• Journal of the Korean Geographical Society
• /
• v.42 no.3 s.120
• /
• pp.368-387
• /
• 2007

In order to explain geomorphological characteristics of the Korean Peninsula, it is necessary to understand the spatial distribution of tectonic movements and its causes. Even though geomorphological elements which might have been formed by tectonic movements(e.g. tilted overall landform, erosion surface, river terrace, marine terraces, etc.) have long been considered as main geomorphological research topics in Korea, the knowledge on the spatial distribution of tectonic movement is still limited. This research aims to identify the spatial distributions of tectonic movement via sequential analyses of Digital Elevation Model(DEM). This paper first developed a set of terrain analysis techniques derived from theoretical interrelationships between tectonic uplifts and landsurface denudation processes. The terrain analyses used in this research assume that elevations along major drainage basin divides might preserve original landsurfaces(psuedo-landsuface) that were formed by tectonic movement with relatively little influence by denudation processes. Psuedo-landsurfaces derived from a DEM show clear spatial distribution patterns with distinct directional alignments. Lines connecting psuedo-landsufaces in a certain direction are defined as psuedo-landsurface axes, which are again categorized into two groups: the first is uplift psuedo-landsurface axes that indicate the axis of landmass uplift; and the second is denudational psuedo-landsurface axes that cross step-shaped pusedo-landsurfaces formed via surface denudation. In total, 13 axes of pusedo-landsurface are identified in the Korean Peninsula, which show distinct direction, length, and relative uplift rate. Judging from the distribution of psudo-landsurfaces and their axes, it is concluded that the Korean Peninsula ran be divided into four tectonic regions, which are named as the Northern Tectonic Region, Center Tectonic Region, Southern Tectonic Region, and East Sea Tectonic Region, respectively. The Northern Tectonic Region had experienced a regional uplift centered at the Kaema plateau, and the rate of uplift gradually decreased toward southern, western and eastern directions. The Center Tectonic Region shows an arch-shaped uplift. Its uplift rate is the highest along the East Sea and the rate decreases towards the Yellow sea. The Southern Tectonic Region shows an asymmetric uplift centered a line connecting Dukyu and Jiri Mountains in the middle of the region. The eastern side of the Southern Regions shows higher uplift rate than that of the western side. The East Sea Tectonic Region includes south-eastern coastal area of the peninsula and Gilju-Myeongchun Jigudae, which shows relatively recent tectonic movements in Korea. Since this research visualizes the spatial heterogeneity of long-term tenonic movement in the Korean peninsula, this would provide valuable basic information on long-term and regional differences of geomorphological evolutionary processes and regional geomorphological differences of the Korean Peninsula.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.31
• /
• pp.3-25
• /
• 2006

This study focus on interest for arrears and filling of the gaps left in Article 78 of CISG. In the case of CISG, Article 78 provides for interest any time a payment under a contract is untimely, but does not specify a particular rate of interest or a method to determine such a rate. This issue did not cause any uncertainty under ULIS, the CISG's antecedent, since Article 83 of ULIS provided for 1%p above the official discount rate in the creditor's country. Lacking any CISG general principle as well as any indication by the very same CISG, one can only conclude that the matter must be deferred to the domestic rule of private international law. Actually, resorting to private international law is not only admissible, but expressly required by Article 7(2). In the interpretation and filling of the gaps left in Article 78, there is a considerable difference of opinion especially amongst commentators on whether the gap is a lacuna praeter legem, i.e., one being governed by, but not expressly settled in the CISG, or whether it is an issue falling outside the scope of application of the CISG, i.e. a lacuna intra legem. The protagonists of the former view lay emphasis on the overall objective of the CISG, namely to create a uniform law, whereas the supporters of the latter view refer to the legislative history of Article 78 as the dominant principle in interpreting Article 78. Some authors believe that the issue of determining the rate of interest is not dealt with by CISG and it is, therefore, governed by the applicable domestic law, which is the subsidiary law applicable to the sales contract, since "no special connecting points seem to have developed for the entitlement to interest." In the light of the relevant case law, it seems correct to conclude that the interest rate is not determined by CISG and that courts normally determine it according to their own rules of private international law. While CISG Article 78 expressly does not deal with this issue, PICC Article 7.4.9 and PECL Article 9.508, on the other hand, set forth a precise method for computing interest. Although a method like the one set by PICC may be useful and may encourage uniformity, it still cannot be used under the CISG. The PICC or PECL formula may, however, be a very good starting point in a de jure condendum analysis when a new Article 78 will be drafted, if an interest rate method will ever be embodied in the text of an international convention.

