• Resources Recycling
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• v.32 no.6
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• pp.45-53
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• 2023

This study discussed the trend and future strategy of adsorption technology R&D to effectively recover ammonia emitted from the livestock fields. A proper ammonia adsorbent should incorporate acidic or hydrogen bonding functional groups on the surface, as well as a high specific surface area and a good surface structure appropriate for ammonia adsorption. Activated carbon and minerals such as zeolite have widely been used as ammonia adsorbents, but their adsorption effects are generally low, so any improvement through surface modification should be necessary. For example, incorporation of metal chloride included in a porous adsorbent can promote ammonia adsorption effectiveness. Recently, new types of adsorbents such as MOFs (Metal-Organic Frameworks) and POPs (Porous Organic Polymers) have been developed and utilized. They have shown very high ammonia adsorption capacity because of adjustable and high specific surface area and porosity. In addition, Prussian Blue exhibited high ammonia adsorption and desorption performance and selectivity. This looks relatively advantageous in relation to the recovery of ammonia from livestock waste discharge. In the future, further research should be made to evaluate ammonia adsorption/desorption efficiency and purity using various adsorbents under conditions suitable for livestock sites. Also, effective pre- and/or post-treatment processes should be integrated to maximize ammonia recovery.

• Applied Chemistry for Engineering
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• v.34 no.6
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• pp.590-595
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• 2023

Novel aromatic imine derivatives with yellow were designed and synthesized for their potential application in color filters for image sensors. The synthesized compounds possessed chemical structures using aromatic imine groups. This innovative material was evaluated thoroughly, considering its optical and thermal properties under conditions similar to commercial device manufacturing processes. Following a rigorous performance evaluation, it was found that (E)-3-methyl-4-((3-methyl-5-oxo-1-phenyl-1H-pyrazol-4(5H)-ylidene)methyl)-1-phenyl-1H-pyrazol-5(4H)-one, abbreviated as MOPMPO, exhibited an impressive solubility of 0.5 wt% in propylene glycol monomethyl ether acetate, predominantly utilized as the solvent in the industry. Furthermore, MOPMPO showed exceptional performance as a color filter material for image sensors, having a high decomposition temperature of 290 ℃. These data unequivocally establish MOPMPO as a viable yellow dye additive for coloring materials in image sensor applications.

• Clean Technology
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• v.29 no.4
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• pp.262-271
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• 2023

Globally, the amount of waste plastics has been occurring to environmental problems. As a result, it is necessary to research methods that utilize waste plastic pyrolysis oil (WPPO) produced by pyrolysis. One such method being studied is utilizing WPPO as a naphtha feedstock. In this study, five types of WPPO were analyzed to determine whether they can be used as raw materials for naphtha. Because of their wide boiling point range, the WPPOs were fractionated into light and heavy fractions through vacuum distillation, and the separation and purification techniques were analyzed using GC-VUV to determine the content of paraffin, olefin, and other compounds. All WPPOs showed high olefin content regardless of the source and fraction. Aromatic and paraffin content varied depending on the source, and oxygen and other compounds also varied significantly by source and fraction. In addition, the light fraction showed a carbon distribution similar to that of naphtha, whereas the heavy fraction showed a carbon distribution of C₁₁ ~ C₁₄. In conclusion, additional processes and raw material selection are required to utilize waste plastic pyrolysis oil as a raw material for naphtha.

• Journal of Navigation and Port Research
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• v.46 no.6
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• pp.483-490
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• 2022

Floating LiDAR is a system that provides a new paradigm for wind condition observation, which is essential when creating an offshore wind farm. As it can save time and money, minimize environmental impact, and even reduce backlash from local communities, it is emerging as the industry standard. However, the design and verification of a stable platform is very important, as disturbance factors caused by fluctuations of the buoy affect the reliability of observation data. In Korea, due to the nation's late entry into the technology, a number of foreign equipment manufacturers are dominating the domestic market. The west coast of Korea is a shallow sea environment with a very large tidal difference, so strong currents repeatedly appear depending on the region, and waves of strong energy that differ by season are formed. This paper conducted a study examining buoys suitable for LiDAR operation in the waters of Korea, which have such complex environmental characteristics. In this paper, we will introduce examples of optimized design and verification of ship-type buoys, which were applied first, and derive important concepts that will serve as the basis for the development of various platforms in the future.

• Journal of Sensor Science and Technology
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• v.33 no.1
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• pp.34-39
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• 2024

Energy harvesting technology that converts the wasted energy resources into electrical energy is emerging as a semipermanent power source for self-powered electronics and wireless low-power sensor systems. Among the various energy conversion techniques, flexible piezoelectric energy harvesters (f-PEHs), using materials with piezoelectric effects, have attracted significant interest because they can harvest a small mechanical energy into electrical signals without constraints of time and space in various environments. In this study, we used a flexible piezoelectric composite film fabricated by dispersing BaHf_xTi_(1-x)O₃ (x = 0, 0.01, 0.05, 0.1) piezoelectric powders inside a polymeric matrix to facilitate f-PEHs. The fabricated f-PEH with optimal Hf contents (x = 0.05) generated a maximum output voltage of 0.95 V and current signal of 130 nA with stable electrical/mechanical disabilities under periodically bending deformations. In addition, we demonstrated a cantilever-type f-PEH and investigated its potential as a sensor by characterizing the output performance under mechanical vibrations at various frequencies. This study provides the breakthrough for realizing self-powered energy harvesting and sensing systems by adopting the lead-free piezoelectric composites under vibrational environments.

