• Journal of ILASS-Korea
• /
• v.21 no.2
• /
• pp.71-77
• /
• 2016

Air pollutants nitrogen oxides are inevitably generated in the combustion reaction. Its amount trend is steadily increasing because the rapid modern industrialization and population growth. For this reason, NOx is controlled to reducing the harmful components in the exhaust gas. So Marine Environment Protection Committee (MEPC) take effect 'Tier I', 'Tier II' of air pollution regulation in 2005 and 2011 respectively. According to NOx emissions are strictly regulated management of the vessel through them. In addition, since 2016 the regulation enter into force in the next step 'Tier III' was confirmed by MEPC 66th committee. It's 80% enhanced emissions limits than the 'Tier I' Alternatively these emission regulation, research is actively being carried out about exhaust gas after-treatment methods through the vessel application of Selective Catalytic Reduction(SCR). Therefore depending on the basic specification of cell density according to the Area velocity, Space velocity, Linear velocity is studied the effects of NOx removal efficiency

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.6 no.6
• /
• pp.915-922
• /
• 2002

This paper presents an implementation of an Remote Examination System on Internet using Java and SWING GUI API. The system is consisted of three parts: generating examination part that is Java application, answering questions part that is Java Applet, reviewing results part that is Java Applet. The first part is implemented with the 2-tier client/server architecture and the last two parts is implemented the 3-tier client/server architecture. Database programming is done using Java JDBC API for database independence and portability. This system can be used the evaluation of lectures, and substituted for pen-and-pencil examinations or adopted to survey applications based on Internet.

• Journal of Information Technology Applications and Management
• /
• v.12 no.2
• /
• pp.79-106
• /
• 2005

This study, by adopting case study methodology, is focused on examining the present state and analyzing the cause of the digital divide, and suggesting policies for bridging the divide, specifically in view of SMEs. We have taken cases of manufacturing companies, visiting and interviewing 18 SMEs in 10 APEC member economies which show sharp difference in usage of ICT. In order to analyze the digital gap among SMEs, we used 5 variables that are composed of computer hardware, computer software, Internet, readiness of ICT, and performance of ICT adoption, while categorizing the cases into low and high tier based on the national ICT index. From a computer hardware perspective, the high tier (0.66) has almost double the number of PC’s per employee, compared with the low tiers (0.34). This gap can be explained by financial availability of low income and high tariff in the developing economies. In the computer software perspective, the SMEs in the low tier had some restrictive use of computer applications such as financial and accounting management and document management, while those in the high tier enjoyed more diversity in the use of applications such as inventory management, sales management, financial and accounting management, procurement management, CRM, and ERP. In view of the readiness of ICT, the difference in ICT infrastructure and financial status between the low and high tier was far wider than any other variables. As a result of ICT adoption, SMEs benefited in view of learning and growth, internal business processes, customer service, and financial affairs. To effectively bridge the digital divide between the low and high tier, actions such as setting up a secondary market of used computers among cooperating developed and developing countries, developing and diffusing good business applications, and building speedy, low-cost telecommunication infrastructures should be taken.

• International Commerce and Information Review
• /
• v.18 no.4
• /
• pp.285-310
• /
• 2016

The purpose of this study empirically verified impact of strategic and operational integration between first-tier supplier and their supplier and strategic and operational integration between first-tier supplier and their buyer on operation performance. In order to achieve our goal, we tested reliability, validity and path coefficient using structural equation modeling-partial least square (SEM-PLS) over 284 first-tier manufacturing suppliers data that Korea Productivity Center (KPC) surveyed in 2013. This study results indicated that operational integration between first-tier supplier and their supplier or buyer has positive impact on production process flexibility. Meanwhile, strategic integration between first-tier supplier and buyer has positive impact on production flexibility. On the other hand, strategic integration between first-tier supplier and supplier has negative impact on production flexibility. And production process flexibility has positive impact on production flexibility. By empirically testing to departmentalize level and scope of supply chain integration, this study has academic and managerial implications from first-tier perspective on.

• Journal of Korean Society of Transportation
• /
• v.31 no.3
• /
• pp.55-64
• /
• 2013

Conventionally, greenhouse gas (GHG) emissions in the transport sector have been estimated using the fuel consumption (i.e. Tier 1 method). However, the GHG emissions on road networks may not be practically estimated using the Tier 1 method because it is not practical to monitor fuel consumption on a road segment. Further, air pollutant emissions on a road may not be estimated efficiently by the Tier 1 method either due to the diverse characteristics of vehicles, such as travel speed, vehicle type, model year, fuel type, etc. Given these conditions, the goal of this study is to propose a Tier 3 level methodology to calculate $CO_2$ and $NO_X$ emissions on inter-regional roads using the information from ITS infrastructure. The methodology may avoid the under-estimation issue caused by the concavity of emission factor curves because the ITS speed or volume information is aggregated by a short time interval. The proposed methodology was applied to 4 road segments as a case study. The results show that the management of heavy vehicles' speed is important to control the $CO_2$ and $NO_X$ emissions on road networks.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.24 no.2
• /
• pp.208-218
• /
• 2014