• The Mathematical Education
• /
• v.61 no.3
• /
• pp.419-439
• /
• 2022

This study is based on Freudenthal's mathmatising process and the didactical phenomenology of linear function concept, I have described and examined the process in which students represent the constant rate of change into tables, graphs and equations and, in this way, how they construct mental objects and essence of the linear function concept. The students used the proportionality as composite units, when they represented the phenomenon with constant rate of change into tables. When representing in graphs, all but one student represented it into a line. There were differences among the students in the level they were using the given conditions, co-variation perspective, and corresponding rules when formulating equations. The students compared the relationship between two variables in a multiplicative way, and under the guidance of teachers they reached to the understanding that its relationship becomes a constant. Moreover, they could construct mental objects of a constant rate of change, understanding the situation where the relationship between time difference and distance difference becomes one value, namely speed. The students had difficulties in connecting the rate of change with the inclination of a line. The students constructed the essence (concept) of linear functions, after building and organizing the image that the rate of change is constant, the graph is linear, and the equation is formulated as y=ax+b (a: inclination, b: intercept).

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.39 no.2
• /
• pp.91-103
• /
• 2002

For massive FPGA based emulator, the interconnection architecture and the transmission method of signals between FPGA's are important elements which decide speed of emulation and extendability of emulator. Existing FPGA-based emulation system is faced the problems of which the emulation speed getting slow drastically as the complexity of circuit increases. In this paper, we proposed a new innovative emulation architecture that has high resource usage rate and makes the fast emulation Possible. The emulator with very unique hierarchical ring topology Presented here has merits to overcome FPGA pin limitation by connecting each FPGA into a set of pipelined rings, and it also makes emulation speed at the tens of MHz at least even at system level where the verification complexity can easily exceed the verification capability of designers.

• Transactions of the Korean hydrogen and new energy society
• /
• v.25 no.3
• /
• pp.311-318
• /
• 2014

Performance degradation of a battery in 20 kWh energy storage system (ESS) under various operating conditions was studied. And energy saving of the ESS was also monitored by connecting with 20 kW photovoltaic (PV). PV-connected ESS saved 5~7% of energy consumption in 2013 compared to that without such system in 2012. As charge-discharge cycle increased, capacity decreased and the performance degradation was glaringly obvious after 40 cycles. And as charge and discharge rate increased, the performance degradation was more serious. After 50 charge-discharge cycles, a lot of degraded product was deposited on the surface of anode and cathode electrodes, and the cathode side was more contaminated. Therefore, in order to maintain the cell performance, it was more important to protect the degradation of the cathode side.

• Journal of Internet Computing and Services
• /
• v.9 no.3
• /
• pp.91-101
• /
• 2008

This paper proposes component-based density propagation for tracking a component-based human body model that comprises components and their flexible links. We divide a human body into six body parts as components - head, body, left arm, right arm, left foot, and right foot - that are most necessary in tracking its movement. Instead of tracking a whole body's silhouette, using component-based density propagation, the proposed method individually tracks each component of various parts of human body through a human body model connecting the components. The proposed human body tracking system has been applied to track movements usee for young children's movement education: balancing, hopping, jumping, walking, turning, bending, and stretching. This proposed system demonstrated the validity and effectiveness of movement tracking by independently detecting each component in the human body model and by acquiring an average 97% of high tracking rate.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.6 no.2
• /
• pp.58-66
• /
• 1997

