• Journal of the Korean Chemical Society
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• v.27 no.5
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• pp.353-360
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• 1983

The adsorption behavior of 8-hydroxyquinoline (8HQ) on Amberlite XAD-4 and-7 resins was investigated by measuring its distribution coefficients under various experimental conditions, such as shaking time, pH and concentration of methanol in the medium. The application of 8HQ-impregnated-XAD resins for the absorption and separation of metal ions was studied. The maximum adsorption of 8HQ on XAD resins was observed in the 30% methanol solution having pH range from 6.0 to 9.0. The impregnation capacities of XAD resins for 8HQ were 3.81${\times}$10-2mmol, 8HQ/g, XAD-4 resins and 2.60${\times}$10-2mmol, 8HQ/g, XAD-7 resin, respectively. The 8HQ-impregnated-XAD resins were stable in pH range from 6.0 to 10.0 and the amount of 8HQ leached from XAD-4 resin by eluting with hydrochloric acid(above 5M) was negligible. The optimum pH range for the adsorption of metal ions on 8HQ-impregnated XAD resin was also 6.0 to 10.0, and the adsorption mole ratio of metal ion to 8HQ were 1 : 2 for Cu(II), Cd(II) and Ni(II), and 1 : 3 for Fe(III) at the above pH range. It was found that the absorbed metal ions on 8HQ-impregnated-XAD resins were recovered quantitatively with 5M HCl and 8HQ-impregnated-XAD-4 resin could be reusable over 5 times without decrease in its impregnation capacity.

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.517-523
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• 1994

The effects of cure kinetics and mechanism of DGEBA(diglycidyl ether of bisphenol A)/MDA(4,4'-methylene dianiline) with SN(succinonitrile) and HQ(hydroquinone) as an additive and accelerator were investigated. Cure kinetics was evaluated by Kissinger equation and fractional-life method through DSC analysis. The activation energy has hydroxyl group as an accelerator, the activation energy and the starting cure-temperature were lower than those of DGEBA/MDA/SN system. Cure mechanism of those systems was investigated through FT-IR according to the various SN contents. The ratio was SN : HQ = 4 : 1. It has been known that the cure reactions of an epoxy-diamine system are composed of primary amine-epoxy reaction, secondary amino-epoxy reaction and epoxy-hydroxyl group reaction. But in DGEBA/MDA/SN system, primary amino-CN group reaction and CN group-hydroxyl group reaction were added to the above mentioned reactions. These reactions attributed to the long main chain and the low crossliking density. And in DGEBA/MDA/SN/HQ system, hydroxyl group of HQ formed a transition state with epoxide group and amime group and also opened the ring of the epoxide group rapidly, then amino-epoxy reaction took place easily.

• PNF and Movement
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• v.19 no.1
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• pp.79-86
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• 2021

Purpose: The purpose of this study was to investigate muscle activity according to knee flexion angle during single-limb-deadlift exercises. Methods: In total, 26 healthy volunteers participated. The single-limb-deadlift consisted of 0˚, 15˚, and 30˚ knee joint bending. The electromyography data were collected from the semitendinosus (SM), the biceps femoris (BF), the rectus femoris (RF), the vastus lateralis (VL), and the vastus medialis (VM). In addition, hamstrings and quadriceps (HQ) ratio was measured during the single-limb-deadlift using electromyography. Results: During the single-limb-deadlift, RF, VL, and VM were significantly higher at 30˚ bending angles compared to muscle activity of 0˚ and 15˚ knee-joint bending. The HQ ratio had significant differences in all three knee joint bending angles. In particular, the single-limb-deadlift carried out to a 30˚ knee-joint bend showed the closest value to 1. Conclusion: The most balanced coactivation ratios were observed during a single-limb-deadlift to a 30˚ knee-joint bend angle. A single-limb-deadlift at a knee-bend angle of less than 30˚ could be used as an exercise to prevent ACL injury. It could also be used for post-injury rehabilitation programs by increasing knee-joint stability.

