• 한국안전학회지
• /
• 제36권5호
• /
• pp.71-78
• /
• 2021

There are regularly planned overhaul periods in thermal power plants, which involve the maintenance of the boiler of the power plants. However, thermal power plants workers are always exposed to risk during overhaul periods owing to the narrow space and significant dust inside the boiler. Therefore, it is essential to develop a safety monitoring system that is suitable for operating in this type of environment. In this study, we developed not only a worker three-dimensional (3D)-location monitoring system that can monitor and record the entry/exit of workers, their 3D-location, and fall accidents but also a method to secure the working environment and operation efficiency. This system comprises of a worker tag, which was equipped with an inertial measurement unit, a barometric pressure sensor, and a Bluetooth low energy (BLE), and the tags were given to each worker. In addition, the location of workers inside the boiler was measured using a pedestrian dead reckoning (PDR) method and BLE beacons. The location data of the workers tag were transmitted to the integrated database (DB) server through a gateway, and to the administrator monitoring system. The performance of the system was demonstrated inside an actual thermal power plant boiler, and the accuracy and reliability of the system were verified through a number of repeated tests. These results provide insights on designing a new system for monitoring enclosed spaces.

• 한국수소및신에너지학회논문집
• /
• 제31권6호
• /
• pp.622-629
• /
• 2020

The performance and cost of electric vehicles (EVs) are much influenced by the performance and service life of the Li-ion battery system. In particular, the cell performance and reliability of Li-ion battery packs are highly dependent on their operating temperature. Therefore, a novel battery thermal management is crucial for Li-ion batteries owing to heat dissipation effects on their performance. Among various types of battery thermal management systems (BTMS'), the phase change material (PCM) based BTMS is considered to be a promising cooling system in terms of guaranteeing the performance and reliability of Li-ion batteries. This work is mainly concerned with the basic research on PCM based BTMS. In this paper, a basic experimental study on PCM based battery cooling system was performed. The main purpose of the present study is to present a comparison of two PCM-based cooling systems (n-Eicosane and n-Docosane) of the unit 18650 battery module. To this end, the simplified PCM-based Li-ion battery module with two 18650 batteries was designed and fabricated. The thermal behavior (such as temperature rise of the battery pack) with various discharge rates (c-rate) was mainly investigated and compared for two types of battery systems employing PCM-based cooling. It is considered that the results obtained from this study provide good fundamental data on screening the appropriate PCMs for future research on PCM based BTMS for EV applications.

• 셀메드
• /
• 제11권1호
• /
• pp.2.1-2.8
• /
• 2021

The clinical condition Amnesia causes difficulty in learning new information and the inability to recall past events. It is primarily concerned with recent memory loss. Majoon-e-Nisyan (MJN) is a polyherbal Unani formulation, present in a semi-solid form. It is widely used potent drug of the Unani System of Medicine (USM) for treating Nisyan (amnesia). In the present study polyherbal Unani formulation, MJN has been studied for its quality control and acute toxicity. Standardization (quality control) of drugs deals with drug identity, drug quality and purity determination. Standardization of MJN had been done as per the Unani pharmacopoeial parameters approved by World Health Organization (WHO) - Pharmacognostical parameters, Physico-chemical parameters, high-performance thin-layer chromatography (HPTLC), microbial load, aflatoxin, and heavy metals. Solvents and chemicals used in the study were of analytical grade and used instrument were calibrated. By conducting an acute oral toxicity study in rats, the safety of MJN was assessed. The limit test method of OECD guideline 425 was followed in the study. Results of standardization and standard operating procedures (SOPs) for preparation of MJN may serve as the standard reference in the future. The data generated in the study for the quality control of MJN proved the quality of formulation and shows that MJN is not toxic in rats following acute dosing up to 2000 mg/kg bw. The data obtained in the paper for MJN may be used as a standard guideline for preparation of the formulation which can save time, cost, and resources for future research endeavours.

