• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2016.05a
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• pp.20-21
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• 2016

Aids to Navigation (AtoN) is marine traffic safety facility to facilitate the safe and efficient movement of shipping and enhance the protection of the marine environment by the regulation or guideline of The International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA). By IALA NAVGUIDE, the term "New Danger" is defined as newly discovered hazards not yet shown in nautical documents and includes naturally occurring obstructions such as sandbanks or rocks or man-made dangers such as wrecks. 'New Dangers' should be appropriately marked using Lateral, Cardinal, Isolated Danger marks or by using the Emergency Wreck Marking Buoy. However, the Emergency Wreck Marking Buoy has difficulties with implementation conditions in terms of speed and accuracy to install the buoy. In case of sinking accidents, it is difficult immediately to install the Emergency Wreck Marking Buoy because of weather conditions, marine environments and accident position. This paper studies Auto Releasing New Danger Mark Buoy on the deck which can be automatically to release from the deck of a vessel and float in the water and quickly install the accident position in case of sinking accidents. The buoy will be to reduce the risk of navigation and prevent secondary collisions.

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.1
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• pp.35-44
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• 2005

Microclimate of Gwangneung forest watershed is characterized by analyzing wind, radiation, profiles of air temperature and humidity, soil and bole temperature, precipitation and soil water content measured at and around the flux tower from April 2000 to September 2003. Mountain-valley wind was prevalent due to the topographic effect with dominant wind from east during daytime and relatively weak wind from west during nighttime. Air temperature reaches its peak in July-August whereas monthly-averaged incoming shortwave radiation shows its peak in May due to summer monsoon. Albedo ranges from 0.12 to 0.16 during the growing season. Monthly-averaged bole temperature is in phase with monthly- averaged air temperature which is consistently higher. Monthly-averaged soil temperature lags behind air temperature and becomes higher with leaf fall. With the emergence of leafage in April, maximum temperature level during midday shifts from the ground surface to the crown level of 15-20m in May. Profiles of water vapor pressure show a similar shift in May but the ground surface remains as the major source of water. Vapor pressure deficit is highest in spring and lowest in winter. Monthly averaged surface soil temperatures range from 0 to 20℃ with a maximum in August. Monthly averaged trunk temperatures of the dominant tree species range from -5.8 to 21.6℃ with their seasonal variation and the magnitudes similar to those of air temperature. Annual precipitation amount varies significantly from year to year, of which >60% is from July and August. Vertical profiles of soil moisture show different characteristics that may suggest an important role of lateral movement of soil water associated with rainfall events.

• Journal of the Korean Arthroscopy Society
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• v.3 no.2
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• pp.132-137
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• 1999

Displaced tibial spine fractures need the anatomical reduction of the displaced bone fragment to achieve normal range of motion and anterior stability of the knee joint. The purpose of this paper is to describe details of arthroscopic technique using suture hook and pull-out PDS and to evaluate the clinical results. We report 7 cases who underwent arthroscopic reduction and internal fixation using suture hook and pull-out PDS. All cases had fresh fractures generated within 3 weeks. The follow up period was at average 16.6 months. The fracture union was achieved at average 7.4 weeks. Knee exercise was started 2 weeks after the operation. One of the patients, who had combined injury of posterior cruciate ligament and lateral meniscus, showed limitation of knee movement. But he was underwent the arthroscopic fibrolysis at one year later, he returned to normal range of motion. Arthroscopic treatment of displaced tibial spine fracture using suture hook and pull-out PDS showed good results including rigid fixation and early mobilization. Therefore it is thought to be one of the effective operative techniques in treatment of the tibial spine fractures.

