• Title/Summary/Keyword: active pressure

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Safety Improvement of Military Primary Lithium Batteries by New Protection Circuit for Low Current System (신규 보호회로 적용을 통한 저전류 장비용 군 리튬전지 안전성 개선)

  • Youn, Seong Gi;Cho, Yu Seup
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.32 no.3
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    • pp.256-261
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    • 2019
  • The use of military lithium batteries in this field accelerates the generation of internal pressure because the active materials, lithium and the electrolyte, react to form sulfur dioxide gas. This also reduces the amount of electrolyte. In this condition, batteries can 'vent' or 'explode' especially when completely discharged. Such venting and explosion can be regarded as a safety accident, as toxic gases and shrapnel are ejected from the batteries which can harm the user. A DTaQ was carried out in 2017 as a quality problem solution project to solve this safety issue. A protection circuit was thereby developed, which included a micro controller unit (MCU) which can stop battery usage when in an over-discharging state by sensing its low-voltage condition. In 2018, this concept was expanded to lithium batteries for the remote controlled ammunition system. This paper reports results of the improved performance.

A Study on the Characteristics of Ni/Ce0.9Gd0.1O2-x and Cu/Ce0.9Gd0.1O2-x Catalysts for Methanol Steam Reforming Synthesized by Solution Combustion Process (용액연소법으로 합성한 Ni/Ce0.9Gd0.1O2-x와 Cu/Ce0.9Gd0.1O2-x 촉매의 메탄올 수증기 개질 특성 연구)

  • LEE, JUNGHUN
    • Journal of Hydrogen and New Energy
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    • v.30 no.3
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    • pp.209-219
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    • 2019
  • Methanol is a liquid fuel which could also be produced from renewable energy sources and has appreciably high energy density. In this work, we investigated the application of $Ce_{0.9}Gd_{0.1}O_{2-x}$ supported Cu and Ni catalysts for hydrogen production via methanol steam reforming. Catalysts were synthesized by solution combustion synthesis. The prepared catalysts with various active materials and Cu loading amounts were tested in a reactor at $200-300^{\circ}C$, 0-5 barg range and steam to methanol molar ratio was 1.5. The catalytic properties of Cu and Ni were compared, and the catalytic performance was shown to depend on the amounts of metal loading and operating conditions such as reaction temperature and pressure.

Long-Term Experiments for Demonstrating Durability of a Concrete Barrier and Gas Generation in a Low-and Intermediate-Level Waste Disposal Facility

  • Kang, Myunggoo;Seo, Myunghwan;Kim, Soo-Gin;Kwon, Ki-Jung;Jung, Haeryong
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.19 no.2
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    • pp.267-270
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    • 2021
  • Long-term experiments have been conducted on two important safety issues: long-term durability of a concrete barrier with the steel reinforcements and gas generation from low-and intermediate-level wastes in an underground research tunnel of a radioactive waste disposal facility. The gas generation and microbial communities were monitored from waste packages (200 L and 320 L) containing simulated dry active wastes. In the concrete experiment, corrosion sensors were installed on the steel reinforcements which were embedded 10 cm below the surface of concrete in a concrete mock-up, and groundwater was fed into the mock-up at a pressure of 2.1 bars to accelerate groundwater infiltration. No clear evidence was observed with respect to corrosion initiation of the steel reinforcement for 4 years of operation. This is attributed to the high integrity and low hydraulic conductivity of the concrete. In the gas generation experiment, significant levels of gas generation were not measured for 4 years. These experiments are expected to be conducted for a period of more than 10 years.

Ameliorative Potential of Rengyolone Against CCI-induced Neuropathic Pain in Rats

