선택적 레이저 용융 공정으로 제조된 AISI 316L 합금의 인장 및 충격 인성 특성에 미치는 응력 완화 열처리의 영향

양동훈,함기수,박순홍,이기안,Yang, Dong-Hoon,Ham, Gi-Su,Park, Sun-Hong,Lee, Kee-Ahn 한국분말재료학회 (*구 분말야금학회) 2021 한국분말재료학회지 (KPMI) Vol.28 No.4

In this study, an AISI 316 L alloy was manufactured using a selective laser melting (SLM) process. The tensile and impact toughness properties of the SLM AISI 316 L alloy were examined. In addition, stress relieving heat treatment (650℃ / 2 h) was performed on the as-built SLM alloy to investigate the effects of heat treatment on the mechanical properties. In the as-built SLM AISI 316 L alloy, cellular dendrite and molten pool structures were observed. Although the molten pool did not disappear following heat treatment, EBSD KAM analytical results confirmed that the fractions of the low- and high-angle boundaries decreased and increased, respectively. As the heat treatment was performed, the yield strength decreased, but the tensile strength and elongation increased only slightly. Impact toughness results revealed that the impact energy increased by 33.5% when heat treatment was applied. The deformation behavior of the SLM AISI 316 L alloy was also examined in relation to the microstructure through analyses of the tensile and impact fracture surfaces.

견관절의 임상적 평가도구에 관한 고찰

양동훈,김건형,김행범,최양식,박영배,Yang, Dong-Hoon,Kim, Kun-Hyung,Kim, Haeng-Beom,Choi, Yang-Sik,Park, Young-Bae 대한침구의학회 2007 대한침구의학회지 Vol.24 No.6

Objectives : A number of instruments have been developed to measure the quality of life in patients with various shoulder disorders. Much progress has been made in this area, and currently an appropriate instrument exists for each shoulder state. The purpose of this study is to review the instruments that are currently in use for assessing the shoulder joint. Methods : A literature research was performed to choose appropriate scales for assessment of function and the disability of the shoulder. Theoretically based scales were selected for review. Therefore, 11 scales were reviewed. The status of scales involved in shoulder treatment of acupuncture throughout several countries was evaluated. Results : 11 scales: The American shoulder and elbow surgeons evaluation form(ASES), Constant Shoulder Score, The disabilities of the arm, shoulder and hand(DASH), Shoulder Disability Questionnaire (SDQ), The Shoulder Pain And Disability index(SPADI), The simple shoulder test(SST), Oxford Shoulder Questionnaire(OSQ), The Rotator Cuff quality-of-life Measure(RC-QoL), Western Ontario Shoulder Instability Index(WOSI), Western Ontario Osteoarthritis of the Shoulder Index(WOOS), Western Ontario Rotator Cuff Index(WORC), wereevaluated. Each measurement has its own composition and characteristics. Their validity, reliability, responsiveness and practical characteristics were already evaluated. We found 3 domestic and 10 overseas papers about shoulder treatments using acupuncture assessed with shoulder scales. Conclusions : In clinical research, the selection of the measurement scale should take account of the condition of disease, the patient's traits and the characteristics of the research. Moreover, appropriate scales, which havevalidity, reliability, responsiveness and practical characteristics, are needed to enhance the quality of research.

선택적 레이저 용융법으로 제조된 Ti-6Al-4V 합금의 고 주기 피로 특성에 미치는 건식 전해 연마의 영향

양동훈,김영균,황유진,김명세,이기안,Yang, Dong-Hoon,Kim, Young-Kyun,Hwang, Yujin,Kim, Myoung-Se,Lee, Kee-Ahn 한국분말야금학회 2019 한국분말재료학회지 (KPMI) Vol.26 No.6

