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In addition to the textile industry, unwinding of cable or fiber is used in various fields such as electronics, communication, and guided weapons. The cable released from the package exhibit a complicated behavior, entailing a combination of rotational and translational motion. This causes problems such as entangling and fracture. Therefore, it is necessary to study boundary and adhesion conditions to prevent unwinding failure. In this study, an experimental device for the analysis of cable unwinding was developed, and unwinding behavior was analyzed experimentally under various unwinding conditions. The experimental device comprises a jig for high-speed camera measurements, control device, and cable unwinding device. Cable behavior was analyzed according to the unwinding velocity and the distance between the fiber package and the point where the fiber was released. In addition, unwinding behavior with respect of the tension acting on the cable was analyzed experimentally by applying the adhesive.

The Directed Energy Deposition (DED) method, which utilizes metal powder and a high-powder laser directed at specific locations on a substrate, is employed across various fields for repairing and refurbishing existing parts. In this study, two types of multi-materials were fabricated by depositing materials similar in alloy composition, and dissimilar, respectively, on an SCM440 substrate using the DED method. Unlike similar material, depositing the dissimilar material resulted in a recrystallized fine microstructure in the interlayer region, which enhanced the tensile properties of the multi-layer specimens. The yield strength, tensile strength, and elongation of the multi-layer specimen with similar material were 562 MPa, 787 MPa, and 14%, respectively, while those of the specimen with dissimilar material were significantly higher at 934 MPa, 1016 MPa, and 30%. These results demonstrate that using dissimilar materials, rather than identical or similar compositions, can improve the tensile properties when repairing and refurbishing parts made of SCM440 material.

This paper proposes an optimal button arrangement of a percussion drill bit and its operating condition to improve drilling efficiency. A new evaluation method is introduced for the button arrangement that utilizes the superimposed impact area, blank area, and drilling deviation moment as the quantitative indices to evaluate the impact of buttons on the rock surface. To determine the optimal button arrangement and its operating conditions, a progressive metamodel-based design optimization was conducted using the new evaluation indices as the analysis response, and then the optimal solution was determined through iteration. Consequently, all the button evaluation indices were reduced significantly and the impact areas were distributed uniformly under a specific operating condition. Additionally, the drilling performances of the optimal button arrangement were investigated according to the operating conditions to obtain the maximum drilling performance in terms of the drilling machine operation.

The transient-state unwinding equation of motion for a thin cable can be derived by using Hamilton’s principle for an open system, which can consider the mass change produced by the unwinding velocity in a control volume. In general, most engineering problems can be analyzed in Cartesian, cylindrical, and spherical coordinate systems. In the field of unwinding dynamics, until now, only Cartesian and cylindrical coordinate systems have been used. A spherical coordinate system has not been used because of the complexity of derivatives. Therefore, in this study, the unwinding motion of a thin cable was analyzed using a spherical coordinate system in both water and air, and the results were compared with the results in Cartesian and cylindrical coordinate systems. The unwinding motions in the spherical, Cartesian, and cylindrical coordinate systems were nearly same in both water and air. The error related to the total length was within 0.5% in water, and the error related to the maximum balloon radius was also within 0.5 % in air. Therefore, it can be concluded that it is possible to solve the transient-state unwinding equation of motion in a spherical coordinate system.

Absolute nodal-coordinate formulation is a technique that was developed in 1996 for expressing the large rotation and deformation of a flexible body. It utilizes global slopes without a finite rotation in order to define nodal coordinates. The method has a shortcoming in that the central processing unit time increases because of increases in the degrees of freedom. In particular, when considering the deformation of a cross section, the shortcoming due to the increase in the degrees of freedom becomes clear. Therefore, in the present research, the dimensional equation of motion concerning a two-dimensional shear deformable beam, developed by Omar and Shabana, is converted into a nondimensional equation of motion in order to reduce the central processing unit time. By utilizing an example of a cantilever beam, wherein an exact solution for the static deflection exists, the nondimensional equation of motion was verified. Moreover, by using an example of a free-falling flexible pendulum, the efficiency of the nondimensional equation of motion gained by increasing the number of elements was compared with that of the dimensional equation of motion.

A flexible hose that is unwound along with fiber-optic cables from a mother ship helps prevent interference with the mother ship during the unwinding of the fiber-optic cable. Because the density of fiber-optic cables is close to the fluid density, if there is no flexible hose, the fiber-optic cable is more likely to interfere with the mother ship because of the motion of underwater vehicles or mother ships. Hence, it is necessary to prevent the interference of fiber-optic cables by using flexible hoses made of stainless steel. Flexible hoses unwound as an underwater vehicle moves are coupled to the vehicle by shear pins, and once all flexible hoses are unwound, the underwater vehicle continues to move forward as the pins fracture. Here, a dynamic load applied on the shear pin for connection in the early stages of the unwinding of the flexible hose is an important factor that controls the position, which should be accurately predicted, prior to the motion of the underwater vehicle. Further, it is essential that the shear pin of the connection part be designed to fracture under the selected load so that underwater vehicle can continue to move forward as the pin breaks. In this study, analysis results based on loading information measured in real experiments were compared and verified, and based on the findings, an analytical model that can predict loads applied on the shear pin was developed.

In this paper, a novel calibration method is developed to improve the measurement accuracy of 3-DOF measurement system. The squareness error between three sensors and misalignment error with respect to reference coordinate of machine tool are calibration parameters. To estimate these parameters, reference ball is used and moved in the measuring ranges of 3-DOF measurement system. The relation between calibration parameters, position of reference ball, measured data of sensors are defined using geometric constraint and estimated using least square method. Finally, simulation is done to check the feasibility of developed calibration method. The result of simulation revealed the validation of developed method.

The objective of this study was to determine whether the expressions of the excision cross-complementing (ERCC1), thymidylate synthase (TS) and glutathione S-transferase P1 (GSTP1) are predictive of clinical outcomes in advanced gastric cancer (AGC) patients receiving treatment with adjuvant 5-fluorouracil (5-FU) and cisplatin (FP) chemotherapy. One hundred forty nine patients were included in this study. ERCC1 and GSTP1 expression was correlated significantly with tumor size (p  =  0.040, p  =  0.018, respectively). Stage and positive lymph node ratio were associated independently with disease free survival (DFS) and overall survival (OS). Both ERCC1 and GSTP1 expression had a significant impact on OS (hazard ratio  =  0.069, p  =  0.021). TS expression was not related to DFS and OS.