• Wind and Structures
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• v.37 no.4
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• pp.315-329
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• 2023

We investigated the wind characteristics in the near-surface layer during the landfall of Typhoon Mujigae (2015) based on observations from wind towers in the coastal areas of Guandong province. Typhoon Mujigae made landfall in this region from 01:00 UTC to 10:00 UTC on October 4, 2015. In the region influenced by the eyewall of the tropical cyclone, the horizontal wind speed was characterized by a double peak, the wind direction changed by >180°, the vertical wind speed increased by three to four times, and the angle of attack increased significantly to a maximum of 7°, exceeding the recommended values in current design criteria. The vertical wind profile may not conform to a power law distribution in the near-surface layer in the region impacted by the eyewall and spiral rainband. The gust factors were relatively dispersed when the horizontal wind speed was small and tended to a smaller value and became more stable with an increase in the horizontal wind speed. The variation in the gust factors was the combined result of the height, wind direction, and circulation systems of the tropical cyclone. The turbulence intensity and the downwind turbulence energy spectrum both increased notably in the eyewall and spiral rainband and no longer satisfied the assumption of isotropy in the inertial subrange and the -5/3 law. This result was more significant in the eyewall area than in the spiral rainband. These results provide a reference for forecasting tropical cyclones, wind-resistant design, and hazard prevention in coastal areas of China to reduce the damage caused by high winds induced by tropical cyclones.

• Analytical Science and Technology
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• v.37 no.2
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• pp.98-113
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• 2024

The current investigation entails the characterization of five degradation products (DPs) formed under different stress conditions of loteprednol using liquid chromatography-tandem mass spectrometry (LC-MS/MS). In addition, this study developed a stable high-performance liquid chromatography (HPLC) method for evaluating loteprednol along with impurities. The method conditions were meticulously fine-tuned which involved the exploration of the appropriate solvent, pH, flow of the mobile phase, columns, and wavelength. The method conditions were carefully chosen to successfully resolve the impurities of loteprednol and were employed in subsequent validation procedures. The stability profile of loteprednol was exposed to stress degradation experiments conducted under five conditions, and DPs were structurally characterized by employing LC-MS/MS. The chromatographic resolution of loteprednol and its impurities along with DPs was effectively achieved using a Phenomenex Luna 250 mm C18 column using 0.1 % phosphoric acid, methanol, and acetonitrile in 45:25:30 (v/v) pumped isocratically at 0.8 mL/min with 243 nm wavelength. The method produces an accurate fit calibration curve in 50-300 ㎍/mL for loteprednol and LOQ (0.05 ㎍/mL) - 0.30 ㎍/mL for its impurities with acceptable precision, accuracy, and recovery. The stress-induced degradation study revealed the degradation of loteprednol under basic, acidic, and photolytic conditions, resulting in the formation of seven distinct DPs. The efficacy of this method was validated through LC-MS/MS, which allowed for the verification of the chemical structures of the newly generated DPs of loteprednol. This method was appropriate for assessing the impurities of loteprednol and can also be appropriate for structural and quantitative assessment of its degradation products.

• Korean Journal of Radiology
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• v.25 no.3
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• pp.301-313
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• 2024

