• FOCUS: LIFE SCIENCE
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• no.1
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• pp.2.1-2.6
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• 2024

This article provides detailed instructions for the correct installation, maintenance, and troubleshooting of capillary gas chromatography (GC) columns. It emphasizes the importance of proper installation to ensure optimal performance and longevity of the column. The document covers various aspects such as column trimming, installation, conditioning, testing, storage, and ferrule selection. The installation process involves ensuring that the heated zones of the GC are cool before placing the column cage in the column oven. It is essential to avoid sharp bends or stress on the capillary column during installation and to connect the front end of the column into the GC inlet at the recommended insertion distance. The document also provides guidance on trimming the column, including the use of a ceramic wafer or capillary column cutter to achieve a clean, burr-free cut. For previously used columns, it recommends removing any capillary caps, positioning the nut and ferrule, and trimming 1-2 cm from the column. After installation, the column should be purged with carrier gas to remove any oxygen and avoid oxidizing the column. Conditioning the column involves ramping to the upper isothermal temperature limit and maintaining this temperature for a specified duration. It is crucial to maintain carrier gas flow during conditioning and not exceed the upper temperature limit of the column to avoid phase damage. The document also discusses testing column performance using a suitable method and performing a test injection to assess performance. It provides recommendations for column storage, including flame-sealing the capillary ends or using retention gaps for long-term storage. Additionally, it emphasizes the importance of routine maintenance and replacement of GC consumables to extend the column's lifetime. Ferrule selection is another important aspect covered in the article, with a variety of ferrule materials available for different applications. The characteristics of common ferrule options are presented in a table, including temperature limits, reusability, and suitability for specific detector types.

• The Korean Journal of Air & Space Law and Policy
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• v.31 no.1
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• pp.99-144
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• 2016

The summary of the case is as follows: a Korean passenger booked and purchased a business class ticket from Air France that was scheduled to depart from Paris and arrive in Seoul. When the passenger arrived at the check-in counter, he was told that all business class seats were occupied. It was because the flight was overbooked by Air France. The passenger cancelled the Air France flight and took another air carrier. After arriving in Korea, he brought suit against Air France for damages. The purpose of this article is to discuss the governing law when interpreting the contract of international air carriage in accordance with the Korean Private International Act (2001) and to analyze air carrier's civil liability for the bumped passenger in the overbooking case. If the parties have not chosen the applicable law the contract shall be governed by the law of the habitual residence of the consumer in the following situations: prior to the conclusion of the contract, the opposite party of the consumer conducted solicitation of transactions and other occupational or business activities by an advertisement in that country or conducted solicitation of transactions and other occupational or business activities by an advertisement into that country from the areas outside that country and the consumer took all the steps necessary for the conclusion of the contract in that country or in case the opposite party of the consumer received an order of the consumer in that country [Article 27 (1), (2) of the Private International Act]. Since the contract of international carriage falls into the consumer contract, the Supreme Court viewed that the governing law of the contract in this case would be the law of the habitual residence of the consumer (Supreme Court Decision 2013Da8410 decided on Aug. 28, 2014). This interpretation differs from the article 5 (4) of Rome Convention(80/934/EEC) which declares that the consumer contract article shall not apply to neither a contract of carriage nor a contract for the supply of services where the services are to be supplied to the consumer exclusively in a country other than that in which he has his habitual residence. Even though overbooking can be considered as a common industry practice, an air carrier must burden civil liability in case of breach of contract for the involuntary bumped passenger(Seoul Central District Court Decision 2014Na48391 decided on Jan. 29, 2015). In case of involuntary bumping, an air carrier must offer re-routing to passenger's final destination by an alternative flight. If an air carrier fails to effect performance in accordance with the tenor and purport of the obligation, the involuntary bumped passenger may claim damages(Article 390 of the Civil Code).

• Korean journal of communication and information
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• v.42
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• pp.140-167
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• 2008

This study analyzes the legal reasoning of Seoul Central District Court, which imposed legal liability on portals for posting defamatory user replies to news articles, written and provided by the news media, onto their 'News Windows'. Saddling portals with the burden of verifying the facts associated in news articles and imposing the legal obligation as a publisher entail a grave risk of impairment of free flow of information and freedom of expression. Of course, it would ultimately result in tightening up private censorship of information which the Constitution does not allow, and funker keep portals from posting even news articles in which expressed views and opinions are lawful. When judging whether portals should assume liability fur libelous user replies to news articles, it is necessary to distinguish the territory under the direct authority of portals from cafes and bulletin boards managed by third parties. In addition, imposing legal liability above the level of common carrier should be limited to the cases; when portals arbitrarily change the contents of news articles or when the articles portals changed contain libelous contents. Even if those conditions are met, the altered contents should obviously constitute libel. Only in the presence of proof that portals knew the illegality of news articles and did not take proper steps including deleting those replies, should portals not be considered as an accomplice. Nor should portals take responsibility for users' defamatory replies for those reasons.

