안드로이드에서 구현한 개인화 드라마 추천 시스템

황동현 ( Dong-hyun Hwang ),상운범 ( Woon-bum Sang ),왕봉봉 ( Bong-bong Wang ),박두순 ( Doo-soon Park ) 한국정보처리학회 2017 한국정보처리학회 학술대회논문집 Vol.24 No.2

휴대가 간편한 하드웨어의 발달로 인하여 시간과 장소의 제약 없이 스마트 폰으로 드라마를 시청하는 사람이 증가하였다. 또한, 종합편성 채널의 생성으로 인하여 콘텐츠 제작 및 유통시장이 활성화되어 사용자의 수요에 따라 드라마 및 콘텐츠들이 다양해졌다. 이러한 사용자들의 요구를 해결하기 위해본 논문은 방영되었던 많은 드라마 중 사용자의 개인화 요소를 이용하여 협업필터링 하여 사용자들에게 적합한 드라마를 추천해주는 시스템을 안드로이드 환경에서 구현한다.

횡방향 가진이 동축형 분사기 화염반응에 미치는 영향

황동현(Donghyun Hwang),강철웅(Cheolwoong Kang),안규복(Kyubok Ahn) 한국연소학회 2020 KOSCOSYMPOSIUM논문집 Vol.2020 No.9

기체 메탄과 산소를 이용한 동축 와류형 분사기에서 화염구조와 연소불안정 관계

황동현(Donghyun Hwang),박수진(Sujin Bak),안규복(Kyubok Ahn) 한국추진공학회 2018 한국추진공학회 학술대회논문집 Vol.2018 No.5

다양한 탄화수소 연료를 이용한 난류 예혼합 화염에서 화염길이 스케일링

황동현(Donghyun Hwang),왕가흠(Kexin Wang),안규복(Kyubok Ahn) 한국추진공학회 2016 한국추진공학회 학술대회논문집 Vol.2016 No.5

덤프연소기에서 다양한 탄화수소 계열의 연료를 이용한 화염길이 및 화염중심위치 스케일링이 실험적으로 수행되었다. 덤프연소기는 가스터빈엔진과 램제트엔진에 주로 사용된다. 하지만 높은 에너지 밀도로 인해 연소불안정에 취약하며 연소불안정 발생 시 압력섭동 및 유동섭동으로 인해 화염의 길이 및 중심위치가 변한다. 이번 연구는 에틸렌, 에탄, 프로판 그리고 공기를 사용하였다. 또한 불안정한 유동조건을 모사하기 위해 스피커를 사용하였고, 화염이미지는 CH* chemiluminescence 기법을 적용한 ICCD 카메라를 이용해 촬영하였다. 본 연구의 목적은 입구속도, 당량비, 음향가진에 따른 화염길이 및 화염중심위치의 변화를 조사하고 Reynolds, Strouhal, Damkohler 수와 같은 무차원수들과의 상관관계를 조사하였다. Flame length and flame center length scaling using different hydrocarbon fuels in a dump combustors were conducted experimentally. Generally, dump combustor is used gas turbine engines and ramjet engines. However, it has weakness for combustion instabilities because of high density energy and the flame length and flame center length are changed due to pressure and velocity fluctuation under combustion instabilities. In this work, experiments using ethylene, ethane, propane and air were performed. Also, an acoustic driver was used to simulate unstable flow condition and flame images were taken using ICCD camera with a CH* chemiluminescence technique. The objectives were to investigate about the effects of inlet velocity, equivalence ratio, acoustic forcing frequency on flame lengths and flame center lengths and to examine correlation between normalized flame lengths/flame center lengths and the non-dimensional parameters such as Reynolds, Strouhal, Damkohler number.

