• Journal of Genetic Medicine
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• v.16 no.1
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• pp.15-18
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• 2019

SHORT syndrome is an extremely rare congenital condition due to a chromosomal mutation of the PIK3R1 gene found at 5q13.1. SHORT is a mnemonic representing six manifestations of the syndrome: (S) short stature, (H) hyperextensibility of joints and/or inguinal hernia, (O) ocular depression, (R) Rieger anomaly, and (T) teething delay. Other key aspects of this syndrome not found in the mnemonic include lipodystrophy, triangular face with dimpled chin (progeroid facies, commonly referred to as facial gestalt), hearing loss, vision loss, insulin resistance, and intrauterine growth restriction (IUGR). 3q duplication syndrome is rare syndrome that occurs due to a gain of function mutation found at 3q25.31-33 that presents with a wide array of manifestations including internal organ defects, genitourinary malformations, hand and foot deformities, and mental disability. We present a case of a 2 year and 3 month old male with SHORT syndrome and concurrent 3q duplication syndrome. The patient presented at birth with many of the common manifestations of SHORT syndrome such as bossing of frontal bone of skull, triangular shaped face, lipodystrophy, micrognathia, sunken eyes, and thin, wrinkled skin (progeroid appearance). Additionally, he presented with findings associated with 3q duplication syndrome such as cleft palate and cryptorchidism. Although there is no specific treatment for these conditions, pediatricians should focus on referring patients to various specialists in order to treat each individual manifestation.

• Steel and Composite Structures
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• v.47 no.3
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• pp.405-421
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• 2023

An experimental study on six axially-loaded composite short columns with different thicknesses of steel tube and that of the concrete plate was carried out. Compared to the mechanical behavior of component specimens under axially compressed, the failure modes, compression deformation, and strain process were obtained. The two main parameters that have a significant enhancement to cross-sectional strength were also analyzed. The failure of an axially loaded UHPC-CFST short column is due to the crushing of the UHPC plate, while the CFST member does reach its maximum resistance. A reduction coefficient K'c, related to the confinement coefficient, is introduced to account for the contribution of CFST members to the ultimate load-carrying capacity of the UHPC-CFST composite short columns. Based on the regression analysis of the relationship between the confinement index ξ and the value of fcc/fc, a unified formula for estimating the axial compressive strength of CFST short columns was proposed, combined with the experimental results in this research, and an equation for reliably predicting the strength of UHPC-CFST composite short columns under axial compression were also proposed.

• Korean Chemical Engineering Research
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• v.61 no.1
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• pp.26-31
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• 2023

For durability improvement of polymer electrolyte membrane fuel cell (PEMFC) polymer membrane, accelerated durability evaluation methods that can evaluate durability in a short time have been researched and developed. However, the lifespan of fuel cells for large commercial vehicles such as trucks and buses is more than three times that of passenger cars, and the chemical accelerated stress test (AST) time is also longer, reaching 1,500 hours or more. Therefore, in this study, as a method to evaluate the chemical durability of a membrane within a short time, it was examined whether the durability could be predicted by the pristine membrane characteristics. Hydrogen crossover current density (HCCD) and short resistance (SR) were estimated as initial characteristics, and AST time was predicted through the Fenton experiment, which was possible as an out-of-cell experiment for 3 hours. As the HCCD and fluoride ion emission concentration increased, the AST time tended to be linearly shortened, but there was a deviation (R² ≒0.65). When the SR decreased, the AST time showed a linear increase, and the accuracy was high (R² =0.93), so the AST time could be predicted with the initial SR of the membrane.

• Journal of Power Electronics
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• v.16 no.1
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• pp.362-373
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• 2016

The on-line measurement of high-power IGBT collector current is important for the hierarchical control and short-circuit and overcurrent protection of its driver and the sensorless control of the converter. The conventional on-line measurement methods for IGBT collector current are not suitable for engineering measurement due to their large-size, high-cost, low-efficiency sensors, current transformers or dividers, etc. Based on the gate driver, this paper has proposed a current measuring circuit for IGBT collector current. The circuit is used to conduct non-intervention on-line measurement of IGBT collector current by detecting the voltage drop of the IGBT power emitter and the auxiliary emitter terminals. A theoretical analysis verifies the feasibility of this circuit. The circuit adopts an operational amplifier for impedance isolation to prevent the measuring circuit from affecting the dynamic performance of the IGBT. Due to using the scheme for integration first and amplification afterwards, the difficult problem of achieving high accuracy in the transient-state and on-state measurement of the voltage between the terminals of IGBT power emitter and the auxiliary emitter (u_Ee) has been solved. This is impossible for a conventional detector. On this basis, the adoption of a two-stage operational amplifier can better meet the requirements of high bandwidth measurement under the conditions of a small signal with a large gain. Finally, various experiments have been carried out under the conditions of several typical loads (resistance-inductance load, resistance load and inductance load), different IGBT junction temperatures, soft short-circuits and hard short-circuits for the on-line measurement of IGBT collector current. This is aided by the capacitor voltage which is the integration result of the voltage uEe. The results show that the proposed method of measuring IGBT collector current is feasible and effective.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.4
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• pp.388-396
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• 2021

