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This study aims to provide roadmaps for the sustainable development of South Korea's energy system. To this end, this study developed transition scenarios toward renewable energy for both supply and demand. We use “Long-range Energy Alternatives Planning system (LEAP)” Model and a backcasting approach to illustrate pathways to achieve the goals set forth in each of the scenarios. The four scenarios developed are Business-As-Usual (BAU), Moderate Transition Scenario (MTS), Advanced Transition Scenario (ATS), and Visionary Transition Scenario (VTS). The scenarios are defined according to the differences in the level of final energy consumption and renewable energy share by 2050. Analysis shows an increase in the percentage of renewable energy and a decrease in energy demand lead to improved energy security, more jobs in the electricity generation sector, and a decrease in greenhouse gas emissions. The pathways represented by these scenarios can be regarded as strategic targets for the sustainable development of South Korea's energy system. A set of comprehensive and long-term policies will be needed to attain the goals set forth in the scenarios.

This paper proposes the necessity of a walking period in footstep planning and details situations in which it should be considered. An optimization‐based fast footstep planner that takes the walking period into consideration is also presented. This footstep planner comprises three stages. A binary search is first used to determine the walking period. The front stride, side stride, and walking direction are then determined using the modified rapidly‐exploring random tree algorithm. Finally, particle swarm optimization (PSO) is performed to ensure feasibility without departing significantly from the results determined in the two stages. The parameters determined in the previous two stages are optimized together through the PSO. Fast footstep planning is essential for coping with dynamic obstacle environments; however, optimization techniques may require a large computation time. The two stages play an important role in limiting the search space in the PSO. This framework enables fast footstep planning without compromising on the benefits of a continuous optimization approach.

This paper proposes a simple global path planning algorithm using a ray’s feature of straight in nature with a random reflection model. The ray-casting and tracking (RCT) method is designed to solve global single-query path planning problems with fast convergence time. It is a random sampling-based algorithm that reflects rays with the maximum search length, which is a line of sight restricted only by the obstacles blocking the rays. RCT guarantees a competent path that follows an obstacle’s edges like a path generated by a visibility graph (VG). We demonstrated RCT’s superior performance in terms of both convergence time and path length on various environments that have their own features compared to other well-known path planning algorithms such as the A*, rapidly-exploring random trees, and VG.

Previous walking pattern generation methods could generate walking patterns that allow only straight walking on flat and uneven terrain. They were unable to generate modifiable walking patterns whereby the sagittal and lateral step lengths and walking direction can be changed at every footstep. This paper proposes a novel walking pattern generation method to realize modifiable walking of humanoid robots on unknown uneven terrain. The proposed method employs a walking pattern generator based on the 3-D linear inverted pendulum model (LIPM), which enables a humanoid robot to vary its walking patterns at every footstep. A control strategy for walking on unknown uneven terrain is proposed. Virtual spring-damper (VSD) models are used to compensate for the disturbances that occur between the robot and the terrain when the robot walks on uneven terrain with unknown height. In addition, methods for generating the foot and vertical center of mass (COM) of the 3-D LIPM trajectories are developed to realize stable walking on unknown uneven terrain. The proposed method is implemented on a small-sized humanoid robot platform, DARwIn-OP and its effectiveness is demonstrated experimentally.

Bougie or balloon dilation is a good short-term treatment for caustic esophageal strictures, although recurrence after dilation occurs in approximately 30% of these cases. Therefore, long-term treatment options are required in some cases, and endoscopic incisional therapy has been used for patients with an anastomotic stricture in the gastrointestinal tract. A 58-year-old woman presented with severe swallowing difficulty because of a caustic esophageal stricture, which was caused by accidental exposure to anhydrous acetic acid at infancy. She had undergone several previous bougie and balloon dilations but the stricture did not improve. We performed sequential treatment comprising incision with an insulated-tip knife, balloon dilation, and an oral steroid, which resulted in the patient's symptoms markedly improving. Thus, we report this case of an intractable caustic esophageal stricture, which was successfully treated using combined endoscopic sequential treatment.

We propose a fast and robust finite difference method for Merton``s jump diffusion model, which is a partial integro-differential equation. To speed up a computational time, we compute a matrix so that we can calculate the non-local integral term fast by a simple matrix-vector operation. Also, we use non-uniform grids to increase efficiency. We present numerical experiments such as evaluation of the option prices and Greeks to demonstrate a performance of the proposed numerical method. The computational results are in good agreements with the exact solutions of the jump-diffusion model.

