• 제목/요약/키워드: State Orientation

검색결과 410건 처리시간 0.028초

Nonholonomic 이동로봇의 호밍과 장애물 회피 알고리즘 (A Homing and Obstacle Avoidance Algorithm for Nonholonomic Mobile Robots)

  • 공성학;서일홍
    • 대한전기학회논문지:시스템및제어부문D
    • /
    • 제51권12호
    • /
    • pp.583-595
    • /
    • 2002
  • Homing operation can be defined as a series of actions which are necessary for a mobile robot to move from the current position with any arbitrary orientation to a desired position with a specified orientation, while avoiding possible obstacles. In this paper, a homing and obstacle avoidance algorithm for nonholonomic mobile robots is proposed. The proposed algorithm consists of a local goal generator, a discrete state controller, and local path tracking controller based on Aicardi's path following algorithm. In the discrete state controller, 4 states are defined according to the environmental conditions and 4 desired high-level command for the states are given as follows: avoid, wander, home and homing zones. The proposed local goal generator is designed to generate the desired local path by using weighted distance transforms which are newly made to satisfy the nonholonomic constraints of mobile robots. Here, subgoals are also found as vertices of the desired local path. To demonstrate result effectiveness and applicability of the proposed algorithm, computer simulations are illustrated and experimental results for a real mobile robot system are also provided.

Computational Design of Electrode Networks for Preferentially Aligned Short Fiber Composite Component Fabrication via Dielectrophoresis

  • Srisawadi, Sasitorn;Cormier, Denis R.;Harrysson, Ola L.A.;Modak, Sayantan
    • International Journal of CAD/CAM
    • /
    • 제12권1호
    • /
    • pp.20-28
    • /
    • 2012
  • Finite Element Analysis (FEA) is often used to identify local stress/strain concentrations where a component is likely to fail. In order to reduce the degree of strain concentration, component thickness can be increased in those regions, or a stronger material can be used. In short fiber reinforced composite materials, strength and stiffness can be increased through proper fiber alignment. The field-aided microtailoring (FAiMTa) process is one promising method for doing this. FAiMTa uses principles of dielectrophoresis to preferentially align particles or fibers within a matrix. To achieve the preferred fiber orientation, an interdigitated electrode network must be integrated into the mold halves which can be fabricated by additive manufacturing (AM) processes. However, the process of determining the preferred fiber arrangements and electrode locations can be very challenging. This paper presents algorithms to semi-automate the interdigitated electrode design process. The algorithm has been implemented in the Solidworks CAD system and is demonstrated in this paper.

아아크방전 유도형 이온플레이팅에 의한 Cr-N 피막의 특성 (Properties of Cr-N Films Prepared by the Arc-induced Ion Plating)

  • 정재인;문종호;홍재화;강정수;이영백
    • 한국표면공학회지
    • /
    • 제24권1호
    • /
    • pp.24-24
    • /
    • 1991
  • Cr-N films were deposited on low-carbon steel sheets by the reactive arc-induced ion plating (AIIP). The influence of the deposition conditions (nitrogen pressure and substrate bias voltage) on the crystal orientation, morphology and microhardness of the Cr-N films has been investigated using x-ray diffractometer and scanning electron microscope. The impurities and contaminations on the surface and at the interface, and the layer-by-layer compositions of the film have been analyzed using scanning Auger multiprobe (SAM) and glow discharge spectroscope (GDS). The mixed state of Cr and Cr2N turned out to have a fine fibrous structure. The Cr2N films were deposited at a wide range of nitrogen flow rates. The orientations of Cr2N films were mainly (110) and (111), and the intensity of the (111) peak increased as the substrate bias voltage increased. The micorstructure of the Cr2N film was dense and no columnar structure was observed. The films in the mixed state of Cr2N and CrN were also dense without columnar structure. The maximum microhardness of the Cr-N films was 2400 kg/$\textrm{mm}^2$ at 10gf load.

아아크방전 유도형 이온플레이팅에 의한 Cr-N 피막의 특성 (Properties of Cr-N Films Prepared by the Arc-induced Ion Plating)

  • 정재인;문종호;홍재화;강정수;이영백
    • 한국표면공학회지
    • /
    • 제25권1호
    • /
    • pp.24-33
    • /
    • 1992
  • Cr-N films were deposited on low-carbon steel sheets by the reactive arc-induced ion plating (AIIP). The influence of the deposition conditions (nitrogen pressure and substrate bias voltage) on the crystal orientation, morphology and microhardness of the Cr-N films has been investigated using x-ray diffractometer and scanning electron microscope. The impurities and contaminations on the surface and at the interface, and the layer-by-layer compositions of the film have been analyzed using scanning Auger multiprobe (SAM) and glow discharge spectroscope (GDS). The mixed state of Cr and Cr₂N turned out to have a fine fibrous structure. The Cr₂N films were deposited at a wide range of nitrogen flow rates. The orientations of Cr₂N films were mainly (110) and (111), and the intensity of the (111) peak increased as the substrate bias voltage increased. The microstructure of the Cr₂N film was dense and no columnar structure was observed. The films in the mixed state of Cr₂N and CrN were also dense without columnar structure. The maximum microhardness of the Cr-N films was 2400 kg/㎟ at 10 gf load.