• PNF and Movement
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• v.17 no.3
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• pp.441-450
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• 2019

Purpose: This study identified the co-activation of quadriceps and hamstring muscles during hamstring strengthening exercises in healthy adults. Methods: Twenty-one participants were required for the present study design to achieve 80% power, 0.8 effect size (η2), and an alpha level of 0.05. Thus, this study recruited 21 healthy adults. All participants performed Nordic exercises, bridge exercises, and one-leg deadlifts randomly. The activity of the rectus femoris, vastus medialis (VM), vastus lateralis (VL), biceps femoris (BF), and semitendinosus (SM) were measured. In addition, the ratios of VM/VL and hamstring/quadriceps (HQ) were measured during the three hamstring strengthening exercises using electromyography. One-way ANOVA was used to compare the co-activation of quadriceps and hamstring muscles in the three exercises. Results: The activity of VM and VL during the performance of one-leg deadlifts was significantly higher than the other two exercises. The BF had significantly higher activity during the Nordic exercises compared to the other two exercises. In addition, the SM activation was significantly greater during Nordic exercises than one-leg deadlifts. Additionally, there was significant difference in HQ ratio among hamstring strengthening exercises. In specific, the one-leg deadlifts yielded a significantly lower HQ ratio. Conclusion: This study revealed that one-leg deadlifts are effective in rehabilitation for anterior cruciate ligament injury. In addition, Nordic exercises can be recommended to facilitate hamstring muscle activation.

• Journal of Korean Library and Information Science Society
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• v.54 no.3
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• pp.81-104
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• 2023

This study is a case study in which collection performance evaluation was attempted using key performance indicators presented by EBSM or collectionHQ, taking three public libraries located in Geumjeong-gu, Busan as examples. Focusing on the collection performance evaluation, which evaluates the performance of the collection, not only the evaluation of individual libraries, but also the differences in the evaluation results of libraries were reviewed. The key performance indicators used are grubby items, dead items, popular author provision, popular subject provision, overstocked subject areas and understocked subject areas. The main analysis results are as follows. First, in the evaluation of the grubby items, the ratio of grubby items out of all items in all three libraries was low. Second, in the case of all dead items, the ratio was high in all three libraries, It exceeded the base value suggested by collectionHQ. Third, the Top 10 popular authors were identified, and there were differences among libraries. Fourth, in the evaluation of provision of popular subject areas, all three libraries had almost no popular subject areas. Fifth, in the evaluation of overstocked subject areas, there was no overstock at Geumsaem Library, but many at Geumjeong Library and Seodong Library. Sixth, in the subject area evaluation of understocked inventory, only Geumsaem Library showed a lack of inventory.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.2
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• pp.163-169
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• 2012

Interferon regulatory factor 6 (IRF6) gene is a member of the IRF-family, and plays functionally diverse roles in the regulation of the immune system. In this report, the 13,720 bp porcine IRF6 genomic DNA structure was firstly identified with a putative IRF6 protein of 467 amino acids. Alignment and phylogenetic analysis of the porcine IRF6 amino acid sequences with their homologies to other species showed high identity (over 96%). Tissues expression of IRF6 mRNA was observed by RT-PCR, the results revealed IRF6 expressed widely in eight tissues. One SNP (HQ026023:1383 G>C) in exon7 and two SNPs (HQ026023:130 G>A; 232 C>T) in the 5′ promoter region of porcine IRF6 gene were demonstrated by DNA sequencing analysis. A further analysis of SNP genotypes associated with immune traits including IFN-${\gamma}$ and IL10 concentrations in serum was carried out in three pig populations including Large White, Landraces and Songliao Black pig (a Chinese indigenous breed). The results showed that the SNP (HQ026023:1383 G>C) was significantly associated with the level of IFN-${\gamma}$ (d 20) in serum (p = 0.038) and the ratio of IFN-${\gamma}$ to IL10 (d 20) in serum (p = 0.041); The other two SNPs (HQ026023:130 G>A; 232 C>T) were highly significantly associated with IL10 level in serum both at the day 20 (p = 0.005; p = 0.001) and the day 35 (p = 0.004; p = 0.006). Identification of the porcine IRF6 gene will help our further understanding of the molecular basis of the IFN regulation pathway in the porcine immune response. All these results should indicate that the IRF6 gene can be regarded as a molecular marker associated with the IL10 level in serum and used for genetic selection in the pig breeding.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.3
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• pp.175-183
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• 2012

