• Journal of Veterinary Clinics
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• v.29 no.1
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• pp.68-77
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• 2012

Whenever planning a study design or preparing a research proposal it is highly recommended that investigators decide the optimum sample size that is required to yield an outcome of interest with a predetermined level of precision. This is because that, all else being equal, if a study with less than the optimum sample size would not detect the significance of differences in reality, and similarly, if a study with more than the optimum sample size will be costly. For these reasons, the majority of peer reviewed biomedical journals assess the adequacy of sample size requirements. The calculated sample size is used as a target number of samples to be collected to provide an estimate of the parameter with the desired and predetermined level of accuracy, and the sample size is a major determinant of the probability of detecting diseased animals from the population. There is no single method of calculating sample size for any given study design. In this context, the purpose of this article is to provide a collection of formulas and examples for some typical situations likely to be encountered in veterinary clinical practice and to highlight the importance of performing prospective sample size calculations when planning a research. Specifically, this paper is concerned with the basic principle of sample size calculation, and considerations for methodological applications were illustrated for a given data set. Also included in this paper is factors influencing sample size calculations using a statistically valid techniques. Appropriate methods to consider these factors are presented.

• East Asian Economic Review
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• v.27 no.3
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• pp.213-242
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• 2023

This paper investigates whether the price of cryptocurrency is determined by the US dollar index, the price of investment assets such gold and oil, and the implied volatility of the KOSPI. Overall, the returns on cryptocurrencies are best predicted by the trading volume of the cryptocurrency both in-sample and out-of-sample. The estimates of gold and the dollar index are negative in the return prediction, though they are not significant. The dollar index, gold, and the cryptocurrencies seem to share characteristics which hedging instruments have in common. When investors take notice of the imminent market risks, they increase the demand for one of these assets and thereby increase the returns on the asset. The most notable result in the out-of-sample predictability is the predictability of the returns on value-weighted portfolio by gold. The empirical results show that the restricted model fails to encompass the unrestricted model. Therefore, the unrestricted model is significant in improving out-of-sample predictability of the portfolio returns using gold. From the empirical analyses, we can conclude that in-sample predictability cannot guarantee out-of-sample predictability and vice versa. This may shed light on the disparate results between in-sample and out-of-sample predictability in a large body of previous literature.

• The Journal of Korean Medicine
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• v.23 no.3
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• pp.85-95
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• 2002

Objectives : Daechu (Dazhui:GV14 (Governor Vessel 14))-point is located between the spinous process of the 7th cervical vertebra and that of the 1st thoracic vertebra. GV14 has been used to treat hypertension, high fever, neck pain, common cold, headache and so on. Hypertension often negatively affects the improvement of stroke patients. We investigated whether wet-cupping at GV14 had any effect of decreasing blood pressure (BP). Methods : In this study, 81 stroke patients were studied, from Oct. 2000 to Sept. 2001. They were composed of a Sample group (n=36) and Control group (n=45). The Sample group (n=36) was divided into Sample-Normal (n=9), Sample-Mild (n=7), Sample-Moderate (n=l1), and Sample-Severe group (n=9). The Control group (n=45) was divided into Control-Moderate (n=34) and Control-Severe group (n=ll). We checked blood pressure 5 times (just before treatment, then after 30,60, 90, and 120min. (2hrs.)) in each sample group and 3 times (baseline, after 30, and after 120min. (2hrs)) in the control group. Results : In a comparison of before-treatment BP and after-treatment BP in the sample group, SBP significantly decreased as time passed, while DBP slightly decreased but not significantly. In comparison of BP differences in each sample subgroup, BP slightly increased in the Sample-Normal group, but significantly decreased in the Sample-Mild, Sample-Moderate, and Sample-Severe groups. In comparison of BP differences between the sample and control groups, SBP and DBP of the sample group definitely decreased more than those of the control group, but not significantly. Conclusions : This study suggests that wet-cupping at GV14 has significant decreasing effectson blood pressure in stroke patients. Accordingly, we hope that this measure will be used more widely as an emergent treatment for increased blood pressure.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.10 no.1
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• pp.1-38
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• 1997