• Bulletin of the Society of Naval Architects of Korea
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• v.22 no.1
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• pp.45-53
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• 1985

For the analysis of vertical vibrations of a ship's hull, the Timoshenko beam analogy is accepted up to seven or eight-node modes provided that the system parameters are properly calculated. As to the shear coefficient, it has been a common practice to apply the strain energy method or the projected area method. The theoretical objection to the former is that it ignores lateral contraction due to Poisson's ratio, and the latter is of extreme simplifications. Recently, Cowper's and Stephen's shear coefficient formulas have drawn ship vibration analysts' attentions because these formulas, derivation of which are based on an integrations of the equations of three-dimensional elasticity, take Poisson's ratio into account. Providing computer programs for calculation of the shear coefficient of ship sections modeled as thin-walked multicell sections by each of the forementioned methods, the authors calculated natural vibration characteristics of a bulk carrier and of a container ship by the transfer matrix method using shear coefficients obtained by each of the methods, and discussed the results in comparision. The major conclusions resulted from this investigation are as follows: (1) The shear coefficients taking account of the effects of Poisson's ratio, Cowper's $K_c$ and Stephen's $K_s$, result in higher values of about 10% in maximum as compared with the shear coefficient $K_o$ based on the conventional strain energy methods; (a) $K_c/K_o{\cong}1.05\;and\;K_s/K_o{\cong}1.10$ for ships having single skin side-shell such as a bulk carrier. (b) $K_c/K_o{\cong}1.02\;and\;K_s/K_o{\cong}1.05$ for ships having longitudinally through bulkheads and/or double side-shells in the portion of the cargo hod such as a container carrier. (2) The distributions of the effective shear area along the ship's hull based on each of $K_o,\;K_c\;and\;K_s$ are similar each another except the both end portions. (3) Natural frequencies and mode shapes of the hull based on each of $K_c\;and\;K_s$ are of small differences as compared each other. (4) In cases of using $K_c\;or\;K_s$ in ship vibration analysis, it is also desirable to have the bending rigidity be corrected according to the effective breadth concept. And then, natural frequencies and mode shapes calculated with the bending rigidity corrected in the above and with each of $K_o,\;K_c\;and\;K_s$ result in small differences as compared each another. (5) Referring to those mentioned in the above (3) and (4) and to the full-scale experimental results reported by Asmussen et al.[17], and considering laboursome to prepare the computer input data, the following suggestions can safely be made; (a) Use of $K_o$ in ship vibration analysis is appropriate in practical senses. (b) Use of $K_c$ is appropriate even for detailed vibration analysis of a ship's hull. (6) The effective shear area based on the projected area method is acceptable for the two-node mode.

• Journal of Internet Computing and Services
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• v.13 no.6
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• pp.25-32
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• 2012

There is a growing controversy on whether and how to regulate real-time broadcasting services carried on smartphone. Some advocates strict regulation on them but the others minimal regulation. This study aims to suggest guiding rules for how to regulate broadcasting services in smartphone. For this, the study interviewed fourteen (14) executives of broadcasting companies, content providers, policy research center and regulatory body. The analysis indicates that linear channel service in smartphone is similar in form to traditional broadcasting but they should not be regulated at this moment. The supporting reasons are 1) regulating them is technically not effective, 2) they were already regulated in their primary service platforms, 3) they don't have a significant impact on a society. Consequently, the study suggests that the service providers are categorized as value added common carriers as defined in the Telecommunication Business Act.

• Genomics & Informatics
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• v.8 no.1
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• pp.9-18
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• 2010

Integrins are transmembrane receptor proteins that mediate cell-cell adhesion and cell-extracellular matrix (ECM) adhesion. The deregulation of cell-ECM adhesion and the abnormal expression of beta1 (${\beta}1$) integrins (ITGB1s) are involved in tumor development and metastasis. In the liver, the expression of integrins and ECM proteins can be a cause of hepatocellular carcinoma (HCC) development. We performed direct DNA sequencing of 24 individuals, and identified 23 sequence variants of ITGB1 polymorphisms. Among these 23 variants, 7 common variants were selected based on frequencies and linkage disequilibrium, and then genotyped in a larger-scale group of subjects (n=1,103). The genetic associations of ITGB1 polymorphisms with the clearance of HBV and HCC outcome of HBV patients were analyzed using logistic regression models and Cox relative hazard models. Although there was no significant association observed between the polymorphisms and the HCC outcome of HBV patients, the second most common haplotype (ITGB1 haplotype-2 [C-C-C-C-T-C-T]) was putatively associated with HBV clearance (OR=0.75, p=0.008 and $P^{corr}=0.05$). The minor allele frequency (MAF) of ITGB1 haplotype -2 of the spontaneously recovered (SR) group was significantly higher than that of the chronic carrier group (CC) (freq. = 0.248 vs. 0.199). The information derived from this study could be valuable for understanding the genetic factors involved in the clearance of HBV.

