• The Korean Journal of Physiology
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• v.14 no.1
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• pp.1-5
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• 1980

This study was under taken to investigate the influences of predictable or unpredictable stress upon gastric ulceration, and the hippocampectomy upon the ulceration order the stressful conditions. Sixty male albino rats(Sprague-Dawley strain) were divided equally into 3 groups: One was the hippocampal group(N=20) which received hippocampal ablation by suction, another was the cortical control group(N =20) which received partial cortical ablation over the hippocampus, and a third was the normal control group(N=20). Each group was further divided into two subgroups: One was the predicted subgroup(N=10) in which animals could predict the imminent stressful stimuli by hearing a sound(1,000 Hz, 2 sec in duration) 3 sec before the onset of the stress, and the other was the unpredicted subgroup(N=10). After starvation for 24 hours, but water ad libitum, each rat received the electric stimulation(3 mA, 60 Hz, 2 sec in duration, and once per minute in average) for 6 hours via a pair of electrodes attached on the tale. The electric stimulation served as the stress causing the gastric ulcer. Five hours after completion of stimulation, the stomach filled with the physiological saline was removed under deep anesthesia and spread out on a small glass plate. The numbers of the ulcer in each stomach were counted and the shape was examined under the dissecting microscope. Results obtained were as follows: 1. The mean numbers of the ulcer of the predicted subgroups were significantly larger than those of the unpredicted subgroups in the normal control and the cortical control groups, but there was no difference between the values of the two subgroups in the hippocampal group. 2. The mean numbers of the ulcer of the predicted subgroups in the normal control and the cortical control groups were larger(but not significant) than that in the hippocampal group. It is inferred from the above results that the prediction of the stress strengthens the effect of the stress on the gastric ulceration, and the hippocampus facilitates the effect of the prediction of the stress.

• The Journal of the Korea Contents Association
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• v.22 no.7
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• pp.276-289
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• 2022

The purpose of this study is to examine the impact of leisure activities on middle school and high school students' adjustment to school lives and, in the relationship between their leisure activities and adjustment to school lives, review the mediating effect of psychological happiness and academic stress. For this study, middle school and high school students of the schools located in Seoul and Gyeonggi areas were surveyed over two weeks from November 1 to November 15, 2021, followed by empirical analysis. The findings of this study were as follows; First, the leisure activities of teenagers had a positive impact on their psychological happiness. Second, the leisure activities of teenagers had a negative impact on academic stress. Third, the leisure activities of teenagers had a positive impact on school life adjustment. Fourth, the psychological happiness felt by teenagers had a positive impact on the adjustment to school lives. Fifth, the academic stress of teenagers had a negative impact on school life adjustment. Sixth, in the relationship between leisure activities and school life adaptation, psychological happiness and academic stress had significant mediating effects. The implication of this study is that it provided theoretical and empirical data for developing a strategy to help teenagers adapt to school and cope with school stress with sound leisure activities and high happiness.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.3
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• pp.208-213
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• 2012

With great advancement of the automobile functions, environmental factors become important performances, especially noise. This paper investigates noise sources of outer rotor type BLDC motor using in the air-conditioner of the automobiles. To this end, this paper is analyzed two viewpoints, structural and electromagnetic causes. Structural analysis is conducted through modal test and analysis. For modal analysis, 3D finite element analysis is carried out using commercial program ansys. Electromagnetic causes are analyzed from local force that is computed by Maxwell stress tensor method. Local force excites structure of motor directly. Finally, correlation analysis is performed to determine effect between noise causes.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.1181-1184
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• 2001

This study was performed FEM analysis of RC beams strengthened with CPS, in order to verify the effect strengthened of the loading situation. By load-deflection curve, It was not different that max capacity of RF2-L0 strengthened with CFS on the sound and RF2-L60 strengthened with on the 60% loading situation of service load. When RC beam was shortly strengthened with CFS, bond element of beam on the end was ripped off. Because stress was concentrated on bond element of beam on the end.

• Transactions of the Korean Society of Mechanical Engineers
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• v.7 no.2
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• pp.145-152
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• 1983

An adhesively bonded anisotropic structure containing a part-through crack subjected to in-plane mixed mode deformations is investigated. The problem is reduced to a pair of Fredholm integral equations of the second kind by mathematical analysis. By solving these equations numerically stress intensity factors k$_{1}$ and k$_{2}$ are presented. Two cases are considered with respect to fiber orientations. Case one is to fix the fiber orientations of sound plate bonded to cracked plate with various fiber orientations. The other is to vary fiber orientations for both plates. As boundary conditions, tension and shear loading respectively, are applied to bonded anisotropic plates to observe mixed mode deformations.

