농가 근로환경 개선기획 ② - 우리목장 외국인 근로자 고용, 이것만은 알아두자.

황유진,Hwang, Yu-Jin 한국낙농육우협회 2016 낙농·육우 Vol.36 No.12

Atmospheric plasma spray 공정으로 제조된 Y₂O₃ 코팅층의 미세조직 및 기계적 특성에 미치는 분사 각도의 영향

황유진,김경욱,이호영,권식철,이기안,Hwang, Yu-Jin,Kim, Kyoung-Wook,Lee, Ho-Young,Kwon, Sik-Chol,Lee, Kee Ahn 한국분말재료학회 (*구 분말야금학회) 2021 한국분말재료학회지 (KPMI) Vol.28 No.4

The effects of different spray angles (90°, 85°, 80°) on the microstructure and mechanical properties of a Y₂O₃ coating layer prepared using the atmospheric plasma spray (APS) process were studied. The powders employed in this study had a spherical shape and included a cubic Y₂O₃ phase. The APS coating layer exhibited the same phase as the powders. Thickness values of the coating layers were 90°: 203.7 ± 8.5 ㎛, 85°: 196.4 ± 9.6 ㎛, and 80°: 208.8 ± 10.2 ㎛, and it was confirmed that the effect of the spray angle on the thickness was insignificant. The porosities were measured as 90°: 3.9 ± 0.85%, 85°: 11.4 ± 2.3%, and 80°: 12.7 ± 0.5%, and the surface roughness values were 90°: 5.9 ± 0.3 ㎛, 85°: 8.5 ± 1.1 ㎛, and 80°: 8.5 ± 0.4 ㎛. As the spray angle decreased, the porosity increased, but the surface roughness did not show a significant difference. Vickers hardness measurements revealed values of 90°: 369.2 ± 22.3, 85°: 315.8 ± 31.4, and 80°: 267.1 ± 45.1 HV. It was found that under the condition of a 90° angle with the lowest porosity exhibited the best hardness value. Based on the aforementioned results, an improved method for the APS Y₂O₃ coating layer was also discussed.

Laser powder bed fusion 공정으로 제조된 오스테나이트계 316L 스테인레스 강의 고온 산화 거동

황유진,위동열,김규식,이기안,Hwang, Yu-Jin,Wi, Dong-Yeol,Kim, Kyu-Sik,Lee, Kee-Ahn 한국분말재료학회 (*구 분말야금학회) 2021 한국분말재료학회지 (KPMI) Vol.28 No.2

In this study, the high-temperature oxidation properties of austenitic 316L stainless steel manufactured by laser powder bed fusion (LPBF) is investigated and compared with conventional 316L manufactured by hot rolling (HR). The initial microstructure of LPBF-SS316L exhibits a molten pool ~100 ㎛ in size and grains grown along the building direction. Isotropic grains (~35 ㎛) are detected in the HR-SS316L. In high-temperature oxidation tests performed at 700℃ and 900℃, LPBF-SS316L demonstrates slightly superior high-temperature oxidation resistance compared to HR-SS316L. After the initial oxidation at 700℃, shown as an increase in weight, almost no further oxidation is observed for both materials. At 900℃, the oxidation weight displays a parabolic trend and both materials exhibit similar behavior. However, at 1100℃, LPBF-SS316L oxidizes in a parabolic manner, but HR-SS316L shows a breakaway oxidation behavior. The oxide layers of LPBF-SS316L and HR-SS316L are mainly composed of Cr₂O₃, Fe-based oxides, and spinel phases. In LPBF-SS316L, a uniform Cr depletion region is observed, whereas a Cr depletion region appears at the grain boundary in HR-SS316L. It is evident from the results that the microstructure and the high-temperature oxidation characteristics and behavior are related.

