• 지역연구
• /
• 제39권2호
• /
• pp.47-61
• /
• 2023

주거환경에 대한 만족도는 주거지 선택 및 이주 등에 영향을 미치는 주요인으로, 도시에서의 삶의 질과 직접적으로 연결된다. 최근 온라인 부동산 서비스의 증가로 주거환경에 대한 사람들의 만족도를 쉽게 확인할 수 있으며, 사람들이 평가하는 내용을 바탕으로 주거환경 만족 요인에 대한 분석이 가능하다. 이는 기존에 활용되던 설문조사 등의 방식보다 더 많은 양의 평가를 효율적으로 활용할 수 있음을 의미한다. 본 연구는 서울특별시를 대상으로 온라인 부동산 서비스인 '직방'에서 수집된 약 3만여 건의 아파트 리뷰를 분석에 활용하였다. 리뷰에 포함된 추천 평점을 토대로, 아파트 리뷰를 긍정적, 부정적으로 분류하고, 딥 러닝 기반 자연어 처리 모델인 BERT(Bidirectional Encoder Representations from Transformers)를 사용하여 리뷰를 자동으로 분류하는 모델을 개발하였다. 이후 SHAP(SHAPley Additive exPlanation)를 이용하여 분류에 중요한 역할을 하는 단어 토큰을 도출함으로 주거환경 만족도의 영향요인을 도출하였다. 더 나아가 Word2Vec을 이용하여 관련 키워드를 분석함으로써 주거환경에 대한 만족도 개선을 위한 우선 고려사항을 제시하였다. 본 연구는 거주자의 정성평가 자료인 아파트 리뷰 빅데이터와 딥러닝을 활용하여 주거환경에 대한 만족도를 긍정적, 부정적으로 자동 분류하는 모형을 제안하여 그 영향요인을 도출하는데 의의가 있다. 분석결과는 주거환경 만족도 향상을 위한 기초자료로 활용될 수 있으며 향후 아파트 단지 인근 주거환경 평가, 신규 단지 및 기반시설의 설계 및 평가 등에 활용될 수 있다.

• 한국융합학회논문지
• /
• 제12권6호
• /
• pp.9-16
• /
• 2021

과거 주가 데이터와 금융 관련 빅 데이터를 사용해 머신러닝 기법으로 주식시장을 예측하는 연구는 다양하게 있어 왔지만, HTS와 MTS를 통해 거래가 가능한 주가지수 연동 ETF가 생기면서 주가지수를 예측하는 연구가 최근 주목받고 있다. 본 논문에서는 KOSPI 연동 ETF를 거래할 목적으로 KOSPI의 상승 예측을 위한 머신러닝 모델과 하락예측을 위한 모델을 각각 구현한다. 이들 모델은 매개변수의 그리드 탐색을 통해 최적화 된다. 또한 정밀도를 개선해 ETF 거래 수익률을 높일 수 있도록 개별 모델들을 조합한 하이브리드 머신러닝 모델을 제안한다. 예측 모델의 성능은 정확도와 ETF 거래 수익률에 큰 영향을 미치는 정밀도로 평가된다. 하이브리드 상승 예측 모델의 정확도와 정밀도는 72.1 %와 63.8 %이고 하락 예측 모델은 79.8 %와 64.3 %이다. 하이브리드 하락 예측 모델에서 정밀도는 개별 모델보다 최소 14.3 %, 최대 20.5 % 개선되었다. 테스트 기간에 하이브리드 모델은 하락에서 10.49 %, 상승에서 25.91 %의 ETF 거래 수익률을 보였다. 인버스×2와 레버리지 ETF로 거래하면 수익률을 1.5 ~ 2배로 높일 수 있다. 하락예측 머신러닝 모델에 대한 추가 연구로 수익률을 더 높일 수 있을 것으로 기대한다.

• 한국국방경영분석학회지
• /
• 제5권1호
• /
• pp.137-153
• /
• 1979

The duel is an extreme case of game situations. The duel is of zero-sum type, but a infinite game. This duel situation appears not only in extreme competitive situations such as war, but also in economic situations such as bidding. The study on duel situations started from late 1940's, but considerable contributions have been made in 1960's by Ancker, Restrepo, Yanovskaya, Kimeldorf among others. Specially Kimeldorf recently has made big contribution in developing the theory of the game-theoretic duel. The purpose of this paper is to summarize and systemize the theory of the game-theoretic duel. In the first part, noisy duel situations shall be dealt with, and in the second part, silent duel shall follow. Finally these two situations shall be generalized in the form of continuous firing model.

• Bulletin of the Korean Chemical Society
• /
• 제24권8호
• /
• pp.1102-1106
• /
• 2003

In our previous work we developed the Finite Field method in order to calculate the fifth-order Raman response. The method was applied to calculate various polarization components of the two-dimensional response of liquid $CS_2$. So far, all calculations relied on the dipole-induced dipole. Accurate time-dependent density functional theory calculations have shown that this model has big discrepancies, when molecules are close together as in the liquid. We now report results of investigations on the importance of multipole and electron overlap effects on the polarizability and the fifth-order Raman response. It is shown that these collision effects, especially the induced multipoles, are crucial in the description of the fifth-order response. The impact is found to be especially pronounced for the χ_{mmzzzz}^{(5)}$response that is solely due to interaction induced effects. The calculated response will be compared with various experimental results.