Objective: The current body of evidence lacks clarity regarding the comparative efficacy and safety of radiofrequency ablation (RFA) and microwave ablation (MWA) as minimally invasive treatments for benign thyroid nodules. The primary objective of this study is to clarify these concerns. Materials and Methods: A comprehensive search was conducted using the Cochrane Library, Scopus, Europe PMC, and Medline databases until October 10th, 2023, using a combination of relevant keywords. This study incorporated literature that compared RFA and MWA for benign thyroid nodules. The primary outcome was the volume reduction ratio (VRR) from baseline to follow-up. Secondary outcomes were symptom score, cosmetic score, ablation time, major complications rate, hemorrhage, hoarseness, skin burn, cough, and sympathetic nerve injury. We used Risk of Bias in Non-randomized Studies - of Interventions (ROBINS-I) tool to assess the risk of bias in the included studies. We employed random effects models to analyze the standardized mean difference (SMD) and odds ratio for the presentation of outcomes. Results: Nine studies with 2707 nodules were included. The results of our meta-analysis indicated similar efficacy between RFA and MWA in terms of VRR during the 1 (SMD 0.06; 95% confidence interval [CI]: -0.13 to 0.26; P = 0.52) and 3 (SMD 0.11; 95% CI: -0.03 to 0.25; P = 0.12) months of follow-up. VRR was significantly higher in RFA than in MWA at the 6 (SMD 0.25; 95% CI: 0.06-0.43; P = 0.008) and 12 month of follow-up (SMD 0.38; 95% CI: 0.17 to 0.59; P < 0.001). There were no significant differences between RFA and MWA in symptom scores, cosmetic scores, or the incidence of complications, including hemorrhage, hoarseness, skin burn, cough, and sympathetic nerve injury. Conclusion: RFA showed a higher VRR than MWA at 6 and 12-month follow-ups, with a comparable safety profile.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.4
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• pp.360-369
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• 1987

The relationship between the catches of tuna and hydrographic conditions in South-East Pacific region (latitude $5^{\circ}N-12^{\circ}S$, longitude $135^{\circ}W-115^{\circ}W$) was investigated by using the catch data of tuna and Digital Bathythermograph (DBT) data from December 9, 1980 to April 2, 1981. The results are as follows : The study area were located in South Eguatorial Current regions including equatorial upwelling regions in $5^{\circ}N\;to\;12^{\circ}S$. The horizontal mean temperature at the depth of 10m on the first quarter months in the study area was about $25^{\circ}C$C and the salinity of those fishing areas ranged from 34.8 to $35.0\%_{\circ}$. Yellowfin tuna and bigeye tuna were mainly caught in SW vertical temperature profile type, which the depth of thermocline ranged from loom to 300m, and temperature difference of thermocline was about $12^{\circ}C$. The deeper the depth of thermocline, the more the catches of tuna. While albacore tuna was caught well in SS vertical temperature profile type which the temperature of thermocline ranged from $9^{\circ}\;to\;26^{\circ}C$ and its gradient was very smooth. The depth of 1 ml/l surface of dissoved oxygen content ranged from loom to 200m in the South-East Pacific between longitude $140^{\circ}W-100^{\circ}W$, but it was shallower than 100 m near the North-South American continent. The catches of bigeye tuna were larger than those of yellowfin tuna in South Equatorial Current region. As approaching to the South and North American continent, the catches of yellowfin tuna and bigeye tuna decreased because the thermocline becomes shallower and steeper and the depth of the 1 m1/1 surface of dissolved oxygen content became shallower.

• The Journal of Korean Academy of Sensory Integration
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• v.21 no.1
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• pp.47-58
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• 2023

Objective : This study aimed to investigate the current status and actual use of assessment tools by institutions in the field of occupational therapy with children in Korea. Methods : The study was conducted with 67 occupational therapists working with children in Korea. To investigate the use of evaluation tools by area, knowledge of the evaluation tools, and desire to participate in further education, the questionnaires used in studies by Lee, Hong, and Park (2018) and Kim (2015) were modified and supplemented according to the child evaluation tools currently in usein institutions in Korea. For data collection, we distributed Google questionnaires to child occupational therapists for 3 weeks using convenience sampling. Excel was used to analyze the use of the evaluation tools according to institution. Technical statistics and frequency analyses were used to verify the general characteristics, evaluation-related information, status of evaluation tool use, knowledge levels relating to evaluation tools, and desire to participate in education. A t-test was used for the evaluation tool status. Results : Welfare centers used the most evaluation tools, with an average of 11.1, followed by university hospitals, rehabilitation hospitals, clinics, and daycare centers. There were differences in the choice of tools used, hospital with the Jebsen-Taylor hand function test and the Wee-FIM (Functional Independence Measure) being the most frequently applied. Centers, daycare centers, and welfare center the Sensory Profile test and clinical observation were also used often. Regarding the level of knowledge of evaluation tools and the desire to participate further in education, 30 (44.8%) of the respondents had not completed their education, and 42 (62.7%) rated their knowledge level as generally low. When asked about the importance of using a manual to guide them in their use of evaluation tools, 66 (98.6%) answered positively, and 66 (98.6%) answered that they needed specialized training in the use of evaluation tools. Conclusion : This study makes it possible to understand the use and status of evaluation tools as used by different institutions in Korea in the field of child occupational therapy It is anticipated that it will provide the basis for introducing existing evaluation tools and preparing new evaluation tools to be used in this field in Korea.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.144-150
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• 2019

