• Proceedings of the Korean Magnestics Society Conference
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• 2003.06a
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• pp.260-261
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• 2003

It is recognized that the magnetization reverses with a sequence of discrete and jerky jumps, known as the Barkhausen effect. Recently, interest in the Barkhausen effect has grown as it is a good example of dynamical critical behavior, evidenced by experimental observation of a power law distribution of the Barkhausen jump size. So far, most experimental studies have been carried out on bulk samples using a classical inductive technique, which is difficult to apply to thin film samples mainly due to the ]ow signal intensity. For this reason, very few experiments have been done on two-dimensional ferromagnetic thin films. In this talk, we report a direct domain observation of Barkhausen avalanche at criticality in Co and MnAs thin films investigated by means of a magnetooptical microscope magnetometer (MOMM), capable of time-resolved domain observation with an image grabbing rate of 30 frames/s in real time. In Fig. 1, we demonstrate a series of six representative domain-evolution patterns of 25-nm Co film observed successively by means of the MOMM, where one can directly witness Barkhausen avalanche.

• Korean Journal of Veterinary Research
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• v.22 no.1
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• pp.31-36
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• 1982

This study was taken to clarify the clinical signs and macroscopical lesions of pigs naturally infected with hog cholera. The clinical and macroscopical observation on the natural cases of hog cholera and experimental cases inoculated with ALD Virus and isolated virus strains were carried out. The results obtained are as follow; In clinical inspection of the natural cases, diarrhea (73.1%) blotching of ear (50.0%), staggering (42.3%), erythema of skin (40.0%), constipation (38.5%), conjunctivitis (32.7%) and dyspnea (30.8%) were observed. Dyspnea, constipation and erythema of skin were observed mainly in the experimental cases, however, staggering and conjunctivitis in pigs infected with ALD virus were found and convulsion and hemorrhage of skin of pigs infected with isolated virus were seen, respectively. The gross lesions of natural cases were hemorrhage of lymph node (82.5%), enteritis and hemorrhage of large intestine (65.0%), splenic infarction (57.5%), pneumonia (55.0%), gastritis and hemorrhage (52.5%), cardiac hemorrhage (40.0%) and renal petechiation (37.5%), while in the experimental cases, hemorrhage of lymph node, pneumonia, gastritis and hemorrhage, enteritis and hemorrhage of laryge intestine and splenic infarction were seen mainly.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.04a
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• pp.336-339
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• 2001

In this study an experimental investigation was conducted to find the grinding characteristics of ceramics, as compared to STDll and SUS304 materials. The grinding force and the microscopic observation of the workpieces were obtained in surface grinding. It has been found that the grinding force of ceramics is relatively low as compared to that of steels and that CBN wheel has an excellent performance.

• Journal of Korea Water Resources Association
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• v.55 no.12
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• pp.1149-1154
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• 2022

The purpose of this research is to select representative observation stations for winter observation equipment performance tests and to present indoor and outdoor conditions for performance tests by considering snowfall, snowfall days, latitude, and altitude distribution for observation stations operated by the Korea Meteorological Administration. Using the snowfall data observed during the winter for 30 years (1981-2010), ten representative observation stations are selected to consider the classification of snowfall days by class, latitude, and altitude distribution of observation stations. As a result of analysis, the suitable point for outdoor experiments was selected as Daegwallyeong, the average number of snowfall days and snowfall days of 5cm or more were 57.5 and 13.2 days, respectively. The indoor experimental conditions are considered to be suitable under temperatures of -15 to 5℃ and humidity of 50% or higher. Results of this research can be used as basic information for conditions and test beds for performance tests of equipment that can respond to heavy snow disasters in winter.

• Journal of Oral Medicine and Pain
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• v.14 no.1
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• pp.123-131
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• 1989

The purpose of this study is to evaluate an effect of levamisole on the chemical crcinogenesis in the submandibular salivary gland of rats through histopathologic observation. 60 male Sprague Dawley rats were employed in this study, divided into one control and two experimental groups. An pellet of 5 mg of 9, 10-dimethyl-1,2-benzathracene(DMBA) powder was implanted into submandibular salivary gland of each animal among 20 in control. And each animal among 20 in experimental group 1 received 0.7 mg of levamisole hydrochloride orally every day starting at the beginning of the fifth week after DMBA implantation under the same methods as in control. And each animal among 20 in experimental group 2 received the same treatment as in control at the beginning of the fifth week after oral administration of levamisole hydrochloride under the same method as experimental group 1. Each 5 animals in control at the end of 2nd, 4th, 6th 8th, week after experiments, and each 10 animals in experimental group 1,2 at the end of 6th, 8th week after experiments were sacrificed at random. Also the specimens from experimental sites of submandibular salivary glands were routinely processed for histopathologic observation under Hematoxilin-eosin(H-E) staining. The obtained results were as follows : 1. In control, generally, the glandular ductal cell showed the tendency of dysplasia or malignancy with progression of experiment. 2. In experimental group 1, generally, the dysplasia or malignancy of the glandular ductal cell was less prominent than in control, while the lymphocyte infiltration and fibrosis were prominent. 3. In experimental group 2, generally, the dysplasia of the glandular ductal cell was significantly less prominent than in control, while the fibrosis was prominent. 4. Under above results levamisole was thought to delay or prevent the chemical carcinogenesis in the submandibular salivary gland.