Antimicrobial resistance patterns of Escherichia coli were investigated. Strains were isolated from 310 shellfish, 36 crustaceans, and 12 fish collected off the West Coast of Korea from April 2019 to October 2020. Two hundred and ninety-five E. coli strains were isolated from shellfish, 100 from crustaceans, and 54 from fish. Strains isolated from shellfish showed the highest resistance to ampicillin (27.5%), whereas those from crustaceans were resistant to sulfisoxazole (30.0%) and those from fish were resistant to ampicillin (59.3%) and sulfisoxazole (59.3%). Ceftazidime resistance was observed in strains isolated from short neck and hard clams, whereas gentamicin resistance was observed in strains from fish. Multi-drug resistance was observed in 56 strains (48.7%) isolated from shellfish, 11 (28.2%) from crustaceans and 27 (73.0%) from fish. Depending on the source of isolation, the strains showed specific antimicrobial resistance tendency. Strains isolated from shellfish showed 12 different multi-drug resistance patterns, whereas those from crustaceans showed high resistance (59%) to a single antimicrobial agent and those from fish showed a broad trend of multi-drug resistance to more than eight antimicrobials.

• The Korean Journal of Zoology
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• v.9 no.1
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• pp.7-15
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• 1966

In a previous paper, the dirunal and monthly changes of the tidal flat temperature and chlorinity were observed. In this paper the resistance of the young short necked clam in various growth stages to the temperature, to the chlorinity and to the exposure were studies. The young clam used were in early (E), medium (M) and late (L) young stages whose shell lengths were 2.0-3.5mm, 9.0-11.0mm. and 14.0-16.0mm., respectively. The results were : 1. At various sea water temperatures , the chlorinity resistance of the young clam was directly proportional to the shell length. 2. When both inadequate sea water temperature and abnormal chlorinity are simultaneously applied, the resistance of these young clams was more markedly reduced than the case of applying either one of these conditions. 3. In clams of M and L, no lethal effect were observed when daily immersion of four to eight hours for a week into the sea water of any concentration of chloriity at 26-34$^{\circ}C$, whereas in E, 37-90% of mortalities were obtained by immersion of eight hours daily into both the fresh water and the sea water of higher chloriniites (more than 23.5$\textperthousand$ Cl) at the same temperature above. 4. The lower critical thermal maximum for lethal to the young clam was 38$^{\circ}C$. With four hours immersion daily at the water temperature of 38$^{\circ}C$, the mortalities of E, M and L to the lower chlorinities (less than 6.7$\textperthousand$Cl) were 100, 70-100 and 27-37% respectively ; to the higher chlorinities (more than 23.5$\textperthousand$Cl) 10-70, 10-37 and 3 % respectively ; to the normal range of chlorinities (13.4-16.8$\textperthousand$Cl) 0-13, 3 and 0 % respectively. 5. No lethal effects were observed in E and M clams immersed continuously for seven days in sea water with chlornities of 7.2 -21.7$\textperthousand$Cl at 18-24$^{\circ}C$, while notable mortalities were observed in E which had been kept at lower (less than 4.8$\textperthousand$ Cl) and higher (more than 24.1$\textperthousand$ Cl) chlorinites. 6. Although the resistance of the young clam to the chlorinity may have to be related closely to the life history of the clam prior subject to the experiment, the adapted chlorinity range was 7.2-19.3$\textperthousand$ Cl and the optimum range was 13.4-16.8$\textperthousand$Cl. 7. Remarkable lethal effects were observed for the E and M clams to the exposure temperature of 38$^{\circ}C$ whereas the L and had no such fatal results.