Retroperitoneal fibrosis (RPF) is a rare disease characterized by the presence of fibroinflammatory tissue around the abdominal aorta and ureteral entrapment in most cases. Idiopathic RPF is frequently reported in association with autoimmune diseases; however, there have been few reports of idiopathic RPF associated with Hashimoto's thyroiditis. Here, we report a case of idiopathic RPF with Hashimoto's thyroiditis in a patient with a single functioning kidney, which was successfully treated by corticosteroid therapy and transient intraureteral stent insertion with a double-J catheter.

(-)-Hydroxycitrate (HCA) is known to inhibit increasing malonyl CoA concentration during endurance exercise. Furthermore, a short-term administration of HCA enhances endurance exercise performance in mice. Therefore we investigated the short-term administration of HCA on the exercise performance of athletes. Subjects were administered 250 mg of HCA or placebo as a control (CON) for 5 d, after each time performing cycle ergometer exercise at 60% VO2max for 60 min followed by 80% VO2max until exhaustion. Blood was collected and expired gas samples analyzed at rest and every 15 min. The respiratory exchange ratio was significantly lower in the HCA trial than in the CON trial (p < 0.05). Fat oxidation was significantly increased by short-term administration of HCA, and carbohydrate oxidation was significantly decreased (p < 0.05) during exercise, presumably resulting in increasing the cycle ergometer exercise time to exhaustion after 1 h of 60% VO2max exercise (p < 0.05). These results suggest that a short-term administration of HCA enhances endurance performance with increasing fat oxidation, which spares glycogen utilization during moderate intensity exercise in athletes.

SIFT is one of the feature region extraction methods. It is widely used in various fields including object recognition, mosaic object tracking, etc. However, since SIFT requires lots of arithmetic operations, it is not appropriate for real-time use. Therefore, many researchers has been tried to prepare other measures. SIFT using PCA or SURF is one of them. This paper is to study about the real-time CCTV combined system using the local partial image and to suggest the combination and recognition method for frames. Its purpose is to reduce the combination speed of the suggested algorithm compared to the existing one and to enhance the overall recognition rate according to this. Since the existing SIFT algorithm method has a patent and a slow processing speed, in this paper the improved local image regenerating method was used and the speed was raised according to the actual CCTV processing speed. Based on the recognition rate and speed by using the localized image, this paper consisted of realization of overall system and introduction of algorithm, and the comparative evaluation of performance was carried out through the actual experiment. By applying the CCTV operating in real time, the low-cost system was built with Inline System not with each image and this could reduce the physical fatigue of watcher, have an economic effect and could be used by general users easily.

Object recognition technologies using PCA(principal component analysis) recognize objects by deciding representative features of objects in the model image, extracting feature vectors from objects in an image and measuring the distance between them and object representation. Given frequent recognition problems associated with the use of point-to-point distance approach, this study adopted the K-nearest neighbor technique(class-to-class) in which a group of object models of the same class is used as recognition unit for the images inputted on a continual input image. However, we propose the object recognition technique new PCA analysis method that discriminates an object in database even in the case that the variation of illumination in training images exists. Object recognition algorithm proposed here represents more enhanced recognition rate to change of illumination than existing methods.

Cryptococcus neoformans, an encapsulated fungus, is an important opportunistic pathogen that can cause meningitis in im-munocompromised patients. Since patients with cryptococcemia have high mortality, it is essential to make an early diagnosis and promptly initiate antifungal therapy. However, it is often very difficult to differentiate between cryptococcal meningitis and hepatic encephalopathy in patients with liver cirrhosis, and there is delay in making the diagnosis. Therefore, these patients have a particularly grave prognosis and consequently many patients die before culture results become available. In one study, starting antifungal therapy within 48 hours of the blood culture was associated with improved survival, but patients with liver cirrhosis were significantly less likely to receive antifungal therapy within 48 hours compared to those without liver cirrhosis. Recently, the authors experience a case of a 68-year-old woman with liver cirrhosis who presented with fever and a drowsy mental status. She had a previous history of having been admitted for infection-associated hepatic encephlopathy. Cryptococcal meningitis and cryptococcemia were diagnosed by spinal puncture and culture of cerebrospinal fluid. In spite of adequate treatment, the patient developed multi-system organ failure and eventually expired. Herein, we report a case of cryptococcal meningitis mimicking hepatic encephalopathy in a patient with liver cirrhosis.