  • PDF

Preferences for Specific Identity-based Message Type under A Chinese Cultural Background

  • CHEN, Chang;TENG, Zhuoqi;CHOI, Nak-Hwan
    • The Journal of Asian Finance, Economics and Business
    • /
    • 제8권2호
    • /
    • pp.513-522
    • /
    • 2021
  • The current research aims to explore which type of identity-based message can be more persuasive for Chinese consumers to form positive restaurant brand attitude based on their cultural orientation, and to examine the roles of brand objective relevance and psychological power state in the persuasive process. The study employs a 2(identity expression focus: warmth vs. competence) × 2(message description manner: identity-defining vs. identity-referencing) × 2(experienced power state: high vs. low) between-subjects design, and conducts an online survey where 240 Chinese participants in total has responded to the questionnaires. SPSS and AMOS programs have been used to examine the hypotheses. The findings suggest that, first, the warmth-focused messages (identity-defining messages) more positively affected Chinese consumers' object relevance than the competence-focused messages (identity-referencing messages); Second, high power-experienced Chinese consumers rather than low power consumers tend to perceive more object relevance at the warmth self-defining messages; Third, brand object relevance revealed a mediation effect in the process of the warmth-focused messages (identity-defining messages) affecting brand attitude. This research offers new insight into the relationships between consumers' cultural orientation, understandings of power, and identity-based consumer behavior, suggesting marketers should take those social influences and consumer diversities into account when developing the message to persuade consumers.

상사 커뮤니케이션 능력과 혁신행동의 관계에서 자기효능감 및 학습목표지향성의 다중 매개효과 (Multi-Mediation of Self-efficacy and Learning Goal Orientation in the links Superior's Communication Ability and Innovative Behavior)

  • 양창영;지성호;강영순
    • 한국콘텐츠학회논문지
    • /
    • 제15권12호
    • /
    • pp.572-585
    • /
    • 2015
  • 본 연구는 공공기관 및 금융기관 종사자를 대상으로 두 가지 관점에서 수행되었다. 첫째, 상사 커뮤니케이션 능력과 자기효능감 및 학습목표지향성의 인과관계 검증이며, 둘째, 상사 커뮤니케이션 능력과 혁신행동의 관계에서 자기효능감과 학습목표지향성의 다중 매개효과 검증이다. 연구대상은 제주지역에 소재하고 있는 공공기관 및 공기업 종사자와 금융기관 종사자를 선정하였으며, 318명으로부터 획득된 자료를 활용하여 공변량구조분석을 실시하였다. 분석결과 첫째, 상사 커뮤니케이션 능력은 자기효능감과 학습목표지향성을 촉발하는 주요 원인이 되는 것으로 확인되었다. 둘째, 상사 커뮤니케이션 능력과 혁신행동의 관계가 자기효능감과 학습목표지향성에 의해 완전매개 되는 것으로 규명되었다. 본 연구의 시사점으로는 첫째, 상사 커뮤니케이션 능력이 구성원의 자기효능감과 학습목표지향성에 영향을 미치는 주요 변인임이 확인되었으며, 이러한 결과는 커뮤니케이션 연구에 의미 있는 시사점을 제공하고 있다. 둘째, 상사 커뮤니케이션 능력과 혁신행동의 관계에서 자기효능감과 학습목표지향성을 고려할 때, 상사 커뮤니케이션 능력이 혁신행동에 미치는 영향력이 자기효능감과 학습목표지향성에 의해서만 가능한 것으로 확인되었다.

20-30대 남성 소비자들의 의복쇼핑성향과 성역할 정체성에 관한 연구 (Clothing Shopping Orientation and Sex Role Identity of Male Consumers Aged Between 20 and 40)

