• Korean Journal of Construction Engineering and Management
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• v.24 no.2
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• pp.13-23
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• 2023

Unlike building construction projects, where the activity is repeatedly carried out in a limited area, civil engineering projects such as roads and railroads are carried out in a linear type in a horizontal working space over several tens of kilometers. Each activity is managed with a station number that has a unit of distance from the starting point to the end point. For this reason, since the work location information of the activity is a major management factor, the Gantt chart system that expresses only schedule information may have limitations. In this study, authors propose a method for constructing a linear schedule chart that can simultaneously express schedule information indicating the start and finish dates and location information indicating the start and end positions of each activity, and develop a system for generating a linear schedule chart. In the study, the coordinate axes of the linear schedule chart consisted of distance and date values on the X and Y axes, respectively, and each activity was expressed as a symbol that can infer the type of work to increase the visibility of the linear schedule chart compared to the simple bar chart method. The linear schedule chart generation system was reviewed for practical applicability by utilizing the actual schedule data of bridge structures in a railroad project.

• The Journal of the Acoustical Society of Korea
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• v.42 no.4
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• pp.320-328
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• 2023

Underwater active target detection is vital for defense systems, requiring accurate detection and estimation of distance and velocity. Sequential transmission is necessary at each beam angle, but divided pulse length leads to range ambiguity. Multi-frequency transmission results in time-bandwidth product losses when bandwidth is divided. To overcome these problem, we propose a novel method using Generalized Sinusoidal Frequency Modulation (GSFM) for rapid target detection, enabling low-correlation pulses between subpulses without bandwidth division. The proposed method allows for rapid updates of the distance and velocity of target by employing GSFM with minimized pulse length. To evaluate our method, we simulated an underwater environment with reverberation. In the simulation, a linear frequency modulation of 0.05 s caused an average distance estimation error of 50 % and a velocity estimation error of 103 % due to limited frequency band. In contrast, GSFM accurately and quickly tracked targets with distance and velocity estimation errors of 10 % and 14 %, respectively, even with pulses of the same length. Furthermore, GSFM provided approximate azimuth information by transmitting highly orthogonal subpulses for each azimuth.

• The Journal of the Acoustical Society of Korea
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• v.43 no.2
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• pp.214-224
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• 2024

Sonobuoys are disposable devices that utilize sound waves for information gathering, detecting engine noises, and capturing various acoustic characteristics. They play a crucial role in accurately detecting underwater targets, making them effective detection systems in anti-submarine warfare. Existing sonobuoy deployment methods in multistatic systems often rely on fixed patterns or heuristic-based rules, lacking efficiency in terms of the number of sonobuoys deployed and operational time due to the unpredictable mobility of the underwater targets. Thus, this paper proposes an optimal sonobuoy placement strategy for Unmanned Aerial Vehicles (UAVs) to overcome the limitations of conventional sonobuoy deployment methods. The proposed approach utilizes reinforcement learning in a simulation-based experimental environment that considers the movements of the underwater targets. The Unity ML-Agents framework is employed, and the Proximal Policy Optimization (PPO) algorithm is utilized for UAV learning in a virtual operational environment with real-time interactions. The reward function is designed to consider the number of sonobuoys deployed and the cost associated with sound sources and receivers, enabling effective learning. The proposed reinforcement learning-based deployment strategy compared to the conventional sonobuoy deployment methods in the same experimental environment demonstrates superior performance in terms of detection success rate, deployed sonobuoy count, and operational time.

• Science of Emotion and Sensibility
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• v.9 no.1
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• pp.49-61
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• 2006

The present mobile phone industry has significant effect on the domestic economy and has taken root as the core item that has the responsibility to lead the Korean economy for a considerable period of time. As the mobile phone market becomes gigantic, the mobile phone is being used by people in broader age bracket, and functions or designs preferred by people of various age are getting more diverse. Like that, as the mobile phone has greater effect on and meaning in our daily lives, consumers of mobile phone have growing expectation of the mobile phone Now, the core function of voice communication via the mobile phone is not a great concern to consumers. But the function, such as more convenient and friendly information input and output, processing and storage, and the design, which is more sophisticated and optimized for the user environment, are being demanded, not just the simple voice communication. And as the modern design is getting more similar to the objects of traditional high art consumed by consumers every day, the aesthetic aspect of design can play an important role, as the factor that differentiates the product, in creating new value which forms the spiritual and emotional value of human beings to improve the quality of living, and in addition, the willingness of consumers to buy is determined by the design that they prefer the most. Like that, a new design of mobile phone based on a new dimension and preferred by the consumers the most is urgently required to be developed by shedding light on the factors related to the preference of consumers on the basis of the analysis on the aesthetic aspect, which can be said to be the most critical factor in the design process. Therefore, this study aims to identity the common preference and different factors of aesthetic aspects through the analysis on the aesthetic aspects of the mobile phone preferred by users among countries, and figure out the formative artistic factors of aesthetic aspects that are considered to be important, in order to propose the guideline on the aesthetic aspect of mobile phone that can be applied to the design of mobile phone practically.