  • Lee, Gil-Hyun;Hyun, Kyung-Yae
    • Biomedical Science Letters
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    • v.26 no.4
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    • pp.310-318
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    • 2020
  • The sciatic nerve is the largest nerve among the peripheral nerves, and the damage to the sciatic nerve is caused by mechanical and physical pressure. This is an important disease that consumes a lot of time and money in the treatment process. Among them, research on relieving nerve pain caused by damage to the peripheral sciatic nerve has been made efforts to prevent and treat this disease through various methods such as drugs, natural products, electrical stimulation, exercise therapy, and massage. Existing treatments are not very effective in neurological pain, and countermeasures are needed. Forsythia Fructus, used in this study, has been used as a therapeutic agent for infectious diseases and a pain reliever for cancer from the past, and in past studies, it has been known to properly control the inflammatory response. In this study, rengyolone, a physiologically active substance of Forsythiae Fructus, was administered to rats that caused chronic left nerve pain to verify the pain relief effect. As a result of the experiment, it was found that mechanical pain and cold stimulation pain were significantly reduced in the rengyolone-treated group compared to the non-administered group. In addition, it was found that nerve growth factor (NGF) mRNA expression was significantly reduced and Cyclin-dependent kinase 2 (Cdc2) expression was increased in the rengyolone administration group. This increase in NGF expression is thought to be related to rengyolone's anti-inflammatory regulatory mechanism. It is expected that the reduced NGF was directly involved in pain relief.

A Guideline for Sodium Reduction of Processed Foods (가공식품 나트륨 저감화 가이드라인)

  • Kim, Eui-Su;Yim, Gu-Sang;Choi, Kyung-Sook;Jeong, Gwang-Ho;Lee, Mi-Young;Ryu, Seung-Ho;Yoon, Eun-Kyung
    • Food Science and Industry
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    • v.49 no.2
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    • pp.8-17
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    • 2016
  • Sodium is a component of salt and naturally taken in the process of taking in table salt. For food processing, salt is very important. In general, salt adds flavor and taste including a salty taste and rheologically, it plays an important role in forming tissues. Also, it helps in improving preservability of food by controling growth of microorganisms. But excessive intake of salt has been blamed for outbreak of high blood pressure, heart disease, stroke, osteoporosis, kidney stone, stomach cancer and others. For this reason, there are active efforts to reduce sodium of processed foods all around the world. In Korea, a guideline for sodium reduction in 27 items and 44 kinds of foods including confectionery was suggested as part of the 'processed food sodium reduction guideline development project', which has been conducted since 2012.

Analysis of Endothermic Regenerative Cooling Technologies by Using Hydrocarbon Aviation Fuels (탄화수소 항공유를 이용한 흡열재생냉각 기술분석)

  • Lee, Hyung Ju
    • Journal of the Korean Society of Propulsion Engineers
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    • v.25 no.3
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    • pp.113-126
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    • 2021
  • In order to develop active cooling systems for a hypersonic cruise vehicle, a series of studies need to be preceded on regenerative cooling technologies by using endothermic reaction of liquid hydrocarbon aviation fuels. Among them, it is essential to scrutinize fluid flow/heat transfer/endothermic pyrolysis characteristics of supercritical hydrocarbons in a micro-channel, as well as to acquire thermophysical properties of hydrocarbon fuels in a wide range of temperature and pressure conditions. This study, therefore, reviewed those technologies and analyzed major findings in related research areas which have been carried out worldwide for the development of efficient operational regenerative cooling systems of a hypersonic flight vehicle.

Complex open elbow fracture-dislocation with severe proximal ulna bone loss: a case report of massive osteochondral allograft surgical treatment

  • Concina, Chiara;Crucil, Marina;Theodorakis, Emmanouil;Saggin, Giorgio;Perin, Silvia;Gherlinzoni, Franco
    • Clinics in Shoulder and Elbow
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    • v.24 no.3
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    • pp.183-188
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    • 2021
  • We report a case of a 69-year-old right-dominant man who had an open Monteggia-like lesion of the right elbow (Gustilo-Andersen IIIA) with severe proximal ulna bone loss associated with an ipsilateral ulnar shaft fracture due to a motorcycle accident. The patient underwent two-stage surgery. Wound debridement and bridging external fixation were performed at first. Three months later, a frozen massive osteochondral ulnar allograft was implanted and fixed with a locking compression plate. A superficial wound infection appeared 5 weeks after the second surgery. Superficial wound debridement, negative pressure therapy, and antibiotics were administered for 3 months, achieving infection healing. At 3 years post-surgery, the elbow range of motion was satisfactory with a Disabilities of the Arm, Shoulder and Hand (DASH) score of 16.7. Radiographs and computed tomography scans showed good allograft-bone integration without allograft reabsorption or hardware loosening. Although not complication-free, massive ulna osteochondral allograft implantation can be considered a valid option in cases of open Monteggia-like lesions associated with ulnar shaft fracture and severe bone loss in active patients, whenever osteosynthesis or joint replacement is not a proper solution. This type of bone stock restoration allows for future surgery, if needed.