• Korean Journal of Veterinary Research
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• v.41 no.1
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• pp.73-78
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• 2001

Yersinia enterocolitica is an inhabitant in the lower intestinal tract of many domestic and wild animals as well as in the nature. Of the several forms of diseases caused by Y. enterocolitica, an acute enteritis, especially in young children, is the most common form. Infection of the bacteria usually occurs through fecal-oral route by contaminated foods or water, especially mountainspring water. Of the domestic animals, swine has been known as one of the most important carrier in the human infection. Based on the knowledge, prevalence of antibody against Y enterocolitica was investigated with swine sera collected from Korea for the survey of Y enterocolitica infection in swine. As the first step of this survey, we analyzed outer membrane protein (OMP) profiles of the representative strains of Y enterocolitica isolated from the feces of piglets and mountainspring water in Korea. Thirty-eight kDa OMP was identified as the common OMP regardless of origin, serotype, or biotype of Y enterocolitica isolates. Presence of antibody specific for 38 kDa OMP of Y enterocolitica in 1,076 swine sera collected from November 1999 to October 2000 was analysed with ELISA. Antibody titer in sows was significantly higher than that in piglets, growing pigs and finishing pigs (p<0.05). Also, there was seasonal difference in the prevalence of antibody against Y enterocolitica. These results would provide the basic knowledge for controlling the Y enterocolitica infection in human as well as swine.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.48.4-48.4
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• 2019

We studied the metal-distribution of isolated Milky-way mass galaxy using various hydrodynamic solvers and investigated the difference of the result between AMR and SPH codes. In particle-based codes, physical quantities like mass or metallicity defined in each particle are conserved unless being injected explicitly by the effect of the supernova, whereas in the Eulerian codes the diffusion is simply accomplished by hydro-equation. Therefore, without including explicit physics of diffusion on the SPH- codes, the metal mixing in the galaxy or CGM only can be accomplished by the direct motion of the particles, however, the standard-SPH codes depress the instability of the turbulent fluid mixing. In this work, we simulated under common initial conditions, common gas-physics like cooling-heating models, and star-formation feedback using ENZO(AMR) GIZMO and GADGET-2 codes. We additionally included a metal-diffusion algorithm on the SPH-codes, which follows the subgrid-turbulent mixing model investigated by Shen et al. (2010) and compared the effect of the metal-outflow on the halo region of the galaxy in different hydro-solvers. We also found that for the implementation of the diffusion scheme in the SPH-codes, the existence of a sufficient number of the gas-particles, which is the carrier of the metals, is necessary. So we tested a new initial condition for proper implementation of the diffusion scheme on the SPH simulations. By comparing the metal-contamination of the circumgalactic medium with different hydrodynamics models, we quantify the diffusion strength of AMR codes using diffusion parameterization of the SPH codes and also suggest the calibration solutions in the different behavior of codes in metal-outflow.

• Journal of Positioning, Navigation, and Timing
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• v.12 no.3
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• pp.245-255
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• 2023

Time comparison techniques are necessary for generating and keeping Coordinated Universal Time (UTC) and distributing standard time clocks. Global Navigation Satellite System (GNSS) Common View, GNSS All-in-View, Two-Way Satellite Time and Frequency Transfer (TWSTFT), Very Long Baseline Interferometry (VLBI), optical fiber, and Network Time Protocol (NTP) based methods have been used for time comparison. In these methods, GNSS based time comparison techniques are widely used for time synchronization in critical national infrastructures and in common areas of application such as finance, military, and wireless communication. However, GNSS-based time comparison techniques are vulnerable to jamming or interference environments and it is difficult to respond to GNSS signal disconnection according to the international situation. In response, in this paper, Code-Division Multiple Access (CDMA) based All-to-All TWSTFT operation method is proposed. A software-based simulation platform also was designed for performance analysis in multi-TWSTFT signal environments. Furthermore, code and carrier measurement jitters were calculated in multi-signal environments using the designed simulation platform. By using the technique proposed in this paper, it is anticipated that the TWSTFT-based time comparison method will be used in various fields and satisfy high-performance requirements such as those of a GNSS master station and power plant network reference station.