• The Journal of Pediatrics of Korean Medicine
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• v.32 no.2
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• pp.64-71
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• 2018

Objectives The purpose of this study is to examine the correlation of antibiotics administration duration and antimicrobial resistance by reviewing domestic and foreign literatures. Methods We searched literatures dated up to 23 February, 2018 in PubMed and Cochrane Library using terms of "Anti-Bacterial Agents", "Carrier State", "Nasopharynx", "Drug Administration Schedule", and also searched via RISS (Research Information Service System), KISS (Koreanstudies Information Service System), DBpia (DataBase Periodical Information Academic) using terms of antibiotics, resistance, and dose. Results In comparison with shortened and standard antibiotic course, longer treatment duration is associated with greater antimicrobial resistance or non-significant difference, but we cannot find literature that shortened antibiotic course increases antimicrobial resistance on human nasopharyngeal flora. Conclusions Currently, there is no evidence that completing the standard antibiotic course reduces antimicrobial resistance. It can be a strategy for reducing antibiotic use to apply Korean medicine treatment, as well as short-course antibiotic therapy or delayed antibiotic prescription. Additional well-designed trials should be conducted in domestic and foreign settings about the appropriate duration of antibiotic therapy.

• Journal of Welding and Joining
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• v.31 no.6
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• pp.27-31
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• 2013

Magnesium alloy is used on parts of aircraft and electronic equipment because of the highest specific strength among the common metal materials. Recently, studies about appling magnesium alloy sheet to automotive bodies are on the increase rapidly. For application to automotive bodies, researches about characteristics of resistance spot welding of magnesium alloy sheet are essential. Magnesium alloy has low boiling point, so getting sound bead shape is difficult when appling varies welding processes. Resistance spot welding is also particular about setting optimum welding conditions because of spatter generation, pores and cracks occurrence in nugget. And life of electrodes is very short because of alloying with copper that main material of electrodes. This requires frequent dressing and replacement of electrodes and decrease in productivity of resistance spot welding on magnesium alloy. Therefore in this study, for effective analysis of changes in tensile shear load and nugget size during electrode life test, evaluate detail characteristics of resistance spot welding on magnesium alloy sheet using dome type electrode.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.3
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• pp.246-251
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• 2013

Screen printing is commonly used to form the front/back electrodes in silicon solar cell. But it has caused high resistance and low aspect ratio, resulting in decreased conversion efficiency in solar cell. Recently the plating method has been combined with screen-printed c-Si solar cell to reduce the resistance and improve the aspect ratio. In this paper, we investigated the effect of light induced silver plating with screen-printed c-Si solar cells and compared their electrical properties. All wafers were textured, doped, and coated with anti-reflection layer. The metallization process was carried out with screen-printing, followed by co-fired. Then we performed light induced Ag plating by changing the plating time in the range of 20 sec~5min with/without external light. For comparison, we measured the light I-V characteristics and electrode width by optical microscope. During plating, silver ions fill the porous structure established in rapid silver particle sintering during co-firing step, which results in resistance decrease and efficiency improvement. The plating rate was increased in presence of light lamp, resulting in widening the electrode with and reducing the short-circuit current by shadowing loss. With the optimized plating condition, the conversion efficiency of solar cells was increased by 0.4% due to decreased series resistance. Finally we obtained the short-circuit current of 8.66 A, open-circuit voltage of 0.632 V, fill factor of 78.2%, and efficiency of 17.8% on a silicon solar cell.

• Steel and Composite Structures
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• v.39 no.4
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• pp.383-399
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• 2021

In the study, three 1:3-scale unequal span steel-concrete composite substructures with top-seat angle and double web angle connection were designed and identified as specimens GTSDWA-0.6, GTSDWA-1.0, and GTSDWA-1.4. Pseudo-static tests and refined numerical model analysis were conducted to examine the anti-progressive collapse performance of a semi-rigid steel-concrete composite substructure. The results indicated that the failure modes of the three specimens revealed that the fracture occurred in the root of the long leg of the top/seat angle in tension at the connection. With increases in the span ratio of the left and right composite beams, the bearing capacities of the composite substructures decreased, and the corresponding displacement increased. With respect to GTSDWA-0.6 and GTSDWA-1.4, the resistance due to the short composite beam corresponded to 62% and 60%, respectively, and the total resistance provided by the short composite beam exceeded that of the long composite beam. With respect to GTSDWA-1.0, the resistance due to the left and right composite beams was similar. All three specimens underwent the flexure mechanism and flexure-axial mixed mechanism stages. They resisted the external load mainly via the flexure mechanism. Moreover, the addition of stiffeners on both sides of the top and seat angles is advantageous in terms of improving the collapse resistance and ductility of unequal span composite substructures.