• Science of Emotion and Sensibility
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• v.21 no.2
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• pp.101-112
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• 2018

This study was carried out to enhance the competitiveness of blackbox design for domestic and international companies, based on the explosive growth of the blackbox market due to development of blackbox design for vehicle accident prevention and post-treatment. In the past, the blackbox market has produced products indiscriminately to meet the ever-increasing demand of consumers. Therefore, we thought a new design method was necessary to effectively investigate the needs of rapidly changing consumers. In this study, we aimed to identify the best-selling blackbox to understand the design flow, and the optimum area for a blackbox, considering the uniqueness of associated vehicle. Based on discussion with blackbox design experts, we studied the direction of design and the problems with blackbox use, which were reflected in blackbox development. Through this research, two types of design - leading blackbox (A type) and mass production blackbox (B type) - were proposed for compatibility of the blackbox with the car. The leading type of blackbox was positioned so that it was wrapped with the room mirror hinge before the screw was fastened, in order to achieve an integrated design. Therefore, we designed an integrated form and resolved the placement problem of an adhesive blackbox. To blend, the mass production blackbox implemented material and surface processing in the same way with the car, and adopted the slide structure to automatically turn off the main body power when removing the SDcard, reflecting consumer needs. This study considers evolving consumer needs through a case study and collective intelligence and deals with implementation of the whole design process during mass production. In this study, we aimed to strengthen the competitiveness of the blackbox design based on design method and its realization.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.299-308
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• 2001

We examined the growth variation with water depth, interval between suspended lines and locality of seedling production of sea squirt. Halocpthia roretzi, measuring approximately $10.1\~15.3$ mm in tunic height, was cultured at the farm near Guryongpo, Pohang city from 7 January to 6 December 1998 (333 days). Growth condition depending on culture depth was most favourable at the depth of $10\~12$m, It was concluded that nutritional conditions were better at the depth since there was a greater mount of phytoplankton than at any other depth in the water column. Growth condition depending on distance between suspended lines was most favourable at the interval of 2 m and 2.5 m than at the interval of t m and 1.5 m, There was no significance difference in growth variation with locality of seedling. The seasonal variations in growth of tunic height, meat and total weight were correlated with temperature and chlorophyll a, In the depth of $10\~12m$ the rate of increase in tunic height was generally greatest in the growth period II ($244{\mu}m/day$) and IV ($338{\mu}m/day$), lower in the period I ($108{\mu}m/day$), and slightly increased during the period III ($185{\mu}m/day$). The water column have showed a typical seasonal pattern with temperature ranged between $12.07{\sim}24.14^{\circ}C$ and over $20^{\circ}C$ between July and September.

• Journal of Oral Medicine and Pain
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• v.35 no.1
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• pp.31-39
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• 2010

This study is to observe the bacteriocidal effect of the Low Level Laser (LLL) against oral microorganisms which are related to the occurrence of periodontal diseases and oral malodors. The Porphyromonas gingivalis 2561 (P. gingivalis 2561) and Prevotella intermedia (Pr. intermedia) were treated with photosensitizing substance-toluidine blue O (TBO; C.I. 52040) and then radiated with the LLL which has 650nm wavelength for 1, 2, 3 and 5mins. continuously upon varying distances of 1, 2 and 3cm for each experimental groups. The results are as follows; 1. The P. gingivalis 2561 which was treated with TBO and then radiated with LLL at a distance of 3cm for 1min. showed 99.99% higher antibacterial effect in comparison to the experimental group treated only with TBO. 2. The Pr. intermedia which was treated with TBO and then radiated with LLL at a distance of 3cm for 1min. showed 99.8% higher antibacterial effect in comparison to the experimental group treated only with TBO. 3. The bacteriocidal effect of the P. gingivalis 2561 treated with TBO was found to gradually increase as the radiation time of LLL extended from 1min. to 3min. at 1min. intervals. 4. A slight decrease in bacteriocidal effect of the P. gingivalis 2561 was found as the radiation distance of LLL increased from 1cm to 3cm at 1cm intervals. 5. The bacteriocidal effect of the Pr. intermedia was found to slightly decrease as the radiation distance of LLL increased from 1cm to 3cm at 1cm. intervals. As the results shown above suggest, the bacteriocidal effect of LLL was found to increase as the radiation time extended and the distance shortened. Moreover, even the experimental group radiated with LLL at 3cm distance for 1min. which showed the lowest level of bacteriocidal effect, was found to have 99.8% higher bacteriocidal effect than the experimental group which was treated only with TBO and, therefore, this clearly shows the bacteriocidal effect of LLL against oral microorganisms. Thus, the use of LLL is thought to become very useful for suportive treatment for periodontitis and implantitis, and controlling oral malodors as long as it is used within the limits where there is no side effect.