봉독약침 후 발생한 Anaphylaxis 에 관한 임상적 연구

황유진,이병철,Hwang, Yoo-Jin,Lee, Byung-Chul 대한침구의학회 2000 대한침구의학회지 Vol.17 No.4

Bee-venom Acupucture has good effect on pain control but We may be anxious about the problem of side-effect. Bee-venom components are composed of phospholipase $A_2$, hyaluronidase, melitin, apamin, MCD peptide, citrate and so on. Especially Apamin, MCD peptide and histamine cause severe reacting that is named Anaphylaxis. Anaphylaxis is a clinical syndrome characterized by the acute system reaction of multiple organ systems to an IgE-mediated immunologic mediator release in previously sensitized individuals. Respiratory and dermatologic manifestations are the most commonly expressed clinical features of anaphylaxis, and a majority of anaphylactic reactions initially appear to be localized to these two systems. Anaphylatic reaction of bee-venom are expressed clinically ulticaria, itching sensation, erythema, dizziness, nausea, hypotension and so on. Especially ulticaria and erythema are end points of increased vascular permeability and vasodilatation at the other extreme of the clinical spectrum, Gastrointestinal mucosal edema and smooth muscle contraction can result in cramping abdominal pain, nausea, and vomiting. Therefore, we have observed anaphylatic reaction of bee-venom in 11 patients, who visited WonKwang University Kunpo Oriental Medical Center, treated bee venom. The results were summarized as follows : 1. The patient distribution ratio, in regard to sex, was shown to be 1 : 2.67 for male to females. In regard to age, it was shown that people in their 30's was the most predominant case, followed by people in their 20's, 30's, 50's and 60's, respectively. 2. When Anaphylaxis was occured, it was observed to abnormality of CBC, LFT, IgE, IgG. 3. In regard to patient condition, it was observed that fatigue was most frequent. 4. In regard to the number of times and quantity of bee venom inj., it was observed that anaphylaxis is most frequent at 7-10 times(1.6-2.0cc) 5. In regard to duration of reaction, it was observed that people in their l0min' was most frequent. In disappearing duration of anaphylaxic reaction, The results showed under 60min lcases(9%), 60-120min 7cases(64%) and 180-240min 3cases(27%). 6. In symptoms of anaphylaxis, The results showed hypotension 8cases(19%), itching sensation 7cases(16%), nausea 4cases(9%), erythema 4cases(9%) and dizziness 4cases(9%). In mentality, The results showed drowsy 8case(73%) and alert 3cases(27%). 7. Generally, patients were treated with Avil, Dexa IM and PDS, peniramine, cimetidine, Q-zyme per os after H/S, N/S inj. $O_2$ was supplied according to patient's symptom. In 1 severe case, Dopamine was iv injected.

수종의 레진 시멘트의 용해도와 수분흡착에 관한 연구

황유진,조인호,임주환,임헌송,Hwang Yu-Jin,Cho In-Ho,Lim Ju-Hwan,Lim Heon-Song 대한치과보철학회 2005 대한치과보철학회지 Vol.43 No.1

Statement of problem. Among the physical properties of adhesion luting cement, the aspect that requires the most important factor is the degree of solubility and water sorption. Dissolution or an inadequate due to excessive water sorption inside the oral cavity compromises the while concurrently increasing the susceptibility to secondary dental caries. Susceptibility to dissolution and difficulty of removing remnant cement from the gingival sulcus have hindered the use of dental resin cement in the clinical practice, but the improved characteristics of newer generation resin cements have interest in and enabled resin cements to be widely used in adhesion of fixed prosthesis, such as laminate veneers and all-ceramic crowns. Purpose. The purpose of this study is to compare and analyze the degrees of solubility and water sorption of a variety of resin cements widely used for clinical purposes with different curing methods. Material and methods. Self-curing resin cements, $Avanto^{(R)}$, $C&B^{TM}$ CEMENT and Superbond C&B cements comprised group 1, 2 and 3. The dual-curing resin cements $Panavian^{TM}$ F, $Calibra^{(R)}$ and $Variolink^{(R)}$ II were divided into groups 4, 5, and 6, respectively. The investigation was carried out using disc-shaped specimens as specified by ANSI/ADA Specification No. 27. The degree of water sorption, water solubility and lactic acid solubility of each test group was analyzed statistically leading to the following conclusion. Results. The degree of water sorption was shown to increase in the following order : group 6, 5, 4, 2, 1 and 3. There were significant differences between the water sorption of each group. Results of the degree of water solubility were shown to increase in the following order : group 6, 5, 4, 2, 1 and 3. Statistically significant differences were found between each group, with the exception of groups 1 and 3. Finally, the degree of lactic acid solubility was found to increase in the following order : group 6,5,4,2,3 and 1. Significant differences were found between each group. In general dual-curing resin cements displayed substantially lower values than self-curing resin cements with regard to water sorption, water solubility, and lactic acid solubility. Conclusions. From the results of this study, dual-curing resin cements show a significantly lower degree of water sorption and solubility than their self-curing counterparts. Clinically, when selecting resin cements, the product with a lower degree of water sorption and solubility are preferred. The results of this study indicate that the use-of dual-curing resin cements is preferable to self-curing cements.

