뇌파 선행 실험연구 분석에 의한 색채반응에 관한 연구

신동준(Shin, DongJun),김주연(Kim, JooYun) 한국색채학회 2017 한국색채학회 논문집 Vol.31 No.4

Frequency Response Characteristics of Air-Cooled Condenser in Case of Inputting Various Disturbances

Kim, Jae-Dol,Oh, Hoo-Kyu,Yoon, Jung-In The Society of Air-Conditioning and Refrigerating 2000 International Journal Of Air-Conditioning and Refr Vol.8 No.1

The frequency response characteristics of a condenser were numerically studied for the control of refrigeration and air conditioning systems. The important parameters, such as the refrigerant flow rate, refrigerant temperature, air velocity, and air temperature at the condenser inlet, were analyzed. Superheated vapor, two phase, and subcooled liquid domain in condenser can be described by using the energy balance equation and the mass balance equation in refrigerant and tube wall, the basic equation for describing the dynamic characteristics of condenser can be derived. The transfer function for describing dynamic response of the condenser to disturbances can be obtained from using linearizations and Laplace transformations of the equation. From this transfer function, analytical investigation which affects the frequency responses of condenser has been made. Block diagrams were made based on the analytic transfer function; dynamic responses were evaluated in Bode diagrams on the frequency response. Through this study, it became possible that the information about the dynamic characteristics of air-cooled condenser is offered. The results may be used for determining the optimum design parameters in actual components and entire systems. Also, the mathematical models, frequency response may be used to help understanding, evaluate optimum design parameters, design control systems and determine on setting the best controller for the refrigeration and air-conditioning systems.

한국인의 사회심리 특성이 SNS 감정반응에 미치는 영향

염동섭 한국비즈니스학회 2024 비즈니스융복합연구 Vol.9 No.3

소셜 미디어의 보급과 확산으로 국내 SNS 이용률은 세대를 불문하고 꾸준히 증가하고 있는 추세이다. 그러나 관련 연구에 있어 이용자들의 사회심리 특성을 반영한 연구는 찾아보기 어려운 실정이다. 이에 본 연구는 이용자들의 사회심리 특성 변인을 기반으로 연구를 진행하고자 하였다. 구체적으로 한국인의 사회심리 특성(체면, 우쭐, 눈치)이 SNS 감정반응에 미치는 영향을 살펴보기 위한 목적에서 진행되었다. 이를 위해 남, 여 대학생을 대상으로 자기기입식 설문조사 방법으로 자료를 수집하였으며, 총 171명의 데이터가 분석에 이용되었다. 연구결과 첫째, 체면 특성과 눈치 특성이 이용자들의 긍정적 감정반응에 정(+)의 영향을 미치는 것으로 나타났다. 즉, 체면 특성과 눈치 특성이 높을수록 긍정적 감정반응이 높아지는 것으로 나타났다. 둘째, 체면 특성만 이용자들의 부정적 감정반응에 정(+)의 영향을 미치는 것으로 나타났다. 즉, 체면 특성이 높을수록 부정적 감정반응도 높아지는 것으로 나타났다. 결론적으로 한국인의 사회심리 특성 중 SNS를 이용하는 데 있어 나타나는 감정반응에 미치는 상대적 영향력의 정도는 체면 특성이 매우 중요하게 작용하는 것으로 나타났다. 이러한 결과는 SNS 관련 연구에 있어 한국인의 사회심리 특성을 반영했다는 측면에서 차별점이 있으며, 본 연구를 통해 관련 연구 영역을 확장했다는 학문적 의의를 제공한다. With the proliferation of social media, its use is steadily increasing across generations in South Korea. However, it is difficult to find social media-related research that addresses the socio-psychological characteristics of its users. This study was focused on the socio-psychological characteristic variables of social media users. Specifically, the study aimed to examine the effect of three socio-psychological characteristics of Koreans (Chemyon, Uzzul and Nunchi) on their emotional responses in social media. To this end, data were collected through a self-administered survey targeting male and female college students, with data from a total of 171 students used in the analysis. The findings are as follows. First, it was found that the characteristics of chemyon and nunchi have a positive (+) effect on social media users’ positive emotional responses. In other words, the more a user chemyon and nunchi, the higher their positive emotional response. Second, of the three characteristics, only chemyon was also found to have a positive (+) effect on a user’s negative emotional responses. In other words, the more the user tried to chemyon, the higher their negative emotional responses. In conclusion, the relative influence of chemyon characteristics on emotional responses to SNS use was found to be very important among the socio-psychological characteristics of Koreans. This study differs from other studies in that it addresses the socio-psychological characteristics of Koreans in social media-related research. It also has academic significance in expanding the related research field.

