GPS를 활용한 포지션별 남자 럭비 세븐스 움직임 특성 분석

김동후(Kim, Dong-Hoo),김지응(Kim, Ji-Eung),김재홍(Kim, Jae-Hong) 한국체육과학회 2021 한국체육과학회지 Vol.30 No.6

The purpose of this study is to quantify the movements of the men"s rugby 7s national team in international matches to confirm the characteristics of each position. In order to achieve the purpose of the study, movement information was collected in real time using wearable devices in 5 winning and 5 losing games. The collected information was confirmed by one-way ANOVA and two-way ANOVA of the difference between the first and second half and the win/loss according to the position. As a result, forward players played a lot in the first half and the losing game, and the average heart rate was high in the second half and the winning game. The maximum velocity was found to run fast in the first half and winning games. The white players played a lot in the first half and the losing game, and the average heart rate was high in the first half and the winning game. The maximum velocity was found to run fast in the first half and defeat games. Based on these results, it is expected to be used as basic data for training program development and intensity setting.

The Persuasive Impact of Fit between Message Goals(Promotion vs. Prevention) and Modality of Message on Social Media

Dong Hoo Kim(김동후),Young-A Song(송영아) 한국콘텐츠학회 2021 한국콘텐츠학회논문지 Vol.21 No.2

커뮤니케이션 수단으로서의 소셜미디어의 성장은 소비자가 영양학적 선택과 건강한 음식 소비를 하는 데 소셜미디어의 영향력 역시 증가시켰다. 이 연구는 소셜미디어 상에서 건강한 식습관과 관련한 메시지 목표(향상 vs. 예방)와 메시지 형식(텍스트 vs. 이미지)이 메시지 설득력에 미치는 영향력을 알아보는 데 그 목적이 있다. 연구 결과에 따르면, 향상메시지에 노출된 참가자들은 소셜미디어 메시지 형식에 따른 차이를 보이지 않았으나, 예방메시지에 노출된 참가자들은 텍스트 (vs. 이미지) 형식의 메시지에 노출되었을 때, 메시지에 대한 더 긍정적인 태도를 보였으며, 해당 메시지에 대해 더 높은 클릭 의도를 보였다. 본 연구의 결과는 소셜미디어 상 건강메시지의 형식과 메시지 목표의 적합성이 메시지 효과에 영향을 미침을 이론적으로 증명하였다. 더불어 효과적인 건강메시지 작성 및 전달 방식에 대한 실무적 지침 역시 제공하리라 예상한다. Examination of the concurrent evolution of communication tools and eating behaviors over recent decades reveals that social media and other forms of digital content have become powerful new driving forces for nutritional choices and food consumption. The purpose of this research was to examine the effect between goal orientation of message (promotion versus prevention) and the type of message (text versus image) on effectiveness of the message. The findings showed that individuals exposed to a promotion-focused message similarly responded to the message regardless of the type of the message. By contrast, those who exposed to a prevention-focused message showed significantly more positive responses to the message posted on the text-based social media than the message on the image-based social media. The findings indicated that, if presented effectively, social media could be harnessed to promote healthier eating habits and behaviors, prevent those which can be harmful, and ultimately improve an individual’s daily food consumption and overall quality of life.

택시표시등광고 효과에 관한 연구 : 아이트래커 측정 및 인식조사를 중심으로

김동후(Kim, Dong-hoo),김운한(Kim, Woon-han),김신엽(Kim, Shin-yup),심성욱(Shim, Sung-wook) 한국광고홍보학회 2022 한국광고홍보학보 Vol.24 No.4

