• Journal of Korean Neurosurgical Society
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• v.65 no.6
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• pp.779-789
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• 2022

Objective : To analyze the effects of the number and shape of fenestrations on the mechanical strength of pedicle screws and the effects of bone cement augmentation (BCA) on the pull-out strength (POS) of screws used in conventional BCA. Methods : For the control group, a conventional screw was defined as C1, a screw with cannulated end-holes was defined as C2, a C2 screw with six pinholes was defined as C3, and the control group type was set. Among the experimental screws, T1 was designed using symmetrically placed thru-hole type fenestrations with an elliptical shape, while T2 was designed with half-moon (HM)-shaped asymmetrical fenestrations. T3 and T4 were designed with single HM-shaped fenestrations covering three pitches and five pitches, respectively. T5 and T6 were designed with 0.6-mm and 1-mm wider fenestrations than T3. BCA was performed by injecting 3 mL of commercial bone cement in the screw, and mechanical strength and POS tests were performed according to ASTM F1717 and ASTM F543 standards. Synthetic bone (model #1522-505) made of polyurethane foam was used as a model of osteoporotic bone, and radiographic examinations were performed using computed tomography and fluoroscopy. Results : In the fatigue test, at 75% ultimate load, fractures occurred 7781 and 9189 times; at 50%, they occurred 36122 and 82067 times; and at 25%, no fractures occurred. The mean ultimate load for each screw type was 219.1±52.39 N for T1, 234.74±15.9 N for T2, 220.70±59.23 N for T3, 216.45±32.4 N for T4, 181.55±54.78 N for T5, and 216.47±29.25 N for T6. In comparison with C1, T1, T2, T3, T4, and T6 showed significantly different ultimate load values (p<0.05). However, when the values for C2 and the fenestrated screws were evaluated with an unpaired t test, the ultimate load value of C2 significantly differed only from that of T2 (p=0.025). The ultimate load value of C3 differed significantly from those of T1 and T2 (C3 vs. T1 : p=0.048; C3 vs. T2 : p<0.001). Linear correlation analysis revealed a significant correlation between the fenestration area and the volume of bone cement (Pearson's correlation coefficient r=0.288, p=0.036). The bone cement volume and ultimate load significantly correlated with each other in linear correlation analysis (r=0.403, p=0.003). Conclusion : Fenestration yielded a superior ultimate load in comparison with standard BCA using a conventional screw. In T2 screws with asymmetrical two-way fenestrations showed the maximal increase in ultimate load. The fenestrated screws can be expected to show a stable position for the formation of the cement mass.

• Journal of Korean Traditional Oncology
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• v.23 no.1
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• pp.33-43
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• 2018

Objectives: To observe the mitigating effects of a Traditional Korean Medicine(TKM) treatment program especially including pharmacopuncture, with Cyclophosphamide and doxorubicin chemotherapy on a both sides breast cancer patient. Methods: AA 74 year-old female patient diagnosed with both sides breast cancer (Right) pT1bpN0M0, (Left) pT1cpN1Mx was admitted to hospital of Dong-eui university in May of 2017. She received Cyclophosphamide and Doxorubicin from May $31^{st}$ to August $2^{nd}$, 2017 followed by TKM treatment consisting of herbal medicine, acupuncture, moxibustion and pharmacopuncture (Trionycis Carapax, Non-toxic Bee Venom, and Cultivated Wild Ginseng Extract) for a period of almost 4 months, from May $13^{th}$ to August $19^{th}$, 2017. Symptoms were evaluated by the grade of chief complaints refer to Common Terminology Criteria for Adverse Events (CTCAE) and Eastern Cooperative Oncology Group (ECOG). Results: TKM including pharmacopuncture alleviated chemotherapy-induced nausea, fatigue, joint pain, diarrhea, insomnia. Conclusions: This case study potentiates TKM with pharmacopuncture's significant efficacy in aiding breast cancer patients suffering from Cyclophosphamide plus Doxorubicin induced adverse effects. Further research should take place for clear understanding of the exact amount of dosage and safety. Moreover it must be accompanied by long-term follow up researches.