• Journal of Oral Medicine and Pain
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• v.37 no.4
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• pp.205-211
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• 2012

A 35 year-old female presented with the complaint of sudden occurrence of bite change and concurrent opening limitation, as well as pain in the right temporomandibular joint (TMJ) during mouth opening. From her history it was revealed that she had simple clicking of right TMJ for several years before onset of these symptoms, and that the clicking sound subsided recently after development of opening limitation. On clinical examination, anterior open bite, midline shift of the mandible to right, and premature contacts on left posterior teeth were observed. Maximum mouth opening and lateral movement to left were also restricted. On magnetic resonance images, the right TMJ showed anterior disc displacement without reduction and the posterior joint space is greatly collapsed by retrusion of the condyle. It was thought that the sudden occurrence of occlusal change would be resulted from abrupt displacement of the mandible associated with development of the anterior disc displacement without reduction. The stabilization appliance traction therapy was performed initially for first 3 months along with physical and pharmacologic therapy. However, the anterior open bite and opening limitation didn't resolve and the position of mandible still remained altered. So the stabilization appliance was changed to intermaxillary traction device. Then the mandible returned progressively to normal position and the occlusion became more stable and comfortable. After 5 months of intermaxillary traction therapy, the anterior open bite was dissolved completely and the occlusion became stabilized satisfactorily along with recovery of normal mouth opening range. On post-treatment magnetic resonance image, remodeling of condylar head was observed.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.1
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• pp.26-32
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• 2005

A tooth impaction means a state that a tooth does not erupt out of oral mucosa or alveolar bone for many reasons. The reasons for an impaction of the Maxillary central incisor are an odontoma, supernumerary tooth, space loss, prolonged remaining or early loss of a preceding deciduous tooth, abnormalities of crown or root caused by trauma of a deciduous tooth and an ectopic position of a tooth germ. In the case of the impacted maxillary incisor, a rapid mesial movement of a lateral incisor leads a space loss and a midline deviation can be happened. Furthermore, it can cause a cyst. When we treated a patient with an impacted central incisor early, we could see a better prognosis. It means an early diagnosis and an exact treatment are very important. Generally if the impaction is not severe or it is caused by a keratinized covering tissue, a surgical exposure can induce an eruption easily but an orthodontic force is recommended when an eruption does not happen after a surgical method, when the eruption path is too transpositioned to be corrected spontaneously and when an impacted tooth is located so deeply. In the treatment using an orthodontic force, careful considerations about a root length, pulp, and a periodontal tissue can improve the periodontal and esthetic prognosis for the long follow-up results. This case is using an orthodontic traction following a periodic observation and in no expectation of spontaneous eruption. After treatment of this case, I have got some knowledges, so I report this case.

• The korean journal of orthodontics
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• v.28 no.3 s.68
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• pp.431-440
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• 1998

While periodontal disease results in the extrusion of upper incisors with interdental spacing in adult patient, the intrusive movement should be executed for the rehabilitation in terms of esthetics and function. The present study was peformed to investigate the periodontal response following orthodontic intrusion of teeth with infrabony pocket. Bone defect and periodontal disease were produced adjacent to the both maxillary second lateral incisors in four adult dogs. Four weeks later, a flap operation was performed to eliminate inflammation and a reference notch was made on the root surface at the level of bottom of each defect. Two weeks after periodontal surgery, 4 weeks of intrusion and subsequent another 4 weeks of retention was executed on the right side of incisors while left incisors served as the control. Through the histologic analysis, following results were obtained. 1. Histologic section of control side showed the reduction of pocket depth after flap operation. However, the status of long junctional epithelium was observed while new connective tissue attachment occurred in a small area adjacent newly formed cementum 2. Epithelial attachment was less around the intruded incisor while new connective tissue attachment was much more compared to the control side. 3. Plenty of cells were observed in the connective tissue around the reference notch of the intruded incisor and the degree of the new cementum formation was higher in the intruded incisor than the control. The results of the present study suggested that an orthodontic intrusion of periodontally involved and extruded incisors could be carried out with a desirable periodontal response, provided that inflammation is under control.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.4
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• pp.320-324
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• 2010

