This article exposes human rights violations committed at Brothers Home in Busan, South Korea in the 1970s and 1980s, identifying their structural causes and discussing Korean society's efforts to address them. From 1975 to 1987, Brothers Home was the largest group residential facility for the homeless, the ill, the disabled, and the poor—a program that was even commended by the Korean government. However, over the years, various human rights abuses led to the death of 657 residents. While these violations remained hidden from public view for almost 25 years, survivors and supporters waged a long battle to bring them to light. Recently, the Truth and Reconciliation Commission investigated and confirmed the human rights violations as state violence. In this essay, the authors assess the significance this case holds for Korean society.

This paper presents a new approach to the management of the environmental map for mobile robots in dynamic environments. The environmental map is built of primitive features, such as lines, points, and even circles, extracted from ambiguous data captured by the robot's sonar sensor ring. The feature map must be managed because the indoor surroundings where mobile robots operate are continuously changing due to nonstationary objects, such as wastebaskets, tables, and people. The features are processed by trimming, division, or removal, depending on the dynamic circumstances. All processing refers to the occupancy probabilities of grid squares generated for the map features. The occupancy probabilities of the squares are updated using the Bayesian updating model with the sonar sensor data. Experimental results demonstrate the validity of the proposed method.

Plasticity in amorphous alloys is associated with strain softening, induced by the creation of additional free volume during deformation. In this paper, the role of free volume, which was a priori in the material, on work softening was investigated. For this, an as-cast Zr-based bulk metallic glass (BMG) was systematically annealed below its glass transition temperature, so as to reduce the free volume content. The bonded-interface indentation technique is used to generate extensively deformed and well defined plastic zones. Nanoindentation was utilized to estimate the hardness of the deformed as well as undeformed regions. The results show that the structural relaxation annealing enhances the hardness and that both the subsurface shear band number density and the plastic zone size decrease with annealing time. The serrations in the nanoindentation load-displacement curves become smoother with structural relaxation. Regardless of the annealing condition, the nanohardness of the deformed regions is ∼12–15% lower, implying that the prior free volume only changes the yield stress (or hardness) but not the relative flow stress (or the extent of strain softening). Statistical distributions of the nanohardness obtained from deformed and undeformed regions have no overlap, suggesting that shear band number density has no influence on the plastic characteristics of the deformed region.

Mobile robots in field environment travel not only on even terrain but also on uneven or sloped terrain. Practical methods for preventing turnover of the mobile robot are essential since the turnover of the mobile robot is very perilous. This paper proposes an efficient algorithm for preventing turnover of a mobile robot on uneven terrain by controlling linear acceleration and rotational velocity of the mobile robot. The concept of the modified zero moment point (ZMP) is proposed for evaluating the potential turnover of the mobile robot. Also, the turnover stability indices for linear acceleration and rotational velocity are defined with the modified ZMP. The turnover stability space (TSS) with turnover stability indices is presented to control the mobile robot in order to avoid turnover effectively. Finally, the feasibility and effectiveness of the proposed algorithm are verified through simulations conducted on a three-wheeled mobile robot.

Ba5Nb4O15 has shown excellent microwave dielectric properties and is under consideration as a low-temperature cofired ceramic material for advanced radio frequency (RF) applications. By combining tape casting and liquid phase upon sintering, sintered Ba5Nb4O15 thick films stacked to form laminates were produced with aligned elongated grains. This texture engineering, correlated with crystallographic orientation, provides remarkably high temperature stability of dielectric constant up to microwave frequency. Crystallographic texture arises in Ba5Nb4O15 induced by the primary consolidation process, hot pressing, and pulsed laser deposition. The dielectric anisotropy could be efficiently obtained in the textured samples, thereby enabling significant feasibility of microwave circuit designs.

We analyse the performance of a material handling system consisting of two carousels and one picker. We derive expressions for the system throughput and picker utilization. We work out the throughput and picker utilization for two different pick-time distributions: deterministic, which might be a reasonable model when a robot is picking, and exponential, which might be a reasonable model when a person is picking.

We report successful application of a low-temperature-grown amorphous GaAs (a-GaAs) layer for stabilization of the fundamental transverse mode of InGaAs/GaAs vertical-cavity surface-emitting lasers. The maximum currents maintaining a stable fundamental transverse mode were increased by the antiguide effect of a-GaAs with a high refractive index. For 10-μm- and 15-μm-diameter devices, we attained a stable single-mode emission over a wide range of current. The antiguiding of transverse modes in vertical cavity buried in the high refractive cladding layer was calculated using a two-dimensional beam propagation method.

We have fabricated a poly-Si TFT with double gate insulator composed of ECR oxide and APCVD oxide to improved the performance of poly-Si TFTs. The poly-Si TFT with double gate oxide exhibits the remarkable enhancement of the electrical parameters compared with the conventional poly-Si TFTs which has APCVD gate oxide, such as improvement of the subthreshold swing and the low threshold voltage. The proposed poly-Si TFT has a higher oxide breakdown electrical field and the device characteristics are not degraded significantly after an electrical stress. It is found that the ECR oxide plays a key role to improve the device performances and prevent the poly-Si TFTs from degradation due to the electrical stress.

Correlations between the strains induced by a unipolar-electric field and the strains induced by a bipolar-electric field were investigated for Pb(Mg1/3Nb2/3)O3 (PMN) and 0.9{Pb(Mg1/3Nb2/3)O3}-0.1PbTiO3 (0.9PMN- 0.1PT) relaxor ferroelectric ceramics in the temperature range of −50°C ∼ 150°C. The magnitudes of the unipolarly induced-strains are almost the same as the differences between the bipolarly induced-strains and the residual strains, which were attributed to the absence of change of spontaneous polarization direction when the unipolar-electric field is applied.