• Journal of Internet of Things and Convergence
• /
• v.10 no.2
• /
• pp.85-91
• /
• 2024

In this paper, we studied projection mapping, which is being utilized as a digital canvas beyond space and time for theme parks, mega events, and exhibition performances. Since the existing projection technology used for fixed objects has the limitation that it is difficult to map moving objects in terms of utilization, it is urgent to develop a technology that can track and map moving objects and a real-time dynamic projection mapping system based on dynamically moving objects so that it can respond to various markets such as performances, exhibitions, and theme parks. In this paper, we propose a system that can track real-time objects in real time and eliminate the delay phenomenon by developing hardware and performing high-speed image processing. Specifically, we develop a real-time object image analysis and projection focusing control unit, an integrated operating system for a real-time object tracking system, and an image processing library for projection mapping. This research is expected to have a wide range of applications in the technology-intensive industry that utilizes real-time vision machine-based detection technology, as well as in the industry where cutting-edge science and technology are converged and produced.

• Journal of the Korean Society for Library and Information Science
• /
• v.58 no.1
• /
• pp.99-122
• /
• 2024

This study investigated librarians' awareness of and demand for the librarian learning community in order to successfully introduce and operate the librarian learning community. For this purpose, an online survey was conducted targeting current librarians and a total of 474 responses were collected. The main analysis results are as follows. Firstly, librarians showed a very low awareness of the librarian learning community, while they highly evaluated the purpose and significance of such a community. Secondly, the motivations for librarians to participate in the librarian learning community were primarily focused on professional growth, solidarity with colleagues, and satisfaction of intellectual curiosity, in that order. Thirdly, the ultimate values of the librarian learning community were identified as improving library services, enhancing professionalism, fostering collaborative group exploration, sharing values and visions. Fourthly, the success factors of the librarian-learning community were ranked as follows: member voluntarism, a culture of collaboration among members, dedicated time (once a week), and a supportive environment (budget, space, etc.). On the other hand, the failure factors were identified as a lack of time due to heavy workloads, lack of member voluntarism, indifference from superiors, and insufficient support environment (budget, space, etc.). Finally, the willingness to participate is also very high. Furthermore, it was observed that there is a wide range of interests in various topics among librarians. The results of this study are expected to be useful as basic data for determining practical operation methods or selecting topics when operating a librarian learning community in the future.

• Journal of Trauma and Injury
• /
• v.37 no.1
• /
• pp.20-27
• /
• 2024

Purpose: Severe abdominal injuries often require immediate clinical assessment and surgical intervention to prevent life-threatening complications. In Jeju Regional Trauma Center, we have instituted a protocol for emergency department (ED) laparotomy at the trauma bay. We investigated the mortality and time taken from admission to ED laparotomy. Methods: We reviewed the data recorded in our center's trauma database between January 2020 and December 2022 and identified patients who underwent laparotomy because of abdominal trauma. Laparotomies that were performed at the trauma bay or the ED were classified as ED laparotomy, whereas those performed in the operating room (OR) were referred to as OR laparotomy. In cases that required expeditious hemostasis, ED laparotomy was performed appropriately. Results: From January 2020 to December 2022, 105 trauma patients admitted to our hospital underwent emergency laparotomy. Of these patients, six (5.7%) underwent ED laparotomy. ED laparotomy was associated with a mortality rate of 66.7% (four of six patients), which was significantly higher than that of OR laparotomy (17.1%, 18 of 99 patients, P=0.006). All the patients who received ED laparotomy also underwent damage control laparotomy. The time between admission to the first laparotomy was significantly shorter in the ED laparotomy group (28.5 minutes; interquartile range [IQR], 14-59 minutes) when compared with the OR laparotomy group (104 minutes; IQR, 88-151 minutes; P<0.001). The two patients who survived after ED laparotomy had massive mesenteric bleeding, which was successfully ligated. The other four patients, who had liver laceration, kidney rupture, spleen injury, and pancreas avulsion, succumbed to the injuries. Conclusions: Although ED laparotomy was associated with a higher mortality rate, the time between admission and ED laparotomy was markedly shorter than for OR laparotomy. Notably, major mesenteric hemorrhages were effectively controlled through ED laparotomy.

