• Title/Summary/Keyword: Punch test

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Punching Fracture Simulations of Circular Unstiffened Steel Plates using Three-dimensional Fracture Surface (3차원 파단 변형률 평면을 이용한 비보강 원판의 펀칭 파단 시뮬레이션)

  • Park, Sung-Ju;Lee, Kangsu;Choung, Joonmo
    • Journal of Ocean Engineering and Technology
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    • v.30 no.6
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    • pp.474-483
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    • 2016
  • Accidental events such as collisions, groundings, and hydrocarbon explosions in marine structures can cause catastrophic damage. Thus, it is extremely important to predict the extent of such damage, which determines the total amount of oil spills and the residual hull girder strength. Punching fracture tests were conducted by Choung (2009b), where various sizes of indenters and circular unstiffened steel plates with different thicknesses were used to quasi-statically realize damage extents. A three-dimensional fracture strain surface was developed based on a reference (Choung et al., 2015b), where the average stress triaxiality and average normalized Lode angle were used as the parameters governing the fracture of ductile steels. In this study, new numerical analyses were performed using very fine axisymmetric elements in combination with an Abaqus user-subroutine to implement the three-dimensional fracture strain surface. Conventional numerical analyses were also conducted for the tests to identify the best fit fracture strain values by changing the fracture strains. Based on the phenomenon of the average normalized Lode angle starting out positive and then becoming slightly negative, it was inferred that the shear stress primarily dominates in determining the fractures locations, with a partial contribution from the compressive stress. It should be stated that the three-dimensional fracture surface effectively predicted at least the shear stress-dominant fracture behavior of a mild steel.

4 Cases of Traditional Korean Medicine Treatment for Patients with Surgical Margin Positive after LEEP in Cervical Intraepithelial Neoplasia (LEEP시술 절단면에 병변이 잔존하는 자궁경부상피내종양(CIN) 한의학적 치험 4례)

  • Lee, Eun;Lee, Kyung-yeob;Yu, Byung-kook
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.34 no.3
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    • pp.149-158
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    • 2020
  • The positive margins after LEEP(loop electrosurgical excision procedure) in cervical intraepithelial neoplasia are generally considered to be a risk factor for the recurrence or persistence of CIN currently. When positive margin exists, secondary LEEP or hysterectomy is performed. The aim of this study was to observe effects of Traditional Korean Medicine treatment for patients with surgical margin positive after LEEP. It was conducted retrospective chart review for 4 patients with the surgical margin positive after LEEP, who were scheduled to have secondary LEEP 3 months later. Patients were treated with herbal medicine, pharmacopuncture and herbal liquid vaginal treatment. They were followed up by cytology, colposcopy, human papillomavirus DNA test and punch-biopsy at 1, 3 and 6 months. After 3 month of treatment, three patients did not need secondary LEEP because of normal cytology, negative HPV status and normal colposcopy, while the other patient underwent secondary LEEP because of ASCUS cytology and positive high-risk HPV. After 6 month of treatment, the other patient also had normal cytology, negative HPV status and normal colposcopy and had been in fifth week of pregnancy. This study suggest that Traditional Korean Medicine treatment may be an effective to the patients with surgical margin positive after LEEP in cervical intraepithelial neoplasia.

Evaluation of the wound healing ability of an Abeliophyllum distichum Nakai extract in ICR mouse and of antibacterial activity against human cutaneous flora

  • Go, Young Bin;Lee, Ji Hwan;Oh, Han Jin;Kim, Yong Ju;An, Jae Woo;Chang, Se Yeon;Song, Dong Cheol;Cho, Hyun Ah;Cho, Jin Ho
    • Korean Journal of Agricultural Science
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    • v.48 no.3
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    • pp.567-574
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    • 2021
  • In this study, we evaluated the wound healing rate and, inflammatory cells effects of by Abeliophyllum distichum Nakai (ADN) extract in mice. We also assessed the stability of the ADN extract upon exposure to sunlight. Treatments were as follows: 1) CON (only saline solution), T1 (CON + 0.0125% ADN extract), T2 (CON + 0.05% ADN extract), and T3 (CON + 0.5% ADN extract). A 4 mm punch was used in the central part of the dorsal area to separate it from the subcutaneous tissue, causing a full-thickness skin wound. An amount of 1 mL of each sample was sprayed onto the treatment section of the wound with a pipette every day from the day of wound creation, with proper application ensured using brush. In the stability test, the pH was measured at 1, 4, and 8 weeks after exposing the samples of each treatment section to sunlight considering, the higher concentrations of the ADN extract. The results of this study indicate that the effectiveness of the wound contraction rate in the mice to which the ADN extract was applied was low. Moreover, the stability of the sample containing a high concentration of the ADN extract could not be verified. In addition, no significant results were obtained in the inflammatory reaction assessment. Therefore, additional research focusing on wound contraction, stability, and inflammatory cell outcomes of the ADN extract is needed.