Objectives: The major objective of this study was to develop and validate a tier 1 exposure model utilizing worker exposure monitoring data and characteristics of worker activities routinely performed at construction sites, in order to estimate worker exposures without sampling. Methods: The Registration, Evaluation, Authorization and Restriction of Chemicals(REACH) system of the European Union(EU) allows the usage of exposure models for anticipating chemical exposure of manufacturing workers and consumers. Several exposure models have been developed such as Advanced REACH Tools(ART). The ART model is based on structured subjective assessment model. Using the same framework, a tier 1 exposure model has been developed. Worker activities at construction sites have been analyzed and modifying factors have been assigned for each activity. Korean Occupational Safety and Health Agency(KOSHA) accrued work exposure monitoring data for the last 10 years, which were retrieved and converted into exposure scores. A separate set of sampling data were collected to validate the developed exposure model. These algorithm have been realized on Excel spreadsheet for convenience and easy access. Results: The correlation coefficient of the developed model between exposure scores and monitoring data was 0.36, which is smaller than those of EU models(0.6~0.7). One of the main reasons explaining the discrepancy is poor description on worker activities in KOSHA database. Conclusions: The developed tier 1 exposure model can help industrial hygienists judge whether or not air sampling is required or not.

• Journal of Bio-Environment Control
• /
• v.32 no.2
• /
• pp.132-138
• /
• 2023

The Gymnocalycium mihanovichii has been an important export item of Korean flower industry for a long time. Although there is a high demand for grafted cactus from overseas, its production for export is limited. In this study, the growth and marketable yield characteristics of Gymnocalycium mihanovichii 'I-Hong' were compared between soil culture and ebb-and-flow hydroponic system with single- or double-tier bench. As a result, hydroponic methods with single-tier bench resulted in higher fresh weight and glove diameter compared to other cultivation methods. In the ebb-and-flow hydroponic system, hydroponic system with double-tier bench of grafted cactus traits has a lower growth rate than other cultivations. However, the hydroponic system with double-tier bench of grafted cactus significantly increased the yield. In conclusion, the yield from hydroponic system with double-tier bench was better than soil cultivation method. Although there were some differences in color depending on the cultivation method, it was considered that there was no difference in appearance of Gymnocalycium mihanovichii 'I-Hong'. Our results suggest the cultivation methods to overcome production constraints, expand their exports, and improve the value-added characteristics of grafted cactus.

• Journal of Climate Change Research
• /
• v.6 no.3
• /
• pp.175-184
• /
• 2015

In this study GC and PAS were used to calculate $N_2O$ concentration of exhaust gas from Wood Chip combustion system. Fuel supplied to the incinerator was collected and analyzed and then the analysis result was used to calculate $N_2O$ emissions. Tier 3 and Tier 4 Method were used to calculate the $N_2O$ emissions. Plant's Specific emission factor of $N_2O$ by Tier 3 Method was 0.35 kg/TJ, while default emission factor of Wood?Wood Waste proposed by 2006 IPCC G/L was 4 kg/TJ. So the $N_2O$ emission factor of this study was 3.65 kg/TJ lower compared to the IPCC G/L. The total emissions calculated by Plant's specific emission factor was 4.22 kg during the measuring period, but by Tier 4 Method it was 7.88 kg. This difference in emissions was caused by the difference of continuous measuring and intermittent sampling. It would be necessary to apply continuous measuring to calculate emissions of $Non-CO_2$ gas whose the density distribution is relatively high. However currently, according to the target management guideline of greenhouse gas and energy, the continuous measuring method to calculate greenhouse gas emission is applied only to $CO_2$. Therefore for reliable greenhouse gas emission calculation it would be necessary to apply continuous measuring to calculate $Non-CO_2$ gas emission.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.8 no.6
• /
• pp.558-567
• /
• 1997

Linear power amplifier modules with high-efficiency have been developed for PCS handy phone. These modules were designed using extracted large-signal models of MESFETs and harmonic balance simulation. The modules are intended for low-tier and high-tier at the operation frequency range of 1750 ~ 1780 MHz. For low-tier module, the output power and $IMD_3$ were 23.2 dBm and 31 dBc, respectively, at power-added efficiency of 34% with the supply drain bias of 3.6 V. For high-tier module, the output power and $IMD_3$ were 272.2 dBm and 31 dBc, respectively, at power-added efficiency of 33% with the supply drain bias of 4.2 V. These linear power amplifier modules are suitable for PCS handy phone.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.4 no.2
• /
• pp.84-96
• /
• 2001

Test data for a naval vessel is massive, expensive and impossible to be retested in a underwater acoustic measurement on the same condition. So, it is very important. In this paper, I mention massive underwater acoustic multimedia database system that was developed to store a long time, manage systematically, supply raw data and analyze data to user in 2-tier structure. Also, I propose 3-tier structure to extend the current database system that can supply multimedia data.