Additively manufactured metallic components contain high surface roughness values, which lead to unsatisfactory high cycle fatigue resistance. In this study, high cycle fatigue properties of selective laser melted Ti-6Al-4V alloy are investigated and the effect of dry-electropolishing, which does not cause weight loss, on the fatigue resistance is also examined. To reduce the internal defect in the as-built Ti-6Al-4V, first, hot isostatic pressing (HIP) is conducted. Then, to improve the mechanical properties, solution treatment and aging are also implemented. Selective laser melting (SLM)-built Ti64 shows a primary α and secondary α+β lamellar structure. The sizes of secondary α and β are approximately 2 ㎛ and 100 nm, respectively. On the other hand, surface roughness Ra values of before and after dry-electropolishing are 6.21 ㎛ and 3.15 ㎛, respectively. This means that dry-electropolishing is effective in decreasing the surface roughness of selective laser melted Ti-6Al-4V alloy. The comparison of high cycle fatigue properties between before and after dry-electropolished samples shows that reduced surface roughness improves the fatigue limit from 150 MPa to 170 MPa. Correlations between surface roughness and high cycle fatigue properties are also discussed based on these findings.

동결견(凍結肩) 환자의 동서협진 치료의 임상효과 비교연구 - 견관절 가동운동범위(ROM) 변화를 중심으로 -

남동우,김행범,양동훈,임사비나,김건식,이두익,이재동,최도영,이윤호,Nam, Dong-Woo,Kim, Haeng-Beom,Yang, Dong-Hoon,Lim, Sa-Bi-Na,Kim, Keon-Sik,Lee, Doo-Ik,Lee, Jae-Dong,Choi, Do-Young,Lee, Yun-Ho 대한침구의학회 2006 대한침구의학회지 Vol.23 No.5

Objectives : To establish an effective collaborate medicine treatment of acupuncture and western medicine for treating frozen shoulder patients. Methods : 59 voluntary patients were randomly assigned to Eastern treatment group(E group, n=22), Western treatment group(W group, n=17) and East-West treatment group(EW group, n=20). The E group received acupuncture treatment on LI15, TE14, GB21 and Master Dong's acupuncture points, Shin-gwan and Gyun-joong, twice a week for 4 weeks. The W group received suprascapular nerve block, subacromial injection and trigger point injection, twice a week for 4 weeks. The EW group received acupuncture and injection treatment including nerve block All groups were instructed to practice self exercise during their daily lives. Evaluations were made before treatment and after treatment based on the change in shoulder Range of Motion(ROM) and the patient's satisfaction concerning the treatment was measured by Visual Analogue Scale(VAS). The obtained data were analyzed and compared. Results : The patient's satisfaction scores were E group 5.67, W group 7.73 and EW group 7.67. The E group and the EW group showed significant improvement in abbduction, adduction and flexion(p<0.05). The W group showed significant improvement in adduction(p<0.05). Abduction significantly improved(p<0.05) in the EW group compared to E group and W group. Flexion also showed improvement in the EW group, but the difference among the 3 groups was statistically insignificant. The three group's difference of change in extension and adduction was insignificant(p>0.05). Conclusion : Acupuncture and nerve block alone significantly improved ROM in frozen shoulder patients. Also collaborate treatment of acupuncture and nerve block significantly improved ROM in frozen shoulder patients. But the difference of the three treatments were significant only for improving abduction(p<0.05).

