• The Korea Journal of Herbology
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• v.39 no.3
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• pp.107-114
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• 2024

Objective : Cicadae Periostracum (CP), which is the discarded shell of the Cryptotympana atrata (Fabricius, 1775), is a recognized component of oriental medicine for treatment sore throat, itching, shock, sedation, edema. However, the safety and toxicity of CP have not yet been established. It has been reported that symptoms of addiction or side effects may occur in patients who take high doses of CP or who are hypersensitive to it. Therefore, we investigated the acute toxicity of an CP extracts in Sprague-Dawley (SD) rats. Methods : To study acute toxicity, five SD rats of each sex per group were treated with CP extracts at single doses of 0, 500, 1000, or 2000 mg/kg administrated by oral gavage, and body weight, clinical signs, and mortality were observed after dosing. At the end of 14-day observation period, all animals were sacrificed and complete hematological and macroscopic examinations were performed. Results : There were no dead animal and test article-related effects on body weight change or the gross finding. No toxicologically significant results were observed between control and treated groups in hematology. Although salivation related to stress at the highest dose was observed in clinical signs immediately after administration, it is considered to have no toxicological significance. Conclusion : As the results, we did not find any adverse effect at the dose levels of 500, 1000, or 2000 mg/kg in rats. The minimal lethal dose was considered to be over 2000 mg/kg body weight in rats.

• Journal of Navigation and Port Research
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• v.48 no.3
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• pp.214-220
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• 2024

Remote control is used for operating maritime autonomous surface ships. The operator controls the ship using control data generated by the remote control system. To ensure successful remote control, three principles must be followed: safety, reliability, and availability. To achieve this, the suitability of both the control data and operators for remote control must be established. Currently, there are no international regulations in place for evaluating remote control suitability through experiments on actual ships. Conducting such experiments is dangerous, costly, and time-consuming. The goal of this study is to develop a suitability evaluation method using the output values of control devices used in actual ship operation. The proposed method involves evaluating the suitability of data by analyzing the output values and evaluating the suitability of operators by examining their tracking of these output values. The experiment was conducted using a shore-based remote control system to operate the training ship 'Hannara' of Korea National Maritime and Ocean University. The experiment involved an iterative process of obtaining the operator's tracking value for the output value of the ship's control devices and transmitting and receiving tracking data between the ship and the shore. The evaluation results showed that the transmission and reception performance of control data was suitable for remote operation. However, the operator's tracking performance revealed a need for further education and training. Therefore, the proposed evaluation method can be applied to assess the suitability and analyze both the control data and the operator's compliance with the three principles of remote control.

• Steel and Composite Structures
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• v.50 no.3
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• pp.281-298
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• 2024

Stainless steel bolts (SSB) are increasingly utilized in bolted steel connections due to their good mechanical performance and excellent corrosion resistance. Fire accidents, which commonly occur in engineering scenarios, pose a significant threat to the safety of steel frames. The post-fire behavior of SSB has a significant influence on the structural integrity of steel frames, and neglecting the effect of temperature can lead to serious accidents in engineering. Therefore, it is important to evaluate the performance of SSB at elevated temperatures and their residual strength after a fire incident. To investigate the mechanical behavior of SSB after fire, 114 bolts with grades A4-70 and A4-80, manufactured from 316L austenitic stainless steel, were subjected to elevated temperatures ranging from 20℃ to 1200℃. Two different cooling methods commonly employed in engineering, namely cooling at ambient temperatures (air cooling) and cooling in water (water cooling), were used to cool the bolts. Tensile tests were performed to examine the influence of elevated temperatures and cooling methods on the mechanical behavior of SSB. The results indicate that the temperature does not significantly affect the Young's modulus and the ultimate strength of SSB. Up to 500℃, the yield strength increases with temperature, but this trend reverses when the temperature exceeds 500℃. In contrast, the ultimate strain shows the opposite trend. The strain hardening exponent is not significantly influenced by the temperature until it reaches 500℃. The cooling methods employed have an insignificant impact on the performance of SSB. When compared to high-strength bolts, 316L austenitic SSB demonstrate superior fire resistance. Design models for the post-fire mechanical behavior of 316L austenitic SSB, encompassing parameters such as the elasticity modulus, yield strength, ultimate strength, ultimate strain, and strain hardening exponent, are proposed, and a more precise stress-strain model is recommended to predict the mechanical behavior of 316L austenitic SSB after a fire incident.

