• The Korean Journal of Physiology and Pharmacology
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• v.13 no.3
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• pp.215-220
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• 2009

Chlorpheniramine is a potent first-generation histamine $H_1$ receptor antagonist that can increase action potential duration and induce QT prolongation in several animal models. Since block of cardiac human ether-a-go-go-related gene (hERG) channels is one of leading causes of acquired long QT syndrome, we investigated the acute effects of chlorpheniramine on hERG channels to determine the electrophysiological basis for its proarrhythmic potential. We examined the effects of chlorpheniramine on the hERG channels expressed in Xenopus oocytes using two-microelectrode voltage-clamp techniques. Chlorpheniramine induced a concentration-dependent decrease of the current amplitude at the end of the voltage steps and hERG tail currents. The $IC_{50}$ of chlorpheniramine-dependent hERG block in Xenopus oocytes decreased progressively relative to the degree of depolarization. Chlorpheniramine affected the channels in the activated and inactivated states but not in the closed states. The S6 domain mutations Y652A and F656A partially attenuated (Y652A) or abolished (F656A) the hERG current block. These results suggest that the $H_1$ antihistamine, chlorpheniramine is a blocker of the hERG channels, providing a molecular mechanism for the drug-induced arrhythmogenic side effects.

• Journal of Korean Society of Forest Science
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• v.76 no.3
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• pp.275-294
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• 1987

In the United States, forest administration is a constantly changing complex of policies, programs, and management regulations. Forest administration is the product of a brief but tumultuous history during which much of the forests which once covered half the land were coutover for farms, industry, and cities. In the last 15 years, forest administration has been increasingly dominated by concerns for maintaining an ecological balance. Current forest administration is deeply rooted in the American traditions of decentralized federalism and free enterprise, yet combines state socialism and private capitalism. The major elements of U.S. forest administration consist of : 1) programs and policies on taxation, professional education and research, and "cooperative forestry", 2) state controls on forest practices for privately owned lands, and of federal policies and regulations for the management of federal lands. The federal Forest Service has played a lead role in developing and implementing national forest policies and programs. Since the end of World War II, the national forests managed by the Forest Service for multiple use have provided and ever growing fraction of domestic timber needs. In the coming decades, cultural and social trends may force a change in management policy on federal land, reducing the importance of timber harvesting in relation to amenity values.

• Journal of the Korean earth science society
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• v.27 no.7
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• pp.730-744
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• 2006

The United States curriculum reform movement has recently started in each area of science education. The initiatives on curriculum reform stem from a notion that the low rate of science curricula offered in schools has been a serious problem. The schools in the United States are not only facing a lack of offerings within science curricula but also low enrollment in science courses, especially in physics, chemistry, and earth science. This trend resulted in low performances on international achievement tests including TIMSS and PISA. This paper introduces the efforts to solve existing problems through curriculum reform; including ChemCom, BioCom, EarthComm, and Active Physics. In this paper, a discussion is presented to show how the curricula can help address the status quo in science education. More specifically, this paper focuses on curriculum reform in high school earth science (EarthComm), providing a closer look at the scope and sequence of the reform movement. EarthComm was chosen because it was released based on the development of the National Science Education Standards (NRC, 1996). Consequently, EarthComm became a curriculum that espoused the visions of the Standards, which has been guiding the reform of the US curriculum. At the end of this paper, two research outcomes of the EarthComm curriculum implementation in schools are discussed in terms of student learning and differences from conventional curricula.

• Journal of KSNVE
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• v.10 no.4
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• pp.610-614
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• 2000

Cellular Automata(CA)s are used as a simple mathematical model to investigate self-organization in statistical mechanics, which are originally introduced by von Neumann and S. Ulam at the end of the 1940s. CAs provide a framework for a large class of discrete models with homogeneous interactions, which are characterized by the following fundamental properties: 1) CAs are dynamical systems in which space and time are discrete. 2) The systems consist of a regular grid of cells. 3) Each cell is characterized by a state taken from a finite set of states and updated synchronously in discrete time steps according to a local, identical interaction rule. 4) The state of a cell is determined by the previous states of a surrounding neighborhood of cells. A cellular automaton has been attracted wide interest in modeling physical phenomena, which are described generally, partial differential equations such as diffusion and wave propagation. This paper describes one and two-dimensional analysis of wave propagation phenomena modeled by CA, where the local interaction rules were derived referring to the Lattice Gas Model reported by Chen et al., and also including finite difference scheme. Modeling processes by using CA are discussed and the simulation results of wave propagation with one wave source are compared with that by finite difference method.

• Journal of Korean Institute of Industrial Engineers
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• v.28 no.3
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• pp.264-273
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• 2002

This paper focuses on disassembly sequencing, which is the problem of determining the optimum disassembly level and the corresponding disassembly sequence for a product at its end-of-life with the objective of maximizing the overall profit. In particular, sequence-dependent operation times, which frequently occur in practice due to tool-changeover, part reorientation, etc, are considered in the parallel disassembly environment. To represent the problem, a modified directed graph of assembly states is suggested as an extension of the existing extended process graph. Based on the directed graph, the problem is transformed into the shortest path problem and formulated as a linear programming model that can be solved straightforwardly with standard techniques. A case study on a photocopier was done and the results are reported.

