• Communications for Statistical Applications and Methods
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• v.31 no.1
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• pp.129-142
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• 2024

In various industries, especially manufacturing and chemical industries, it is often observed that the distribution of a specific process, initially having followed a normal distribution, becomes skewed as a result of unexpected causes. That is, a process deviates from a normal distribution and becomes a skewed distribution. The skew-normal (SN) distribution is one of the most employed models to characterize such processes. The shape of this distribution is determined by the asymmetry parameter. When this parameter is set to zero, the distribution is equal to the normal distribution. Moreover, when there is a shift in the asymmetry parameter, the mean and variance of a SN distribution shift accordingly. In this paper, we propose procedures for monitoring the asymmetry parameter, based on the statistic derived from the noncentral t-distribution. After applying the statistic to Shewhart and the exponentially weighted moving average (EWMA) charts, we evaluate the performance of the proposed procedures and compare it with previously studied procedures based on other skewness statistics.

• Steel and Composite Structures
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• v.35 no.4
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• pp.475-494
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• 2020

Presented are experimental results from 24 full-scale push test specimens to study the behaviour of composite beams with trapezoidal profiled sheeting laid transverse to the beam axis. The tests use a single-sided horizontal push test setup and are divided into two series. First series contained shear loading only and the second had normal load besides shear load. Four parameters are studied: the effect of wire mesh position and number of its layers, placing a reinforcing bar at the bottom flange of the deck, normal load and its position, and shear stud layout. The results indicate that positioning mesh on top of the deck flange or 30 mm from top of the concrete slab does not affect the stud's strength and ductility. Thus, existing industry practice of locating the mesh at a nominal cover from top of the concrete slab and Eurocode 4 requirement of placing mesh 30 mm below the stud's head are both acceptable. Double mesh layer resulted in 17% increase in stud strength for push tests with single stud per rib. Placing a T16 bar at the bottom of the deck rib did not affect shear stud behaviour. The normal load resulted in 40% and 23% increase in stud strength for single and double studs per rib. Use of studs only in the middle three ribs out of five increased the strength by 23% compared to the layout with studs in first four ribs. Eurocode 4 and Johnson and Yuan equations predicted well the stud strength for single stud/rib tests without normal load, with estimations within 10% of the characteristic experimental load. These equations highly under-estimated the stud capacity, by about 40-50%, for tests with normal load. AISC 360-16 generally over-estimated the stud capacity, except for single stud/rib push tests with normal load. Nellinger equations precisely predicted the stud resistance for push tests with normal load, with ratio of experimental over predicted load as 0.99 and coefficient of variation of about 8%. But, Nellinger method over-estimated the stud capacity by about 20% in push tests with single studs without normal load.

• Journal of Microbiology and Biotechnology
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• v.24 no.11
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• pp.1551-1558
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• 2014

The esterase gene Est8 from the thermophilic bacterium Bacillus sp. K91 was cloned and expressed in Escherichia coli. The monomeric enzyme exhibited a theoretical molecular mass of 24.5 kDa and an optimal activity around $50^{\circ}C$ at pH 9.0. A model of Est8 was constructed using a hypothetical YxiM precursor structure (2O14_A) from Bacillus subtilis as template. The structure showed an ${\alpha}/{\beta}$-hydrolase fold and indicated the presence of a typical catalytic triad consisting of Ser-11, Asp-182, and His-185, which were investigated by site-directed replacements coupled with kinetic characterization. Asp-182 and His-185 residues were more critical than the Ser-11 residue in the catalytic activity of Est8. A comparison of the amino acid sequence showed that Est8 could be grouped into the GDSL family and further classified as an SGNH hydrolase. Est8 is a new member of the SGNH hydrolase subfamily and may employ a different catalytic mechanism.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.1
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• pp.67-73
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• 1999