• Journal of Veterinary Clinics
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• v.35 no.2
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• pp.57-59
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• 2018

A seven-month-old Hanwoo steer was presented immediately after transport with respiratory symptoms including a nasal discharge, depression, and anorexia. Though repeated treatments, bronchopneumonia had not been improved and had persisted for 10 months. Then, obstructive breath sound was heard. A cyst adjacent to the epiglottis could be observed with respiratory endoscopy. Consequently, chronic bronchopneumonia induced laryngeal cyst formation, resulting in obstructive dyspnea. And respiratory endoscopy may be useful for differentiating the causes of dyspnea in bovine clinical practice.

• KIEAE Journal
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• v.5 no.2
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• pp.27-34
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• 2005

The purpose of this study were to examine actual conditions of apartment residents living with their companion animals and to identify their residential stress and needs of planning elements under those conditions. Questionnaire survey was adopted in this study, and 100 cases were used for data analysis. The subjects for this study were limited to the residents breeding pets in their apartments. The results of this study are as follows: Most of the residents share their living spaces with pets together like their family without spatial restrictions. They indicated problems related to breeding pets in their residence such as walking the dog, cleaning home, leaving pets alone, noise and unpleasant smell. However, they didn't seem to be stressed a lot for their living environments. In terms of residential planning elements, floor plans for effective natural ventilation, balcony with sufficient sunlight, sound proof system, easy-maintenance interior material, unlash area, rubbish bin, mechanical ventilation and central vacuum system and safe electric outlet were highly indicated.

• The KSFM Journal of Fluid Machinery
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• v.13 no.2
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• pp.18-23
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• 2010

This paper presents a procedure for the aerodynamic and aeroacoustic characteristics of a sirocco fan. For the aerodynamic and aeroacoustic analyses of the sirocco fan, three-dimensional steady and unsteady Reynolds-averaged Navier-Stokes equations are solved with a shear stress transport turbulence model for turbulence closure. The flow analyses were performed on a hexahedral grid using a finite-volume solver. The validation of the numerical results is performed by comparing with experimental data for the pressure, efficiency and power. The internal flow analyses of the sirocco fan are performed to understand the unstable flow phenomenon on the casing for the wall pressure and internal flow characteristics at each position. It was found that fluctuation of pressure and locally concentrated noise source are observed near the cut-off and expansion regions of the casing.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.347-351
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• 1997

A micromachined piezoelectic cantilever transducer,which works both as a microphone and as a microspeaker,has been fabricated and tested. The 2000*2000*3.mu.m .sap2. cantilever has oxide(ZnO)piezoelectric thin film on a supporting layer of low-pressure chemical-vapor-deposited(LPCVD)low-stress siliconnitride. A highlight of the fabrication process which may also be relevant for other micromachined stuctures is the technique for producing a flat,multilayer cantilever. The measured microphone sensitivity is fairly constant at 2 mV/.mu.bar in the low frequency range and rise to 20 mV/.mu.bar at the lowest resonant frequency of 890 Hz. The 2 mV/.mu.bar sensitivity is the highest report to data for a microphone with a micromachined diaphragm. When measured into a 2 cm/sap3 coupler with 4V (zero-park)drive,the microspeaker output sound pressure level(SPL) is 75 dB at 890 Hz. It increases to approximately 100dB SPL at 4.8kHz with 6V(zero-park)drive. The measured microphone frequency response agrees well with the results of an ABAQUS simulation.

• MALSORI
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• no.19_20
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• pp.43-57
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• 1990

The teaching of pronunciation is one of the areas in which linguistic phonetics can play an extremely useful role. This paper is concerned with the application of the results of my phonetic research to the actual teaching of Korean standard pronunciation with special reference to speech rhythm. It has been found that Korean words and utterances of various lengths are pronounced in standard Korean with one of the four main rhythmic patterns, each containing a strong stress. Unless we get the rhythmic patterns right in pronouncing Korean words and utterances, therefore, the resulting pronounciation is bound to sound dialectal or incorrect and in many instances even unintelligible to listeners. Hence the undeniable need to devise a useful technique to teach the Korean speech rhythm in a systematic way. In this paper each of the four main rhythmic patterns is presented and elaborated with sample examples taken from the living Korean. It is hoped that these examples of words and utterances can be used at the same time as useful pronunciation drill material not only for Koreans with dialectal background but also for foreign learners of Korean.