성별다양성이 한국 사무직 근로자의 이직에 미치는 영향

양동훈(Dong Hoon Yang),최형준(Hyung Jun Choi) 한국인적자원관리학회 2023 인적자원관리연구 Vol.30 No.1

본 연구는 성별다양성이 남성과 여성의 자발적 이직에 미치는 영향을 조사하였다. 본 연구는 성별다양성을 Blau 지수로 정의하고 남성과 여성의 자발적 이직에 미치는 영향을 확인하였다. 한국노동연구원의 사업체 패널 자료 2007년에서 2013년까지 중 4개년치의 자료를 이용하여 사무직종 중심의 사업장 중 남성 구성원이 여성 구성원보다 많은 사업장만을 대상으로 패널분석을 실시하였다. 연구 결과에 의하면 성별다양성은 남성의 자발적 이직에 유의한 정(+)적 영향을 미쳤으며, 여성의 자발적 이직에는 유의한 부( - )적 영향을 미쳤다. 성별다양성의 증가로 인해 기존 주류집단이었던 남성 구성원들의 유사성과 매력이 감소하였기 때문에 남성의 자발적 이직은 증가했을 것으로 판단된다. 또한 성별다양성의 증가는 소수집단이 차별받지 않고 일할 환경을 형성하고 조직에 대한 신뢰와 만족감을 증가시키기 때문에 여성의 자발적 이직을 감소시켰을 것이다. 이는 주류집단이 남성인 조직에서 성별다양성의 증가가 여성 집단과 남성 집단의 이직률에 다른 영향을 미치는 것을 보여주는 결과이다. 또한 최초 지배 성별을 고려하는 것과 고려하지 않는 것의 결과 차이를 비교해보기 위해 추가분석을 실시하였다. 주요 직종이 사무직종인 모든 사업장을 대상으로 성별다양성이 남성과 여성의 자발적 이직에 미치는 영향을 검증하였다. 성별다양성은 남성의 자발적 이직에 유의한 영향을 미치지 않는 것으로 나타났으며, 여성의 자발적 이직에는 유의한 영향을 미치는 것으로 나타났다. 즉, 최초 지배 성별을 고려하는 것과 고려하지 않는 것은 결과에 차이가 있었다. 이러한 결과들은 최초 지배 성별을 구분하여 성별다양성 연구를 진행해야 함을 시사한다. 후속 연구에서는 최신 데이터를 포함한 종단 자료를 활용하여, 다양한 업종과 직종을 대상으로 성별다양성이 남성과 여성의 자발적 이직에 미치는 차별적인 영향을 분석하는 시도가 필요할 것으로 판단된다. This study is to find the effect of gender diversity on the voluntary turnover of men and women. In this study, gender diversity is measured by the Blau index to confirm its effect on the voluntary turnover of men and women. Panel analysis was conducted only for the workplace which has more male office workers than female ones using four years of Workplace Panel Survey data from the Korea Labor Institute from 2007 to 2013. According to the result of the research, gender diversity caused a meaningful positive effect on the voluntary turnover of men and a meaningful negative effect on the voluntary turnover of women. It is thought that the voluntary turnover of men was increased because the similarity and attraction of the male members, who used to be the majority, decreased due to the increased gender diversity. Also, it is thought that the voluntary turnover of women decreased because the increased gender diversity created an environment that did not discriminate against the minority and enhanced trust and satisfaction toward the organization. This result shows that the increased gender diversity affects differently the turnover rate of the men and the women in the organization of which the majority are male members. Additionally, an analysis was conducted to compare the difference in results between considering and not considering the initial dominant gender. The effect of gender diversity on voluntary turnover of men and women was verified for all workplaces where the main occupation is office working. Gender diversity did not significantly affect men's voluntary turnover, and it had a significant effect on women's voluntary turnover. In other words, there was a difference in the results between considering and not considering the initial dominant gender. These results show that research on gender diversity should be conducted after distinguishing the initial dominant gender. It is thought to be necessary to try to analyze the differential effect of gender diversity on the voluntary turnover of men and women in various types of business and occupation, using the longitudinal data including the latest data in the follow - up research.

노사관계환경과 다국적 기업의 생산결정에 관한 연구

양동훈(Dong Hoon Yang) 한국고용노사관계학회 1999 産業關係硏究 Vol.9 No.1

골격지도에서 개별 목표를 갖는 두 이동로봇의 충돌 회피 알고리즘

양동훈(Dong-Hoon Yang),홍석교(Suk-Kyo Hong) 제어로봇시스템학회 2006 제어·로봇·시스템학회 논문지 Vol.12 No.7

맥솔(脈率)과 심박변이도(心搏變移度)의 상관성(相關性) 연구(硏究)

양동훈 ( Dong-hoon Yang ),박영배 ( Young-bae Park ) 대한한의진단학회 2006 大韓韓醫診斷學會誌 Vol.10 No.2