The insulin-like growth factor (IGF)s are believed to one of several growth factors that play an adjunctive role in ovarian follicular development. These factors circulate bound to a family of IGF-binding protein (IGFBP)s. It is known that circulating IGFBPs are involved in the transport of IGFs to tissues and modulate IGFs actions at local tissue. The purposes of this study were to evaluate changes in serum IGFBPs profiles during normal ovulatory menstrual cylce and to compare serum IGFBPs profiles in periovulatory phase of between normal ovulatory menstrual cylce and controlled hyperstimulated cycle. Fasting blood samples were obtained from 15 normal healthy women throughout normal ovulatory menstural cyle and on the day of aspiration of oocyte from 10 patients undergoing ovarian hyperstimuation for in vito fertilization-embryo transfer. Serum IGFBP-1 - IGFBP-4 were measured by western ligand blot and immunoprecipitation. Serum $17{\beta}$-estradiol was determined by radioimmunoassay. Type and molecular weight of serum IGFBP did not changed during normal ovulatory menstural cycle. No significant variation in the relative proportion and level of each IGFBP was found throughout normal ovulatory menstural cyle. Also, the relative proportion and level of each IGFBP did not correlated with serum $17{\beta}$-estradiol level. There was no significant difference in the relative proportion and level of each serum IGFBP between on the day of ovulation in normal ovulatory menstrual cylce and on the day of aspiration of oocyte in controlled hyperstimulated cycle. Our data indicate that IGFBPs have regulatory functions in ovary through an paracrine and autocrine rather than endocrine mechanism during normal ovulatory menstural cycle.

• Korean Journal of Computational Design and Engineering
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• v.13 no.1
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• pp.1-7
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• 2008

Data compression becomes increasingly an important issue for reducing data storage spaces as well as transmis-sion time in network environments. In 3D geometric models, the normal vectors of faces or meshes take a major portion of the data so that the compression of the vectors, which involves the trade off between the distortion of the images and compression ratios, plays a key role in reducing the size of the models. So, raising the compression ratio when the normal vector is compressed and minimizing the visual distortion of shape model's shading after compression are important. According to the recent papers, normal vector compression is useful to heighten com-pression ratio and to improve memory efficiency. But, the study about distortion of shading when the normal vector is compressed is rare relatively. In this paper, new normal vector compression method which is clustering normal vectors and assigning Representative Normal Vector (RNV) to each cluster and using the angular deviation from actual normal vector is proposed. And, using this new method, Visually Undistinguishable Lossy Compression (VULC) algorithm which distortion of shape model's shading by angular deviation of normal vector cannot be identified visually has been developed. And, being applied to the complicated shape models, this algorithm gave a good effectiveness.

• Journal of Environmental Health Sciences
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• v.7 no.1
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• pp.59-62
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• 1981

We have performed 324 specimens' urobilinogen determinations(Healthy normal 219 & out-or in-patients 105) for the purposs of defining accurate & precise methods in semi-quantitative techniques. As shown on Table 1 through 5 & Fig.1 to 3, normal person's titer is concentrated in 1:40, 1:80, 1:20 & 1:10 respectively and majority of patients' titer is 160. The concentration diagram on Fig. 2 is seen for the normal person and patient's titer is nearly normal distribution scattered from 0.475mg/dl of median throughout the whole area (0.225-0.625). From Fig. 5 I have found that semi-quantitative titer is much different from the true value by electrical measurements. I am proposing of taking photoelectric quantitative methods for semiquantitative methods.

• Phonetics and Speech Sciences
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• v.1 no.4
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• pp.147-157
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• 2009

The purpose of the study is to develop the normal voice database and to analyze the acoustic characteristics of Korean adults' voices by gender using MDVP. Eight categories in the 34 parameters of MDVP were analyzed in the voices of 170 Korean normal adults taken from /a/ vowel. Among them, Fundamental Frequency Parameters and Frequency Perturbation Parameters were significantly different by gender. In addition, Fundamental Frequency Parameters of our data were remarkably different from the data suggested in the MDVP program which currently used in clinics. Therefore, the data obtained from the current study can be effectively used for the diagnosis of voice disorders of Korean adults as the standard parameter values of MDVP.