Quantitative Evaluation of Wear Resistance of Stamping Tool with Respect to Hardness of Tool Materials in Cold Stamping of TRIP1180 Steel Sheets (TRIP1180 판재의 냉간 스탬핑공정에서 금형강의 경도 특성에 따른 내마모성 평가)

  • Bang, J.H.;Bae, G.;Song, J.H.;Kim, H.G.;Lee, M.G.
    • Transactions of Materials Processing
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    • v.31 no.3
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    • pp.129-135
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    • 2022
  • The purpose of this study was to quantitatively evaluate the influence of hardness of tool materials on wear resistance in the sheet metal forming process. Punches used in the wear test were made of STD-11 and K340 tool material, and the tempering temperature was set to 530℃ and 500℃, respectively, to control the hardness of the tool materials. The punches mimic the shape of stamping tool of automotive body component to reflect its plastic deformation, and are designed to concentrate wear on the curvature region of punches. Progressive die and coil sheet were used to save time, cost, and raw sheet materials. By quantitatively measuring the wear depth of the punches, the wear behavior and mechanism of the punches were investigated, and characteristics of hardness and wear resistance according to tool materials and tempering temperatures were evaluated. Testing results indicate that the punch made of K340 tool steel with higher hardness had better wear resistance than that of STD-11 tool steel, and the hardness and wear resistance of tool steel were significantly impacted by the tempering temperature.

Cutaneous Xanthoma in a Dog

  • Yeonhoo Jung;Moonseok Jang;Rahye Kang;Wanghui Lee;Seongjun Park
    • Journal of Veterinary Clinics
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    • v.40 no.5
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    • pp.382-386
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    • 2023
  • A 2-year-old, 12.5 kg, castrated male, mixed-breed dog was presented with a 1-year history of pruritus and progressive alopecia. On physical examination, no remarkable findings were detected including body condition score (5/9). A dermatological examination of the dog revealed generalized erythema, papules or plaques, especially on the face, auricle, dorsum, and shoulder. A fine-needle aspiration of the dorsum and face lesions revealed various numbers of macrophages with foamy cytoplasm and multinucleated giant cells. A bacterial culture test showed the growth of Staphylococcus pseudintermedius. A complete blood cell count was unremarkable and biochemical abnormalities included hyperglobulinemia (4.8 g/dL, reference interval 2.5-4.5 g/dL), mild hypertriglyceridemia (277 mg/dL, reference interval 10-100 mg/dL) and mild hypercholesterolemia (383 mg/dL, reference interval 110-320 mg/dL). Additional diagnostic tests were performed to identify the underlying cause of hyperlipidemia. Canine pancreatic lipase immunoreactivity (<50 ng/mL, reference interval 0-200 ng/mL) and total T4 (1.4 ㎍/dL, reference interval 1.1-5.6 ㎍/dL) were within the reference intervals. For a definitive diagnosis, skin biopsy specimen was collected from the papular lesions on the dorsum by using a 4 mm biopsy punch. A histopathological examination revealed numerous large macrophages with abundant foamy cytoplasm in the dermis. The foamy macrophages were located diffusely between the collagen fibers. Extracellular amorphous lipid deposits were also presented in the dermal tissue. A definitive diagnosis of cutaneous xanthoma was made based on clinical signs and cytological and histopathological results.

Optimum Rheological Mixed ratio of Jumbo Squid and Alaska Pollock Surimi for Gel Product Process (대형오징어와 명태혼합 어묵의 가열겔화시 물성에 영향을 미치는 최적 혼합비)

  • LEE Nahm-Gull;YOO Seung-Geun;CHO Young-Je
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.6
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    • pp.718-724
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    • 1999
  • This study was investigated the changes of the properties of matter such as the gel formation of the combined fish based on the mixed rate between the ocean jumbo squid and Alaska pollock surimi, and compared the relationships between the gel formation and water holding capacity. The changes of the gel formation based on 20 min fish grinding time and $2.5\%$ salt concentration according to the mixed rate was thought as the optimal addition limit. There was no significant function of gel product more than $20\%$ Jumbo squid meat. The more squid meat in the mixed meat could make the lower breaking stress but 7:3 rate of pollock : squid could retain breaking strain. The effect of the moisture content on mixed fish meat was studied and the drastic decrease of the gel formation and water holding capacity was indicated in $78\%$.