본 연구는 현재 시범사업 중인 택시표시등광고 효과를 통합적으로 알아보기 위한 것으로, 다방법적(multi method) 접근에서 아이트래커 실험과 인식조사를 실시하고 물리적, 맥락적 측면의 감각 및 인지, 태도 변인들의 영향력을 살폈다. 우선, 아이트래커 실험 결과는 다음과 같다. 첫째, 광고의 시각적 이해가 이루어질 수 있는 시선 고정시간(SD) 0.3초 이상의 시간을 확보하여 의미 있는 주목 효과를 얻은 것이 확인되었다. 둘째, 시선 점유시간(VD)은 평균 1.28초, 시선고정시간(FD)은 평균 1.24초로 목격 순간 96%의 높은 집중도를 보였으며, 광고 보조인지에서도 높은 재인율을 보였다. 셋째, 상업지역에서 운전자의 택시표시등광고 매체 주목은 43.4회로 시선 고정빈도(FC) 기준 약 6.5%의 시선점유율을 나타낸 반면, 주거지역에서 시선점유율은 약15.7%로 주거지역 시선 점유율이 더 높았다. 다음으로, 서울, 인천, 대전 시민을 대상으로 한 인식조사 결과는 첫째, 버스, 버스쉘터, 택시광고, 지하철 광고에 대한 인지도는 평균 이상이며, 평균 인지율은 98% 이상으로 나타났다. 반면 다른 옥외매체 대비 택시표시등광고의 노출빈도가 상대적으로 적었다. 둘째, 지역별 인지도 및 노출 빈도의 경우 서울과 대전, 인천 지역간 유의한 차이가 나타나지 않았다. 셋째, 광고태도, 주목도는 평균값 이상인 반면 구매영향력에 대한 평가는 평균에 미치지 못하였다. 넷째, 택시표시등광고의 안전도와 관련하여 표시등의 밝기, 택시표시등 크기 등의 순으로 안전에 영향을 줄 것이라는 우려가 있었다. 다섯째, 도시미관 및 경관에 긍정적인 영향을 미칠 것이라는 응답은 평균 이하로 나타났다. 연구결과를 바탕으로 택시표시등광고 운영에 관한 몇 가지 실질적이고 타당한 방안을 제안하였다. This study aims to examine comprehensively the sensory and cognitive responses to taxicab advertisements using both an eye-tracker experiment and cognitive survey as a multi-method approach. The results of the eye tracking experiment are as follows. First, a meaningful attention effect was obtained by securing a gaze fixation time (SD) of 0.3 seconds or more for visual understanding. Second, the average gaze occupancy time (VD) was 1.28 seconds and the gaze fixation time (FD) averaged 1.24 seconds, showing a high concentration of 96% at the moment of sighting, a high recognition rate. Third, the driver’s attention on taxicab ad advertising media in commercial areas was 43.4 times, showing a gaze share of about 6.5% based on the frequency of gaze fixation (FC), while in residential areas, the gaze share was about 15.7%, higher than in commercial areas. The results of the survey are as follows. first, the awareness of transit ad including taxicab ads was above average, average awareness rate was above 98%, while the exposure frequency of taxicab ads was relatively low. Second, no significant difference was found among Seoul, Daejeon, and Incheon in regional awareness and exposure frequency. Third, attitude toward ad and attention level were above the average, while the evaluation of purchase influence was below the average. Fourth, as to the safety of taxicab ads, some concern of the brightness of the light and the size of the taxi light were found. Fifth, perception of the positive effect on the aesthetics and landscape of the city was below the average. Based on the results, several practical and reasonable measures for the operation of taxicab ads were proposed.

정적변위센서를 이용한 콘크리트부재의 손상검토

김이성 ( Kim Ie-sung ),최영화 ( Choi Young-wha ),김동후 ( Kim Dong-hoo ) 한국건축시공학회 2011 한국건축시공학회 학술발표대회 논문집 Vol.11 No.2

절삭실험을 이용한 저합금강의 유동응력 결정 및 검증

안광우(Kwang-Woo Ahn),김동후(Dong-Hoo Kim),김태호(Tae-Ho Kim),전언찬(Eon-Chan Jeon) 한국기계가공학회 2014 한국기계가공학회지 Vol.13 No.5

A technique based on the finite element method (FEM) is used in the simulation of metal cutting process. This offers the advantages of the prediction of the cutting force, the stresses, the temperature, the tool wear, and optimization of the cutting condition, the tool shape and the residual stress of the surface. However, the accuracy and reliability of prediction depend on the flow stress of the workpiece. There are various models which describe the relationship between the flow stress and the strain. The Johnson-Cook model is a well-known material model capable of doing this. Low-alloy steel is developed for a dry storage container for used nuclear fuel. Related to this, a process analysis of the plastic machining capability is necessary. For a plastic processing analysis of machining or forging, there are five parameters that must be input into the Johnson-Cook model in this paper. These are (1) the determination of the strain-hardening modulus and the strain hardening exponent through a room-temperature tensile test, (2) the determination of the thermal softening exponent through a high-temperature tensile test, (3) the determination of the cutting forces through an orthogonal cutting test at various cutting speeds, (4) the determination of the strain-rate hardening modulus comparing the orthogonal cutting test results with FEM results. (5) Finally, to validate the Johnson-Cook material parameters, a comparison of the room-temperature tensile test result with a quasi-static simulation using LS-Dyna is necessary.