• Journal of Navigation and Port Research
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• v.47 no.6
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• pp.394-400
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• 2023

Unlike advancements on land, the maritime industry has been slow to embrace new technologies, primarily due to user apprehension toward unproven innovations in the development process. The existing paradigm of technology development, marked by expert-oriented and laboratory-centric test environments, often leads to a stagnation of progress at the research stage, as the applicability of the technology remains uncertain. This study departed from the conventional research system and introduced a novel methodology known as a "living lab." This approach aimed to ensure applicability by actively involving field-oriented users throughout the entire lifecycle of technology development, encompassing planning, development, verification, and evaluation. The presentation of a plan for the construction and operation of such a living lab in this study is expected to contribute to establishing an efficient experimentation system for ships that can reflect user opinions in the future and to secure technology applicability in the maritime field.

• 한국벤처창업학회:학술대회논문집
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• 2024.04a
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• pp.157-160
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• 2024

KAIST는 다수의 성공 창업 사례와 국내 창업생태계에서 기술창업 발생지로 역사적 의미를 이어오고 있다. 최근 KAIST의 교원 창업이 매년 증가하고 있으며 딥테크 분야 창업으로 성장률과 생존율이 매우 높게 나타나 많은 주목을 받고 있다. 국가적으로도 매우 중요한 혁신기술창업 집적지라는 평가를 받고 있다. 대표적인 기업가적 대학인 KAIST는 기술창업 요람이라고 불리며 오랫동안 캠퍼스 창업생태계를 구축해오고 있다. 또한, 대한민국 창업생태계가 발전하면서 창업기업을 가장 많이 배출시킨 기관으로 혁신적인 창업문화를 선도해 오고 있다. 최근 KAIST의 신문화전략 1 Lab 1 Startup 비전을 수립하였고, 과학기술의 우수한 기술력을 바탕으로 연구실 R&D 기술을 혁신창업으로 이어지는 사업화를 위한 변화와 혁신을 주도하고 있다. 신문화전략 이후 몇 년 동안 교원들이 더욱 창업에 많은 관심을 가지기 시작하였고, 실질적으로 KAIST의 혁신 창업기업 수가 증가하였다. 이러한 결과는 신문화 전략 외에도 다양한 교원창업 성공사례 확산, 교원창업 활성화를 위해 제도개선, 아이디어 발굴부터 기술사업화 지원, 자금조달, 비즈니스 모델 고도화, 기술사업화 및 글로벌 창업지원, 창업 인프라를 제공하고 있기 때문이다. 하지만 KAIST의 창업을 한 교수를 대상으로 세부적으로 기술창업 성공 사례와 핵심요인에 대해서 분석한 연구는 매우 부족하다. 이에 본 연구에서는 KAIST에서는 교원창업 분야에서 성공적인 창업기업을 배출되고 있는 현상에 관한 사례, KAIST의 특화된 창업지원프로그램 소개, 교원 창업 성공 사례들이 어떻게 가능한지에 관한 요인과 그 이유를 탐색하고자 한다. 교수 창업 활성화를 위한 규정, 제도, 창업지원프로그램 등에 대해서 분석을 하고자 한다. 그러므로 본 연구에서는 대표성이 있는 KAIST N차(연쇄 창업가) 창업을 한 A 교수의 사례를 중심으로 어떻게 지속해서 창업하고 있는지, 성공 요인이 무엇인지, 어떻게 하면 교원창업이 활성화될 수 있는지 요인들을 파악하고, 연쇄 창업 방법론이 무엇인지 사례조사와 함께 선행연구 문헌 자료 조사, 인터뷰를 중심으로 연구하여 대한민국에서 실질적인 교수창업이 활성화될 수 있는 활성화 모델을 제시하고자 한다. 따라서 본 연구를 통해 교원창업에 있어서 실질적인 애로사항, 현황, 여러 번 인터뷰를 통해 핵심 요인과 원인을 파악하고자 한다. 국가적으로 대학 교원 창업 활성화 모델이 필요한 시점에 실효성이 있고 성과를 창출할 수 있는 활성화 모델을 제시하여 대학의 우수한 연구, 인적 자원을 활용한 혁신 창업 활성화 모델을 새롭게 제시하여 기업가적 대학으로 발전하고 교원들이 적극적으로 창업에 관심을 가지고 성공적인 성과를 창출할 수 있도록 체계를 만들고자 한다. 본 연구에서 제시하는 A교수의 N차(5개 창업) 창업한 사례 연구를 통해 대학 교원들의 혁신창업 활성화를 위한 정책적, 실무적 시사점을 도출하고자 한다.

