• Journal of Broadcast Engineering
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• v.13 no.2
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• pp.188-199
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• 2008

In conventional video coding, encoder complexity is much higher than that of decoder. However, investigations for lightweight encoder to eliminate motion prediction/compensation claiming most complexity in encoder have recently become an important issue. The Wyner-Ziv coding is one of the representative schemes for the problem and, in this scheme, since encoder generates only parity bits of a current frame without performing any type of processes extracting correlation information between frames, it has an extremely simple structure compared to conventional coding techniques. However, in Wyner-Ziv coding, channel decoding errors occur when noisy side information is used in channel decoding process. These channel decoding errors appear more frequently, especially, when there is not enough correlation between frames to generate accurate side information and, as a result, those errors look like Salt & Pepper type noise in the reconstructed frame. Since this noise severely deteriorates subjective video quality even though such noise rarely occurs, previously we proposed a computationally extremely light encoding method based on selective median filter that corrects such noise using spatial correlation of a frame. However, in the previous method, there is a problem that loss of texture from filtering may exceed gain from error correction by the filter for video sequences having complex torture. Therefore, in this paper, we propose an improved lightweight encoding method that minimizes loss of texture detail from filtering by allowing information of texture and that of noise in side information to be utilized by the selective median filter. Our experiments have verified average PSNR gain of up to 0.84dB compared to the previous method.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.7
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• pp.1098-1105
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• 2021

The International Maritime Organization has steadily strengthened environmental regulations on nitrogen oxides and carbon dioxide emitted from marine vessels. Consequently, the demand for electric propulsion vessels based on eco-friendly elements has increased. To this end, research and development has been steadily conducted for various vessels. In electric propulsion systems, a redundancy configuration is typically adopted to increase reliability and facilitate the onboard arrangement. Furthermore, studies have been actively conducted to ensure the safety of electric propulsion systems through the combination with digital twin technology. A digital twin can be used to predict outcomes in advance by implementing real-world equipment or space in a virtual world like twins, integrating real-world information and data with the virtual world, and performing computer simulations of situations that can occur in a real environment. In this study, we perform failure modes and effects analysis (FMEA) to validate the electric power management system (PMS) redundancy scheme for the digital twin technology development of electric propulsion vessels. Then, we propose the role and algorithm of PMS as a compensation function for preventing primary and secondary damages caused by a single equipment failure of the PMS and preventing additional damages by analyzing the impact on the entire system under real vessel operating conditions based on the redundancy FMEA suggested for the ship classification and certification. We verified the improvement in propulsion conservation through tests.

• Journal of Environmental Health Sciences
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• v.43 no.1
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• pp.1-22
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• 2017

'The worstest environment disaster', 'World's first biocide massacre', 'Home-based Sewol ferry disaster' are all phrases attached to the recent humidifier disinfectant disaster. In the spring of 2011, four of 8 pregnant women including 1 adult man passed away at a university hospital in Seoul due to breathing failure. Epidemiologic investigation conducted by the Korean CDC soon revealed the inhalation of humidifier disinfectant, which had been widely used in Korea during the winter, to be responsible for the disease. As well as lung fibrosis hardening of the lungs, other diseases including asthma, rhinitis, skin disease, liver disease, fetal disease or cancers have been researched for their relation with exposure to the products. By February 9, 2017, 5,342 cases had registered for health problems and 1,131 of them were already dead (20.8% mortality rate). Based on studies by government agencies and a telephone survey of the general population by Seoul National University and civic groups, around 20% of the general public of Korea has used these products. Since the market release of the first product by SK Chemical in 1994, over 7.1 million items from around 20 brands were sold up to 2011. Most of the products were manufactured by well-known large conglomerates such as SK, Lotte, Samsung, Shinsegye, LG, and GS, as well as some European companies including UK-based Reckitt Benckiser and TESCO, the German firm Henkel, the Danish firm KeTox, and an Irish company. Even though this disaster was unveiled in 2011 by the Korean government, the issue of the victims was neglected for over five years. In 2016, an unexpected but intensive investigation by prosecutors found that Reckitt Benckiser manipulated and concealed animal tests for its own brand and brought several university experts and company employees to court. The matter was an intense social issue in Korea from May to June with a surge in media coverage. The prosecutor's investigation and a nationwide boycott campaign organized by victims and environmental groups against Reckitt Benckiser, whose product had been used by more than 70% of victims, led to the producer's official apology and a compensation scheme. A legislative investigation organized after the April 2016 national election revealed the producers' faults and the government's responsibility, but failed to meet expectations. A special law for the victims passed the National Assembly in January 2017 and a punitive system together with a massive environmental epidemiology investigation are expected to be the only solutions for this tragedy. Sciences of medicine, toxicology and environmental health have provided decisive evidence so far, but for the remaining problems the perspectives of social sciences such as sociology and jurisprudence are highly necessary, similar to with the Minamata disease and Wonjin Rayon events. It may not be easy to follow this issue using unfamiliar terminology from medical and chemical science and the long, complicated history of the event. For these reasons the author has attempted to write this article in a question and answer format to render it easier to follow. The 17 questions are: Q1 What is humidifier disinfectant? Q2 What kind of health problems are caused by humidifier disinfectant? Q3 How many victims are there? Q4 What is the analysis of the 1,112 cases of death? Q5 What is the problem with the government's diagnostic criteria and the solution? Q6 Who made what brands? Q7 Has there been a recall? What is still on sale? Q8 Was safety not checked by any producers? Q9 What are the government's responsibilities? Q10 Is it true that these products were sold only in Korea? Q11 Why and how was it unveiled only in 2011 after 17 years of sales? Q12 What delayed the resolution of the victim issue? Q13 What is the background of the prosecutor's investigation in early 2016? Q14 Is it possible to report new victim cases without evidence of product purchase? Q15 What is happening with the victim issue? Q16 How does it compare with the cases of Minamata disease and Wonjin Rayon? Q17 Are there prevention measures and lessons?