• Journal of Biomedical Engineering Research
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• v.19 no.5
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• pp.433-441
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• 1998

This study was performed to evaluate the effects of surface flaw on the fracture of all-ceramic materials. A feldspathic porce lain of VMK68, a cashable ceramic of IPS-Empress, and an alumina-glass composite of In-Ceram were used. Specimens were prepared as 12$\times$3$\times$1mm in dimensions, and a Vickers-produced indentation crack was made at the center of the tensile surface. Test specimens were immersed in dlstilled water and In oil, which were broken under a crosshead speed of 0.05 mm/min by 3-point bend test at 37$^{\circ}C$. The characteristic patterns of Vickers indentation and fracture surfaces were examined by an optical microscope and a scanning electron microscope. The fracture surfaces of the VMK68 and the IPS-Empress showed a median crack pattern at the fracture origin and indicated a tendency to cleavage hackle. The fracture surface of the alumina-glass composite, In-Ceram, showed a Palmqvist crack pattern at the fracture origin and indicated a tendency of toughening by the frictional Interlocking between the microstructurally rough fracture surfaces.

• Korean Journal of Exercise Nutrition
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• v.24 no.4
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• pp.15-23
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• 2020

[Purpose] Lactate is a principal energy substrate for the brain during exercise. A single bout of high-intensity interval exercise (HIIE) can increase the blood lactate level, brain lactate uptake, and executive function (EF). However, repeated HIIE can attenuate exercise-induced increases in lactate level and EF. The lactate levels in the brain and blood are reported to be correlated with exercise-enhanced EF. However, research is yet to explain the cause-and-effect relationship between lactate and EF. This study examined whether lactate consumption improves the attenuated exercise-enhanced EF caused by repeated HIIE. [Methods] Eleven healthy men performed two sets of HIIE, and after each set, 30 min were given for rest and examination. In the 2^nd set, the subjects consumed experimental beverages containing (n = 6) and not containing (n = 5) lactate. Blood, cardiovascular, and psychological variables were measured, and EF was evaluated by the computerized color-word Stroop test. [Results] The lactate group had a higher EF (P < 0.05) and tended to have a higher blood lactate level (P = 0.082) than the control group in the 2^nd set of HIIE. Moreover, blood lactate concentration was correlated with the interference score (i.e., reverse score of EF) (r = -0.394; P < 0.05). [Conclusion] Our results suggest that the attenuated exercise-enhanced EF after repeated HIIE can be improved through lactate consumption. However, the role of lactate needs to be elucidated in future studies, as it can be used for improving athletes' performance and also in cognitive decline-related clinical studies.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.2
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• pp.156-163
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• 2009

Statement of problem: Recently, there have been increased esthetic needs for posterior dental restorations. The failure of posterior dental ceramic restoration are possible not only by the characters of the component materials but also by the type of food. Purpose: The research aim was to compare the in vitro fracture resistance of simulated first molar crowns fabricated using 4 dental ceramic systems, full-porcelain-occlusal-surfaced PFG, half-porcelain-occlusal-surfaced PFG, Empress 2, Ice Zirkon and selected Korean foods. Material and methods: Eighty axisymmetric crowns of each system were fabricated to fit a preparation with 1.5- to 2.0-mm occlusal reduction. The center of the occlusal surface on each of 15 specimens per ceramic system was axially loaded to fracture in a Instron 4465, and the maximum load(N) was recorded. Afterwards, selected Korean foods specimens(boiled crab, boiled chicken with bone, boiled beef rib, dried squid, dried anchovy, round candy, walnut shell) were prepared. 15 specimens per each food were placed under the Instron and the maximum fracture loads for them were recorded. The 95% confidence intervals of the characteristic failure load were compared between dental ceramic systems and Korean foods. Afterwards, on the basis of previous results, 14Hz cyclic load was applied on the 4 systems of dental ceramic restorations in MTS. The reults were analyzed by analysis of variance and Post Hoc tests. Results: 95% confidence intervals for mean of fracture load 1. full porcelain occlusal surfaced PFG Crown: 2599.3 to 2809.1 N 2. half porcelain occlusal surfaced PFG Crown: 3689.4 to 3819.8 N 3. Ice Zirkon Crown: 1501.2 to 1867.9 N 4. Empress 2 Crown: 803.2 to 1188.5 N 5. boiled crab: 294.1 to 367.9 N 6. boiled chicken with bone: 357.1 to 408.6 N 7. boiled beef rib: 4077.7 to 4356.0 N 8. dried squid: 147.5 to 190.5 N 9. dried anchovy: 35.6 to 46.5 N 10. round candy: 1900.5 to 2615.8 N 11. walnut shell: 85.7 to 373.1 N under cyclic load(14Hz) in MTS, fracture load and masticatory cycles are: 1. full porcelain occlusal surfaced PFG Crown fractured at 95% confidence intervals of 4796.8-9321.2 cycles under 2224.8 N(round candy)load, no fracture under smaller loads. 2. half porcelain occlusal surfaced PFG Crown fractured at 95% confidence intervals of 881705.1-1143565.7 cycles under 2224.8 N(round candy). no fracture under smaller loads. 3. Ice Zirkon Crown fractured at 95% confidence intervlas of 979993.0-1145773.4 cycles under 382.9 N(boiled chicken with bone). no fracture under smaller loads. 4. Empress 2 Crown fractured at 95% confidence intervals of 564.1-954.7 cycles under 382.9 N(boiled chicken with bone). no fracture under smaller loads. Conclusion: There was a significant difference in fracture resistance between experimental groups. Under single load, Korean foods than can cause fracture to the dental ceramic restorations are boiled beef rib and round candy. Even if there is no fracture under single load, cyclic dynamic load can fracture dental posterior ceramic crowns. Experimental data with 14 Hz dynamic cyclic load are obtained as follows. 1. PFG crown(full porcelain occlusion) was failed after mean 0.03 years under fracture load for round candy(2224.8 N). 2. PFG crown(half porcelain occlusion) was failed after mean 4.1 years under fracture load for round candy(2224.8 N). 3. Ice Zirkon crown was failed after mean 4.3 years under fracture load for boiled chicken with bone(382.9 N). 4. Empress 2 crown was failed after mean 0.003 years under fracture load for boiled chicken with bone(382.9 N).