Effects of Foundation Soil Stiffness on the 3-D Modal Characteristics and Seismic Response of a Highway Bridge

Mouloud Ouanani,Boualem Tiliouine 대한토목학회 2015 KSCE JOURNAL OF CIVIL ENGINEERING Vol.19 No.4

This paper presents the main results of an investigation into the influence of foundation soil stiffness on the modal characteristics and seismic response of a highway bridge with spread foundations. A sensitivity study including six types of soil profiles is first performed to examine the effects of foundation soil stiffness on critical dynamic response parameters of the bridge. 3-D modal characteristics of lateral, vertical, longitudinal and torsional vibrations modes are identified and compared for various soil and rock conditions. The study is then extended to estimate the time history nonlinear seismic response of coupled foundation soil-bridge models utilizing an extension of the Fast Nonlinear Analysis (FNA) algorithm. Two different approaches for modeling soil foundation interaction are considered: a PGA consistent linear soil model and an advanced non linear soil model. Results show, among others, the major influence of soil flexibility effects on the modal characteristics and seismic response behavior of the bridge. Moreover, the results illustrate clearly the importance of soil nonlinearity on coupled foundation soil-bridge response. It follows, from a design perspective, that analytical models used for the seismic analysis of bridge structures should explicitly consider the effects of soil-structure interaction including nonlinear soil behavior.

공기호흡기용 무선통신 시스템의 공간 특성에 따른 응답시간에 관한 연구

김민욱(Min-Wook Kim),이건호(Gun-Ho Lee),박용환(Yong-Hwan Park) 한국화재소방학회 2021 한국화재소방학회논문지 Vol.35 No.1

이미 선진국에서는 다양한 지역 특성 요인을 반영하여 세계적 규모의 훈련장을 설치하여 실무 위주의 교육 훈련을 시행하고, 종합적 국토안보 운용방안을 제시하고 있다. 국내의 중앙소방학교를 비롯한 각 지역 소방학교에서도다양한 훈련장을 구비하여, 대원들이 교육 및 훈련을 받고 있지만, 대원들이 사용하는 공기호흡기의 정보를 기록,저장하거나 호흡기의 잔량을 지휘소에서 여러 정보를 확인하며, 진행하는 경우는 전무한 실정이다. 본 연구에서는공기호흡기 사용자 정보를 무선으로 수신기에 제공하는 공기호흡기 무선통신시스템을 개발하여 공간 특성에 따른거리별 응답시간 측정실험을 진행하였다. 실험결과 실내 개방된 공간에서는 평균적으로 약 5.09 s 이내에 응답하였고, 샌드위치 패널 1장으로 막힌 공간에서는 약 5.19 s, 샌드위치 패널 2장으로 막힌 공간에서는 약 5.79 s로 샌드위치패널이 100 mm 이상이 되는 경우 응답속도에 영향을 주는 것으로 분석되었다. In developed countries, global-scale training centers are installed to reflect various regional factors, provide practicaleducation and training, and present comprehensive homeland security management plans. Each local firefighting school,including the central firefighting school in Korea, has various training grounds where firefighters receive education andtraining. However, the recording and storing of information regarding the air respirator used by the crew during this trainingis not maintained, nor is information on the remaining air respiratory system at the command post checked. In this study,we developed a wireless communication system for respirators that provides user information and conducted an experimentto measure response time by distance according to spatial characteristics. As a result of the experiment, the response wasapproximately 5.09 s on average in open space, approximately 5.19 s in the location blocked by one sandwich panel, andapproximately 5.79 s in the location blocked by two sandwich panels. Therefore, it was determined that the response speedwas affected when the sandwich panel was 100 mm or more.

A Study on Indicial Response Characteristics of a Gas-Lubricated Spiral-Grooved Journal Bearing

H. YABE,T. KANESHIRO,T. HIRAYAMA 한국트라이볼로지학회 2002 한국트라이볼로지학회 학술대회 Vol.2002 No.10

Indicial response characteristics of a rotor supported by a gas-lubricated, spiral-grooved journal bearing are studied theoretically to develop a fundamental investigation for the bearing design with considering NRRO characteristics. The trajectory of rotor movement is calculated by applying the non-linear orbit scheme against a prescribed impulse load, then two characteristic quantities are introduced to evaluate the indicial response performance of the bearing, i.e., "maximum deviation of rotor center" and "integrated rotor center deviation". The effects of some design parameters of spiral grooves to these representative quantities are studied so that "robust" design against impulse load is discussed.