• Journal of Food Hygiene and Safety
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• v.39 no.3
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• pp.273-280
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• 2024

In this study, the antibacterial activity and mechanisms of bitter orange extract, a natural antibacterial agent, were investigated, with a focus on its potential application in washing water for controlling Salmonella Typhimurium contamination of salad, a ready-to-eat food. The minimum inhibitory concentration (MIC) of bitter orange extract against S. Typhimurium was determined using the broth dilution method. Subsequently, S. Typhimurium was exposed to various concentrations of bitter orange extract (1/16 MIC-2 MIC) and growth curves were measured. Following treatment with bitter orange extract, we investigated its antibacterial mechanism by measuring intracellular reactive oxygen species (ROS) levels, alterations in membrane potential and integrity, and nucleic acid leakage in S. Typhimurium. Additionally, salads artificially contaminated with S. Typhimurium were treated with different concentrations of bitter orange extract using the dipping method for various durations to assess the reduction effect. The MIC of bitter orange extract against S. Typhimurium was 195.313 mg/L, and bacterial growth was completely inhibited at a concentration of 1 MIC. Furthermore, an increase in bitter orange extract concentration correlated with elevated intracellular ROS levels, membrane potential disruption, membrane damage, and nucleic acid release. Importantly, salads treated with bitter orange extract exhibited a significant reduction in S. Typhimurium counts compared to the control, and prolonged treatment times resulted in further reductions in bacterial counts. Bitter orange extract was more effective than sodium hypochlorite and can be used as a safer salad wash. These findings indicate the potential treatment of salads to prevent foodborne illnesses.

• 한국석유지질학회:학술대회논문집
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• autumn
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• pp.28-46
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• 2001

Natural gas is a mixture of hydrocarbon gases and impurities such as nitrogen, hydrogen sulfide, and carbon dioxide and a clean energy producing no pollution materials for combustion. Currently, the demand of the natural gas is rapidly increasing due to worldwide environmental problems. According to Hubbert's study in the past, the natural gas was predicted as rapidly depleted resources, and then the results led to high gas price and limitation of usage during 1980s. Afterward, the study of natural gas resources based on geology identified the additional natural gas resources that were not considered in Hubbert's study. They are unconventional gas, additional resources in the existed reservoirs, and natural gas in deep subsurface areas. Such additional resouces made the future of natural gas bright and pormised low and stable gas price in the future. Deep natural gas is defined as the gas existing at or below 15,000ft$(4,752{\cal}m)$ in depth from the surface. According to the study from the U.S. Geological Survey(USGS) in 1995, 1,412 TCF of technically recoverable natural gas was remained to be discovered or developed in the onshore of United States. A significant part of that resource base, 114 TCF, exists at deep sedimentary basins, and it shows wide distribution with various geological environments. In 1995, the deep gas contributed to $6.7\% of total supply amount of natural gas in the United States and is expected to be $18.7\% by 201.5. However, the development of the deep gas is a high risky business due to expensive investment and high portion of dry holes, although it is developed. Thus, for developing the deep gas economically, it is necessary to overcome many technical challenges. In this paper, for increasing success rate of the deep gas, 1) geologic and compositional characteristics, and production cost have been analyzed according to depth, 2) technical problems related to deep gas production have been summarized, and 3) finally future study areas for increasing application of the deep gas have been suggested. For reference, this paper was written based on the study results from USGS and Gas Research Institute(GRI), for the United States is doing the most active R&D in the deep gas area, and thus, has many reliable data.

• Journal of Technology Innovation
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• v.19 no.1
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• pp.111-144
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• 2011

This study is to confirm the core factors of innovative capabilities and technological entrepreneurship affecting the performance of technology management and business management of small and medium-sized enterprises (SMEs). Through the consideration about the complex natures of technological innovation affecting by multidimensional factors, this study designs the research model that innovative capabilities, the performances of technology and business management are arranged in accordance with the innovation process; input-output-outcome. To meet this research purpose, the hypothesis are set up based on the previous research studies and the research samples are selected from members of the Innovative Business (INNO-BIZ) Association, located in Seoul and Geyonggi province. As a result of regression analysis to the responses gathered from 360 firms, the performance of business management is influenced positively by the technology superiority, market growth and business profitability which are the dominant factors of performance of technology management. In addition, three sub-variables of innovative capabilities such as R&D, strategic planning and learning capability, have positive effects on both the managerial performances. Innovativeness and progressiveness of technological entrepreneurship affect both the performances positively. Moreover, the co-relation between technological entrepreneurship of an innovation leader and innovative capabilities of organizational members are identified. Lastly, technological entrepreneurship has the mediating effect on the path of leading innovative capabilities to the managerial performances. In conclusion, the research results imply that technological innovation-type firms should periodically evaluate the performance of technology management which are the output of technological innovations and the reinvestment for ultimate business success. And improving and developing innovative capabilities and technological entrepreneurship is required to continuously and consistently investing and supporting resources on technological innovations at the firm-and government-level. It is considered that these are the crucial methods for securing the technologically competitive advantage of SMEs with less resources and narrow innovation range.