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A Study on the Effects of Empowerment Perception Level on Job Satisfaction of Hairdresser (헤어 미용사들의 지각된 임파워먼트가 직무만족에 미치는 영향)

  • Jeon, Seon-Bok
    • Journal of Digital Convergence
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    • v.15 no.4
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    • pp.537-547
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    • 2017
  • This study attempted to determine differences between the perceived empowerment level and job satisfaction depending on hairdressers' demographic characteristics and analyze the effects of their empowerment on job satisfaction. For this, a total of 310 hairdressers in Gwangju-Jeonnam and Seoul-Gyeonggi-do were chosen through convenience sampling, and then a questionnaire survey was conducted. The valid 277 copies were used for final analysis. For data analysis, descriptive statistics, factor analysis, reliability analysis, t-test, ANOVA, Duncan's test, and multiple regression analysis were conducted using SPSS 15.0. The study results found the following: First, in terms of the subordinate factors of empowerment, the following four factors were found: meaningfulness, self-determination, competence, and impact. Second, depending on demographic characteristics (e.g., age, career, type of beauty salon, job title, punch-in time, monthly pay), a statistically significant difference was found between empowerment and job satisfaction (p<.01). Third, hairdressers' perceived empowerment level had a positive impact on job satisfaction (p<.01). In terms of the empowerment on job satisfaction by sub-factor, 'self-determination' was largest, followed by 'meaningfulness' and 'competence.' Therefore, beauty salon owners need to manage their business more efficiently by converging cosmetology and business management by expanding empowerment among hairdressers properly after recognizing the importance of hairdresser empowerment.

Enhanced Dissolution and Permeation of Biphenyl Dimethyl Dicarboxylate Using Solid Dispersions (고체분산체로부터 비페닐디메칠디카르복실레이트의 용출 및 투과 증전)

  • Moon, Jee-Hyun;Chun, In-Koo
    • Journal of Pharmaceutical Investigation
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    • v.29 no.3
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    • pp.227-234
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    • 1999
  • Solid dispersions were prepared to increase the dissolution rate of biphenyl dimethyl dicarboxylate (DDB) using water-soluble carriers such as povidone, copolyvidone, $2-hydroxypropyl-{\beta}-cyclodextrin (HPCD)$, sodium salicylate or sodium benzoate by solvent evaporation method. Solid dispersions were characterized by infrared spectrometry, differential scanning calorimetry (DSC) and powder X-ray diffractometry, dissolution and permeation studies. DDB tablets (7.5 mg) were prepared by compressing the powder mixtures composed of solid dispersions, lactose, com starch, crospovidone and magnesium stearate using a single-punch press. DDB capsules (7.5 mg) were also prepared by filling the mixtures in empty hard gelatin capsules (size No.1). From the DSC and powder x-ray diffractometric studies, it was found that DDB was amorphous in the HPCD or copolyvidone solid dispersions. Dissolution rates after 10 min of DDB alone and solid dispersions (1 : 10) in sodium benzoate, sodium salicylate and copolyvidone were 11.8, 23.5, 22.8 and 82.5%, respectively. Dissolution rates of DDB after 30 min from 1 : 10 and 1 : 20 copolyvidone solid dispersions were 80.5 and 95.0%, respectively. For the DDB tablets prepared using solid dispersions (1 : 20), the initial dissolution rate was dependent on carrier material, and was ranked in order, $Kollidon\;30\;{\ll}$ copolyvidone < HPCD. For the HPCD solid dispersion tablets, dissolution rate reached 97.4% after 15 min, but thereafter slowly decreased to 80.7% after 2 hr due to the precipitation of DDB. However, in the case of copolyvidone solid dispersion tablets, dissolution increased linearly and reached 93.4% after 2 hr. Reducing the volume of test medium from 900 to 300 ml markedly decreased the dissolution rate of the tablets containing 1 : 20 HPCD solid dispersions and 1 : 10 copolyvidone solid dispersion. For 1 : 20 copolyvidone solid dispersion tablets, there was no significant change in dissolution rate up to 1 hr with different volumes of test medium. Preparation of the copolyvidone solid dispersion (1 : 20) in capsules markedly delayed the dissolution (31.2 % after 2hr) due to the limited diffusion within capsules. The permeation rate $(13.4\;g/cm^2\;after\;8\;hr)$ of DDB through rabbit duodenal mucosa from copolyvidone solid dispersion (1 : 10) was markedly enhanced, when compared with drug alone or physical mixtures. From overall findings, DDB formulations containing copolyvidone solid dispersions (1 : 20) could be used to remarkably improve the dissolution rate in dosage form of powders and tablets.