Ti alloys, with the advantageous tensile strength/density ratio and the chemical stability, have been used widely in the aerospace and chemical engineering industries and their usages are still expanding in various industrial areas. In the automotive industry, because of their superior merits of weight reduction and fuel saving, Ti alloys are expected to be used as various part materials including connecting rods, engine valves, springs and retainers, which are all subjected to the fatigue loads. In this study, using Ti-3A1-2.5V, the effects of temperature and microstructure change on fatigue crack propagation has been investigated. Five different microstructures were tested at the temperatures of room temperature, 20$0^{\circ}C$, 30$0^{\circ}C$ and 40$0^{\circ}C$ under the same frequency 20Hz. Some of the conclusions obtained are as follows: (1)Microstructurally, the morphology of less $\alpha$-phase and finer lamellar structure of $\alpha$ and $\beta$-Ti showed better registance to the fatigue crack propagation. (2)Fatigue crack growth rate increased with test temperature.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38C no.8
• /
• pp.692-698
• /
• 2013

As the mobile marketing through the smartphone has gradually increased, the smartphone application services using the AR marker, QR codes and augmented reality have attracted much attention. Furthermore the outdoor advertising is migrated to LED signage, which brings the visible light wireless communication technologies to the trial for mobile marketing. In this paper we present the implementation of AR marker-based URL access application services through smartphone camera using visible-light wireless communication technologies. We analyze the performance of the implemented system in terms of connection time and success rate.

• Journal of Electrical Engineering and Technology
• /
• v.12 no.5
• /
• pp.1743-1753
• /
• 2017

Since there are multiple random variables in the probabilistic load flow (PLF) calculation of distribution system containing distributed generation (DG) and electric vehicle charging load (EVCL), a Monte Carlo method based on composite sampling method is put forward according to the existing simple random sampling Monte Carlo simulation method (SRS-MCSM) to perform probabilistic assessment analysis of voltage quality of distribution system containing DG and EVCL. This method considers not only the randomness of wind speed and light intensity as well as the uncertainty of basic load and EVCL, but also other stochastic disturbances, such as the failure rate of the transmission line. According to the different characteristics of random factors, different sampling methods are applied. Simulation results on IEEE9 bus system and IEEE34 bus system demonstrates the validity, accuracy, rapidity and practicability of the proposed method. In contrast to the SRS-MCSM, the proposed method is of higher computational efficiency and better simulation accuracy. The variation of nodal voltages for distribution system before and after connecting DG and EVCL is compared and analyzed, especially the voltage fluctuation of the grid-connected point of DG and EVCL.

• Ocean and Polar Research
• /
• v.24 no.4
• /
• pp.331-343
• /
• 2002

The southern tidal flat of Kanghwa Island with an area of approximately $90km^2$ is one of the biggest flats on the west coast of Korea. Surface sediments for sedimentary analyses were sampled at 83 stations in August 1997, September 1999 and August 2000. The very poorly-sorted mud sediments were predominant in the eastern part of the tidal flat, whereas the poorly-sorted sand-mud mixed sediments were dominant in the western part. The area of muddy sediment distribution diminished, but that of sandy mud sediment extended to southeastward tidal flat for three years. In the western part of tidal flat, deposition occurred during the period of spring to summer, whereas erosion occurred in winter. Sediment accumulation rates during three years indicated that the sediments deposited continuously in the eastern part of tidal flat, whereas eroded in the western part of tidal flat. Recently, construction of artificial structures such as new airport, island-connecting bridges and dikes near the tidal flat might change tidal current and river flow pattern. In order to reduce the ecological damage and to preserve tidal-flat environment, it is necessary to Investigate long-term impacts on sedimentary environment and ecology.