함평만 조간대 해조류 분포지역의 퇴적 및 저서환경 특성

황동운 ( Dong Woon Hwang ),고병설 ( Byoung Seol Koh ) 한국수산과학회 2012 한국수산과학회지 Vol.45 No.6

To understand the characteristics of sedimentary and benthic environments in habitats of naturally-occurring intertidal benthic macroalgae, various geochemical parameters of sediment (grain size, ignition loss [IL], chemical oxygen demand [COD], and acid volatile sulfur [AVS]) and pore water (temperature, salinity, pH, and nutrients) were measured in the southern intertidal zone of Hampyeong Bay at two month intervals from April to October 2009. Ecological characteristics including the distribution and biomass of benthic macroalgae were also investigated. Benthic macroalgae were distributed below 4 to 5 m depth from mean sea level near the lower portion of the intertidal zone where air exposure time is relatively short. The distribution area and biomass of benthic macroalgae gradually decreased during the study period. The surface sediments in the benthic algal region were mainly composed of finer sediments, such as slightly gravelly mud and mud. The temperature, salinity, pH, and nutrient concentrations (except dissolved inorganic nitrogen) in pore water did not differ in regions with and without benthic macroalgae, whereas the mean grain size and the concentrations of IL, COD, and AVS in sediments were much higher in regions harboring benthic macroalgae. The correlation between mean grain size and IL in sediments displayed two distinct gradients and the slope was much steeper in regions harboring benthic macroalgae, indicating that the content of organic matter in benthic algal region is not solely dependent on mean grain size. Our results indicate that the benthic macroalgae in the southern intertidal zone of Hampyeong Bay play an important role in the accumulation of organic matter in sediment.

“오크노-타스”(ОКНО-ТАСС)에 대한 도상학적 분석

황동하(Hwang, Dong-Ha) 역사학연구소 2015 역사연구 Vol.- No.29

This paper examines the verbal and visual elements of a Anti-German Propaganda “Okno-Tass” in Soviet Union during the Great Patriotic War, 1941~1945, from a iconographic point of view. The visual poster is considered as a multimodal text where meaning is created through a complex interaction between verbal and visual components. This article analyses the differentiation on space and the representation structure. The artists locate german soldiers and Hitler etc. on the canvas. The left is the space of death, defeat, the satanic World, and the evil-Hitler himself, while the right is for life, victory, the good-Soviet army. The upper sides is the victorious, good, sacred, ideal space, but the lower sides is the defeat, the evil, and the real space. The variety of presentation-the sentimental and the sardonic, the naturalistic and the expressionist, the obvious and the sophisticated, the laconic and the heroicmanaged to appeal to every taste and relieve the monotony of wartime privations. The posters themselves are impressive and striking expressions of patriotic fervor and hatred of the enemy. Orchestrated to win over the hearts and minds of the Soviet population and galvanize them in the fight against the invading armies of Fascist Germany, they celebrated the heroism of the Soviet soldiers; used biting satire to pillory the enemy; fostered a hatred of the Germans and encouraged Soviet troops to greater efforts by depicting Nazi atrocities against women and children; responded to military events; and even acknowledged Soviet collaboration with the allies. Hitler and his henchmen are often shown as rather unpleasant animals—rats, snakes, or spiders. The subjects are harrowing and provide a visual history of one of the most terrible wars in history. Clearly, creative aspirations went hand in hand with the passionate commitment to the Soviet cause.

전완근의 sEMG신호를 이용한 손동작 인식

황동현(Dong-Hyun Hwang),사가영(Ga-Young Sa),김용태(Yong-Tae Kim) 한국지능시스템학회 2016 한국지능시스템학회 학술발표 논문집 Vol.26 No.1