  • 이윤정
    • 대한가정학회지
    • /
    • 제43권9호
    • /
    • pp.27-40
    • /
    • 2005
  • The purpose of this study was to examine the relationship between male consumers' clothing shopping orientation and sex role identity. Since shopping, especially clothing shopping has been traditionally considered a female job, it was expected that male consumers' sex role identity would influence how they approach the task of clothing shopping. Data were collected through an Internet survey firm from men aged between 20 and 40 years(N=199). The major results are as follows: 1. Based on the six clothing shopping orientation factors identified tv factor analysis, the respondents were categorized into 5 distinct groups: Self-Directed Shoppers, Planners, Brand-Oriented Shoppers, Convenience Shoppers, and Impulsive High-Involvers. 2. Five sex role factors were identified by factor analysis: two masculinity factors (strong and reticent) and three femininity factors(gentle, meticulous, and affable). Among these factors, 'gentle' was considered the most ideal, followed in order by 'strong,' 'meticdous,' 'affable,' and 'reticent.' 3. The results of MANOVA showed that the clothing shopping orientation groups statistically differed in their perceived sex role identity as well as in their ideal sex role identity. Overall, Self-Directed Shoppers and Impulsive High-Involvers scored higher in both perceived masculinity and femininity than the other groups. Convenience Shoppers and Planners were high in femininity but low in masculinity. The Brand-Oriented Shoppers were low in both masculinity and femininity. The results indicate that Korean males who are in their 20s and 30s consider androgyny as a desirable state. In addition, those who are high in androgyny are more likely to be highly involved in clothing shopping.

On Fiber Orientation Characterization of CERP Laminate Layups Using Ultrasonic Azimuthal Scanners

  • Im Kwang-Hee;Hsu, David K.;Sim Jae-Gi;Yang, In-Young;Song, Sung-Jin
    • 비파괴검사학회지
    • /
    • 제23권6호
    • /
    • pp.566-576
    • /
    • 2003
  • Carbon-fiber reinforced plastics (CFRP) composite laminates often possess strong in-plane elastic anisotropy attributable to the fiber orientation and layup sequence. The layup orientation thus greatly influences its properties in a composite laminate. It could result in the part being rejected or discarded if the layup orientation of a ply is misaligned. A nondestructive technique would be very beneficial, which could be used to test the part after curing and to require less time than the optical test. In this paper, ultrasonic scanners were set out for different measurement modalities for acquiring ultrasonic signals as a function of in-plane azimuthal angle. The motorized scanner was built first for making transmission measurements using a pair of normal-incidence shear wave transducers. Another scanner was then built fer the acousto-ultrasonic configuration using contact transducers. A ply-by-ply vector decomposition model has been developed, simplified, and implemented for composite laminates fabricated from unidirectional plies. We have compared the test results with model data. It is found that strong agreement are shown between tests and the model developed in characterizing cured layups of the laminates.

마이크로다공성 코팅된 인접 복수 발열체에 대한 PF5060의 냉각 특성 (Characteristics of Cooling for the Adjacent Double Micro-Porous Coated Surfaces in PE5060)

  • 김태균;김윤호;이규정
    • 대한기계학회논문집B
    • /
    • 제30권7호
    • /
    • pp.646-655
    • /
    • 2006
  • The present research is an experimental study on characteristics of cooling behavior for the adjacent copper blocks with surface roughness or micro-porous coated surface. The experiments were carried out at saturation state or within subcooled states of PF5060. The effects of heater orientation and the intervals between heating surfaces or substrates were investigated under various heat flux conditions. The boiling performance of copper block with micro-porous coated surface was better than that of copper block with surface roughness. It is understood that the bubble sweeping enhances boiling performance for the heaters with inclinations of $\theta=45^{\circ}\;and\;\theta=90^{\circ}$, where as the bubble flattening decreases boiling performance for the heaters with inclinations of $\theta=135^{\circ}\;and\;\theta=180^{\circ}$. In comparison to upper heater and below heater with orientation, the upper heater has lower superheat temperature than the below heater due to the bubble sweeping. It is also found that boiling performance decreases in the case of adjacent double heaters with only 0.2cm substrate interval.

Characterization of CFRP Laminates′Layups Using Through-Transmitting Ultrasound Waves

  • Im, Kwang-Hee;David K. Hsu;Cho, Young-Tae;Park, Jae-Woung;Sim, Jae-Ki;Yang, In-Young
    • Journal of Mechanical Science and Technology
    • /
    • 제16권3호
    • /
    • pp.292-301
    • /
    • 2002
  • Ultrasound waves interact strongly with the orientation and sequence of the plies in a layup when propagating in the thickness direction of composite laminates. Also the layup orientation greatly influences its properties in a composite laminate. If the layup orientation of a ply is misaligned, it could result in the part being rejected and discarded. Now, most researchers cut a small coupon from the waste edge and use a microscope to optically verify the ply sequences on important parts. This may add a substantial cost to the production since the test is both labor intensive and performed after the part is cured. A nondestructive technique would be very beneficial, which could be used to test the part after curing and requires less time than the optical test. Therefore we have developed, reduced, and implemented a novel ply-by-ply vector decomposition model for composite laminates fabricated from unidirectional plies. This model decomposes the transmission of a linearly polarized ultrasound wave into orthogonal components through each ply of a laminate. High probability is found, by comparisons between the model and tests, in characterizing cured layups of the laminates by using the proposed method.