This study was performed to investigate the effects of Kamigyemyoungsan and each compositive herbs on the intravascular coagulation and subcutaneous hematoma. The intravascular coagulation was induced by the injection of endotoxin into the caudal vein of the rats. These rats were treated with endotoxin after administering orally extracts of Kamigyemyoungsan and each compositive herbs. Then the number of platelet, prothrombin time, the concentration of fibrinogen and FDP(fibrinogen degration product), hematocrit and RBC and WBC were measured. The subcutaneous hematoma was induced by the subcutaneous injection of the autologous whole blood to produce clotting in situ in rats. Then the extracts of Kamigyemyoungsan and each compositive herbs were administered orally. The lesions were then dissected and observed. The results were obtained as follows ; 1. The number of platelets of the trial groups was increased as compared with the control group, and revealed significance in sample Ⅰ. 2. The concentration of fibrinogen of the trial groups was increased as compared with the control group, and revealed significance in sample Ⅰ, sampleⅡ and sample Ⅴ. 3. The prothrombin time was shortened significantly in the trial groups, except sampleⅡ and sampleⅣ as compared with the control group. 4. The concentration of FDP decreased in the trial groups, and revealed significance in sample Ⅰ and sample Ⅵ as compared with the control group. 5. The hematocrit significantly increased in sample Ⅰ, sampleⅢ and sample Ⅵ as compared with the control group. 6. The number of RBC significantly increased in sample Ⅵ only as compared with the control group. 7. The number of WBC significantly increased in the trial groups, except sampleⅣ and sample Ⅵ as compared with the control group. 8. Histologically, the lesions in the trial groups showed significantly thinner fibroblastic neomembrane than the control group, except sampleⅢ. According to the above results, it is considered that Kamigyemyoungsan and each compositive herbs have inhibitive effects on the thrombosis and the fibroblastic neomembrane development. Therefore, it seems to be applicable to the diseases related to thrombosis and hematoma.

• School Mathematics
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• v.16 no.4
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• pp.727-743
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• 2014

The concepts of sample and sampling are central to the statistical thinking and foundations of the statistical literacy, so we need to be emphasized their importance in the statistics education. However, many researches which dealt with samples only analyze textbooks or students' responses. In this study, the concept of sample is addressed by a historical consideration which is one aspect of the didactical analysis. Moreover, developing concept of sample is analyzed from the preceding studies about the statistical literacy, considering the sample representativeness and the sampling variability. The results say that the historical process of developing the concept of sample can be divided into three step: understanding the sample representativeness; appearing the sample variance; recognizing the sampling variability. Above all, it is important to aware and control the sampling variability, but many related researches might not consider sample variability. Therefore, it implies that the awareness and control of sampling variability are needed to reflect to the teaching-learing of sample for developing the students' statistical literacy.

• Journal of Sasang Constitutional Medicine
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• v.2 no.1
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• pp.167-178
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• 1990

In order to investigate experimentally the clinical effect of Soyangin-Hyongbangdojoksan (少陽人荊防導赤散) that was prescribed to cure the Bisuhanpyohanbyong (脾受寒表寒病) of Soyangin (少陽人). The author experimented various activities of dried extract from hyongbangdojoksan (Sample-I) and mixed extract of each dried extract of hyongbangdojoksan (Sample-II) by the methods prescribed in the experimental parts. The results summarized as follows. 1. In the acetic acid method experiment, analgesic effect was noted in sample-I & Sample-II. 2. Anti-inflammatory effect on the edema induced by carrageenin was noted in Sample-I. 3. Antipyretic effect is not noted in Sample-I and Sample-II. 4. On urinary volume change and blood electrolyte clearance, the result is not significant, on the contrary the urine electrolyte discharge is effective in Sample-I and Sample-II. According to the above results, the effects based on oriental medical references approximate to the actual experimental results.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1021-1021
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• 2001

Sample presentation, which means how to set samples to an NIR instrument, is very important in Near Infrared (NIR) Spectroscopy. When sample presentation is not suitable for the samples that you use, very good spectra can not be obtained even if you use a sophisticated NIR instrument. In my presentation, various NIR sample presentations for agricultural products such as intact fruits, single grains, vegetable juice and the others will be explained. In case of peaches with thin peel, the fiber optics of Interactance can be used. However, the fiber optics are not suitable for oranges with relatively thick peel. In this case, transmittance method is useful. As for a small sample such as single grains, a specially designed cell is needed. The cell in transmittance mode has been developed and then applied to single kernels of rice and soybean. In this case we also used the fiber optics. As regards liquid type of sample, a cuvette cell made of quartz in transmittance mode is popular. However, it is time-consuming to wash and dry it. In order to compensate this disadvantage the sample presentation using normal test tubes as sample cells have been developed and applied to milk, rumen juice and urine of a milking cow. An individual test tube can be used for each sample if you use the calibration equation with sample cell compensation. The test tube cell has also been applied to spinach juice for determination of undesirable constituents. It is concluded that sample presentation is most important for NIR Spectroscopy.