Background: Pulse-respiration ratio has been used for estimating subject`s status in oriental medicine. Pulse and respiration is strongly associated with autonomic nerve system. But there is no research about correlation between pulse-respiration ratio and autonomic nerve system. Objectives: We performed this study to know correlation between pulse-respiration ratio and HRV(heart rate variability) that shows autonomic nerve system status well and to clarify clinical meaning of pulse-respiration ratio. Methods: After subject`s 10 minutes rest, we measured subject`s ECG, respiration pattern and HRV. In this research, subject`s number is 95(Male 50/Female 45). We calculated pulse-respiration ratio from ECG and respiration pattern. Then, we analyzed correlation between pulse-respiration ratio and HRV parameters in all subjects, 2 group divided by Wan-Maek(P-R ratio 4.28). We tried to compare HRV parameters among Wan-Maek, Sak-Maek and Ji-Maek group. Correlation analysis between pulse-respiration Ratio and pulse rate, respiration rate is performed. Finally correlation analysis between Respiration and HRV parameters in all subjects, 2 group divided by Wan-Maek(4.28) is studied. Results: 1. Mean pulse-respiration is 4.10±0.67, Mean pulse rate is 68.06±7.82bpm, Mean respiration rate is 16.81±2.72 times per minute in all subjects. 2. Correlation analysis between pulse-respiration ratio and HRV parameters of high pulse-respiration ratio group is not Significant. But, in low pulse-respiration ratio group, HFnorm(correlation coefficient 0.306, p= 0.018), InHF (0.308, p=0.002) is sig-nificantly correlated with pulse-respiration ratio. 3. Comparison of HRV parameters among Wan-Maek, Sak-Maek and Ji-Maek Group is not significant. 4. Pulse-respiration ratio is more affected by respiration rate(correlation coefficient -0.717, p= 0.000) than pulse rate (correlation coefficient 0.396, p=0.000). 5. Correlation analysis between respiration rate and HRV parameters of high pulse-respiration ratio group is not significant. But, in low pulse-respiration ratio group, HFnorm (correlation coefficient -0.327, p=0.011), LF/HF(0.346, p=0.007), 1nHF (-0.355, p=0.006) are significantly correlated with respiration rate. Conclusions: Pulse-respiration ratio and parasympathetic index has positive correlation. The closer Wan-maek, The higher parasympathetic index in low pulse-respiration ratio group. Respiration rate is more related with pulse-respiration ratio than pulse rate. Respiration is negatively correlated with autonomic parameters. And the slower respiration, the higher parasympathetic index in low pulse-respiration ratio group.

최고경영자 윤리경영의 제도화 도입과정: 한국콜마 사례를 중심으로

양동훈 ( Dong Hoon Yang ),고은정 ( Eun Jung Ko ) 한국윤리경영학회 2016 윤리경영연구 Vol.16 No.1

급변하는 경영환경 속에서 기업의 사업영역은 점차 다국화 되었고, 기업의 범위는 국가를 넘어 세계가 하나의 시장이 되었다. 이에 기업의 사회적 책임(CSR)에 대한 관심이 높아지고 있지만 CSR에 관한 논의는 주로 다국적기업과 대기업에 초점을 맞추어 진행되었고, 중소기업은 대기업의 CSR 활동 대상으로 인식되어 왔다. 중소기업의 경우, CSR을 도입하더라도 자본과 인력이 풍부한 대기업에 비해 기업에 돌아오는 보상적 측면이 적게 느껴지기 때문에 CSR의 필요성은 알지만 도입을 주저하고 있는 현실이다. 때문에 중소기업의 경우에는 CEO의 윤리경영 실천의지가 굉장히 중요하다. CEO가 확고한 신념을 가지고 CSR을 추진하기 위한 적극적인 의지를 표명하고 솔선수범을 보일때 조직의 윤리풍토가 구축될 수 있기 때문이다. 또한 조직의 규모가 작은 경우에는 CEO의 경영철학이 곧 조직문화화 될 수 있기 때문이다. 본 사례연구에서는 CEO의 강한 의지를 기반으로 윤리경영이 조직문화화 된 한국콜마의 사례를 중심으로 제도화의 필요성에 대해서 살펴보려 한다. 이를 위해 기업에서 윤리경영 도입 시에 추진하는 ‘윤리경영 도입 3단계’를 토대로 향후 한국콜마가 나아가야 할 발달단계를 제안함으로써 중소기업들이 윤리경영 도입 시 필요한 사안들을 제안하고자 한다. In the rapidly changing business environment, the world has become one of the market beyond the country. There has been a growing interest in corporate social responsibility(CSR). CSR is the topic as broad agenda, which is the need to be processed in all of the organization. However, Korean companies’ activities regarding CSR are limited to major companies. CSR level of small and medium-sized businesses is still insufficient level. In the case of small and medium-sized businesses, CEO’s practical volition of business ethics is very important. This case study, by using the “introduction of three stages of ethical management”, analyzed the CSR stage of the Korea Kolmar. This study would give advice what is the most important factor to manage with business ethics

