자주포 보조동력장치 엔진 마운트 강도안전율 향상에 관한 연구

김병현,서재현,박영일,김용욱,김병호,Kim, Byung Hyun,Seo, Jae Hyun,Park, Young Il,Kim, Yong Wook,Kim, Byung Ho 한국군사과학기술학회 2016 한국군사과학기술학회지 Vol.19 No.3

The purpose of this study is to analyze the vibration characteristics and develop a mounting which can improve the strength safety factor to replace the high failure rate APU(auxiliary power unit) imported metal mounts with rubber mount that can be domestically produced. For this study, we analyzed in 3 kinds of rubber mounts hardness for the natural frequency to avoid the average excited frequency of the APU. In addition, allowed vibration acceleration of rubber mount confirmed to 90.8 g by adding a strength safety factor. To assure the validity of the design, we measure the vibration acceleration equipped with a metal mount and rubber mount 2 species(Hs 50 and 60). As a result, the proposed design method in this study is reasonable because the rubber mounts is excellent strength safety factor and vibration transmissibility than metal mounts.

통합 이미지 처리 기술을 이용한 콘크리트 교량 균열 탐지 및 매핑

김병현,조수진,Kim, Byunghyun,Cho, Soojin 한국안전학회 2021 한국안전학회지 Vol.36 No.1

In many developed countries, such as South Korea, efficiently maintaining the aging infrastructures is an important issue. Currently, inspectors visually inspect the infrastructure for maintenance needs, but this method is inefficient due to its high costs, long logistic times, and hazards to the inspectors. Thus, in this paper, a novel crack inspection approach for concrete bridges is proposed using integrated image processing techniques. The proposed approach consists of four steps: (1) training a deep learning model to automatically detect cracks on concrete bridges, (2) acquiring in-situ images using a drone, (3) generating orthomosaic images based on 3D modeling, and (4) detecting cracks on the orthmosaic image using the trained deep learning model. Cascade Mask R-CNN, a state-of-the-art instance segmentation deep learning model, was trained with 3235 crack images that included 2415 hard negative images. We selected the Tancheon overpass, located in Seoul, South Korea, as a testbed for the proposed approach, and we captured images of pier 34-37 and slab 34-36 using a commercial drone. Agisoft Metashape was utilized as a 3D model generation program to generate an orthomosaic of the captured images. We applied the proposed approach to four orthomosaic images that displayed the front, back, left, and right sides of pier 37. Using pixel-level precision referencing visual inspection of the captured images, we evaluated the trained Cascade Mask R-CNN's crack detection performance. At the coping of the front side of pier 37, the model obtained its best precision: 94.34%. It achieved an average precision of 72.93% for the orthomosaics of the four sides of the pier. The test results show that this proposed approach for crack detection can be a suitable alternative to the conventional visual inspection method.

백남준아트센터

김병현,Kim, Byeong-hyun 대한건축사협회 2008 建築士 Vol.2008 No.10

Black soldier fly (Hermetia illucens) larvae oil as an alternative fat ingredient to soybean oil in laying hen diets

김병현,Minji Kim,Jin Young Jeong,Hye Ran Kim,지상윤,정현정,Seol Hwa Park 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.9

Objective: The objective of this study was to determine whether dietary black soldier fly (Hermetia illucens, HI) larvae oil (HILO) could serve as an alternative fat source to soybean oil (SBO) in laying hen diets. Methods: We randomly assigned 25-week-old Hy-line Brown laying hens (n = 144) to receive (n = 6 hens/group; eight replicates) a control or an experimental diet in which SBO was replaced with 50% (50HILO) or 100% HILO (100HILO). Results: Dietary HILO did not negatively affect body weight or productive performance during the study. The eggs also had similar quality parameters, proximate composition, and cholesterol levels. However, the yolk color index was significantly higher (p<0.01) in the 100HILO than in the other groups. Dietary HILO significantly altered the composition of fatty acids (FAs) in abdominal fat and eggs. Total saturated fatty acids (SFAs) and total polyunsaturated FAs (PUFAs) were significantly increased and decreased in the 50HILO and 100HILO groups, respectively, compared with those in the control group (p<0.001 and p<0.0001, respectively). Specifically, the medium-chain FAs lauric and myristic acids were remarkably increased in the abdominal fat of laying hens fed HILO (p<0.0001), whereas only myristic acid increased in eggs (p<0.0001). Undesirable heavy metal (aluminum, fluorine, arsenic, lead, mercury, and cadmium) concentrations were below permissible limits in eggs. Conclusion: We considered that HILO could be an alternative dietary fat to SBO for laying hens with maintained productive performance and good egg quality.