상완 골두 골괴사증에서의 관절경하 핵심 감압술 - 수술 술기 -

조철현,손승원,배기철,김동후,Cho, Chul-Hyun,Sohn, Sung-Won,Bae, Ki-Cheor,Kim, Dong-Hoo 대한관절경학회 2009 대한관절경학회지 Vol.13 No.2

Purpose: We introduce arthroscopic assisted core decompression for humeral head osteonecrosis. Operative technique: After diagnostic shoulder arthroscopy is performed using posterior and anterior portal, we make a 2 cm lateral skin incision approximately 3 cm distal to 1/3 of lateral margin of the acromion and place short gray cannula to prevent adjacent soft tissue injury when insert guide pin. Under C-arm fluoroscopic and arthroscopic guidance, 3 to 4 guide pins are inserted toward the necrotic area. Then we perform drilling using 7.0 mm reamer. Conclusion: We believe this technique is a less invasive approach and avoids the complications comparing to deltopectoral approach. Arthroscopic assisted core decompression is an effective procedure in management of early stage of the humeral head osteonecoris.

중장비 크레인용 쉬브 핀 적용을 위한 새로운 설계식 제안

김범준(Bum-Joon Kim),김동후(Dong-Hoo Kim) 한국기계가공학회 2025 한국기계가공학회지 Vol.24 No.1

Cranes are essential heavy equipment used primarily for moving heavy objects in industrial facilities. Ensuring structural safety is crucial, as cranes must operate safely under various load ranges and working environments. Safety evaluation procedures and methods are guided by industrial safety standards. However, these evaluations are often limited due to the large-scale construction of crane structures and the complexity of their operating environments. In Korea, the structural safety of crane components is primarily assessed using standardized design methods. Among these components, pins that are responsible for bearing loads such as shear and bending at the junction between parts and booms are critical for maintaining crane safety. Unfortunately, general design methods often fall short in adequately addressing these components. To address this gap, this study proposes a modified design equation tailored for shear and bending scenarios, considering the design dimensions of the boss and yoke for crane sheave pins. The safety of this modified approach is thoroughly examined. In addition, the design integrity of the crane sheave pin joint element is evaluated through finite element analysis utilizing the proposed design dimensions.

회전형 저온 플라즈마 시스템을 이용한 분말식품의 균일한 살균 연구

김명찬,박덕모,한진수,우인봉,김동후,장성은,윤찬석,김인,Kim, Myung Chan,Park, Duck Mo,Han, Jin Soo,Woo, In Bong,Kim, Dong Hoo,Jang, Seong Eun,Yoon, Chan Suk,Kim, In 한국식품영양학회 2018 韓國食品營養學會誌 Vol.31 No.2

In this study, a relatively effective process is used to sterilize Escherichia coli on the surface of micro-sized calcium citrate powder using nitrogen and argon as process gases in a low-temperature vacuum plasma treatment. The purpose of this study is to confirm and to introduce the effectiveness of homogeneous surface treatment for the sterilization of fine inorganic powder by the rotatable low-temperature RF plasma system designed by ourselves. The results of the test using 3M petrifilm showed that there were no remarkable spots in the case of the surface of plasma treated powder, whereas the untreated powder showed many blue spots, which indicating that the E. coli was alive. After 5 days, in the same samples, the blue spots were seen to be larger and darker than before, while the plasma-treated powder showed no changes. The results from FE-SEM analysis showed that the E. coli was damaged and/or destroyed by reactive species generated in the plasma space, resulting in the E. coli being sterilized. Furthermore, the sterilization effects according to the selected parameters ($N_2$ and Ar; flow rate 30 and 50 sccm) adapted in this study were mutually similar, regardless of such different process parameters, and this indicates that homogeneous treatment of powder surfaces could be more effective than conventional methods. Therefore, the plasma apparatus used in this study may be a practical method to use in a powerful sterilization process in powder-type food.

