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101.
A study was made on the structure, adsorption behavior toward fabrics and dependence upon particle size of an aqueous dispersion of di(hydrogenated tallow)dimethyl ammonium chloride (purified Arquad 2HT), the most widely used softener base. From the results of analyses by X-ray diffraction, differential scanning calorimetry (DSC) and electron microscopy, it was found that the dispersed phase of Arquad 2HT dispersion consisted of hydrated particles having a similar structure to that of the multilayered liposomes (or vesicles) of phospholipids and that these particles were adsorbed onto fabrics by softening treatment It was also found that finely dispersed particles showed better softening and antistatic performances in addition to a superior storage stability, due to their higher rate and uniformity of adsorption compared to roughly dispersed particles.  相似文献   
102.
Analysis has shown that vibration cutting is a suitable process for production of internal screw threads in thin stainless steel cylinders. A precision vibration internal threading lathe has been developed. Experiments were carried out with this lathe to investigate the tool life, chip type, accuracy of machined thread etc. The main results obtained by experiments are: (1) the chips formed by this vibration cutting are unoxidized, white-grey, flow type chips; (2) a smooth machined flank is produced which has an iridescent surface; (3) the desired sharp profile of the internal thread can be machined; (4) the relation between tool wear and cutting lengths was investigated; (5) by this process and lathe, it is possible to thread 10 000 pieces per tool. This is a 200-fold extension of tool life, compared with 40–50 pieces in conventional cutting. The vibration internal threading machine has been used in mass production tests, and the above results confirmed on about 500 000 work-pieces.  相似文献   
103.
Evaluation studies in the development of new types of cosmetics are divided into exploratory and confirmatory research. The exploratory evaluation aims to discover the unknown characteristics of tested products, whereas the confirmatory evaluation aims to examine the attainment of their designed quality. This report presents an evaluation method to achieve simultaneously the two objectives using the think-aloud method with the paired comparisons method. The results obtained for two foaming cleansers possessed both exploratory aspects and confirmatory ones, and were straightforward in demonstrating the features of the foaming cleansers, because the think-aloud method was not restricted by a complicated evaluation procedure. The method proposed from the discussions can be readily applied to the process of new product development.  相似文献   
104.
The crystal structures of type-I and type-III clathrate compounds in the Ba–Ga–Ge system have been investigated by synchrotron X-ray powder diffraction at room temperature with single- and split-site models to describe thermal vibration of the Ba atoms that are believed to ‘rattle’ in the encapsulating cages. The split-site model is verified to be more plausible when judged from the changes of the extent of thermal vibration of the Ba atoms and the shape changes of the encapsulating cages with the Ga content for both types of compound. When described with the split-site model, the value of lattice thermal conductivity at room temperature decreases with increasing split distance of the Ba atom site for both types of compound, indicating that the split distance can be used as a parameter to describe the extent of thermal vibration (rattling motion) of the Ba guest atoms in the encapsulating cages.  相似文献   
105.
106.
Recently, broadband networks have made great progress and various interactive visual communication systems including video conferencing, video telephones and video networks for meetings are becoming increasingly popular. However, unnatural eye contact in the displays used by these communication systems has presented a barrier to natural conversation between communicators. We confirmed the possibility of realizing the feeling of eye contact that is part of natural face-to-face conversation. This paper also describes experimental results on the permissible eye-line angle that gives a sense of eye contact and the influence of image resolution.  相似文献   
107.
The applicability of a blackbody source to sensitivity measurements and calibration of an uncooled Terahertz (THz) focal plane array (FPA) is discussed, but the combination of a blackbody source and a band-pass filter may not be suitable for these purposes. Two ways to measure the minimum detectable power (MDP) of uncooled THz-FPAs are described and compared when used with strong THz sources such as a quantum cascade laser (QCL). The MDP is defined as the radiant power that produces a signal-to-noise ratio of unity in the output of a THz imager that uses a THz-FPA operating at a TV frame rate. One method (method 1) is based on the hypothesis that the beam pattern of the THz source is close to a Gaussian pattern. In another method (method 2), the signal level of the background in an image that does not contain a THz source is subtracted from the signal of the image. While method 2 is more flexible, how large the signals coming from THz source should be, as compared with the noise level, remains to be defined. Finally, based on issues with the current non-uniformity correction (NUC) technique, specifications are proposed for THz source power and wobbling technique to obtain uniform illumination for an ideal NUC technique.  相似文献   
108.
A rolling element has a spring characteristic in the transient displacement region from the stationary state to a continuous rolling motion. For this reason, a bearing having a rolling element is useful for constructing an ultra-precision positioning device. In this paper, a mechanism for the damping capacity generation of a rolling element is investigated, to improve the dynamic characteristic of this positioning device. A stage supported by two rollers is constructed, and its tangential displacement is measured accurately when the driving force is acting. As a result, it is confirmed that the rolling element has a nonlinear spring characteristic. Energy loss is generated by the reciprocating motion of the stage in the transient displacement region. This is the main cause of the damping capacity. Furthermore, this energy loss or damping capacity of the stage can be improved by using two rollers with different diameters.  相似文献   
109.
Many pneumatic actuators have been developed to be lightweight with high output for decreasing the impact force. However, for pneumatic actuators it is difficult to maintain exact control because these actuators have constraints. In this study, we developed model predictive control (MPC) that can accommodate these constraints when applied to the pneumatic actuator we developed. As described here, we compared and evaluated the control performance using MPC and proportional–integral–derivative (PID) control with an anti‐windup control system. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
110.
This paper introduces a switching command-based whole-body operation method for humanoid robots. Humanoid robots are biped machines possessing multiple degrees of freedom (DOF). Due to the complexity of their multi-DOF structure, and the difficulty in maintaining postural stability, whole-body operation of humanoid robots is fundamentally different from traditional fixed-base manipulators or stable-base mobile manipulators. By studying the shifts in locus of attention between human body joints during task execution, we developed a switching command-based operation method that allows the operator to select only the necessary points of the humanoid robot's body for manipulation. Whole-body motion satisfying the desired movements of the selected points is generated using an inverse-kinematics motion generation scheme. This switching operation method enables flexible whole-body operation of humanoid robots using simple input devices. The proposed whole-body operation method is implemented as a teleoperation system using two 3-DOF joysticks to operate a 30-DOF humanoid robot (HRP-1S) developed in the Humanoid Robotics Project (HRP) of the Ministry of Economy, Trade, and Industry of Japan. Experiments teleoperating HRP-1S confirmed the effectiveness of our method.  相似文献   
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