Relaxation 기법을 이용한 병렬저수지 동시 붕괴 해석

김병현,한건연,Kim, Byeong-Hyeon,Han, Geon-Yeon 한국수자원학회 2017 물과 미래(한국수자원학회지) Vol.50 No.11

회원작품 - 여수문화예술공원 GS칼텍스 예울마루

김병현,Kim, Byeong-Hyeon 대한건축사협회 2012 建築士 Vol.2012 No.9

제지 공정 적용을 위한 Cellulase의 정제 특성 및 처리 조건 선정에 관한 연구

김병현,전양,Kim, Byung-Hyon,Jeon, Yang 한국펄프종이공학회 1998 펄프.종이기술 Vol.30 No.1

The main protein peak was observed in fraction No.9 and 109 when cellulase seperation was conducted by use of DEAE-Sephadex. The protein obtained from fraction No.9 has the characteristics of Cx component and that from fraction No.109 characteristics similiar to $C_1$ component. The effective reaction condition of the ensyme used was $40^{\circ}C$ in temperature. pH 5.0 and 90 minutes in treatment time. For the case of $C_1$ pH 5.5 in temperature range of $30^{\circ}C 50^^{\circ}C$, 4.0 5.5 in pH, and over 30 minutes of treatment time, the reaction was in the range of 80% of the maximum. Affinity of enzyme increased as freeness, increased, and this effect was more visible in fiber than in fines.

CelIulase 구성 요소별 처리에 의한 펄프 섬유의 특성 변화

김병현,전양,Kim, Byung-Hyon,Jeon, Yang 한국펄프종이공학회 1998 펄프.종이기술 Vol.30 No.2

Two major cellulase components purified with sephadex G-75 and DEAE sepharose were applied to bleached kraft pulp to inverstigate the change of fiber properties. Cellulose viscosity was very sensitive to $C_x$ component treatment (more than 15% drop was observed) while being little influenced by $C_1$, component (only 2% drop). Fiber fraction longer than 2mm was reduced by $C_x$ treatment while short fiber fraction was increased greatly by more than 15%. There was little change in fiber length distribution by combined treatment of $C_1$ 1 and $C_x$ at equal. In this case, fine contents increased by more than 2.5% at equivalent refining time. WRV and Density were increased as the amount of $C_1$ or $C_x$ treatment was increased. $C_{x}$ was main cause for increasing them. But the effect fell as enzyme dosage.

홍수범람지도 작성을 위한 GIS기반 1차원 동역학적 해석 기법

김병현,최승용,한건연,Kim. Byung-Hyun,Choi. Seung-Yong,Han. Kun-Yeon 한국방재학회 2011 한국방재학회논문집 Vol.11 No.6

홍수는 한 국가의 발전에 영향을 미칠 수 있는 주요 자연재해 중 하나이다. 세계 각국에서는 댐, 저류지, 제방 등과 같은 수공 구조물의 설계빈도를 초과하는 이상 홍수가 발생할 경우에 대비하여 비구조적 대책의 일환으로 홍수범람지도를 작성하고 있다. 본 연구는 댐 붕괴에 대한 1차원 하천수리해석 모형(DAMBRK)과 GIS를 연계한 홍수범람지도 작성 방법에 관해 보여준다. 이를 위해 여러 가지의 댐 붕괴 시나리오에 따라 붕괴유출량을 산정하고, 이 중 가장 극한조건에 대한 하류부 홍수추적을 통해 하류부 주요지점별 첨두유량, 최고홍수위, 홍수파 도달시간, 최고홍수위 도달시간을 산정하고 최고홍수위와 좌 우 제방고도 비교한다. 그리고 이러한 하천수리해석 결과를 GIS를 연계하여 수심별 홍수범람지도를 작성하는 방법에 관해 상세하게 보여준다. 본 연구에서 제안한 홍수범람지도 작성방법은 홍수터 해석에 대해 1차원 하천수리해석 모형이 가지는 한계점을 보완할 수 있다. Flooding as one of the major natural disasters affects country`s economy. Most country is establishing a flood inundation maps as a non-structural measures to prevent damages from an abnormal flooding over the design criteria of hydraulic structures such as dams, storages, and levees et al. This study suggests method to establish GIS based inundation map induced by dam-break flood simulated by 1D hydrodynamic model(DAMBRK). In this study, the dam-break hydrograph were simulated by various scenario events and especially for the extreme event, peak discharge, peak water surface elevation, arrival time of flood wave and peak water surface elevation are calculated by flood routing at the control points and peak water surface elevation was compared with levee height to detect inundation. In addition, the detailed flood inundation mapping processes at each water level linking with GIS are presented in this study. The proposed method to establish a flood inundation map is able to complement the limitation of 1D hydrodynamic model in analyses of flood plains.

원전기기 내진검증 기술

김병현,Kim, Byeong-Hyeon 재료연구소 1997 機械와 材料 Vol.9 No.4