• 전기의세계
• /
• 제26권5호
• /
• pp.74-82
• /
• 1977

This study is to present a method for reductin of noise and vibration of home electric motors coupled to the mechanical load causing relatively big amplitude of vibration. The noise and vibration factors have been analysed in the divisions such as the pattern related to the armature reaction, the pattern related to the circulating current by induction and the other patterns those are affected by a dditive magnetic field and have an effect on mechanical constants. From the systematic mutual relations between the patterns and daping effects, it is possible to derive the fundamental measure for reduction of noise and vibration. Vibration measurements and analysis were carried out in accordance with the planned experimentation and thre object model was chosen randomly from the production line in a factory where home electric machines were mass-produced. Based on the above-mentioned fundamental measure, suppression effects on noise and vibration have been analysed according to the number of slots, the amount of rotor skew and the way the stator winding connection was series or parallel.

• 대한의용생체공학회:의공학회지
• /
• 제30권4호
• /
• pp.288-293
• /
• 2009

This study investigates the relationship of affective style based on EEG asymmetry, personality, and psychological stress on stress. The experiment consists of three sessions: rest state, landscape scene, and horror film tasks. We used a short horror film to evoke stress. We classified affective style of the individual based on EEG alpha asymmetry: negative bias, positive bias and general. The participants in the negative bias group reported higher levels of stress on the neuroticism of the Big 5 model and Cohen's Perceived Stress Scale. These results demonstrate that participants with the propensity for negative affective style have a nervous temperament and are apt to be stressed.

• 한국공작기계학회논문집
• /
• 제17권6호
• /
• pp.56-62
• /
• 2008

An Allium-odorum is difficult material to handle because it is soft and weak mechanically. For bundling work of allium-odorum, we must grip in the bundle shape of unit weight. However it is difficult to grip allium-odorum by hand because the bundle bulk is very big. Especially, in packing work, the bundle shape of allium-odorum package is more important than other vegetables because the sale price depend on the bundle shape. In this paper, we propose bundling mechanism for a rectangular shape, and semi-auto bundling mechanism by a eccentric roller and a triangular link. We carry out mechanical model and analysis respectively using the CATIA V5 and SimDesigner. We have manufactured the prototype of the semi-automatic bundling machine, and got satisfied result through field test. This machine is in the process of commercialization.

• 한국해양공학회:학술대회논문집
• /
• 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
• /
• pp.461-464
• /
• 2006

The caisson of the inner wall type has a weak point that reflecting wave is big. Therefore it has been studied that the research of the decreasing reflecting wave using installation the perforated wall in front of caisson to decrease of that weak point. In this study, we analyzed the characteristic of reflection horizontal and diamond style vertical slit caisson using hydraulic model test. According to the results of experiments, we could confirm that diamond style vertical caisson has a reflection coefficient which has lower than horizontal caisson of the reflection coefficient of 5~10%.

• International Journal of Safety
• /
• 제9권1호
• /
• pp.35-42
• /
• 2010

We measured the concentrations of air pollutants at several residential sites, roadside sites and industrial sites in Iwate Prefecture, Japan. And the concentration distributions of air pollutants were estimated by atmospheric dispersion model using air emissions data. Based on those results, we calculated environmental risk of air pollutants emitted in Iwate Prefecture. As a result, it was found that the surround of factories with high emissions and highly toxic chemicals and the roadsides were high risk area, benzo(a)pyrene, formaldehyde and ozone exceeded the $10^{-5}$ risk level. Moreover, we tried to use "Loss of life expectancy: LLE" for an index to explain those risk to general public intelligibly. The total LLE of the carcinogenic chemicals was about 8.6 hours. Moreover, LLE of ozone was about 9.2 hours. Ozone has a big influence compared with the carcinogenic chemicals.

• 한국정밀공학회지
• /
• 제25권5호
• /
• pp.89-95
• /
• 2008

The Acousto-Optic Tunable Filter (AOTF) is a high-speed full-field monochromator which generates two spectrally filtered light beams with ordinary and extraordinary polarization state. Thus, AOTF is widely used to build full-field spectral imaging system or spectral domain interferometer. However, AOTF has a big problem that the angle of diffracted light changes according to the scanning of wavelength, which makes image shift on CCD plane In this paper, we propose an analytic design of prism system to compensate the image shift. The detailed analysis of light paths in a prism and basic experimental results are presented to verify our proposed compensation method. The experimental results agree with simulation results based on suggested prism model and image shift is minimized at optimal condition. Also, it can be extended to compensate the image shift for ordinary and extraordinary polarized light simultaneously.