In this study, resistance spot welding was performed using a high tensile steel plate SGAFC 780. The shear tensile strength, fracture profile, nugget diameter, and simulation were compared according to the conditions. After the nugget diameter calibration, the minimum diameter of welding was more than 4.3mm when the welding current was 8kVA or more. At 9kVA and above 10kVA, the minimum nugget diameter of 4.3mm was satisfied. On the other hand, due to the high current and time, the fly phenomenon occurred and the deep indentation remained. An evaluation of the weldability confirmed that there was an interval that was evaluated as weld failure due to the creep phenomenon, which satisfied the tensile shear strength and minimum nugget diameter. On the other hand, areas that have sufficient load bearing capacity even when drift has occurred were also identified. The simulation results show that the error rate was less than 4.2% when comparing the nugget diameter in the simulation and the experimental results in the appropriate weld zone, and confirmed the reliability of the simulation.

• Journal of Korean Society for Atmospheric Environment
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• v.33 no.3
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• pp.205-216
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• 2017

Carbonaceous aerosols such as the equivalent black carbon (eBC), the elemental carbon (EC) and the organic carbon (OC) were monitored at the Seoul Olympic Park site ($37.521^{\circ}N$, $127.124^{\circ}E$) during the KORUS-AQ 2016 campaign using a Multi Angle Absorption Photometer (MAAP) and an OCEC Analyzer. Averaged mass concentrations of eBC, EC and OC were presented as $2.46{\pm}1.52{\mu}g/m^3$, $1.01{\pm}0.60{\mu}g/m^3$ and $4.85{\pm}2.60{\mu}g/m^3$, respectively. OC/EC ratio and mass absorption cross-section (MAC) of light absorbing aerosols were calculated as 2.32 and $14.8m^2/g$, respectively. Diesel OC concentrations were estimated from a source profile of diesel vehicles as well. eBC mass concentrations measured from May $26^{th}$ to May $27^{th}$, 2016 showed 40% higher than averaged eBC mass concentrations during campaign period. $PM_{2.5}$ concentrations measured in this period were also higher than average $PM_{2.5}$ concentrations. High eBC concentrations were observed from May $29^{th}$ to May $31^{st}$, 2016 and from June $9^{th}$ to June $11^{th}$, 2016, possibly due to morning rush hour and the effect of temperature inversion at night. Diurnal variations of eBC, EC and Diesel OC showed a typical pattern of metropolitan area. In the weekend, however, diurnal variations of eBC, EC and Diesel OC mass concentrations were different from those measured in the weekday. It is expected that this study can help to understand the relationship between carbonaceous aerosols in a metropolitan area.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7897-7907
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• 2014