• Imaging Science in Dentistry
• /
• 제51권1호
• /
• pp.55-62
• /
• 2021

Purpose: This study evaluated the influence of a metal artifact reduction (MAR) tool in a cone-beam computed tomography (CBCT) device on the diagnosis of vertical root fractures (VRFs) in teeth with different root filling materials. Materials and Methods: Forty-five extracted human premolars were classified into three subgroups; 1) no filling; 2) gutta-percha; and 3) metallic post. CBCT images were acquired using an Orthopantomograph 300 unit with and without a MAR tool. Subsequently, the same teeth were fractured, and new CBCT scans were obtained with and without MAR. Two oral radiologists evaluated the images regarding the presence or absence of VRF. Receiver operating characteristic (ROC) curves and diagnostic tests were performed. Results: The overall area under the curve values were 0.695 for CBCT with MAR and 0.789 for CBCT without MAR. The MAR tool negatively influenced the overall diagnosis of VRFs in all tested subgroups, with lower accuracy (0.45-0.72), sensitivity (0.6-0.67), and specificity (0.23-0.8) than were found for the images without MAR. In the latter group, the accuracy, sensitivity, and specificity values were 0.68-0.77, 0.67-083, and 0.53-087, respectively. However, no significant difference was found between images with and without MAR for the no filling and gutta-percha subgroups (P>0.05). In the metallic post subgroup, CBCT showed a significant difference according to MAR use (P<0.05). Conclusion: The OP 300 MAR tool negatively influenced the detection of VRFs in teeth with no root canal filling, gutta-percha, or metallic posts. Teeth with metallic posts suffered the most from the negative impact of MAR.

• 한국수산과학회지
• /
• 제53권6호
• /
• pp.934-941
• /
• 2020

The spatial and temporal catch variations of Argentine shortfin squid Illex argentinus in the Southwest Atlantic Ocean (SWA) were analyzed using Korean squid-jigging fishery data collected through electronic reporting system (ERS) from 2016 to 2020. The ERS linked with GPS has been implemented for collecting fishing data from all Korean fishing vessels operating in international waters since November 2015. The fishing period of the Korean squid-jigging fishery in the SWA runs from early summer to autumn (December to June) in the Southern Hemisphere. The fishing ground was extended from 42°S to 48°S along the Patagonian continental shelf and slope, and the main fishing ground was formed around the Falkland Islands. The yearly catch per unit effort (CPUE) of I. argentinus fluctuated between 1.69 and 7.53 tons/day. In this study, during the fishing season, a south and westward shift on the fishing ground was observed indicating the feeding migration of the south Patagonian stock. The shift in monthly fishing centroids differed according to fishing season. The gradual southward shifts of fishing centroids were observed in the catch years (2017 and 2018), whereas unapparent shifts in fishing centroids were observed in the low catch years (2016 and 2019).

• 한국정보통신학회논문지
• /
• 제25권8호
• /
• pp.1095-1102
• /
• 2021

성능과 하드웨어 복잡도 사이에 높은 확장성과 유연성을 갖는 확장 가능형 ECC 구조를 제안한다. 구조적 확장성을 위해 유한체 연산을 32 비트 워드 단위로 병렬 처리하는 처리요소의 1차원 배열을 기반으로 모듈러 연산회로를 구현하였으며, 사용되는 처리요소의 개수를 1~8개 범위에서 결정하여 회로를 합성할 수 있도록 설계되었다. 이를 위해 워드 기반 몽고메리 곱셈과 몽고메리 역원 연산의 확장 가능형 알고리듬을 적용하였다. 180-nm CMOS 공정으로 확장 가능형 ECC 프로세서 (sECCP)를 구현한 결과, N_PE=1인 경우에 100 kGE와 8.8 kbit의 RAM으로 구현되었고, N_PE=8인 경우에는 203 kGE와 12.8 kbit의 RAM으로 구현되었다. sECCP가 100 MHz 클록으로 동작하는 경우, N_PE=1인 경우와 N_PE=8인 경우의 P256R 타원곡선 상의 점 스칼라 곱셈을 각각 초당 110회, 610회 연산할 수 있는 것으로 분석되었다.

• 동서간호학연구지
• /
• 제28권1호
• /
• pp.10-20
• /
• 2022

Purpose: We compared the Korean Triage and Acuity Scale (KTAS), Injury Severity Score (ISS), and Revised Trauma Score (RTS) determined the validity of KTAS for classifying trauma patients. Methods: A retrospective chart review of 10,865 trauma patients (aged ≥15 years) who visited a single regional trauma and emergency medical center from January 1, 2016, to December 31, 2020, was conducted. Data were collected from the Korean Trauma Data Bank. Based on KTAS classification, the rates of intensive care unit admission, surgery and intervention, transfusion, emergency room (ER) and hospital mortality, and ER stay time were investigated. Data were analyzed using Chi-square test, Pearson's correlation coefficient, receiver operating characteristic curve, and area under the ROC curve. Results: In the KTAS, severe trauma patients (ISS ≥16) were classified as Level 1 (79.6%), 2 (44.8%), 3 (15.5%), 4 (4.0%) and 5 (7.6%). The following were the predictive powers of KTAS, ISS, and RTS for different parameters: surgery and intervention rate, KTAS (.71), ISS (.70), and RTS (.63); transfusion rate within 4h, KTAS (.82), ISS (.82), and RTS (.74); ER stay time within 90 min, KTAS (.72), ISS (.62), and RTS (.56); and ER mortality, KTAS (.84), ISS (.72), and RTS (.88). These findings were statistically significant (p<.001). The sensitivity and specificity of KTAS for trauma patients were .88 (.87~.90), and .38 (.37~.39), respectively. Conclusion: KTAS is a useful classification system that can predict the clinical outcomes of patients with trauma, and effectively triage acutely ill trauma patients, thus provide appropriate treatment.