• The Journal of Korean Medicine
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• v.17 no.2 s.32
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• pp.178-190
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• 1996

This experiment was performed in order to study the effects of Haepyoyijintang on the pulmonary injury caused by $SO_2$. Healthy adult male rats weighting about 250g were divided into 4 groups- the Normal group, the Control group, the group of Haepyoyijintang administration for 5 days after $SO_2$ gas exposure (Sample I ), and the group of Haepyoyijintang administration for 10 days before and for 5 days after $SO_2$ gas exposure (SampleⅡ). The results were obtained as follows; 1. In the total number of leucocyte, Sample I and Sample II decreased significantly compared with Control group. 2. In the erythrocyte sedimentation rate, Sample I and Sample Ⅱ decreased significantly compared with Control group. 3. In the lung weight, Sample I and Sample II decreased significantly compared with Control group. 4. In the lung TBA level, only Sample II decreased significantly compared with Control group. 5. In the tracheal glycoprotein level, Sample I and Sample II decreased significantly compared with Control group. According to the above results, Haepyoyijintang has significant effects on the pulmonary injury caused by $SO_2$ in rats.

• The Journal of Korean Medicine
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• v.18 no.1
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• pp.344-356
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• 1997

This experiment was performed in order to study the clinical effect of Sojadodamgangkitang on the pulmonary injury caused by $SO_2$. Healthy adult male rats weighing about 250g were divided into 4 groups-the Normal group, the Control group, the group of Sojadodamgangkitang administration for 5 days after $SO_2$ gas exposure(Sample I), and the group of Sojadodamgangkitang administration for 10 days before and for 5days after $SO_2$ gas exposure(Sample II). The results were obtained as. follows; 1. In comparison with Control group, Sample I and Sample II were revealed significant effect on the total number of leucocyte. 2. In comparison with Control group, Sample I and Sample II were revealed significant effect on. the erythrocyte sedimentation rate. 3. In the effect on the lung weight, Sample I and Sample II were revealed significantly. 4. In the effect on the lung TBA level, only Sample II was revealed significantly. 5. In the effect on the tracheal glycoprotein level, Sample I and Sample II were revealed significantly. According to above results, Sojadodamgangkitang had significant effect on the pulmonary injury caused by $SO_2$ in rats.

• Magazine of the Korean Society of Agricultural Engineers
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• v.20 no.3
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• pp.4750-4770
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• 1978

Under the various variations of the sample thickness, the load increment ratio and the load increment duration, this consolidation test of the clay in the Asan Bay was tried for the comparison with the standard consolidation test. The results gained are as follows; 1. The void ratio variations of the leached-clay samples were increasingly high, according as the sample thickness thinned and the load increment duration and the laod increment ratio increased. 2. The coefficient of consolidation were increased with the increment of the sample thickness, of the load increment ratio and of the load increment duration. Near the pre-consolidation load, the coefficient of secondary consolidation had the maximum value and lessened with the increment of the sample thicknss, and of the load increment duration 3. The value of the pre-consolidation load increased in proportion to the increment of the sample thickness and the decrease of the load increment ratio and the load increment duration. 4. The compression indices increased as the increment of load increased and decreased as the sample thickness increased. 5. The initial compression ratio increased as the sample thickness, the load increment ratio and the load increment duration decreased. The ratio of primary compression to the secondary decreased with the increment of the sample thickness and of the load increment ratio. 6. The time at the completion of psimary consolidation increased with the increment of the sample thickness and of the consolidation load, and with the decrease of the load increment ratio. 7. The compression indicses increaed as the sample thickness lessened and decreased as the load increment ratio increased. The coefficient of consolidation increased according as the sample thickness, the load increment ratio and the load increment duration went up. The settlement at the construction site should be calculated highly in proportion as the sample thickness lessened and the load increment ratio increased. The consolidation ratio is thought to be accelerated if the sample thickness and the load increment ratio becomes higher and the load increment duration longer.