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Cervicography as a Screening Test for Cervical Cancer (자궁경부암 선별 검사에서 자궁경부 확대 촬영술의 이용)

  • Lee, Doo-Jin;Lee, Sung-Ho
    • Journal of Yeungnam Medical Science
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    • v.16 no.2
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    • pp.169-180
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    • 1999
  • Background: Uterine cervical cancer is the most common malignant tumor of the women in Korea. This study was undertaken to evaluate the usefulness of the cervicography as a screening test of cervical cancer. Materials and Methods: Cervicography was taken from 482 women at department of obstetrics and gynecology, at Yeungnam University Hospital from March 1, 1998 to October 31, 1999. Of the 482 women, 172 women were exc1uded from the study for various reasons, and 310 women completed the study. Three-hundred and ten women had cervical cytology (Papanicolaou smear), cervicography and colposcopy, and punch biopsy was undertaken if any of the test result was abnormal. Results: The most common age group was 35-39, and 40-44, 45-49 in order and most common reason for having a screening test was regular check for cervical cancer. The mean duration from the last Pap smear was 17.1 months, and 64 women(20.4%) never had any prior screening tests. Of the 310 women, 254 women were categorized as normal or having benign disease such as cervicitis, erosion or metaplasia. Biopsy was taken from 56 patients and the results were 26 chronic cervicitis, 4 mild dysplasia, 6 moderate dysplasia, 2 severe dysplasia, 14 carcinoma in situ and 4 invasive carcinoma. The results of cytology and cervicography were well correlated(p<0.05). The sensitivity and specificity of cytology were 86.7% and 76.9%, respectively and the sensitivity and specificity of cervicography were 56.7% and 96.2%, respectively. False negative rate of cervicography(43.3%) was much higher than those of cytology(13. 3%) (p<0.05), but false positive rate of cervicography(3.8%) was much lower than that of cytology(23.1%) (p<0.05). Conclusion: It seems inappropriate to use cervicography as a single screening test for cervival cancer, but it may be an effective complementary test for cytology to lower the false negative rate of cytology.

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Improvement of Dissolution rate of Felodipine Using Solid Dispersion and its Sustained Release Oral Dosage Form (고체분산체에 의한 펠로디핀의 용출율 개선과 서방성 경구제제)

  • Gil, Young-Sig;Hong, Seok-Cheon;Yu, Chang-Hun;Shin, Hyun-Jong;Kim, Jong-Sung
    • Journal of Pharmaceutical Investigation
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    • v.32 no.3
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    • pp.185-190
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    • 2002
  • To improve the solubility of poorly water-soluble drug and to develop a sustained release tablets, the need for the technique, the formation of solid dispersion with polymeric materials that can potentially enhance the dissolution rate and extent of drug absorption was considered in this study. The 1:1, 1:4, and 1:5 solid dispersions were prepared by spray drying method using PVP K30, ethanol and methylene chloride. The dissolution test was carried out at in phosphate buffer solution at $37^{\circ}C$ in 100 rpm. Solid dispersed drugs were examined using differential scanning calorimetry and scanning electron microscopy, wherein it was found that felodipine is amorphous in the PVP K30 solid dispersion. Felodifine SR tablets were prepared by direct compressing the powder mixture composed of solid dispersed felodipine, lactose, Eudragit and magnesium stearate using a single punch press. In order to develop a sustained-release preparation containing solid dispersed felodipine, a comparative dissolution study was done using commercially existing product as control. The dissolution rate of intact felodipine, solid dispersed felodipine and its physical mixture, respectively, were compared by the dissolution rates for 30 minutes. The dissolution rates of felodipine for 30 minutes from 1:1, 1:4, 1:5 PVP K30 solid dispersion were 70%, 78% and 90%. However, dissolution rate offelodipine from the physical mixture was 5% of drug for 30 minutes. Our developed product Felodipine SR Tablet showed dissolution of 17%, 50% and 89% for 1, 4, and 7 hours. This designed oral delivery system is easy to manufacture, and drug releases behavior is highly reproducible and offers advantages over the existing commercial product. The dissolution rate of felodipine was significantly enhanced, following the formation of solid dispersion. The solid dispersion technique with water-soluble polymer could be used to develop a solid dispersed felodipine SR tablet.