대전입자형 디스플레이의 균등전계내 대전입자의 거동특성에 관한 연구

이동진,김영조,Lee, Dong-Jin,Kim, Young-Cho 한국산학기술학회 2009 한국산학기술학회논문지 Vol.10 No.6

본 논문에서는 균일한 전계내의 대전입자의 운동특성에 대하여 연구하였다. 패널을 제작하기 위하여 양전하를 띠는 검은색 대전입자(토너)와 음전하를 띠는 노란색 대전입자(토너)를 사용하였으며, 패널구동을 위하여 오버슈트 현상이 없는 power supply로 구형펄스를 인가하였다. 또한 RT-200을 이용하여 광학특성(대조비, 시야각)을 측정하였으며, 레이저와 포토다이오드를 사용하여 응답속도를 측정하였다. 그리고 응답속도와 대조비를 통하여 대전입자의 m/q 분포를 확인하였다. 그 결과, 대전입자의 구동전압, 대조비, 응답속도는 m/g에 의해 결정되며, 패널내부에 주입된 대전입자의 m/q 분포가 동일할수록 구동특성이 향상되었다. In this paper, we studied on a characteristic of movement of charged particle in equal electric field. In order to fabricate a panel, we used positive charged toner particles of black and negative one of yellow. Panel was biased rectangle pulse without any overshoot. Also, panel's optical characteristics with contrast ratio and viewing angle is measured with RT-200. Response time was measure by using incident laser and detective photodiode. The distribution of m/q of particles by driving in panel throughout the contrast ratio and response time. As a results, driving voltage, contrast ratio, and response time are decided by m/q of charged particles and when m/q of charged particles in panel have regular distribution, it is induce improvement driving characteristics.

Investigation on large turbo-generator stator end winding dynamic characteristics based on response surface method

Zhao, Yang,Xiao, Yang,Lu, Sheng,Sun, Hao,Huo, Wenhao,Liao, Yong The Korean Institute of Power Electronics 2021 JOURNAL OF POWER ELECTRONICS Vol.21 No.10

The natural frequencies corresponding to the particular mode shapes of a large turbo-generator must not be in the resonance region before delivery. Different parameters may clearly affect these dynamic characteristics. Different from other studies, this paper introduces a method for obtaining the inherent characteristics of end winding in a short period of time under multiple simultaneously changing parameters. The proposed process is based on the response surface method (RSM). In this method, the main concerned natural frequencies were taken as the critical index to describe the dynamic behaviors of the end winding, with which the mathematical relationship between the dynamic characteristics and design variables was analyzed. First, the stiffness of the rings, stiffness of the radial braces and number of pins bonded to the radial braces were used as samples for orthogonal experimental design. Then, the natural modes and frequencies of 25 different samples were acquired by conducting modal analysis with ABAQUS software. Utilizing these dynamic results, a second-order polynomial response surface model was established to describe the relationships between natural frequencies and these three different parameters. Then, the quality of this model was verified by calculating the valuating indexes for comparison with support vector regression (SVR). With the response surface model, the variation regularities of the natural frequencies and modes due to the above parameters were discussed. The method proposed in this paper can enable natural frequencies in the whole design space to be quickly determined without finite-element analysis, greatly improving the development efficiency and laying a foundation for dynamic response prediction during normal operation with different parameters and additional large turbo-generator stator end winding optimization.