One-Dimensional MgO Nanostructures with Various Morphologies Grown by Thermal Evaporation Method under Atmospheric Environment (대기 분위기에서 열증발법에 의해 성장된 여러 가지 형상의 일차원 MgO 나노구조)

  • Nam-Woo Kim;Jin-Su Kim;Geun-Hyoung Lee
    • Korean Journal of Materials Research
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    • v.33 no.7
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    • pp.279-284
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    • 2023
  • One-dimensional MgO nanostructures with various morphologies were synthesized by a thermal evaporation method. The synthesis process was carried out in air at atmospheric pressure, which made the process very simple. A mixed powder of magnesium and active carbon was used as the source powder. The morphologies of the MgO nanostructures were changed by varying the growth temperature. When the growth temperature was 700 ℃, untapered nanowires with smooth surfaces were grown. As the temperature increased to 850 ℃, 1,000 ℃ and 1,100 ℃, tapered nanobelts, tapered nanowires and then knotted nanowires were sequentially observed. X-ray diffraction analysis revealed that the MgO nanostructures had a cubic crystallographic structure. Energy dispersive X-ray analysis showed that the nanostructures were composed of Mg and O elements, indicating high purity MgO nanostructures. Fourier transform infrared spectra peaks showed the characteristic absorption of MgO. No catalyst particles were observed at the tips of the one-dimensional nanostructures, which suggested that the one-dimensional nanostructures were grown in a vapor-solid growth mechanism.

Service Quality in the Distribution of Consumer Attitudes, Word of Mouth, and Private University Selection Decisions

  • PURWANTORO;Nurul Zarirah NIZAM
    • Journal of Distribution Science
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    • v.21 no.10
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    • pp.51-61
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    • 2023
  • Purpose: Research focuses on private universities' professional education in a competitive educational environment. Due to increased competition in the higher education industry, private universities are under pressure to improve their marketing strategies and better understand their prospective students. This study intends to investigate how information sources are used and modified by Indonesian university students when making decisions. Research design, data and methodology: This research is a case study in Riau province, which includes active university students registered in the government database. Data was collected using a questionnaire distributed via Google Forms to students at a private university, and 164 students completed the questionnaire. Results: The results show that the influence of technical quality, functional quality, and image cannot affect word of mouth, and technical quality cannot affect consumer attitudes. The results show that the distribution of high service quality and high image will encourage people to share their experiences by word of mouth to build evaluation attachment in college selection. and found that a good campus image has no direct impact on word of mouth. The spread of an excellent campus image only attracts students to evaluate it. The more talk about the distribution of service quality, the higher the decision to choose the service.

Novel Cultivation of six-year-old Korean Ginseng (Panax ginseng) in pot: From Non-Agrochemical Management to Increased Ginsenoside

  • Kyung Ho Hwang;Hyun Gi Kim;Kiyoung Jang;Yong Ju Kim
    • Journal of Ginseng Research
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    • v.48 no.1
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    • pp.98-102
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    • 2024
  • Background: Ginseng (Panax ginseng Meyer) is a perennial plant belonging to the Araliaceae family that is known to have various beneficial effects including improving memory loss and spatial cognitive ability, and anti-cancer and anti-diabetes activity. Its functional benefits also include improving liver function, regulating blood pressure, stress, and providing antioxidant activity. Usually, various agrochemicals are used in cultivating ginseng preventing from many diseases. Methods: FCGP (field cultivated ginseng in pot) was implemented by imitating MCWG (mountain cultivated wild ginseng). Pesticide analysis of pot cultivation was carried out and the contents of bioactive components such as ginsenoside were also analyzed. Results: FCGP ginsenoside content was higher than that of FCG (field cultivated ginseng) and MCWG. FCGP has been shown to have a relatively high antioxidant effect compared with cultivated ginseng. Conclusion: It was confirmed that ginseng can be grown for 6 years without resorting to use of pesticides. In addition, it was confirmed that effective accumulation of physiologically active ingredients such as ginsenoside is possible. Our result represents FCGP is a novel method of pesticide-free ginseng cultivation