• Journal of the Korean Society for Precision Engineering
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• 제13권7호
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• pp.158-166
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• 1996

In this study, a flexible disk grinding process is applied in order to produce high precision product. A new model was developed considering feed motion along horizontal and vertical direction. Different types of feed speed variation was tested with respect to distinct process stages in order to achieve flat surface. It was observed that highest order polynomial form for both horizontal and vertical feed speed variation among the proposed categories produced surface close to flat one. Disk deflection trend during the process was visualized confirming the proposed scheme. Cutting force and VRR(volume removal rate) was observed as an aid to process planning.

• Journal of Biosystems Engineering
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• 제33권6호
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• pp.453-461
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• 2008

This study was conducted to develop a root-removed splice grafting system for cucurbitaceous vegetables, mainly watermelon and cucumber seedlings, for the seedlings factories where currently most of seedlings grafting works are carried out by manual works. The major results of the study are as follows. The dimensions of rootstocks and scions, except cotyledon width, of root- removed splice grafting of watermelon and cucumber were shown to be varied within the 2.5-fold range. The growth status of seedlings were not consistent in terms of cotyledon sprouting direction and angle which were considered as one of the important factors for in root-removed splice grafting. The grafting work of root-removed splice for grafted watermelon and cucumber could be divided by four sub-operations: seedling supplying, cutting, clipping and potting, while a part or all root of the rootstock was removed in the seedlings supplying operation. The cutting angles of the rootstock and scion were $34-45^{\circ}$ and $20-45^{\circ}$, respectively, while the stem length of the scion varied from 6 mm to 12 mm. The splices of rootstock and scion were heaped up in parallel and then fixed by a clip. It indicated that the ideal grafting system, adopting conventional grafting processes of seedlings specifications as well as conventionally manual root-removed splice grafting method, performed very well for seedlings gripping and transporting, supplying clip, clipping and discharging grafted seedlings while workers supplied seedlings to the semi-automatical system.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• 제56권3호
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• pp.223-229
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• 2020

We analyzed the cutting mechanism of laver harvesting machine in the sea area near Gooam Port in Goheung, Jeollanam-do, and investigated the change and efficiency of laver collecting operation in the working ship. The laver working ship slides uniformly from the bow to the upper part of the laver collecting machine on the deck and cuts the wet laver attached to the bottom of the net at the blade of the havesting machine. The laver farming net, which was loaded with laver turrets on the deck by gravity and collected primitives, consisted of a ship structure that led to the stern side and into the sea. The working ship operation is in harvesting process while driving in a S-shape that is separated by one space to efficiently collect the laver net. During laver working ship operation, the speed was 0.51 m/s in the access stage, 0.56 m/s in the havesting stage, and 0.52 m/s in the exit stage. Considering the cutting edge life and production efficiency of the laver harvesting machine, it is appropriate to harvest 1.15 to 1.26 kg/rpm by operating at a rotational speed of about 700 to 800 rpm rather than forcibly harvesting the product at high speed. On the deck of the working ship, 959.7 kg of starboard and 1048.7 kg of center were 964.7 kg of port side. Based on the starboard, 9.3% of the central part and 0.5% of the port side appeared. The reason for this was due to the difference in harvest time according to the turning direction of the working ship.

• Journal of the military operations research society of Korea
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• 제36권1호
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• pp.103-121
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• 2010

As a cutting edge technology intensive value-added business, the defense industry is jumping into a new engine of a national growth. Also, the defense industry export is recognized not only as the field to activate the Korean economy but also as an important field to create the national brand value. However, though the consensus on the importance of defense industry export helps achieve the remarkable performance in reality, the rate of increase in the budget for national defence is slowing down gradually, and the investment in R&D is not so big, and there are a lot of drawbacks with the management of core technology and the development of cutting edge weapon system. Accordingly, this thesis tried to find the leverage to make the structure of defense industry export work normally after analyzing the systematical structure of defense industry export to understand its characteristics. Also, through the process to make the leverage a strategy, the thesis tried to present the optimal direction of policy to join the ranks of the advanced countries in defense industry export.