Wave Response Analysis for Pontoon-type Pier: Very Large Floating Structure

Sang-Do Lee,Sung-Hyeon Park,Gil-Young Kong 해양환경안전학회 2016 海洋環境安全學會誌 Vol.22 No.1

본 연구에서는 국내 여수항만에 길이 500미터, 폭 200미터, 두께 2미터인 폰툰형 VLFS타입의 해상부두를 제안하였다. 이 구조물은 해상에서 오랫동안 파랑하중을 견뎌야하므로 파랑응답해석이 필수적이다. 유체-구조부 해석에는 직접법을 사용하였고, 연성운동방정식을 수치해석하여 응답 결과를 구하였다. 구조부는 유한요소법을 이용하여 계산하였으며, 유체부는 경계요소법을 사용하여 분석하였다. 탄성변형과 강체운동으로 인한 동적응답을 수치적으로 분석하였으며, 파장, 수심, 파향, 구조물의 강성 요소를 고려하여 규칙파에 대한 응답을 해석하였다. 연구의 결과, L/λ 1.5를 기준으로 응답이 변화하였고, 입사파의 방향에 따라 비틀림 현상이 나타났다. L/λ=8.0의 경우 수심이 증가할수록 입사측에서의 응답이 증가하는 경향이 나타났고, 강성의 변화에 따라 수직변위진폭의 피크점이 좌우로 이동하였다. In this study, we proposed a pier of pontoon-type, “Very Large Floating Structure” (VLFS), with the length of 500m, breadth of 200 m and height of 2 m in Yeosu domestic port. Since this structure ought to endure wave loads for long periods at sea, it is essential to analyze the wave response characteristics. Direct-method is used to analyze the fluid-structure problem and the coupled motion of equation is used to obtain response results. The structural part is calculated by using finite element method (FEM) and the fluid part is analyzed by using boundary element method (BEM). Dynamic responses caused by the elastic deformation and rigid motion of structure are analyzed by numerical calculation. To investigate response characteristics of the pier in regular waves, several factors such as the wavelength, water depth, wave direction and flexural rigidity of structure are considered. As a result, wave response of pier changed at the point of L/λ 1.5 and represented the torsional phenomenon according to the various incident waves. And the responses showed increasing tendency as the water depths increase at the incident point in case of L/λ=8.0 and peak point of vertical displacement amplitude moved from side to side as the flexural rigidity of structure changes.

국내 도시지역의 지반응답특성 거동 평가

신대섭(Dea-Sub Shin),김후승(Hu-Seung Kim) 한국산학기술학회 2017 한국산학기술학회논문지 Vol.18 No.6

지진 발생시 지반조건에 의하여 지반운동에 영향을 받으며 내진설계시 지반특성을 고려한 부지응답특성 평가를 수행해야한다. 국내 내진설계기준의 설계지진력을 결정하는 부분은 미국내진설계기준(UBC-1997)을 차용하여 사용하고 있다. 국내 지반특성과 다른 미국의 지반특성에 적합하게 만들어진 기준을 그대로 사용하는 경우 과다 또는 과소 설계의 원인이 될 수 있다. 따라서 국내지반특성에 적합한 설계응답스펙트럼의 개선이 중요하다. 그래서 본 연구에서는 국내 도시지역의 158개 지반을 선정하여 미국 서부지역의 지반 특성과 비교하고 부지응답을 수행하였다. 158개의 지반을 내진설계기준에서 제시하는 분류방법을 이용하여 분류하였을 때 SB에 해당하는 지반이 37개, SC은 107개, 지반 SD은 14개로 분류되었다. 각 분류된 지반과 7개의 입력지진파를 토대로 해석을 수행하였으며, 내진설계기준과 비교 분석 결과, 국내 설계응답스펙트럼은 국내의 도시지역의 지반특성에 비하여 단주기 영역의 증폭을 과소평가하고 장주기 영역의 증폭을 과대평가하는 것으로 나타났다. 158개의 해석대상부지 중에서 77%정도를 차지하는 지반 SC, SD의 결과에서 설계응답스펙트럼과 큰 차이가 발생한다는 것은 국내 내진설계기준에 제시되어있는 증폭계수를 국내 지반특성에 적합하도록 재산정 할 필요성이 있다는 것을 보여준다. When an earthquake occurs, it is necessary to evaluate the site-specific ground response while considering ground characteristics in seismic design. The design seismic force of Korean seismic design criteria is borrowed from the Uniform Building Code(UBC-1997). However, the criteria are based on the ground characteristics of the United States, which are different from the ground characteristics in Korea, and using them could cause over-orunder-designing. Therefore, it is important to develop a proper design response spectrum for Korean ground characteristics. In this study, 158 ground sites in Korean urban areas were selected and compared to those in the western part of the United States, and their site-specific ground responses were analyzed. The classification standard in the seismic design criteria classifies the 158 sites into 37 sites, 107 sites, and 14 sites. Using 7 earthquake inputs, the criteria were compared for each group.The Korean design response spectrum underestimates the amplification of the short-period range and overestimates the amplification in the long-period range. There were large differences in the results of the and sites,which accountfor 77 percent of the 158 sites. Therefore, there is a need to modify the amplification factor in the Korean seismic criteria to properly reflect Korean ground characteristics.