• Journal of Society of Preventive Korean Medicine
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• v.19 no.3
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• pp.11-19
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• 2015

Objective : This study aimed to develop and preliminary validate the Mibyeong Questionnaire (MQ) based on Deficiency-Stagnation pattern, which was report of a person's health condition that comes directly from the person. Method : The first phage of developing a MQ was to generate and exhaustive list of all MQ issue that are relevant to the domain of interest, using literature research and expert group discussions. Through those steps, we established MQ with 33 items divided into two parts: 21-item deficiency pattern and 12-item stagnation pattern. The second phage, we examined the preliminary tests of reliability and validity including the 16-item Deficiency of MQ (16D-MQ), with data (n=1,890) already collected on the Korean medicine data center in KIOM. Results : Exploratory factor analysis revealed three factors of the 16D-MQ. These factors were fatigue(Qi, 氣); psychic and physical elements(Shen, 神); and skin and hair(Jing, 精). Cronbach's coefficient alpha was 0.876 and the intraclass correlation coefficients was 0.368-0.538. In support of criteria validity, the 16D-MQ was weakly correlated with EQ-5D and physicians's opinion, but it was acceptable. Conclusion : The MQ shows that it has an appropriate level of internal consistency and validity. We think further study to reveal its reliability and validity, including stagnation pattern as well as deficiency pattern, is needed.

• Journal of Society of Preventive Korean Medicine
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• v.20 no.3
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• pp.45-53
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• 2016

Objectives : The number of people in Mibyeong state that complain of physical and mental discomfort but without a clear medical diagnosis has rapidly increased, but the conventional medical system is insufficient to care for these people. By establishing an evaluation instrument for Mibyeong state, it will be possible to provide a research base for Mibyeong management system and expand the clinical area of integrative medicine. Methods : Mibyeong Index was designed to measure inconvenience and resilience of subject's complains including four physical symptoms (fatigue, pain, low sleep quality, indigestion) and mental distress include anxiety, anger, depression. A 21-item quality of healthy measure was developed and tested. We used results of a nation-wide stratified sampled adult data in Korea. Results and Conclusions : Mibyeong index had adequate internal consistency, Cronbach's alpha was 0.88 in general population(N=1,110). The correlation between establised quality of life questionnaires (including SF-12 and EQ-D5 VAS) and the Mibyeong index were from 0.468 to 0.493. The national promotion of advanced health for an aging society and original Mibyeong care technology based on traditional Korean medicine can be developed by a self-care system that enhancing health before suffering illness. We expect that this instrument could be contribute to health management of people in Mibyeong state.

