• Architectural research
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• 제19권3호
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• pp.63-70
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• 2017

The purpose of this study was to examine the effect of housing units assembled as complexes on residential satisfaction. Two analyses were performed to examine residential satisfaction of Multi-Family Housing Blocks (MFHB; complex) and Multi-Household Housing (MH; non-complex). The residents from both housing types were surveyed on nine categories of questions regarding residential satisfaction and one on overall satisfaction from their experiences. First, the t-test results between MFHB and MH suggest that MFHB has insufficient effect in terms of improvement over MH, as their satisfaction differences are either insignificant or uncontrollable. Second, the common factors affecting Overall Satisfaction of MFHB and MH are Maintenance and Residential Environments.

• Journal of the Korean Data and Information Science Society
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• 제18권4호
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• pp.1033-1043
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• 2007

The multi layer perceptron for segmenting objects in images only uses the input windows that are made from a image in a fixed size. These windows are recognized so each independent learning data that they make the performance of the multi layer perceptron poor. The poor performance is caused by not considering the position information and effect of input windows in input images. So we propose a new approach to add the position information and effect of input windows to the multi layer perceptron#s input layer. Our new approach improves the performance as well as the learning time in the multi layer perceptron. In our experiment, we can find our new algorithm good.

• 한국기계가공학회지
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• 제18권10호
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• pp.93-98
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• 2019

Recently, with the development of the aerospace and automotive industries, the demand for high-melting-point materials has increased. However, high-melting-point materials are difficult to cut through conventional machining methods. Thermally assisted machining (TAM) is a method for improving the machinability by preheating the materials. A laser, the most commonly used device for TAM, has high efficiency through local preheating but is not sufficient for maintaining a high preheating temperature due to rapid cooling. However, the use of multi-heat sources can supplement the disadvantage of a single heat source. The high preheating temperature can be maintained with a wide and deep heat-affected zone (HAZ) by multi-heat sources. The purpose of this study is to analyze the preheating effects of multi-heat sources using laser plasma. Thermal analysis and preheating experiments were carried out. As a result, the high preheating effect of multi-heat sources compared with a single heat source was verified.

• 대한통합의학회지
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• 제7권2호
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• pp.19-29
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• 2019

Purpose : To determine whether an advanced rehabilitation therapy combined with conventional rehabilitation therapy consisting of sensorimotor exercises that would be superior to a usual treadmill training in gait ability and fall risk in subacute stroke patients. Methods : Thirty subjects randomly assigned to either multi-sensorimotor training group (n=19) or treadmill training group (n=18). Both groups first performed conventional physical therapy for 30 min, after which the multi-sensorimotor training group performed multi-sensorimotor training for 30 min, and the treadmill training group performed treadmill gait training for 30 min. Both groups performed the therapeutic interventions 5 days per week for 8 weeks. Gait ability was evaluated using the GAITRite system and Fall risk was measured using the Biodex Balance system before intervention and after 8 weeks. Results : There were no intergroup differences between demographic and clinical characteristics at baseline (p>.05). Both groups showed a significant improvement in gait ability (p<.05) and Fall risk (p<.05). In particular, the multi-sensorimotor training group showed more significant differences in gait velocity (p=.05), step length (p=.01) and stride length (p=.014) than the treadmill training group. Conclusion : The multi-sensorimotor training program performed on multiple types of sensory input had beneficial effect on gait ability. A large-scale randomized controlled study is needed to prove the effect of this training.

• 한국지하수토양환경학회지:지하수토양환경
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• 제25권4호
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• pp.58-66
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• 2020

Since the typical horn-type ultrasonic equipment induces a reaction at the probe tip, the sonochemical reaction has a limitation that it occurs only in a specific area. As one of the ways to overcome this limitation, an ultrasonic device with multi-stepped horn equipped with several oscillators has been developed. The objective of this study was to investigate the sonochemical effects induced by acoustic cavitation system in 20 kHz multi-stepped ultrasonic horn using calorimetry, KI dosimetry and the luminol test. The sonochemical effects of multi-stepped ultrasonic horn were compared with that of the typical horn-type 20 kHz ultrasonic device. The effect of immersion depth and power on the sonochemical reaction was investigated in the ultrasonic system with multi-stepped ultrasonic horn. Higher calorimetric energy was obtained at higher immersion depth and power conditions. Sonochemical effects increased significantly when using the high immersion depth and input power. However, as the input power increased, the cavitation reaction zone concentrated around the ultrasonic horn. Additionally, the experiments to examine the effect of liquid temperature was conducted. The smaller sonochemical reaction was obtained for the higher liquid temperature. The effect on temperature seems to be closely related to liquid conditions such as viscosity and vapor pressure of water.