• Journal of architectural history
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• 제15권2호
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• pp.23-38
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• 2006

During the repair and restoration of the Daewoongjeon Hall of Youngguksa Temple, species identification and tree-ring dating for both present wood elements and charred ones excavated under the Hall, were conducted. The species of 74 wood elements of Daewoongjeon Hall, were identified as Pinus densiflora Sieb. et Zucc. and only 1 was identified as exotic Pinus species. The latter wood, which was used in the laths, seems to have been replaced during past repairs. Many documentary records and various artifacts pertaining to Youngguksa Temple are being excavated, but none described precisely the construction date of the present Daewoongjeon Hall. Also, from beneath the Daewoongjeon Hall, cornerstone and foundation of previous building and several charred wood elements were excavated. In comparing the direction of the stone columns of foundation of the previous structure and the existing Daewoongjeon Hall, the previous structure was rotated in an angle of approximately $15^{\circ}$. Therefore, in order to find the association of the previous structure with the present Daewoongjeon Hall, tree-ring dating was conducted. The dating of 41 original timbers and 14 roof-filling timbers of the present construction elements revealed that the last annual ring was of A. D. 1703 with complete latewood, indicating that those woods was cut some time between the autumn of 1703 and spring of 1704, and the building was erected in 1704 when we assume no period of wood storage. The year of the last annual ring of the charred elements, which were excavated from beneath the Daewoongjeon Hall, was analyzed as 1674. The cutting year of the woods used for the present building began in 1698, therefore, it can be presumed that the Daewoongjeon Hall before the fire was a structure that was elected shortly after 1674 and that a catastrophic fire occurred some time between 1674 and 1698.

• Journal of the FoodService Safety
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• 제2권2호
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• pp.59-66
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• 2021

The results of the inspection based on the sanitation checklist and the measurement of refrigerator/freezer temperature, illuminance, and ATP were conducted at 12 school foodservices in Daiyue-district, Taian-city, Shandong Province, China, at the same time, and the results were as follows. Five items of 'Use sterilized cutting boards', 'Use sterilized knives', 'Use worktable after sterilization', 'Use sink after sterilization', 'Sterilize the interior/exterior of the refrigerator regularly' in the checklist inspection were found not to be performed (0%). Two items of 'Disinfect hands after washing', 'Equipped with hand sterilizer' and 'Sterilize the kitchen areas regularly' were investigated as being performed only in one foodservice (8%). The average illuminance of the receiving stand were 373.08±106.35 Lux, 8% when the standard (540 Lux or higher) was complied with, the average refrigerator temperature were 7.06±0.82℃, 38.9% when the standard (-2 to 5℃) was observed 8% of cases complying with the standard (below -18℃) at -8.56±0.76℃ were investigated. As a result of ATP measurement, the surfaces of knife edge, cutting board, refrigerator door handle, worktable, and sink, which are not sterilized at all, were not suitable (accept ratio 0%), sterilized food plate (accept ratio 54.2%) and utensil for preserved food (accept ratio 75%) had a relatively high accept ratio. China's hygiene regulations should be revised in the direction of strengthening disinfection practices for facilities, equipment, and the environment, and hygiene measures such as education on disinfection and preparation of economical disinfection methods should be established.

• Journal of Veterinary Clinics
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• 제30권6호
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• pp.490-495
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• 2013

A 9-year old, castrated male Pekingese dog weighing 6.9 kg was referred with one week history of dyspnea, depression, yellow vomiting and abdominal distension. Refractory right lung field opacity was diagnosed as spontaneous right cranial lung lobe torsion (LLT) with collapsed middle lobe on the computed tomography. Four days after diagnosis, right fourth intercostal thoracotomy was performed under propofol-remifentanil based total intravenous anesthesia (TIVA). Right cranial and middle lung lobes were twisted together in a clockwise direction. ENDOPATH-ETS-FLEX-45, an articulating endoscopic linear cutting stapler was applied at the hilus and there were no complications after resection. The patient recovered favorably and has been doing well up to one year follow up. Lung lobe torsion is an uncommon condition in small breed dogs, this case report suggests serial lung lobe torsion of cranial lobe followed by middle lobe in small breed dog, and immediately after diagnosis surgical intervention is beneficial to prevent progression of LLT. Furthermore, using self cutting stapling device and TIVA technique will be helpful for lung lobectomy in dogs.