Objectives: This study developed a harmonized method for risk assessment based on the Hazard & Risk Evaluation of Chemicals (HREC) according to the Industrial Safety and Health Act (ISHA). Methods: Three preliminary studies, performed during 2010 and 2011 by the Occupational Safety and Health Research Institute and three academic research groups, were compared. The differences in risk assessment, especially in the dose-response assessment method, were analyzed. A new harmonized method for dose-response assessment was suggested and its applicability for the HREC was examined. Results: Considering the various steps of each dose-response assessment, the equivalent steps in quantitative correction, uncertainty factor 2 (UF2) for intra-species uncertainty, and UF3 for the experimental period in the uncertainty correction were relatively high. Using our new method, the total correction values (quantitative correction plus uncertainty correction) ranged from 72~15,789 to 30~60, and the ratio of the threshold limit value (TLV) to the reference concentration decreased from 12.8~1900 to 5.4~11.8. Furthermore, when we performed risk characterization by our new method, hazard quotient (HQ) values for chloroethylene, epichlorohydrin, and barium sulfate became 3.0, 14.1, and 1.13 respectively, whereas three previous studies reported HQ values of 7.1, 4580, and 87.3 considering reasonable maximum exposure (RME) conditions. HQs of the three chemicals were calculated to be 0.6, 2.4, and 0.1 respectively, when compared to their TLVs. Conclusions: Our new method could be applicable for the HREC because the total correction values and the ratio of TLVs were within reasonable ranges. It is also recommended that additional risk management measures be applied for epichlorohydrin, for which the HQ values were greater than 1 when compared with both reference values and the TLV. Our proposed method could be used to harmonize dose-response assessment methods for the implementation of risk assessment based on the HREC according to ISHA.

• Journal of the military operations research society of Korea
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• v.3 no.1
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• pp.51-82
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• 1977

Decision making is a function of many variables, but among these, human burden (soft-ware) and machine burden (hard-ware) are critical. Decision Maker is rather concerned with the soft-ware and just wants to have machine calculate the quantitative arithmetic involved in the decision-making study, because he is responsible for that decision whether or not he knows details about the techniques used by his staffs. From the point of these considerations, computer-assisted war game model has its significance in military decision making. The major outcome of this model is time-phased FEBA movement. FEBA is moved mainly by the ratio of the Index of Combat Effectiveness (ICE). To calculate ICE, Ground Forces are concerning the Index of Firepower (IFP) of individual weapons and in the case of Air Force, sorties are allocated into each sector, and added to the Ground Force IFP. With the ratio of total ICE, FEBA is moved according to the War Game Tables and process is repeated after consideration of casualties. This model is used by IBM-370/135 in MND computer room and also tested by IBM-3741/3717 established at ROKA HQ.

• Communications for Statistical Applications and Methods
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• v.31 no.3
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• pp.279-289
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• 2024

Familial searching is a useful technique in a forensic investigation. Using genetic information, it is possible to identify individuals, determine familial relationships, and obtain racial/ethnic information. The total number of shared alleles (TNSA) and likelihood ratio (LR) methods have traditionally been used, and novel data-mining classification methods have recently been applied here as well. However, it is difficult to apply these methods to identify familial relationships above the third degree (e.g., uncle-nephew and first cousins). Therefore, we propose to apply a stacking ensemble machine learning algorithm to improve the accuracy of familial relationship identification. Using real data analysis, we obtain superior relationship identification results when applying meta-classifiers with a stacking algorithm rather than applying traditional TNSA or LR methods and data mining techniques.

• Advances in materials Research
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• v.5 no.4
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• pp.263-277
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• 2016

Mechanical properties of $Al/Al_2O_3$ and $Al/B_4C$ composites prepared through powder metallurgy are estimated up to 50% $Al_2O_3$ and 35% $B_4C$ weight fractions using micromechanics models and experiments. The experimental Young's modulus up to 0.40 weight fraction of ceramic is found to lie closely between Ravichandran's/Hashin-Shtrikman lower/upper bounds, and close to self consistent method/Miller and Lannutti method/modified rule of mixture/fuzzy logic method single value predictions. Measured Poisson's ratio lies between rule of mixture/Ravichandran lower and upper bound/modified Ravichandran upper bounds. Experimental Charpy energy lies between Hopkin-chamis method/equivalent charpy energy/Ravichandran lower limit up to 20%, and close to the reciprocal rule of mixture for higher $Al_2O_3$ content. Rockwell hardness (RB) and Micro-hardness of $Al/Al_2O_3$ are closer to modified rule of mixture predictions.