앙드레 지드(Andre Gide)의『소련 방문기(Retour de l’URSS)』에 나타난 소련 인상

황동하 ( Dong Ha Hwang ) 수선사학회 2014 史林 Vol.0 No.49

Andre Gide was more than a writer of fiction who showed an occasional interest in society. He had established himself as an accomplished writer, astute moraliste, and the foremost spokesperson of his generation for personal freedom and self-realization. But beginning in the 1920s, at the peak of his career, Gide became aware, first, that his particular brand of bourgeois individualism was becoming increasingly irrelevant in the contemporary world and, second, that social commitment and even revolution could serve as a powerful source of inspiration and self-renewal. Gide converted to Communism at the beginning of the 1930`s. Over a ten-year period that ended with his public break with the Soviet Union in 1936, Gide as the committed intellectual, interacted with society in what were for him unprecedented ways. As Europe` conscience and “contemporain capital”, Gide is typical of a host of left-wing French intellectuals in the period between the two World Wars. In 1936 he was invited by the Soviet government to visit the country. Like most other progressive intellectuals of his day, Gide was fascinated by the Soviet experiment. To Gide the Soviet Union at first held out the promise of peace and justice for all. Moreover, the Soviet Union alone appeared willing and able to withstand the Fascist menace that consumed much of Europe in the 1930s. But the Soviet Union did not live up to the high expectations of intellectuals in the West. Stalin`s regime had quelled the hopes of the October Revolution. Gide denounced Stalinism in two famous travelogues, Retour de l`USSR and Retouches a mon Retour de l’USSR. He saw the reappearance of social strata, of a kind of aristocracy, inequality, conformism etc in the Soviet Union. To Gide the Soviet Union was counter-revolutionary. The Soviet Union betrayed the ideas of October Revolution.

선형적 밝기의 비균일 양자화에 기반한 그림자 검출

황동국(Dong-Guk Hwang),박종천(Jong-Cheon Park),전병민(Byoung-Min Jun) 한국엔터테인먼트산업학회 2008 한국엔터테인먼트산업학회 학술대회 논문집 Vol.2 No.1

그림자는 물체와 빛의 관계에 의해 생성되는 현상으로 객체를 분할 또는 추출할 경우 객체와 함께 또는 독립된 객체로 분할되거나 추출됨으로 장애요인이다. 따라서 본 논문은 임의의 자연영상에서 그림자의 선형적 밝기 변화를 이용하여 그림자를 효과적 검출하기 위해 선형의존성(linear dependency)을 높이기 위한 방안으로 비균일 양자화(nonuniform quantization) 기법을 제안한다. 이러한 기법은 기하학 정보, 광원의 종류 및 방위에 독립적일 수 있다. 먼저, 잡음제거를 위해 색불변모델(color invariant model)을 이용하여 밝기를 추출하고 메디언필터를 적용한 후 공리에 기반한 임계화로 후보영상을 검출한다. 다음으로, 유사 밝기를 대표 밝기로 표현하는 양자화를 수행한다. 이는 그림자 밝기의 선형의존성을 높이기 위함이다. 마지막으로, 그림자 밝기의 선형적 변화 특성에 따라 랭크(rank)를 이용하여 그림자를 검출한다. 임의의 단일 자연영상의 실험에서, 제안한 알고리즘은 본영과 단색 배경을 갖는 반영 및 셀프그림자의 검출에 강건함을 보였다.

제어방법에 따른 비 반전 벅-부스트 컨버터 효율비교

황동현(Dong-Hyeon Hwang),이우철(Woo-Cheol Lee) 한국조명·전기설비학회 2017 조명·전기설비학회논문지 Vol.31 No.1

A non-inverting buck-boost converter is used to keep the output voltage constant if the range of variation of the input voltage is lower or higher than the desired output voltage. It has a wide input/output voltage range and the output voltage is not inverted unlike a typical buck-boost converter. The non-inverting buck-boost converter is classified into continuous current mode, discontinuous current mode, and critical conduction mode depending on the inductor current. The losses of the switching device depends on the current modes and the efficiency of converter is also different. Therefore, in this paper, the converter is controlled by the fixed frequency method and the critical conduction mode method to compare the converter efficiency according to the current modes at low power. In each control method, the losses of the switching element were calculated and compared. Simulation and experiment were performed to confirm the calculated results.