• Strategy21
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• s.44
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• pp.54-78
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• 2018

The core of the current constitutional amendment pursued by the Abe administration depends on the status of the Japanese Self-Defense Forces, which include the right to engage in war, in the legal and regular military positions. This is an important turning point for the Abe administration, which aims to become a normal country for Japan, and it is a series of steps that followed in the revision of the U.S. and Japan guidelines in 2015 and the overhaul of the security law in 2016. In this paper, we propose building "A navy Attractive to Alliances" as a way to secure Korea's maritime security under the current security environment. The term "attraction" refers to the alliance "first priority" especially in the United States. The way to do this is to transform the paradigm of the ROK-U.S. alliance into a naval hub in the vast seas, which will allow us to strengthen our national defense and even deter threats from neighboring countries. To this end, our navy needs to have a more active approach to U.S. East Asian strategy. If we can convince the United States to be a nation that contributes more to its East Asian strategy, it will only lead to a strengthening of the status of its alliance and expansion of its unilateral support and military capability against Japan, thus minimizing Japan's influence.

• Aerospace Engineering and Technology
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• v.7 no.1
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• pp.91-98
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• 2008

Since the 1st space race between the United States and Soviet Union during the 1960s, we are competing 2nd space race to occupy the Lunar territory. Since the United States announced to construct the Lunar Base by the end of 2020, ED, Japan, and China launched Lunar explorers successfully. Even India is planning to launch a Lunar explorer in 2008. Korean government also announced that the Korea will launch first Lunar explorer in 2020. In this research Lunar mission trajectory design which will be fundamental data for Lunar mission with variable low thrust and Lunar mission trajectory which has a similar mission specification to SMART-1 are presented.

• Bulletin of the Korean Chemical Society
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• v.15 no.8
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• pp.663-669
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• 1994

Decay kinetics of Ga(5s), Ga(5p) and Ga(4d) atoms in Ar were studied by laser induced fluorescence technique. Theground state gallium atoms in the gas phase were generated by pulsed dc discharge of trimethyl gallium and argon mixtures. Both pulsed discharge and YAG-DYE laser system were controlled by a dual channel pulse generator and the delay time between the end of discharge and laser pulses was set 3.0-6.0 ms. The Ga(5s) and Ga(4d) atoms were generated by single photon excitation from the ground state Ga atoms and radiative lifetimes as well as the total quenching rate constants in Ar were obtained from the pressure dependence of the fluorescence decay rates. The Ga(5p) atoms were populated by a two-photon excitation method and the cascade fluorescence from Ga(5s) atoms were analyzed to extract quenching rate constant of Ga(5p) atoms by Ar in addition to radiative lifetimes of Ga(5p) state. The magnitudes of the quenching rate constants by Ar for the low-lying excited states of Ga atoms are 1.6-3$ {\times}10^{-11}cm^3$ molecul$e^{-1}s^{-1}$, which are much larger than those for alkali, alkaline earth and Group 12 metals. Based on the measured rate constants, kinetic simulations were done to assign state-to-state rate constants.

• Journal of Information Technology Services
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• v.22 no.3
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• pp.29-47
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• 2023

With the recent advancement of information and communication technologies such as artificial intelligence, big data, cloud computing, and 5G, data is being produced and digitized in unprecedented amounts. As a result, data has emerged as a critical resource for the future economy, and overseas countries have been revising laws for data protection and utilization. In Korea, the 'Data 3 Act' was revised in 2020 to introduce institutional measures that classify personal information, pseudonymized information, and anonymous information for research, statistics, and preservation of public records. Among them, it is expected to increase the added value of data by combining pseudonymized personal information, and to this end, "the Expert Data Combination Agency" and "the Expert Data Agency" (hereinafter referred to as the Expert Data Processing Agency) system were introduced. In comparison to these domestic systems, we would like to analyze similar overseas systems, and it was recently confirmed that the Vermont government in the United States enacted the first "Data Broker Act" in the United States as a measure to protect personal information held by data brokers. In this study, we aim to compare and analyze the roles and functions of the "Expert Data Processing Agency" and "Data Broker," and to identify differences in designated standards, security measures, etc., in order to present ways to contribute to the activation of the data economy and enhance information protection.

• Journal of English Language & Literature
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• v.58 no.4
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• pp.783-807
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• 2012

This study compares and contrasts Freud's "work of mourning" which mostly appears in his memorable essay "Mourning and Melancholia" and Derrida's theory of mourning which appears in various works such as MEMOIRES for Paul de Man, The Work of Mourning, and others. Freud maintains that the mourner begins to sever emotional ties to the lost object through a labor of memory and eventually completes the work of mourning. It is a "testing of reality" that motivates the mourner to begin to relinquish emotional attachment to the lost object. Derrida, however, challenges Freudian work of mourning by saying that true mourning lies in "respecting the Otherness of the Other." Derrida suggests that Freud's "normal work of mourning" is "unjust betrayal" of the lost object because it "kills" and "devours" the other and thereby makes it part of the self. So he proposes that work of mourning has "to fail in order to succeed": "success fails" and "failure succeeds." There is an enormous, even epistemological, chasm between Freud who states that mourning, "however painful it may be, comes to a spontaneous end" and Derrida who states that "mourning is interminable. Inconsolable. Irreconcilable." and "I mourn Therefore I am." The former is the voice of "testing of reality" and common sense whereas the latter is that of utopian ethical vision. Yet neither seems to get the upper hand and they are kind of forced to maintain an ongoing dialogue with each other, for true mourning seems to lie somewhere in between.