• Journal of Power System Engineering
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• v.13 no.5
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• pp.52-58
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• 2009

A gas turbine consists of an upstream compressor and a downstream turbine with a combustion chamber, and also the compressor and the turbine are generally coupled using a single shaft. Many casing bolts are used to assemble two horizontally separated casings, the gas turbine casing and the compressor casing, in both of axial and vertical directions. Because drilled holes for casing bolts in vertical direction are often too close to drilled holes for casing bolts in axial direction, one can observe cracks in the area frequently during operations of a gas turbine. In this study of the root cause analysis for the cracking initiating from the drilled holes of the casings of a gas turbine, the finite element analysis(FEA) was applied to evaluate the thermal and mechanical characteristics of the casings. By applying the field operation data recorded from combined cycle power plants for FEA, thermal and thermo-mechanical characteristics of a gas turbine are analyzed. The crack is initiated at the geometrical weak point, but it is found that the maximum stress is relieved when the same type of cracks is introduced on purpose during FEA. So, it is verified that the local fracture could be delayed by machining the same type of defects near the hole for casing flange bolts of the gas turbine, where the crack is initiated.

• Journal of Ocean Engineering and Technology
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• v.33 no.5
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• pp.435-446
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• 2019

Because offshore structures are affected by various environmental loads, the risk of damage is high. As a result of ever-changing ocean environmental loads, damage to offshore structures is expected to differ from year to year. However, in previous studies, it was assumed that a relatively short period of load acts repeatedly during the design life of a structure. In this study, the residual life of an offshore wind turbine support structure was evaluated in consideration of the timing uncertainty of the ocean environmental load. Sampling points for the wind velocity, wave height, and wave period were generated using a central composites design, and a transfer function was constructed from the numerical analysis results. A simulation was performed using the joint probability model of ocean environmental loads. The stress time history was calculated by entering the load samples generated by the simulation into the transfer function. The damage to the structure was calculated using the rain-flow counting method, Goodman equation, Miner's rule, and S-N curve. The results confirmed that the wind speed generated at a specific time could not represent the wind speed that could occur during the design life of the structure.

• Journal of Korean Public Health Nursing
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• v.16 no.1
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• pp.176-189
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• 2002

The purpose of this study were to illustrate the various medication error types and causes and identified to related drugs to provide basic data for preventing nurses' medication error by analysing 73 cases of AJN 'medication Error' column(1993, Oct -2000, Nov). Nurses' types of medication error were classified into 7 types. The most frequent error types are wrong medication$(21.9\%)$ and the wrong dose$(21.9\%)$ together. The others are wrong $time(4.1\%)$, $omission(2.7\%)$, mechanical $error(2.7\%)$, incorrect IV $rate(1.4\%)$. wrong route $administration(1.4\%)$ in order. Nurses' causes of medication error were 9 kinds. The most frequent type is confusing between similar drug shape, color, size, name, injection devices and patient's $name(43.9\%)$ and the others are lack of knowledge about $drugs(26.8\%),\; slips(7.3\%),\; miscalculating\;dose(4.9\%)$, incorrect adjusts $devices(4.9\%)$, difficulty to read or illegible decimal $point(4.9\%),$ $abbreviation(2.4\%)$, fatigue with $overwork(2.4\%)$ and no communication with $patient(2.4\%)$ in order. Related drugs with medication error are as follows. - dose unit(IU. minims. mcg/min. mEq) : Heparin. insulin. synthetic calcitonin, some enzymes and hormones, vitamins, some antibiotics, tuberculin injection. MgSO4 injection. nitroglycerin - similar size, color and shape drug : $0.9\%$ N/S and acetic acid $0.25\%$ for irrigation. premixed 2mg lidocaine sol. and $0.9\%$ N/S, gentamycin 20mg/2mL for children and 80mg/2mL for adult, dextroamphetamine 5mg and 10mg capsule. sedatives chloral hydrate 250mg/5mL and 500mg/5mL - similar name :Aredia(pamidronate disodium) and Adriamycin(doxorubicin), Lamictal (lamotrigine) and Lamisil 250mg. Elderpryl and enalapril, cefotaxime and cefoxitin, carboplatin and cisplatin, sumatriptan and zolmitriptan, Celebrex and Celexa, Humulin and Humalog, Percodan and Percocet, Diabeta and Diabinese, Epivir and Retrovir, Xanax(alprazolam) and Zantac(ranitidine) - decimal point : low molecular weight warfarin, methotrexate - unfamiliar drug uses of familiar drug ; methotrexate. droperidol, imipramine, propranolol - number of drug name(misleading chemical name) : 6-thioguanine, 6-mercaptopurine, 5-fluorouracil - type of administration route : Oxycodone(OxyContin). - administration time : acarbose(Precose). - injection way (Z-track method): hydroxyzine - epidural cathether : LMWHs(enoxaparin, dalteparin), - ADD Vantage self contained delivery system : ceftriaxone(Rocephin)