• The Korean Journal of Air & Space Law and Policy
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• v.32 no.2
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• pp.33-66
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• 2017

The Korean government enacted the Chapter 6 as of Air Transportation to the Korean Commercial Act, which was enforced in 2011, in order to treat some arguments occurred from air transportation Contracts since air transportations has rapidly increased in Korea. Air transportations has been used more in the field of international market than in the field of domestic market under it's own characteristic. Therefore, many international agreements and protocols related to the air transportations has been appeared from old times and the 1999 Convention for the Unification of Certain Rules for International Carriage by Air ("Montreal Convention") is one of them. The Montreal Convention was adopted in May 28, 1999 at International Conference of Air Law hosted by the International Civil Aviation Organization ("ICAO") in Montreal, Canada where the Headquarter of ICAO is located. The Montreal Convention has been effected from September 5, 2003 and the Korean government ratified the convention in 2007. Therefore, the Montreal Convention came in to force in Korea since 2007. This year, 2017, is the 10th anniversary year since the Montreal Convention has taken effect in Korea. However, there are rare cases that argued the Montreal Convention's scope of application and this Article examines the Korean Supreme Court's case that argued the Convention's scope of application. Thus the Article basically analyzes the case from the perspective of the Montreal Convention's scope of application and examines the Montreal Convention's articles related to the air carrier's liability and extent of compensation for damage that occurred from the international carriage by air. Also this Article analyzes the Korean Commercial Act Chapter 6, which regulated the air carrier's liability and the Article tries to make a comparison between the Montreal Convention and the Korean Commercial Act in order to draw some scheme for the betterment of Korean Commercial Act. It is the hope that the Article contribute to the improvement of Korean Commercial Act through the comparison with the chance of the 10th Anniversary of the Montreal Convention in Korea.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.4
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• pp.1-12
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• 2024

This paper aims to examine the effectiveness of Restricted Stock Units (RSUs) in attracting and retaining top talent for startups and venture companies in the context of their implementation in July 2024. The study investigates whether RSUs align with their original intent and identifies additional measures to enhance their effectiveness. Additionally, the paper explores strategies to actively adopt and revitalize RSUs in the business field from the perspectives of experts representing key market participants within the early-stage startup ecosystem in Korea. The study employs a three-pronged approach. First, a pre-study examines how RSUs overcome the limitations of existing stock compensation schemes, the benefits they offer, and the key conditions for ensuring market-friendly effectiveness. Second, experts involved in the RSU bill's early stages identify five issues that need to be addressed to ensure the bill's market-friendly effectiveness: RSU vesting conditions, RSU vesting targets, RSU vesting scope, RSU vesting timing, and RSU vesting-related tax benefits. Third, the study conducts an FGI with experts representing key market players in the early-stage startup ecosystem to examine the effectiveness and activation measures of the proposed RSU scheme, RSU adoption within the early-stage startup ecosystem minimizing conflict of interests with existing shareholders such as venture capital investor. Finally, experts emphasize the importance of clearly defining and communicating RSU benefits to businesses for effective RSU activation. This study's significance lies in its derivation of various insights from FGI research on the effective adoption and activation of RSUs within the early-stage startup ecosystem. Moreover, it is expected to provide a methodology for gauging opinion-gathering procedures for new bills introduced to foster startup and venture company growth.