• 농업과학연구
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• 제46권1호
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• pp.1-10
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• 2019

The objective of this study was to determine the effect of multi-enzyme supplementation in a corn and soybean meal-based diet on the growth performance, apparent nutrient digestibility, blood profile, fecal microbes and noxious gas emission in growing pigs. A total of 80 crossbred [(Landrace ${\times}$ Yorkshire) ${\times}$ Duroc] growing pigs with an average body weight (BW) of $25.04{\pm}1.44kg$ were used in a 6-week experiment. The experimental treatments were as follows: CON, basal diet and; T1, basal diet + 100 mg/kg multi-enzyme. During the experiment, the pigs fed the diet with multi-enzyme supplementation had a higher gain to feed ratio (G/F) (p < 0.05) than the pigs fed the diet without multi-enzyme supplementation. On day 42, the pigs fed the diet with multi-enzyme supplementation had decreased $H_2S$ and $NH_3$ emissions (p < 0.05) than the pigs fed the diet without multi-enzyme supplementation. However, no effect was observed on nutrient digestibility, blood profiles and fecal microbes among the treatments (p > 0.05). In conclusion, it is suggested that multi-enzyme supplementation in a corn and soybean meal based diet can partly improve the growth performance and noxious gas emission of growing pigs.

• Bulletin of the Korean Chemical Society
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• 제30권1호
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• pp.124-128
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• 2009

In this study, the effect of multi-step purification or functionalization on physicochemical properties of multi-walled carbon nanotubes (MWNTs)/epoxy (EP) nanocomposites was investigated. The nanocomposites containing multi-step purified MWNTs showed a stronger influence on $T_g$ and increased in mechanical properties in comparison to nanocomposites containing the same amount of only purified MWNTs. Consequently, the multi-step purification of MWNTs led to an improvement of thermomechanical properties of nanocomposites, resulting from improving the intermolecular interaction of MWNTs in epoxy matrix resins.

• 한국콘텐츠학회논문지
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• 제9권8호
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• pp.73-83
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• 2009

현재 인터넷에서 사용 중인 연결지향형 트랜스포트 계층 프로토콜은 TCP이다. TCP는 단일 경로 상에서 단일 스트림을 이용하여 통신하기 때문에, 경로상의 링크가 다운되는 경우 통신 불가능이라는 결함을 지니고 있다. 새로운 트랜스포트 계층 프로토콜인 SCTP는 두 개 이상의 경로를 제공하는 멀티호밍(multi-homing) 특성을 갖고 있기 때문에 1차 경로 상의 링크가 다운되는 경우 TCP와 달리 대체 경로를 이용하여 통신이 가능하다. 따라서 본 연구에서는 링크다운 환경에서 NS-2 시뮬레이션을 이용하여 SCTP의 멀티호밍 효과를 측정하고 분석하였다. 특히 SCTP는 TCP처럼 싱글호밍으로도 사용될 수 있기 때문에 $SCTP_{single-homing}$과 $SCTP_{multi-homing}$으로 구분하였다. 시뮬레이션에서는, 링크다운 시간, 대역폭, 그리고 RTT(Round Trip Time)를 변화시키면서 TCP와 SCTP의 처리율과 대역폭 이용률을 측정하였다. 링크다운 시간에 따른 비교 결과, $SCTP_{multi-homing}$의 처리율이 TCP의 처리율 보다 평균적으로 18% 우수한 것으로 확인되었다. RTT와 대역폭에 따른 결과는 $SCTP_{multi-homing}$의 처리율이 TCP의 처리율 보다 각각 27%와 9% 우수한 것으보 판명되었다. $SCTP_{single-homing}$과 TCP 사이에는 별다른 성능 차이가 없었다. 종합적으로는 링크다운 환경에서 $SCTP_{multi-homing}$의 성능이 TCP보다 평균 18% 우수하였다. 이 결과는 실제 인터넷 경로 상에서 링크 다운이 발생되는 경우 TCP에 대한 SCTP의 멀티호밍 효과를 추정하기 위한 벤치마크로 사용될 수 있다.

• 디지털콘텐츠학회 논문지
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• 제5권3호
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• pp.187-191
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• 2004

모바일 통신 채널의 빠른 변화는 다중 반송파 변조의 성능에 많은 영향을 준다. 본 논문에서는 다중 반송파 CDMA 네트워크의 BER 성능을 분석하였고 등가 신호 대 전체 잡음 전력비를 라이시안 페이딩, 부분대역간섭 다중접속 사용자 간섭채널에서 유도하였다. MC-CDMA 시스템의 역방향 링크 등가 SNIR을 사용하여 MC-CDMA/BPSK 신호의 성능을 부분대역간섭의 점유율과 간섭 전력에 따라서 평가하였다. 그리고 다중반송파 멀티미디어 시스템의 QoS를 향상하기 위한 부분대역간섭의 영향을 종합적으로 연구하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.670-676
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• 2004

In this paper, a modeling method for the vibration analysis of rotating structures composed of beams and shells employing multi-reference frames is presented. The rotary inertia effect and the geometric stiffening effect that results from centrifugal inertia force we considered for beams and shells with lumped mass model. In most previous studies, single reference frame has been employed for the vibration analysis. In the present study, a modeling method employing multi-reference frames is presented and the effects of employing multi-reference frames on the analysis accuracy are investigated through solving numerical examples.