• The Korean Society of Law and Medicine
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• v.24 no.3
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• pp.105-124
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• 2023

Modern society is facing an unstable environment due to unexpected accidents and hazardous situations. For example, incidents such as the collapse of the Bundang Bridge and the crushing accident in Itaewon could serve as examples. In addition to these, critical emergencies like sudden cardiac arrests and strokes frequently occur, requiring swift actions and smooth transfers to specialized medical institutions for effective responses. In response to these risks, the country has been establishing various systems to protect the lives and safety of its citizens. Among these, the 119 First Aid Activities plays a crucial role within the emergency medical system. Its goal is to promptly respond to critical emergency situations involving severe trauma patients or patients with serious illnesses, minimizing damage and safeguarding lives by swiftly transferring them to emergency medical institutions for specialized treatment. The core activity related to this is emergency rescue operations. In particular, the 119 First Aid system serves as a crucial institution responsible for the hospital transportation of emergency patients. However, rescue personnel still encounter cases of interference with their activities during their duties. Despite efforts from the police, these interference cases persist, and they share similarities with the crime of obstructing official duties. Interference with emergency activities exhibits a comparable nature to instances such as physical assaults and equipment damage against emergency medical practitioners working within the emergency medical system. Therefore, a comprehensive understanding and improvement efforts regarding the issues of interference that arise during the process of emergency medical activities, including the 119 First Aid system, are necessary. The solution to these problems is to establish and improve the conditions for obstruction of first aid activities, focusing on the "Framework Act on Firefighting" and the "Act on 119 Rescue and Emergency."

• Journal of Service Research and Studies
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• v.14 no.1
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• pp.1-12
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• 2024

As the service robot market grows among the food technology industry, the quality of robot service that affects consumer behavioral intentions in the restaurant industry has become important. Serving robots, which are common in restaurants, reduce employee work through order and delivery, but because they do not respond to service failures, they increase customer dissatisfaction as well as increase employee work. In order to improve the quality of service beyond the simple function of receiving and serving orders, functions of recovery effort, fairness, empathy, responsiveness, and certainty of the process after service failure, such as serving employees, are also required. Accordingly, we assumed the type of failure of restaurant serving service as two internal and external factors, and developed a serving robot with a vocational ethics module to respond with a professional ethical attitude when the restaurant serving service fails. At this time, the expression and action of the serving robot were developed by adding a failure mode reflecting failure recovery efforts and empathy to the normal service mode. And by recruiting college students, we tested whether the service robot's response to two types of service failures had a significant effect on evaluating the robot. Participants responded that they were more uncomfortable with service failures caused by other customers' mistakes than robot mistakes, and that the serving robot's professional ethical empathy and response were appropriate. In addition, unlike the robot's favorability, the evaluation of the safety of the robot had a significant difference depending on whether or not a professional ethical empathy module was installed. A professional ethical empathy response module for natural service failure recovery using generative artificial intelligence should be developed and mounted, and the domestic serving robot industry and market are expected to grow more rapidly if the Korean serving robot certification system is introduced.

• Steel and Composite Structures
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• v.50 no.6
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• pp.705-720
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• 2024

