• Journal of the Society of Naval Architects of Korea
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• v.45 no.3
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• pp.247-257
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• 2008

In this paper, a free running system, which is developed recently for a 2m-class ship models, will be introduced. For the remote control of hardware, GUI of software packages was developed using Visual Basic 6.0, and Host PC with Positioning Board manages Servo drive. Then the drive operates propeller and rudder. Its control performance will be shown. Also its adaptability to the resistance, manoeuverability and seakeeping model tests will be considered through the installation on a KTTC standard ship model from MOERI.

• Journal of the Korean Dietetic Association
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• v.27 no.1
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• pp.26-34
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• 2021

This study investigates perception of the free school meal program, satisfaction of school meal, and eating habits of free and paid school meal program students in the Busan area. Between 20 to May 2020, a total of 350 students were researched, of which 177 belonged to the second grade of high school (free school meal program), and 173 were from the third grade of high school (paid school meal program). 96.0% free school meal program students and 89.0% paid school meal program students responded to the necessity of a free school meal program, which was significantly different between the two groups (P<0.05). All questions regarding the perception of the free school meal program, which were responded to by more than 3 points, were considered positive. 'Decline of the school meal's quality' had the maximum response, from 64.4% and 76.4% free and paid school meal program students, respectively, and was significantly different between groups (P<0.05). Paid school meal program students wasted significantly more school food than the free school meal program students (P<0.001). 'Not delicious' was responded by 56.0% free school meal program students and 50.0% paid school meal program students. Evaluating satisfaction of the food quality and service categories was determined to be higher amongst free school meal program students than the paid school meal program students (P<0.05). Considering our study data, we propose that with the gradual expension of free school meal programs, inclusion as part of the education system will serve as a foundation for proper eating habits, and compulsory education will help improve students' health and quality of life.

• Honam Mathematical Journal
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• v.28 no.4
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• pp.499-511
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• 2006

It is well-known that every finitely generated torsion-free module over a principal ideal domain is free. This will be generalized. We deal with ideals of the finite, external direct product of certain rings. Finally, if M is a torsion-free, finitely generated module over a reduced, Noetherian ring A, then we prove that Ms is a projective module over As, where $S=A{\setminus}(A)$.

• Archives of Reconstructive Microsurgery
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• v.21 no.1
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• pp.76-80
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• 2012

Various soft tissue defects can be occurred in the hand. In determining the most suitable means of reconstruction a defect, the benefit of the reconstruction has to outweigh the risk of donor morbidity. Flap selection will be based on the size of the defect, the requirements for sensibility, the surgeon's comfort level, and the patient profile such as gender, age, or systemic disease. The hand is the most important tactile sensory organ, hence sensory restoration is critical. Neurosensory free flaps can provide sensibility, vascularity, and soft tissue coverage to an injured hand. This paper will discuss free flaps which can be used for soft tissue reconstruction of the hand.

• Journal of Chest Surgery
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• v.22 no.1
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• pp.10-15
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• 1989

Excision of bullous emphysema or decortication of chronic empyema commonly results in a prolonged air leakage. Prolonged air leakage requires prolonged intercostal drainage, delays recovery, and can be followed complications such as pneumothorax, atelectasis, incomplete expansion of remained lung, secondary infection. To minimize these complications free muscle grafts can be used like a patch to close the opening of visceral pleura and reinforce suture lines without undue tension. From a preliminary study using the latissimus dorsi muscle as a free muscle graft in the rabbit pleural space, viable muscle fibers that seems the result of the process of regeneration can be consistently identified around the degenerating muscle fibers. Voluminous connective tissues and numerous blood vessels are also observed in the peripheral zone. Further studies in that free muscle graft will be sutured with visceral pleura and lung parenchyme will hopefully provide additional information before clinical application.

• Journal of the Korean Home Economics Association
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• v.33 no.3
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• pp.255-264
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• 1995

This study was the designed to measure skin irritation caused by clothing at free foraldehde have caused a substantial number of cases of dermatitis type. Free formaldehyde levels were observed in infant's sanitatized goods9disposable diapers, cotton-diapers and under wear etc.) at 1992, 1994. The amount of free formaldehyde was measured by means of Acetyle Acetone method(KS K 0611). As the resort, underwear generally gave the highest free formaldehyde level, but disposable diapers and cotton diapers showed the lowest level. The formaldehyde level in intan's clothing lowered in 1994 than 1992, after the enforcement of the level in intant's clothing lowered in 1994 than 1992, after the enforcement of the formaldehyde level control. it was found that 38.7% of infant's sanitatized goods still exceeded th controlled level(A-Ao : 0.05) In the future, research to lower the amount of formaldehyde released form fabrics will also lead to decreased incidence of garment formaldehyde sensitivity. The possibility of a consumer suffering is being in convenienced form a textile-related skin problem will be even lower than it has been in the past.