봉약침을 이용한 류마토이드 관절염의 임상적 연구

황유진,이건목,황우준,서은미,장종덕,양귀비,이승훈,이병철,Hwang, Yoo-Jin,Lee, Geon-Mok,Hwang, Woo-Jun,Seo, Eun-Mi,Jang, Jong-Deok,Yang, Gui-Bi,Lee, Seung-Hoon,Lee, Byung-Chul 대한침구의학회 2001 대한침구의학회지 Vol.18 No.5

Objective : To evaluate the effect of treatment for Rheumatoid arthritis by using Bee-venom Acupuncture that is well known for anti-inflammatory effect and function of activating immune system. Methods : Evaluated the result of Bee-venom Acupuncture treatment twice in a week for patients who diagnosised as rheumatoid arthritis by 7 criteria of US Rheumatism Academy. Results : 1. If you see the distribution chart, sexual rate of male and female was 1:2.75 and age distribution shows as age ascend it shows high. 2. If you see the duration distribution, it shows chronic tendency in order of more than 6 months (59.5%), 2 to 5 months, and 1 month. 3. If you see the invaded region distribution, it shows chronic tendency in order of finger(17 cases), wrist joint(16 cases), knee joint(16 cases), ankle joint(10 cases), elbow joint(8 cases), shoulder joint(7 cases), feet(7 cases), hip joint(5 cases), low back(3 cases) and neck(2 cases). 4. If you see the result of duration distribution treatment, the improvement index is rising in order of within a month, 2 to 5 months, and over 6 months. So it shows that it has good result of treatment within a month. 5. If you see the invaded region, it shows high improvement index in order of low back, hop joint, shoulder joint, wrist joint, feet, knee joint, finger, elbow joint, ankle joint and neck. 6. If you see the result of morning stiffness time before treatment, it shows good effect of treatment in order of 2-3hrs, 30min.-an hr, an hr to 2hrs, and 0-30min. 7. If you see the patients satisfaction after Bee-venom Acupuncture treatment, Excellent is 6 cases, Good is 7 cases, and Moderate 2 cases. Conclusions : It will have greater treatment effect if herbal medicine, moxibustion, and acupuncture are used together as patients whole body condition and symptoms with Bee-venom Acupuncture for rheumatoid arthritis that is chronic inflammatory disease.

면진시스템을 적용한 중층 철근콘크리트 건축물의 내진성능효과

황유진 ( Hwang Yu Jin ),허무원 ( Hur Moo Won ),이용훈 ( Lee Yong Hun ),정현수 ( Jung Hyun Soo ),이상현 ( Lee Sang Hyun ) 한국구조물진단유지관리공학회 2019 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.23 No.2

경주지진 및 포항지진을 통해 우리나라도 지진의 안전지대가 아니라는 인식이 증가하면서 지진피해를 줄일 수 있는 내진 설계에 대한 관심이 증가하고 있다. 본 논문에서는 내진설계 기술 중 현재까지 가장 효과적인 방법의 하나로 알려져 있는 면진구조에 대하여 검토하고자 한다. 이를 위해 중층 RC 건축물에 면진시스템을 적용한 후 경계비선형동적해석을 통해 비면진건축물과 면진건축물의 내진성능효과를 비교 분석하였다.

모르타르 마감두께를 고려한 조적채움벽의 전단강도 평가

황유진(Yu-Jin Hwang),강혜령(Hye-Ryeong Kang),이상현(Sang-Hyun Lee) 한국콘크리트학회 2020 콘크리트학회논문집 Vol.32 No.6

공동주택의 냉난방 및 급탕 겸용 히트펌프의 에너지 성능 분석

황유진(Yu-Jin Hwang),강용권(Yong-Kwon Kang),조혜진(Hye-Jin Cho),조수영(Su-Young Jo),정재원(Jae-Weon Jeong) 대한설비공학회 2020 대한설비공학회 학술발표대회논문집 Vol.2020 No.6

Recently, the importance of reducing energy in buildings is more and more growing and feasible by applying an efficient machinery to handle building loads. This study analyzes the potential of arrangement of heat pumps in design and compares the energy performance of a boiler and several heat pump systems arranged by handling loads as the integrated cooling, heating and hot water supply systems. The specifications and details of the systems in energy simulation was referred to EnergyPlus model and performed through EES program. The result shows that a single heat pump combined with sufficient heat source system (case 1) consumed 50.3% less primary energy compared to the reference system. Double heat pump handling heating and hot water loads separately (case 2) requires 24.6% less primary energy than a reference boiler system. The energy consumption of cascade heat pump system (case 3) is 46.5% less than a reference system and 7% more than a single heat pump system.

감마선 조사 시 cotton linter 종이 내 수분이 셀룰로오스 열화에 미치는 영향

황유진 ( Yujin Hwang ),박해준 ( Hae-jun Park ),( Antje Potthast ),정명준 ( Myung-joon Jeong ) 한국목재공학회 2023 한국목재공학회 학술발표논문집 Vol.2023 No.1