• Transactions of the Korean Society of Mechanical Engineers
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• 제9권5호
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• pp.590-597
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• 1985

A recursive geometric adaptive control method to compensate for machining straightness error in the finished surface due to tool deflection and guideway error generated by end milling process is developed. The relationship between the tool deflection and the feedrate is modeled by a modified Taylor's tool life equation. Without a priori knowledge on the variations off cutting parameters, time varying parameters are then estimated by an exponentially windowed recursive least squares method with only post-process measurements of the straightness error. The location error is controlled by shifting the milling bed in the direction perpendicular to the finished surface and adding a certain amount of feedrate with respect to the tool deflection model before cutting. The waviness error is compensated by adjusting the feedrate during machining. Experimental results show that location error is controlled within a range of fixturing error of the bed on the guideway and that about 60% reduction in the waviness error can be achieved within a few steps of parameter adaption under wide operating ranges of cutting conditions even if the parameters do not converge to fixed values.

• Journal of Biosystems Engineering
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• 제41권4호
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• pp.288-293
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• 2016

Purpose: The purpose of this study was to investigate the key factors in designing a three-wheeled two-row soybean reaper (riding type) that is suitable for soybean production, and ensure worker safety by proposing optimal work conditions for the prototype of the designed machine in relation to the slope of the road. Methods: A three-wheeled two-row soybean reaper (riding type) was designed and its prototype was fabricated based on the local soybean-production approach. This approach was considered to be closely related to the prototype-designing of the cutter and the wheel driving system of the reaper. Load distribution on the wheels of the prototype, its minimum turning radius, static lateral overturning angle, tilt angle during driving, and The working and rear overturning (back flip) angle were measured. Based on the gathered information, investigations were conducted regarding optimal work conditions for the prototype. The investigations took into account driving stability and worker safety. Results: The minimum ground clearance of the prototype was 0.5 m. The blade height of the prototype was adjusted such that the cutter was operated in line with the height of the ridges. The load distribution on the prototype's wheels was found to be 1 (front wheel: F): 1.35 (rear-left wheel: RL): 1.43 (rear-right wheel: RR). With the ratio of load distribution between the RL and RR wheels being 1: 1.05, the left-to-right lateral loads were found to be well-balanced. The minimum turning radius of the prototype was 2.0 m. Such a small turning radius was considered to be beneficial for cutting work on small-scale fields. The sliding of the prototype started at $25^{\circ}$, and its lateral overturning started at $39.3^{\circ}$. Further, the critical slope angle for the worker to drive the prototype in the direction of the contour line on an incline was found to be $12.8^{\circ}$, and the safe angle of slope for the cutting was measured to be less than $6^{\circ}$. The critical angle of slope that allowed for work was found to be $10^{\circ}$, at which point the prototype would overturn backward when given impact forces of 1,060 N on its front wheel. Conclusions: It was determined that farmers using the prototype would be able to work safely in most soybean production areas, provided that they complied with safe working conditions during driving and cutting.

• The Journal of the Convergence on Culture Technology
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• 제8권2호
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• pp.367-372
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• 2022

With the recent advent of the New Normal era, realistic technologies and non-contact technologies are receiving social attention. However, the hair styling field focuses on the direction of the hair itself, individual movements, and modeling, focusing on hair simulation. In order to create an improved practice environment and demand of the times, this study proposed a non-contact hair styling VR system. In the theoretical review, we studied the existing cases of hair cut research. Existing haircut-related research tend to be mainly focused on force-based feedback. Research on the interactive haircut work in the virtual environment as addressed in this paper has not been done yet. VR controllers capable of finger tracking the movements necessary for beauty enable selection, cutting, and rotation of beauty tools, and built a non-contact collaboration environment. As a result, we conducted two experiments for interactive hair cutting in VR. First, it is a haircut operation for synchronization using finger tracking and holding hook animation. We made position correction for accurate motion. Second, it is a real-time interactive cutting operation in a multi-user virtual collaboration environment. This made it possible for instructors and learners to communicate with each other through VR HMD built-in microphones and Photon Voice in non-contact situations.