• Journal of Pharmacopuncture
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• v.1 no.1
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• pp.1-21
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• 1997

In order to investigate experimentally that effect of Moschus, Bovis Calculus, Ursi Fel aqua-acupuncture on acutely damaged liver of rats induced by radix aconiti, the author gave Moschus, Bovis Calculus, Ursi Fel aqua-acupuncture according to method of manufacture stimulation to corresponding points, Kan-su(B18) and Ki-mun(Liv14), and carried out hematological, serological observation. Experimental groups were divided into 2 group : the one group was injected with extracted solution prepared by distillation method (A aqua-acupuncture treatment group), the other group was injected with extracted solution prepared by alchol extraction method (B aqua-acupuncture treatment group). The following results were obtained : 1. WBC level was decreased significantly in the experimental groups at 12, 24 and 48 hours as compared with the control group. RBC and hemoglobin levels were not changed significantly in the experimental groups. 2. Total cholesterol level was decreased significantly in the experimental groups at 12, 24 and 48 hours as compared with the control group. ALP level was decreased significantly in the experimental groups at 6 and 24 hours as compared with the control group. ${\gamma}-GTP$ level was decreased significantly in the experimental groups at 6, 12, 24 and 48 hours as compared with the control group. 3. GOT level was decreased significantly in the experimental groups at 6 and 12 hours as compared with the control group. GPT level was decreased siginificantly in the experimental groups at 12, 24 and 96 hours as compared with the control group. According to the above findings, it is considered that Moschus, Bovis Calculus, Ursi Fel aqua-acupuncture has effects of recovery of acutely damaged liver.

• Toxicological Research
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• v.6 no.1
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• pp.1-12
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• 1990

Effect of red ginseng treatment on experimentally induced hyperkeratosis was investigated by light microscopic observation scanning electron microxcope (SEM) examination, epidermal enzyme activities nd lipid contents. Both light microscopic observation and SEM examination showed that hexadecane induced epidermal hyperplasia, hypertrophy and hyperkeratosis by increasing the numbers as well as the sizes of epidermal cells including desquamating horny cells. The superficial horny cells were protruded around the base of hair shaft. Among red ginseng components, only saponin treatment inhibited epidermal hyperplasia and hyperkeratosis by reducing the thickness of epidermis and arranging the cornified cells. Saponin from korean red ginseng inhibited abnormally increased epidermal LDH, ICD and G6PDH activities and reduced the contents of epidermal lipids induced by hexadecane. It seems that red ginseng saponin has preventive effect on experimental hyperkeratosis possibly by controlling the enzyme activities involved in epidermal cellular metabolism, resulting in reduced amounts of abnormal epidermal lipids.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.11
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• pp.41-44
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• 1995

A numerical technique is employed to simulate the flow patterns in the human carotid artery and a phantom of the carotid artery made of acrylic material is used to observe the flow phenomena in the carotid artery. For numerical analysis the idealized geometric shape of the carotid artery is constructed to portray the phantom. Steady momentum equation is solved by the finite element method and the numerical results are compared with the results of MRA and color Doppler images.

• Journal of The Korean Association For Science Education
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• v.10 no.1
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• pp.33-45
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• 1990

To achieve the aim of science education, it is known that warious teaching, and learning materials should have to be used. As a sub-textbook for primary science education, 'Sil Hum-Kwan Chal (Experiment and Observation), teaching and learing material are developed and using now in science. This material have following characteristics; (a) Soruce-book contains reading materials for additional information, various pictures to enririch the science concepts, and supplementary and enrichment activities. (b) Work-book consists of the detailed procedures of activities of experiments presented in the textbook, student can record the experimental procedures and results. (c) Operational manuals provide operation techniques for experimental equipments which are used in science class. In this study the using status are surveyed for the 3rd grade of primary school, and based on this survey the improvement plan are discussed in view of design, quantity and utility, of sub-textbook.

• Journal of Korean Academy of Nursing
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• v.3 no.1
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• pp.85-95
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• 1972

For the purpose to clarify the effects of nursing, intervention with comfort measures which promote rest, exercise and sleep on the patient′s rehabilitation, this study was carried out on 119 postoperative patients at St. Mary′s Hospital, the National Medical Center and Seoul Red Cross Hospital during the 9 months period from March 1971 to November 1971. In this study one experimental nursing approach was utilized; an emphasis on interpersonal techniques along with physical care-comfort measures. A daily evening care including support and instruction was given to facilitate interaction of nursing to the experimental group by the investigator. For the control group, routine hospital nursing care was performed. The nursing observation was followed for 4 days postoperatively and recorded in check list. The results of the findings were as follows. 1. 3.5% of control group and 32.3% of experimental group got out of bed within 24 hours postoperatively. 38.6% of control group got out of bed within 72 hours postoperatively where only 16.1% of the experimental group did (x$^2$= 19.865, p<0.005). Interaction in nursing is, in turn, significantly more effective than the usual routine care in improving rate of healing. 2. The irritations and tension that may interfere patient′s sleep and rest at night can be reduced to a minimum if nursing environment is better controlled with planned nursing care for individual patient. Various treatments which tend to give patient discomfort may preferably be performed before 6 p.m. if not absolutely indicated. 3. During 4 days of observation the patients without administration of sedatives and analgesics postoperatively were 25.9% in the experimental group where as 10.5% in the control group. The frequency of administration of sedatives and analgesics in average was 1.4 in the experimental group, and 2.0 in the control group. This indicates that not all postoperative discomforts expressed by the patients should be regarded as incision pain, and those discomforts could be relieved to a certain extent by nursing interventions effectively. 4. There were significant differences between the responses to nursing care given in the experimental group and 33% of the control group in average through 4 days of observation responded "good". 3.6% of the experimental group and 17. 1% of the control group responded "poor" in this study. It was recommended that the study be replicated in a more defined and controlled manner. Some alternative areas for investigation were suggested.