Fourth, we compose best effort of audio and video encoding, transmission speed for providing a user with good program.
For the condition gratification of this paper, we constructed and transmitted speciality education program for distinction between University Internet Broadcasting and other internet broadcasting of contents.
This paper is composed of 5 chapters. Chapter 1 describes the historical background and goals of this work, outline of remaining chapter. Chapter 2 describes the internet broadcasting of concept and general purpose of use by internet user. Chapter 3 describes the design and implement of University Internet Broadcasting station and each modules of it. There describes the program planning and construction. Chapter 4 describes the design result of contents and program planning. Chapter 5 summarizes all results obtained in chapter 2, 3, 4 and includes the further research topics and the work to be supplemented.Abstract
제 1 장 서론 = 1
1.1 연구의 배경 및 목적 = 1
1.2 연구의 내용 = 2
제 2 장 인터넷방송의 배경 및 특성 = 4
2.1 인터넷방송의 개념 = 4
2.2 인터넷방송의 현황 및 종류 = 8
2.3 인터넷방송국의 동향분석 = 10
제 3 장 대학인터넷방송국의 시스템 설계 및 구축 = 13
3.1 대학인터넷방송국 개국 절차 = 13
3.2 대학인터넷방송국의 운영요건 = 16
3.3 대학인터넷방송국의 시스템 설계 = 22
3.4 시스템 구축 = 38
3.5 컨텐츠 제작 = 39
제 4 장 실시간 및 VOD 방송 모듈 구현 = 43
4.1 서버 측에서 방송 모듈의 송출제어 = 43
4.2 클라이언트 측에서 실시간 방송 모듈의 요청 = 51
4.3 클라이언트 측에서 VOD 방송 모듈의 요청 = 53
제 5 장 결론 = 56
참고문
A Study on Implementation of TCP/IP based Remote Control System using Embedded Linux
Full text linkEmbedded system is defined as the device of executing limited and special function and composed of embedded type on system. Recently, embedded systems are interconnected by means of network. Connecting type of embedded system forms network group into embedded system collection of one division. And, it's layer construction consists of upper network group which is gathered these groups.
Embedded OS is porting operating system in special purpose hardware. In the first stage, system was simple, therefore operating system wasn't needed. But recently system has been complex, and operating system concept appears to be important.
Embedded system must be satisfied with condition of ethernet port, serial and parallel port, small size, low cost. Best operating system of satisfying it in this condition is Linux.
This thesis is focused on network connecting technique of using embedded Linux and implementing remote control system base function using TCP/IP with manufactured target board. Analyzing embedded Linux kernel consisting of process management, file system, network management, device management, and we set up data for the development.
In this study, it implements remote control system base function using TCP/IP and StrongARM processor of INTEL INC. But, it suggested potentiality of system implementation using other processor embedded in Linux porting technique and establishment of control system design.
As this system develops, we can transmit remote data in embedded network environment of efficient and trustable. We consider embedded OS can be easily embedded in 16 bit and 32 bit processor.목차
Abstract
제1장 서론 = 1
1.1 연구의 배경 = 1
1.2 연구의 목적 및 내용 = 2
제2장 임베디드 네트워크 = 4
2.1 임베디드 네트워크 환경 = 4
2.2 임베디드 리눅스 커널의 개요 = 5
2.3 임베디드 리눅스 부팅 코드 분석 및 부팅과정 = 23
제3장 원격 제어시스템의 설계 및 구현 = 26
3.1 시스템의 개요 = 26
3.2 임베디드 시스템 포팅을 위한 환경 구성 = 29
3.3 SA-1110의 분석 및 회로의 구성 = 36
3.4 시험회로의 평가 = 43
제4장 결론 = 50
참고문헌 = 52
부록 : 타겟 보드 시스템 회로도 = 5
The Effect of Vehicle Driving Modes on Fuel Consumption
Full text linkThe era of high-priced oil has opened its stage as they went through oil crises twice in 1970s. Although the oil price has been stabilized since 1980s consecutive exchange rate increase and rapid increase of the oil price have increased the burden on the consumers who use oil energies.
Also, the increase of vehicles are becoming the major factors for the global environment contamination, and the exhaust regulations restricted to hydrocarbon, nitrogen oxide, carbon monoxide are expanded to cover carbon dioxide, as related to the recent day-to-day global warming. As the amount of CO₂ increases as the fossil fuels used for the vehicles are combusted ideally, the ways of reducing the CO₂ itself using combustion technology or post-processing technology are not being presented. The only way is to reduce the use of fuels, and for this reason many researches are in progress.
Vehicles are used by many drivers who have different driving habits, and the driving modes are also different accordingly.
Selecting the driving mode properly and driving in efficient areas can reduce the fuel consumption dramatically. Also, vehicles consume the height energy and the motion energy with the braking energy when they go down a hill or when they brake. They have Fuel cut-off capability in order to recall this energy, and the driving utilizing this can further save the fuel.
This paper intends to make a calculating program that can calculate the fuel consumption rate in the general driving mode, and using this compare the fuel consumption rates for the fast accelerating mode, the normal mode and the slow accelerating mode, and after the collective examination will present the best driving mode when driving on flat lands.
As the result, We would be predict the best running mode and save 24% fuel oil as well.목차
Abstract = III
Nomenclature = V
제 1 장 서론 = 1
제 2 장 수학적 모델 및 해석 알고리즘 = 3
2.1 차량 주행 저항과 엔진 토크 = 3
2.2 연료 공급의 제어특성 = 6
2.3 해석 알고리즘 = 9
제 3 장 계산 조건 = 13
3.1 적용 차량의 사양 = 13
3.2 적용 모드의 종류 = 16
제 4 장 계산 결과 및 고찰 = 18
4.1 계산 결과 = 18
4.1.1 급 가속 운전모드(Fast running mode) = 18
4.1.2 보통 운전 모드-1(Nomal running mode-1) = 23
4.1.3 보통 운전 모드-2(Nomal running mode-2)= 28
4.1.4 저 가속 운전 모드 = 32
4.2 고찰 = 36
제 5 장 결론 = 48
參考文獻 = 5