Analyzing the collapse behavior of thin-walled steel structures holds significant importance in ensuring their safety and longevity. Geometric imperfections present on the surface of metal materials can diminish both the durability and mechanical integrity of steel shells. These imperfections, encompassing local geometric irregularities and deformations such as holes, cavities, notches, and cracks localized in specific regions of the shell surface, play a pivotal role in the assessment. They can induce stress concentration within the structure, thereby influencing its susceptibility to buckling. The intricate relationship between the buckling behavior of these structures and such imperfections is multifaceted, contingent upon a variety of factors. The buckling analysis of thin-walled steel shell structures, similar to other steel structures, commonly involves the determination of crucial material properties, including elastic modulus, shear modulus, tensile strength, and fracture toughness. An established method involves the emulation of distributed geometric imperfections, utilizing real test specimen data as a basis. This approach allows for the accurate representation and assessment of the diversity and distribution of imperfections encountered in real-world scenarios. Utilizing defect data obtained from actual test samples enhances the model's realism and applicability. The sizes and configurations of these defects are employed as inputs in the modeling process, aiding in the prediction of structural behavior. It's worth noting that there is a dearth of experimental studies addressing the influence of geometric defects on the buckling behavior of cylindrical steel shells. In this particular study, samples featuring geometric imperfections were subjected to experimental buckling tests. These same samples were also modeled using Finite Element Analysis (FEM), with results corroborating the experimental findings. Furthermore, the initial geometrical imperfections were measured using digital image correlation (DIC) techniques. In this way, the response of the test specimens can be estimated accurately by applying the initial imperfections to FE models. After validation of the test results with FEA, a numerical parametric study was conducted to develop more generalized design recommendations for the stainless-steel shell structures with the initial geometric imperfection. While the load-carrying capacity of samples with perfect surfaces was up to 140 kN, the load-carrying capacity of samples with 4 mm defects was around 130 kN. Likewise, while the load carrying capacity of samples with 10 mm defects was around 125 kN, the load carrying capacity of samples with 14 mm defects was measured around 120 kN.

• The Journal of Korean Medicine
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• v.44 no.4
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• pp.41-58
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• 2023

Objectives: This retrospective observational study aimed to investigate the efficacy and safety of Cheongpebaedok-tang, a traditional Korean herbal medicine, provided via telemedicine to patients with asymptomatic to mild COVID-19 in Korea. Methods: From February to April 2020, a retrospective analysis investigated COVID-19 patients treated via Korean telemedicine. The study involved asymptomatic to mild cases receiving Cheongpebaedok-tang more than three times, along with continuous Korean medicine care in convalescence. Diagnoses and treatment adhered to the telemedicine guidelines of the Association of Korean Medicine, with varied Cheongpebaedok-tang prescriptions based on symptom severity. Symptom evaluation involved a detailed assessment using a 15-item tool at initial and final sessions. Results: The study included 27 patients, with a mean age of 48.7 ± 2.3 years (mean ± standard error). Patients began self-administering oral Cheongpebaedok-tang for an average of 19.4 ± 1.8 days after the date of COVID-19 diagnosis confirmation and continued the medication for 15.8 ± 1.2 days. The reported side effects of the Cheongpebaedok-tang included palpitations (11.1%), insomnia (7.4%), dizziness (3.7%), and diarrhea (3.7%). All side effects disappeared after adjusting the prescription according to standard treatment guidelines. The occurrence of all COVID-19-related adverse symptoms, except fatigue and myalgia, decreased. Fatigue was the most common chronic symptom persisting after 6 months (51.9%), followed by ocular symptoms (37.0%) and sore throat (22.2%). Conclusions: This study implies Cheongpebaedok-tang may offer a potentially safe, symptom-alleviating approach for managing mild COVID-19 cases via telemedicine, although further comprehensive research is warranted.

• The Journal of Internal Korean Medicine
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• v.45 no.3
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• pp.381-395
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• 2024

Objectives: The main purpose of this study is to investigate the clinical characteristics of patients complaining of indigestion after COVID-19 infection (CI) or COVID-19 vaccination (CV) and to confirm the effectiveness and safety of Korean medical treatment. Methods: We retrospectively collected and investigated the medical records of 39 patients admitted to the Kyung Hee University Korean Medicine Hospital with a chief complaint of dyspepsia from January 1, 2020 to February 29, 2024 who reported the onset or significant exacerbation of dyspepsia after CV or CI. Patients were divided into vaccination and infection groups, and their demographic characteristics, Ryodoraku results, presenting symptoms, traditional Korean medicine treatments, and treatment outcomes were analyzed. Results: When comparing the groups with dyspepsia after CV and after CI, it was observed that the CI group had significantly lower average body weight, and the measurements of LH6, LF1, and LF6 in the Ryodoraku test were significantly lower. Additionally, compared to the CV group, the CI group showed significantly more abdominal distension, nausea, and abdominal pain. Significant relief of upper gastrointestinal symptoms was observed in both the CV and CI groups after treatment. No adverse reactions were observed during the course of treatment. Conclusion: The CI group tended to complain more severely of various dyspeptic symptoms and had a tendency to lower body weight than the CV group, as was also reflected in the results of the Ryodoraku test. Korean medical treatment can be effective and safe in treating these patients.