• 한국수산과학회지
• /
• 제55권5호
• /
• pp.662-669
• /
• 2022

The purpose of this study is to test the effects of electrolyzed water treatment on dried-laver Pyropia sp. processing facilities to control microbial contamination. Following the progression of the process to the next step, as well as during the lapse between process operating hours, the contamination level of total viable cell counts (TVC) and total coliform (TC) of laver increased. The TVC increased during the aging step, and after the molding-drying steps were completed, it increased by approximately 2.0 log CFU (colony forming unit)/g. Freshwater used for processing in April had a TVC of 4.31 log CFU/mL, which was more polluted than 2.61 log CFU/mL of seawater. Electrolyzed water was used to treat the sponge used in the laver-molding process, which resulted in a 2 log CFU/mL decrease.The TVC of dried-laver decreased by 1 to 2 log CFU/g when electrolyzed water was applied to the process. In conclusion, application of electrolyzed water in dried-laver processing was shown to be effective in reducing the microbiological contamination of the final product.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• 제24권3호
• /
• pp.265-272
• /
• 2021

Purpose: Hypertrophic pyloric stenosis (HPS) is the most common cause of gastric obstruction in newborns. Extra-mucosal pyloromyotomy can be performed through a small laparotomy or laparoscopy. The aim of this study was to compare the two surgical techniques. We also analyzed the incidence of HPS in infants in the last 10 years in relation to the demographic trend of our province. Methods: We analyzed all the cases of HPS treated at our Unit between January 2010 and December 2019. The data were obtained from operating systems. Data about the demographic trends, in particular, the number of births and the population residing in the province of Verona from 2010 to 2019, were also retrieved. Results: During the study period, 60 patients were treated for HPS and met the inclusion criteria. Of these, 56 males and 4 females with an average age of 38±14 days at surgery were included. No differences were found in terms of the duration of surgery, post-operative complications, duration of hospitalization, and weight at the time of surgery. The only statistically significant data was the chlorine level in cases with and without post-operative vomiting (97±3.5 vs. 102±3.3 mmol/L, p<0.05). There was a lower incidence of HPS from 2014 to 2019; however, there was no significant evidence regarding the correlation between this and the reduced birth rate recorded in the province of Verona during the same period. Conclusion: Although laparoscopic pyloromyotomy is a highly complex procedure, it is a feasible alternative to the classic open technique.

• 대한토목학회논문집
• /
• 제42권6호
• /
• pp.837-842
• /
• 2022

2013년에 개발된 지능형 철도선형계획 프로그램(ei-Rail)은 주로 해외의 신규 철도건설사업 사전 기획 분석 및 설계 결과 검증 등에 활용되어왔다. 그러나 한국 철도산업의 해외 진출 대상국인 개발도상국에서는 대규모 비용이 소요되는 신규 철도건설사업 보다는 기존 철도의 선형개량을 통한 증속, 또는 단선철도의 복선화 등의 사업이 보다 필요하고 실행가능성이 높은 것으로 판단되며, 이런 유형의 사업수요가 지속적으로 발생하고 있다. 이에 본 연구에서는 기존의 신규 철도건설 사업 분석기능 중심의 ei-Rail 프로그램에 철도복선화 사업 분석기능을 추가하고자, 철도 복선화사업 모듈을 개발하였다. 기존에 운행 중인 철도 선형자료를 기반으로 복선화 사업의 종류와 규모를 반영하고 대상 지역별 공종 단가를 적용하여 공사비를 산출하고 설계도면 제작을 자동화할 수 있도록 하였다. 그리고 해외의 사례 적용을 통하여 ei-Rail의 복선화 사업 분석기능을 검증하였다. 향후 해외를 대상으로 하는 철도 복선화 사업의 기획 및 분석결과 검증을 보다 효율적으로 수행할 수 있을 것으로 기대한다.