• Journal of Navigation and Port Research
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• v.33 no.9
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• pp.603-608
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• 2009

In this paper, a 3m-class free running model ship will be introduced with its manoeuvring performance experiments. The results of turning circle test and zig-zag test will be explained. The developed system are equipped with GPS, main control computer, wireless LAN, IMU (Inertial Measurement Unit), self-propulsion propeller and driving rudder. Its motion can be controlled by RC (Radio Control) and wireless LAN from land based center. Automatic navigation is also available by pre-programmed algorithm. The trajectory of navigation can be acquired by GPS and it provides us with important data for ship's motion control experiments. The results of manoeuvring performance experiment have shown that the developed free running model ship can be used to verify the test of turning circle and zig-zag. For next step, other experimental researches such as ship collision avoidance system and automatic berthing can be considered in the future.

• Journal of Sensor Science and Technology
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• v.19 no.6
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• pp.403-420
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• 2010

Nano and micro structure-based biosensors are promising tool for label-free detection of biomolecular interactions with great accuracy. This review gives a brief survey on nano and micro platforms to sense a variety of analytes such as DNA, proteins and viruses. Among incredible nano and micro structure for bio-analytical applications, the scope of this paper will be limited to micro and nano resonators and nanowire field-effect transistors. Nanomechanical motion of the resonators transducers biological information to readable signals. They are commonly combined with an optical, capacitive or piezo-resistive detection systems. Binding of target molecule to the modified surface of nanowire modulates the current of the nanowire through electrical field-effect. Both detection methods have advantages of label-free, real-time and high sensitive detection. These structures can be extended to fabricate array-type sensors for multiplexed detection and high-throughput analysis. The biosensors based on these structures will be applied to lab-on-a-chip platforms and point-of-care diagnostics. Basic concepts including detection mechanisms and trends in their fields will be covered in this review.

• Journal of the Korea Convergence Society
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• v.11 no.5
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• pp.209-217
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• 2020

The background of the research is the following. With the prosperity of drone industry, the government has been actively promoting measures to nominate 'drone photographing free areas'. However, existing laws, and procedures are rather unclear with related environmental factors in discordance with one another. Hence, voices in need for establishing a clear precondition for nominating drone photography free area have been rising. The purpose of the research is to provide measures for the preconditions to establish photography free areas for convenient drone photographing. The research utilizes literary methods, conducting focus group interviews to coordinate with specialists who can participate and discuss so that they can provide improvement measures. The research renders improvement measures in different sectors including 2x items in aviation security law, 8x items in free area nomination and procedure, 4x items in infrastructure establishment and information management area. The expected effects are the following: by attaching drone photography with aviation security law, nominating photography free area can be linked up with the Ministry of Land Infrastructure and Technology. Secondly, by enlarging photography restricted area to upper mid-air, a three dimensional drone security will be possible. Thirdly, by providing a 'Yongin area standard model', free area nomination will become more easy. Future research will focus on enhancing aviation security law regarding drone photographing. In addition, the promotion to nominate free areas for 33x responsible areas in accordance with the National Intelligence service will be required.

• Bulletin of the Society of Naval Architects of Korea
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• v.19 no.2
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• pp.13-18
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• 1982

The method of Rankine source distribution is emerging as a powerful yet simple alternative for the solution of complicated free surface problems. But it has been uncertain whether the radiation condition could be satisfied exactly by distributing the simple sources on the free surface only. In this paper, it is proved rigorously that the Rankine sources, whose intensities are varying sinusoidally along the axis satisfying the free surface boundary condition, generate the radiation waves both in the infinite and finite-depth flows. A formula is derived to give the upper and lower bounds of the errors in the induced velocity computation that will be introduced by truncating the extent of source distribution on the free surface. Since the truncation is inevitable in the numerical analysis, this formula may be used as a criterion to limit the position of the field points, where velocity computation is made, away from the truncation boundary. A typical analysis shows that the maximum error will be 3.4 percent of the exact induced velocity when the field point is on the free surface two wave lengths away from the truncation boundary.