• Journal of Aerospace System Engineering
• /
• v.18 no.1
• /
• pp.37-45
• /
• 2024

This paper presents a design approach for passive vibration control to reduce vertical vibrations transmitted to the control unit during hovering flight of a quadrotor drone. Ground vibration test simulation based on finite element model was performed for forced vibration analysis of the quadrotor drone. First, modal analysis was performed to evaluate dynamic characteristics. Forced vibration response analysis was then performed to obtain the steady-state response within the operating frequency range under the hovering flight condition. Furthermore, to obtain the vibration reduction effect, a viscous damping tape was applied at positions that could induce vibrations transmitted to the control unit under the same conditions. Such a passive vibration control approach was investigated. Relevant vibration reduction effect was assessed with respect to the application of damping materials and the attachment position.

• Korean Journal of Radiology
• /
• v.22 no.12
• /
• pp.1964-1973
• /
• 2021

Objective: To investigate the diagnostic performance of CT fractional flow reserve (CT-FFR) for myocardial bridging-related ischemia using dynamic CT myocardial perfusion imaging (CT-MPI) as a reference standard. Materials and Methods: Dynamic CT-MPI and coronary CT angiography (CCTA) data obtained from 498 symptomatic patients were retrospectively reviewed. Seventy-five patients (mean age ± standard deviation, 62.7 ± 13.2 years; 48 males) who showed myocardial bridging in the left anterior descending artery without concomitant obstructive stenosis on the imaging were included. The change in CT-FFR across myocardial bridging (ΔCT-FFR, defined as the difference in CT-FFR values between the proximal and distal ends of the myocardial bridging) in different cardiac phases, as well as other anatomical parameters, were measured to evaluate their performance for diagnosing myocardial bridging-related myocardial ischemia using dynamic CT-MPI as the reference standard (myocardial blood flow < 100 mL/100 mL/min or myocardial blood flow ratio ≤ 0.8). Results: ΔCT-FFR_systolic (ΔCT-FFR calculated in the best systolic phase) was higher in patients with vs. without myocardial bridging-related myocardial ischemia (median [interquartile range], 0.12 [0.08-0.17] vs. 0.04 [0.01-0.07], p < 0.001), while CT-FFR_systolic (CT-FFR distal to the myocardial bridging calculated in the best systolic phase) was lower (0.85 [0.81-0.89] vs. 0.91 [0.88-0.96], p = 0.043). In contrast, ΔCT-FFR_diastolic (ΔCT-FFR calculated in the best diastolic phase) and CT-FFR_diastolic (CT-FFR distal to the myocardial bridging calculated in the best diastolic phase) did not differ significantly. Receiver operating characteristic curve analysis showed that ΔCT-FFR_systolic had largest area under the curve (0.822; 95% confidence interval, 0.717-0.901) for identifying myocardial bridging-related ischemia. ΔCT-FFR_systolic had the highest sensitivity (91.7%) and negative predictive value (NPV) (97.8%). ΔCT-FFR_diastolic had the highest specificity (85.7%) for diagnosing myocardial bridging-related ischemia. The positive predictive values of all CT-related parameters were low. Conclusion: ΔCT-FFR_systolic reliably excluded myocardial bridging-related ischemia with high sensitivity and NPV. Myocardial bridging showing positive CT-FFR results requires further evaluation.