• Journal of Oral Medicine and Pain
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• v.38 no.4
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• pp.339-356
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• 2013

This study was designed to evaluate the sex differences in the pain control effect by morphine injection to masticatory muscle pain patients. Patients with masticatory muscle pain visited the Department of Oral Medicine, Kyung Hee University Dental Hospital were recruited to this study and diagnosed by RDC/TMD. Experimental group were divided into four group each from male (n=20) and female (n=20); saline injection group (n=5), lidocaine injection group (n=5), morphine 1.5 mg injection group (n=5) and morphine 3 mg injection group (n=5). Evaluation list was the subjective pain evaluation(visual analogue scale, Mc Gill pain questionnaire, pain drawing) and the objective pain evaluation(pressure pain threshold, pressure pain tolerance) and evaluation time was injection before, after 1 hour, 24 hour, 48 hour and then it was analyzed statistically. The results were as follows : 1. The male and female were significantly different statistically morphine 3 mg group in visual analogue scale evaluation. (male: p<0.05, female: p<0.05) 2. The male and female were more significantly different statistically morphine 3 mg group than morphine 1.5 mg group in McGill pain questionnaire evaluation. (male: p<0.001, female: p<0.01) 3. The male were significantly different statistically morphine 3 mg group in pain drawing evaluation and pressure pain threshold evaluation. (PD: p<0.001, PPT: p<0.05) Therefore, it was revealed that the morphine 3 mg injection for masticatory muscle pain was effective to pain control male patients and more effect than female patients in the objective pain evaluation.

• Tuberculosis and Respiratory Diseases
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• v.60 no.2
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• pp.160-170
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• 2006

Background : The aberrant promoter hypermethylation of p16INK4a, as a tumor suppressor gene, is contributory factor to non-small cell lung cancer(NSCLC). However, its potential diagnostic impact of lung cancer is unclear. This study measured the level of $p16^{INK4a}$ promoter hypermethylation in the sputum and blood, and compared this with the level measured in the tissue obtained from NSCLC and pulmonary inflammation. Methods : Of the patients who visited the Our Lady of Mercy Hospital in Incheon, Korea for an evaluation of a lung mass and underwent blood, sputum, and tissue tests, 23patients (18 NSCLC, 5 pulmonary inflammation) were enrolled in this study. DNA was extracted from each sample and the level of p16INK4amethylation was determined using methylation-specific polymerase chain reaction. Results : $p16^{INK4a}$ methylation of the blood was observed in 88.9% (16 of 18) and 20.0% (1 of 5) of NSCLC and from pulmonary inflammation samples, respectively (P=0.008). Methylation of the sputum was observed in 83.3% (10 of 12) 80.0% (4 of 5) of NSCLC and pulmonary inflammation samples, respectively (P=1.00). Among the 8 NSCLC tissue samples, methylation changes were detected in 75.0% of samples (6 cases). Four out of seven tissue samples (57.1%) showed concordance, being methylated in both the blood and sputum. Conclusions : There was a higher level of $p16^{INK4a}$ methylation of the blood from NSCLC patients than from pulmonary inflammation. The tissue showed a high concordance with the blood in the NSCLC samples. These findings suggest that $p16^{INK4a}$ promoter hypermethylation of the blood can used to discriminate between NSCLC and pulmonary inflammation.

• Journal of Oral Medicine and Pain
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• v.33 no.1
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• pp.41-48
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• 2008

The focus of this study is to analyze the effect of stress on the health of bruxism patients using the MBTI system. The most common personality type will be identified among the bruxism patients and by understanding their personality & their handling of stress, more comprehesive and effective treatment plan can be constructed. The study will also conclude that the type of personality has big effect on the cause of bruxism, and that this will be considered in the treatment plan in this hospital. The result of the study is as follow. First, more bruxism patients were type I than type E. It can be suggested that this result is due to the introversive people maintaining their energy how within themselves, and private are less to likely to release there stress than the expressive people. Second, among the bruxism patients significantly more type T were found compared to type F. This implies the bruxism tend to follow principals, scientific and analysing during decision making rather than basing their decision an meanings, emotions and influences. Thirdly, more bruxism patients clarified into ST in comparison to non-bruxism patients. This is thought to be due to probable increased stress and anxiety following ST people's tendency to more strict and realistic thinking according to effectiveness, evidence-based and productivity. Fourth, the type IJ was the most of the bruxism patients. We can come to the conclusion that decision-oriented introversion people who have hard to change, a thoroughgoing preparation characters are likely to grind their teeth by their detailed characters. Fifth, the type IT was the most of the bruxism patients. Bruxism patients are usually influenced by spirit, easily hearted, awed of relationship and attention. So, their intensity of stress is much bigger because of their personality. The last, Type IS was the most of the bruxism patients. It means that introvert sensitive types who have characters of calm, passive but defence to other's emotion, also neutral, keep moderation, and have cold-heartedness are likely to grind their teeth frequently. In conclusion it is evident that bruxism patients have particular personality types. Precisive, analysing and introversive bruxism patients are expected to have higher sensitivities to stress.