Variational 방법으로 구한 필드 분포를 이용한 도파로 폭에 따른 Buried Channel Waveguides의 단면 반사율

金相澤(Sang-Taek Kim),金東厚(Dong-Hoo Kim),金富均(Boo-Gyoun Kim) 大韓電子工學會 2000 電子工學會論文誌-SD (Semiconductor and devices) Vol.37 No.11

Buried channel waveguides의 필드 분포에 대한 analytic 표현식을 effective index method (EIM), variatioanl method(VM)와 각각의 방향으로의 경계조건을 적용한 variational method (VM_vec)를 사용하여 구한 뒤 angular spectrum 방법을 적용하여 도파로 폭에 따른 단면 반사율을 계산하고 이를 비교 검토하였다. 도파로 폭이 커질수록 buried channel waveguides의 단면 반사율은 slab 도파로의 단면 반사율에 접근하였고 도파로 폭이 작아질수록 slab 도파로의 단면 반사율로부터 quasi-TE 모드의 단면 반사율은 감소하였고 quasi-TM 모드의 단면 반사율은 증가하였다. 도파로 폭에 따른 단면 반사율 변화량은 quasi-TM 모드보다 quasi-TE 모드에 대한 변화량이 크게 나타남을 알 수 있었다. Aspect ratio가 1일 떼 VM과 VM_vec으로 구한 quasi-TE 모드와 quasi-TM 모드의 반사율은 거의 일치하였으나 EIM으로 구한 quasi-TE 모드와 quasi-TM 모드의 반사율은 차이가 크게 나타났다. Quasi-TE 모드의 경우는 VM_vec으로 구한 필드 분포에 angular spectrum 방법을 적용하여 계산한 단면 반사율이 EIM으로 구한 반사율보다 정확한 값임을 알 수 있었고 quasi-TM 모드의 경우는 각 방법으로 구한 반사율이 거의 같음을 볼 수 있었다. We calculate the facet reflectivity as a function of the waveguide width of buried channel waveguides using the angular spectrum method and the field profiles obtained by the effective index method, the variational method and the modified variational method, respectively and discuss the results. As the waveguide width increases, the facet reflectivity of buried channel waveguides approaches to that of slab waveguides. As the waveguide width decreases, the facet reflectivity of quasi-TE mode decreases from that of slab waveguides, while that of quasi-TM mode increases morf that of slab waveguides. The variation of the facet reflectivity of quasi-TE mode as a function of waveguide width is much larger than that of quasi-TM mode. When the aspect ratio is one, the difference between the facet reflectivity of quasi-TE mode and that of quasi-TM mode using the variational method and the modified variational method is negligible, while the difference between the facet reflectivity of quasi-TE mode and that of quasi-TM mode using the effective index method is large. In the case of quasi-TE mode, the facet reflectivity using the angular spectrum method and the field profiles obtained by the modified variational method could be more accurate than that obtained by the effective method. In the case of quasi-TM mode, the facet reflectivities obtained by the various methods are almost the same.

절삭력 최적화를 이용한 금형가공시 표면조도 및 형상 정밀도 비교에 관한 연구

이수용(Su Yong Lee),김동후(Dong Hoo Kim),한민식(Min Sik Han),전언찬(Eon Chan Jeon) (사)한국CDE학회 2012 한국 CAD/CAM 학회 학술발표회 논문집 Vol.2012 No.2

The mold is widely used for mass production in present industry. Also, product cycle time is faster, for this request, high productivity improvement in mold machining is required. And, In case of mold manufacturing company, the delivery shortening is required to quickly manufacture new product. Therefore, we aim for the delivery shortening though the method of machining time shortening in mold machining. On this paper, first, we made the NC-code of Insert die-casting as the object model using PowerMill. And then, analyzed cutting force by Toolpath in Insert mold machining using Production Module of Advantedge which is cutting force analysis program. After that, we came up with the optimum conditions of productivity improvement throughout the analysis result of before and after optimization of cutting force, machining time variation, and surface roughness by changing min tangential force to 80, 85, 90% of max tangential force.