• Korean Journal of Radiology
• /
• v.20 no.5
• /
• pp.791-800
• /
• 2019

Objective: To compare various models of diffusion-weighted imaging including monoexponential apparent diffusion coefficient (ADC), biexponential (fast diffusion coefficient [D_f], slow diffusion coefficient [D_s], and fraction of fast diffusion), stretched-exponential (distributed diffusion coefficient and anomalous exponent term [α]), and kurtosis (mean diffusivity and mean kurtosis [MK]) models in the differentiation of renal solid masses. Materials and Methods: A total of 81 patients (56 men and 25 women; mean age, 57 years; age range, 30-69 years) with 18 benign and 63 malignant lesions were imaged using 3T diffusion-weighted MRI. Diffusion model selection was investigated in each lesion using the Akaike information criteria. Mann-Whitney U test and receiver operating characteristic (ROC) analysis were used for statistical evaluations. Results: Goodness-of-fit analysis showed that the stretched-exponential model had the highest voxel percentages in benign and malignant lesions (90.7% and 51.4%, respectively). ADC, D_s, and MK showed significant differences between benign and malignant lesions (p < 0.05) and between low- and high-grade clear cell renal cell carcinoma (ccRCC) (p < 0.05). α was significantly lower in the benign group than in the malignant group (p < 0.05). All diffusion measures showed significant differences between ccRCC and non-ccRCC (p < 0.05) except D_f and α (p = 0.143 and 0.112, respectively). α showed the highest diagnostic accuracy in differentiating benign and malignant lesions with an area under the ROC curve of 0.923, but none of the parameters from these advanced models revealed significantly better performance over ADC in discriminating subtypes or grades of renal cell carcinoma (RCC) (p > 0.05). Conclusion: Compared with conventional diffusion parameters, α may provide additional information for differentiating benign and malignant renal masses, while ADC remains the most valuable parameter for differentiation of RCC subtypes and for ccRCC grading.

• Journal of Radiation Protection and Research
• /
• v.41 no.1
• /
• pp.31-39
• /
• 2016

Background: It is necessary to consider the overall countermeasure for analysis of nuclear activities according to the increase of the nuclear facilities like nuclear power and reprocessing plants in the neighboring countries including China, Taiwan, North Korea, Japan and South Korea. South Korea and comprehensive nuclear-test-ban treaty organization (CTBTO) are now operating the monitoring instruments to detect radionuclides released into the air. It is important to estimate the origin of radionuclides measured using the detection technology as well as the monitoring analysis in aspects of investigation and security of the nuclear activities in neighboring countries. Materials and methods: A three-dimensional forward/backward trajectory model has been developed to estimate the origin of radionuclides for a covert nuclear activity. The developed trajectory model was composed of forward and backward modules to track the particle positions using finite difference method. Results and discussion: A three-dimensional trajectory model was validated using the measured data at Chernobyl accident. The calculated results showed a good agreement by using the high concentration measurements and the locations where was near a release point. The three-dimensional trajectory model had some uncertainty according to the release time, release height and time interval of the trajectory at each release points. An atmospheric dispersion model called long-range accident dose assessment system (LADAS), based on the fields of regards (FOR) technique, was applied to reduce the uncertainties of the trajectory model and to improve the detective technology for estimating the radioisotopes emission area. Conclusion: The detective technology developed in this study can evaluate in release area and origin for covert nuclear activities based on measured radioisotopes at monitoring stations, and it might play critical tool to improve the ability of the nuclear safety field.

• Journal of Food Hygiene and Safety
• /
• v.31 no.5
• /
• pp.327-334
• /
• 2016

This study was conducted to establish the standard method for the contents of biotin in milk formulas. To optimize the method, we compared several conditions for liquid extraction, purification and instrumental measurement using spiked samples and certified reference material (NIST SRM 1849a) as test materials. LC-MS/MS method for biotin was established using $C_{18}$ column and binary gradient 0.1% formic acid/acetonitrile, 0.1% formic acid/water mobile phase is applied for biotin. Product-ion traces at m/z 245.1 ${\rightarrow}$ 227.1, 166.1 are used for quantitative analysis of biotin. The linearity was over $R^2=0.999$ in range of $5{\sim}60{\mu}g/L$. For purification, chloroform was used as a solvent for eliminating lipids in milk formula. The linearity was over 0.999 in range of 5~60 ng/mL. The detection limit and quantification limit were 0.10, 0.31 ng/mL. The accuracy and precision of LC-MS/MS method using CRM were 103%, 2.5% respectively. Optimized methods were applied in sample analysis to verify the reliability. All the tested milk formulas were acceptable contents of biotin compared with component specification and standards for nutrition labeling. The standard operating procedures were prepared for biotin to provide experimental information and to strengthen the management of nutrient in milk formula.