소화기 ; 단일 의료기관에서 경험한 자발성 장벽내 혈종 14예에 대한 임상적 고찰

양동훈 ( Dong Hoon Yang ),김진호 ( Jin Ho Kim ),박성호 ( Seong Ho Park ),양석균 ( Suk Kyun Yang ),변정식 ( Jeong Sik Byeon ),명승재 ( Seung Jae Myung ),김경조 ( Kyung Jo Kim ),예병덕 ( Byong Duk Ye ),고창옥 ( Chang Ok Koh ),윤순민 대한내과학회 2010 대한내과학회지 Vol.79 No.5

목적: 자발성 장벽내 혈종은 대부분 항응고 치료의 드문 합병증으로 발생하며, 최근 항응고제 사용 증가로 이 질환의 빈도도 증가할 것으로 추정된다. 저자들은 자발성 장벽내 혈종의 임상적 특징과 예후에 대해 분석하고자 하였다. 방법: 2001년 3월부터 2009년 2월까지 서울아산병원에서 특징적 CT 소견으로 자발성 장벽내 혈종으로 진단 후 치료받은 14예의 의무기록을 후향적으로 분석하였다. 결과: 환자들의 연령 중앙값은 67세였고, 심방세동, 심장판막 치환술, 허혈성 뇌졸중 등의 동반 질환을 가지고 있었으며, 모두 항응고제를 복용하고 있었다. 발현 증상은 복통(14명), 구역/구토(9명), 흑색변/혈변(8명) 등이었다. 내원 시 international normalized ratio (INR)의 중앙값은 7.7 (1.6~15.1이상)이었고, 13명(93%)에서 INR이 3.5 이상이었다. 하행결장에 발생한 1예를 제외하고 모두 소장에 발생하였는데, 공장 및 회장이 각각 7명, 4명으로 호발 부위였다. 금식 및 항응고제 중단, 신선동결혈장과 비타민 K 투여를 통한 응고장애 교정 등 보존 치료로 모두 호전되었다. 증상 호전과 응고장애 교정 후 12명에서 항응고 치료를 재개하였고, 평균37.4개월의 추적 기간 동안 재출혈 등 합병증은 발생하지 않았다. 결론: 자발성 장벽내 혈종은 주로 항응고제 과다 사용 시발생하였고, 보존 치료로 빠르게 호전되었으며, 항응고 치료재개 후에도 재출혈 등의 합병증은 없었다. 추후 대규모 연구를 통해 항응고 치료 재개의 안전성 및 재개 시점에 대한 확인이 필요하다. Background/Aims: Spontaneous intestinal intramural hematoma is a rare complication occurring most commonly in patients receiving anticoagulant therapy. The present study aimed to analyze the clinical features and prognosis of this condition. Methods: We retrospectively analyzed the medical records of 14 patients who were diagnosed with spontaneous intestinal intramural hematoma based on characteristic computed tomography findings and treated for this condition at Asan Medical Center from March 2001 to February 2009. Results: The median age of patients was 67 years. All patients were receiving anticoagulant therapy. The most common presenting symptoms were abdominal pain (14 patients), nausea/vomiting (9 patients), and melena/hematochezia (8 patients). The median international normalized ratio (INR) was 7.7 (1.6- >15.1). The INR was above 3.5 in 13 patients (93%). Hematomas most commonly involved the jejunum (7 patients), followed by the ileum (4 patients). All patients rapidly recovered without short-term complications after medical treatment, including correction of coagulation abnormalities. Twelve patients resumed anticoagulant therapy after symptomatic resolution and correction of coagulation abnormalities, and no complications, including rebleeding, occurred during the mean 37.4 months of follow-up. Conclusions: Spontaneous intestinal intramural hematoma rapidly improved after medical treatment, and no complications occurred. It may be safe to carefully resume anticoagulant therapy in patients at high risk of thromboembolism. (Korean J Med 79:518-525, 2010)