Background: There is paucity of studies defining the prevalence of non-communicable disease (NCD) risk factors in Saudi Arabia despite the surging epidemic of obesity, change in dietary habits and sedentary lifestyle. Objectives: This cross-sectional study aimed to assess the prevalence of NCDs risk factors among employees at King Faisal University in Al Hassa, Saudi Arabia and to determine the possible correlates for clustering of NCDs risk factors among them. Materials and Methods: All employees were invited to participate; the World Health Organization STEPwise approach was used for data collection which consisted of a personal interview to collect socio-demographic characteristics, NCD history, tobacco use, vegetables and fruit consumption, and physical activity (PA), followed by anthropometric measurements namely weight, height and waist circumference and blood pressure measurements, subjects were finally subjected to biochemical tests with determination of fasting plasma glucose, serum triglycerides, cholesterol and high density lipoproteins. Results: Of the surveyed employees (n=691), daily current smokers accounted for 22.7%. 94.9%, 95.1% and 86% consumed < 5 servings per day of vegetables, fruits and both fruits and vegetables respectively, 73% were physically inactive, 64% were overweight or obese, 22.1% had hypertension, and 21.5% were diabetics. Elevated cholesterol levels were found in 36.6%, low high density lipoproteins in 36.8%, and elevated triglycerides in 36.1%. Only 3% had no NCD risk factors, and 57.6% had ${\geq}3$ factors. Multivariate logistic regression showed that gender (being male, adjusted odds ratio 'aOR'=1.51), aged ${\geq}50$ years (aOR=3.06), < college education (aOR=1.75), current smokers (aOR=2.37), being obese (aOR=6.96) and having a low PA level (aOR=4.59) were the significant positive predictors for clustering of NCD risk factors. Conclusions: Over fifty percent of the studied university's employees had multiple (${\geq}3$) NCD risk factors. Screening and health promotion initiatives should be launched at least targeting the modifiable factors to avert the excessive risk for cardiovascular disease, diabetes mellitus and several types of cancers.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.2
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• pp.130-137
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• 2012

The underwater glider using conception of Lagrangian method, is a new observation platform to understand the properties of the ocean vertically. In 2011 March, KORDI made a first successful autonomous trip from Hupo to west coast of Uleungdo piloting Littoral Glider of Alaska Native Technology LLC. The journey considered many environmental variables and route vigilantly selected, the glider covered 177 km horizontally and took approximately 6 days (153 hours). Despite the existence of 1 kt eddy current, Sound velocity sampling was conducted from 5 meters and reaching maximum of 200 meters depth at each dive. It successfully collected sound velocity and temperature profile at every 5 seconds totaling up to 1408 profiles using SVT&P sensor. During the flight it was also a mission to check the diverse modes of the glider i.e. spiral, waypoints, heading, drift and hover could function without a defect in a given situation. These modes were thoroughly monitored and it could be considered that the glider handled it well during the flight. As a result of this test flight, it was evident that the given underwater glider could operate under 2kt current environment with users defined heading and depth, also with the payload up to 5 kg without changing internal buoyancy.

• Asia pacific journal of information systems
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• v.22 no.4
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• pp.125-149
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• 2012

As the smart phone is propagating rapidly, the importance of mobile advertisement has also grown. One of the main characteristics of the Internet and smart phone advertising is that they can deliver personalized advertisements to each customer. The smart phone enables the identification of additional personalized information such as the customer's location and the accessibility to the site at any place any time. As the Internet platform becomes richer, firms that offer the ad services via the wired PC Internet and wireless smart phone are seeking various types of personalized ads. However, their service platform and Information and Communication Technology (ICT) platform should be suitable to the characteristics of personalized ads. This research explores various types of personalized ad methods and evaluates their adequacy encompassing four types of ad service platforms (such as search portal, news portal, e-mall servers, and SNS) and two types of ICT platforms (PC Internet and smart phone). To this end, we classified the personalized ads into seven types: three basic types and four composite types. The basic types of ad methods are identified by considering the current activity that the customer is engaged, the individual profile and log history, and the customer's current location or planning location. Four composite types of ad methods are constructed as the combination of these basic types. For those types of ad methods, we evaluate whether each ad method adequately maps with four types of ad service platforms and two types of ICT platforms. We proposed a metric of evaluation and demonstrated the concept with illustrative numbers. Specifically, we analyze and compare personalized ad methods in three ways. Firstly, the possibility of implementing a personalized ad method on the platform is analyzed to confirm the degree of suitability. Secondly, the value of personalized ad method is analyzed based on the customer accessibility. Lastly, expected effectiveness for each personalized ad method is computed by multiplying the possibility and the value. Through this kind of analysis, the ad service providers as well as advertising companies can evaluate what kinds of personalized ad methods and platforms are possible and suitable to maximize their ad effectiveness on the Internet and smart phone platforms.