• Journal of the Korea Safety Management & Science
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• v.3 no.3
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• pp.175-190
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• 2001

We propose, a new process capability index $C_{psk}$(WV) applying the weighted variance control charting method for non-normally distributed. The main idea of the weighted variance method(WVM) is to divide a skewed or asymmetric distribution into two normal distributions from its mean to create two new distributions which have the same mean but different standard deviations. In this paper we propose an example, a distributions generated from the Johnson family of distributions, to demonstrate how the weighted variance-based process capability indices perform in comparison with another two non-normal methods, namely the Clements and the Wright methods. This example shows that the weighted valiance-based indices are more consistent than the other two methods in terms of sensitivity to departure to the process mean/median from the target value for non-normal processes. Second method show using the percentage nonconforming by the Pearson, Johnson and Burr systems. This example shows a little difference between the Pearson system and Burr system, but Johnson system underestimated than the two systems for process capability.

• The Korean Journal of Food And Nutrition
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• v.12 no.5
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• pp.496-501
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• 1999

Albinism is a phenomenon that color of the body surface is changed to white orfaint brown from the specific color to the species by difficiency of pigments due to mutation or disease. This study was undertaken to investigate the experimental basis on the appearance of albinism in cultured flounder Paralichthys olivaceus. The skin and muscle from the normal and albinic flounder were used by measuring contents of amino acid free amino acid. The results were summarized as follows: Contents of amino acid in theskin and muscle are different from normal and albinic flounder. Phenolic and sulfuric amino acids in the skin of normal flounder were 2 times those of albinic ones. Especially tyrosine contents of the skin in normal flounder were 24 times higher than those. Methionine was 26 times higher than those Phenylalanine was 1.6 times higher. In free amino aicd phosphoserine and phosphoethanolamine were a little higher than that ones. The melanin formation of the skin in flounder was affected by substrates such as phenolic amino acid and cofactor such as sulfuric amino acid.

• Journal of Nutrition and Health
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• v.35 no.7
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• pp.729-736
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• 2002

The purpose of this study was to investigate the effects of glucuronic acid (isolated from xylan) on antioxidative defense system in rat after aerobic exercise. The glucuronic acid was isolated from xylan. Sprague-Dawley male rats weighing 150$\pm$10 g were randomly assigned to one normal group and three exercise training groups. Exercise training groups were classified to T (glucuronic acid free diet), TU (250 mg glucuronic acid/kg bw) and 2TU (500 mg glucuronic acid/kg bw) according to the level of glucuronic acid supplementation before exercise training. The experimental rats in exercise training groups (T, TU and 2TU) were exercised on glucuronic acid supplementation or rats in normal group (N) were confined in cage for 4 weeks. And rats were sacrificed with an overdose of pentobarbital injection just after running. Body weight, food intakes and food efficiency ratio (FER) were lower in the exercise training group than in the normal group. White gastrocnemius xanthine oxidase (XOD) activity in the T group was 85% greater than that of the normal group, whereas in the TU and 2TU groups it did not differ from the normal group. White gastrocnemius superoxide dismutase (SOD) activity in T group, that was decreased by 22% compared with that of N group, but those of TU and 2TU groups were increased by 38% and 42%, respectively, compared with that of T group. White gastrocnemius glutathione peroxidase (GSHpx) activity in T group, that was decreased by 42% compared with that of N group, but those of TU and 2TU groups were increased by 67% and 68%, respectively, compared with that of T group. Glutathione S-transferase (GST) activity of white gastrocnemius in N group was not significantly different from that in the T and TU groups, but 2TU group were increased by 12%. Contents of thiobarbituric acid reactive substance (TBARS) in T group was increased by 54%, compared with that of normal group but those of TU group and 2TU group were lower 44% and 36% than that of T group. In conclusion, the effects of glucuronic acids in exercise training rats would appear to reduce peroxidation of tissue as an antioxidative defense mechanism.