• The Korean journal of internal medicine
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• v.39 no.3
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• pp.458-468
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• 2024

Background/Aims: The SAMe-TT₂R₂ score is used for assessing anticoagulation control (AC) quality with warfarin. However, it is hard to apply SAMe-TT₂R₂ score in Asian patients with atrial fibrillation (AF), because it has not been proven in those populations. This study aimed to validate the SAMe-TT₂R₂ score in Asian patients with AF and suggest a modified SAMe-TT₂R₂ score for this population. Methods: We analyzed 710 Korean patients with AF who were using warfarin. The AC quality was assessed as the mean time in therapeutic range (TTR). Each component of SAMe-TT₂R₂ score was evaluated for the relationship with AC. Further clinical factors that predict AC were analyzed. Identified factors were re-assorted and constructed as SA₂Me-TTR scoring system. Results: Of the components of the SAMe-TT₂R₂ score, female, age, and rhythm control were associated with AC. Heart failure and renal insufficiency were newly identified factors associated with AC. The modified SA₂Me-TTR score was reconstructed with the relevant risk factors (S, female gender, 1 point; A, age < 60 yr, 2 points; Me, medical history of heart failure, 1 point; T, treatment for rhythm control, 1 point; T, history of stroke or transient ischemic attack, 1 point; R, renal insufficiency, 1 point). The modified SA₂Me-TTR score demonstrated an excellent relationship with the grading of AC. The modified SA₂Me-TTR score ≤ 1 identified patients with good AC (hazard ratio 2.46, 95% CI 1.75-3.47). Conclusions: The modified SA₂Me-TTR score was useful for guiding oral anticoagulants selection in Asian patients with AF.

• Nuclear Engineering and Technology
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• v.56 no.5
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• pp.1925-1931
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• 2024

The study conducted in the northwest region of Jordan aimed to assess the levels of natural radioactivity in soil and olive mill pomace (OMP) samples. The researchers used Nal (TI) gamma-ray spectrometry to measure the activity concentrations of ²²⁶Ra, ²³²Th, ⁴⁰K, and ¹³⁷Cs in the samples. The average activity concentrations of ²²⁶Ra, ²³²Th, ⁴⁰K, and ¹³⁷Cs in the soil samples were found to be 18.624 ± 5.82, 12.276 ± 5.728, 518.33 ± 212.57, and 0.140 ± 0.09 (Bq, kg^-1), respectively. In the OMP samples, the average activity concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰K were 7.272 ± 4.386, 3.454 ± 1.503, and 169.997 ± 81.873 (Bq kg^-1), respectively, and no ¹³⁷Cs was detected. The study also investigated fundamental parameters associated with radon, specifically the radon emanation coefficient (Rn_EC) and radon mass exhalation rate (E_x). The Rn_EC values ranged from 0.621 to 0.78 (Bq kg^-1), with an average value of 0.71 ± 0.06 (Bq kg^-1). The estimated E_x from the soil samples ranged from 65.83 to 124.86 (mBq kg^-1h^-1), with an average value of 99.74 ± 21.73 (mBq kg^-1h^-1). Regarding radiological hazards, the study examined various parameters, including radium equivalent activity, external and internal hazard indices, gamma and alpha indices, absorbed gamma dose rate, and excess lifetime cancer risk. All of these assessed values were found to be below the worldwide recommended limits for radiological safety. Additionally, the study analyzed the concentrations of gross alpha and gross beta radioactivities in soil and OMP samples. The soil samples had an average gross alpha activity of 4.642 ± 1.04 (Bq kg^-1) and an average gross beta activity of 48.13 ± 14.50 (Bq kg^-1). The OMP samples showed an average gross alpha activity of 0.32 ± 0.27 (Bq kg^-1) and an average gross beta activity of 59.19 ± 12.94 (Bq kg^-1). Overall, the obtained results are crucial for evaluating the radiological risks associated with natural radioactivity in the northwest region of Jordan. The findings establish baseline data for comparison and reference for radioactivity levels in the environment.