• Journal of Animal Environmental Science
• /
• v.14 no.2
• /
• pp.129-138
• /
• 2008

This study was carried out to investigate the operating characteristics, water balance and chemical properties of compost during the composting with pig slurry on-farm trial. The composting plant with sawdust pile filteration was done in a forced aeration inside a house and equipped with a turning machine moving on a rails. The composting pit was 4.6m wide, 53m long and the maximum height was 2m. A field scale aerobic composting facility was tested the composting efficiency of high moisture pig slurry. The sawdust materials remained 6 months. Pig slurry was added to compost pile every other day during 6 months run. The temperature in compost pile and compost house, and input and output of moisture were measured during composting process. The result are summarized as follows; 1. The temperature of compost was varied in range of at $22.4^{\circ}C{\sim}71.1^{\circ}C$. After turning, the composting temperature decreased to $50^{\circ}C{\sim}36^{\circ}C$ during $3{\sim}5$ hours, and then raised to $64.5^{\circ}C$ 2. The temperature of compost house was maintained $20^{\circ}C{\sim}30^{\circ}C$, and relative humidity was varied in range of $50{\sim}99%$. 3. BOD, CODcr and SS of leachate water was reduced 89.5%, 81.2%, 97.5%, respectively. 4. The content of heavy metal in the final compost was lower those of Korea standards. 5. The amount of effluent was 10.2%. Total evaporation during composting Period were 74.8%. The amount of slurry per $1m^3$ sawdust was $3.16m^3$ without treatment of effluent output.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.14 no.2
• /
• pp.128-132
• /
• 2010

Purpose: Nuclear medicine general operation room is radioactive control room which is used for the handling of radioisotope(R.I). Radioactive contamination materials must be under control and separated from general trash. With this experiments, we want to actively suggest the guideline of controling and operating radioactive contamination materials by measuring contamination degree and analyzing the causes which is not realized so far. Materials and Methods: Materials are selected from Oct. 2009 to March. 2010. salines which are used for labelling radiophamaceuticals and generator cap, saline needle cap, $^{99m}Tc$-needle cap saline vial which is generated from $^{99}Mo$/$^{99m}Tc$ generator. After measuring each surface contamination degree by survey meter, mean value and standard deviation one were solved out. Results: In result, After measuring surface contamination degree, radioactivity of saline for labelling radiophamaceuticals showed $14429{\pm}26378$ cpm (p<0.05) and in measured generators, foreign imported things showed that generator cap : $9{\pm}21$ cpm, saline vial : $17{\pm}28$ cpm. saline needle cap : $35{\pm}66$ cpm, $^{99m}Tc$-needle cap : $9{\pm}21$ cpm, saline vial $13{\pm}28$ cpm. domestic things showed that generator cap : $22852{\pm}52545$ cpm, saline needle cap : $87367{\pm}109711$ cpm, $^{99m}Tc$-needle cap : $9008{\pm}10459$ cpm, saline vial : $186416{\pm}158196$ cpm (p<0.05). Conclusion: The saline which is used for labelling, exceeded 1/10 of maximum permissible range. this is generated from radiophamaceuticals dilution procedure. and In generators, radioactive value of foreign import things showed closely background value. but which of domestic thing showed that exceeded more than 1000 values 1/10 of maximum permissible range. the causes of that is domestic generator is contaminated in manufacturing procedure. So, to dispose radioactive contamination materials which is could betaken out of, the control and operation must be radical under controlled by radioactive measuring, recording and equipping of its own. if this is kept well, we can prevent surely that radioactive waste could be disposed like as general trash.