Introduction: The placement of a single miniplate is not sufficient to achieve rigid fixation in mandibular angle fractures. It often causes difficulties in reducing the intermaxillary fixation (IMF) period. Consequently, the placement of 2 miniplates is preferable. The intraoral approach in an open reduction and internal fixation (ORIF) of a mandibular angle fracture with 2 miniplates is often challenging. Accordingly, an alternative of transbuccal approach is performed. However, this method leaves a scar on the face and can result in facial nerve injury. This clinical study suggests a protocol that can maintain rigid fixation without a transbuccal approach in mandibular angle fractures. Materials and Methods: The subjects were 7 patients who sustained fractures of the mandibular angle and treated at Department of Oral and maxillofacial surgery, Sacred Heart Hospital, Hallym University. ORIF under general anesthesia was done using the intraoral approach. One miniplate was inserted on external oblique ridge of the mandible, and the other was placed on lateral surface of the mandibular body with contra-angle drill and driver. A radiographic assessment and occlusal contact point examination was carried out before surgery, and 2, 4 and 6 weeks after surgery. Results: The mean operation time was 80 minutes. Regarding the occlusion state, the number of contact points increased after surgery. Paresthesia and infection were reported to be complications before surgery. Conclusion: The placement of 2 miniplates using contra-angle drill for ORIF of mandibular angle fractures allows early movement of the mandible without IMF. We propose this approach to reduce the patients’discomfort and simplify the surgical procedure.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.3
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• pp.453-458
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• 2004

Mandibular fracture is less common in children than in adults. However, children are more susceptible to ankylosis and developmental disorders, and don't respond as well to intermaxillary fixation compared to adults. On the other hand, bone fracture is healed more quickly in children and complications are scarce. Mandibular fracture in children is usually treated successfully with acrylic splint therapy with or without the use of eyelet wires and intermaxillary fixation. Severe complications that include ankylosis and developmental disorders may occur. The frequency and severity of such complications can be mitigated with a shorter duration of intermaxillary fixation and good post-operative care. Encouraging mandibular physical therapy by increasing patient motivation may be necessary in such cases where the patient's response is poor and the duration of intermaxillary fixation increases; when the patient is unable to undergo physical therapy, or when intermaxillary fixation is not necessary with the patient showing only minor symptoms such as trismus. In this case report, a 6 year-old girl with bilateral condylar fracture was treated with elastic in both the upper and lower jaws to allow mandibular physical therapy using a Benoist's appliance, which allows opening, lateral, and protrusive retrusive movements of the mandible. A 7-month follow-up showed beneficial therapeutic effects such as increased mandibular movement and prevention of condylar ankylosis.

• Journal of Embryo Transfer
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• v.28 no.3
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• pp.297-302
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• 2013

Cryopreservation of epididymal spermatozoa offers a potential tool for rescuing genetic material from males of genetically elite populations. Castration, catastrophic injury, sudden death or any other event that makes semen collection or mating impossible may prematurely terminate a stallion reproduction. Stallion epididymal spermatozoa vary widely in the loss of progressive motility, acrosomal integrity, and viability during freezing and thawing. The objective of this work was to investigate the effect of (1) freezing package types on cryopreservation efficiency, (2) thawing temperatures (37, 56 or $70^{\circ}C$) on Computer Assisted Sperm Analysis (CASA) parameters and (3) post-thawing incubation time (0, 1, 2 or 4h) on castrated stallion epididymis. Post-thawed sperm motility ranged between 59.69% and 64.28% ($56^{\circ}C$ and $37^{\circ}C$) in various thawing temperatures. When stallion epididymis sperm was frozen, straw was better than freezing tube on VCL (Velocity of Curvilinear Line) and VAP (Velocity of Average Path) parameter. Higher percentage of motility was observed at $37^{\circ}C$ thawing temperature even though no significant difference was observed among various temperatures. The motility, VCL, ALH (Amplitude of Lateral Head displacement), VAP, BCF (Beat-Cross Frequency) and STR (Straightness index) parameter of post-thawed sperm were significantly decreased by increasing the incubation time for all thawing temperatures. The present study showed that type of freezing package (Straw vs. Freezing tube) was not significantly different on cryopreservation efficiency. Furthermore, stallion epididymal spermatozoa frozen-thawed at $37^{\circ}C$ for 1 min resulted the highest proportion of motility and velocity movement. In addition, motility and viability of frozen-thawed stallion epididymal spermatozoa were also decreased by incubation.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.2
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• pp.285-294
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• 1991

The human temporomandibular joint as a ginglymoarthrodial one has much in common with the other synovial joints of the body, but it does possess an unique charachteristic in that it must accomodate the various occlusal relations of dentition during an end point of closure. For that reason, the movement of the condyle in the temporomandibular joint is susceptible to influences from the nature of occlusion. Undue loading to the temporomandibular joint can be applied on the occasion of premature contacts in centric relation, balancing side interferences, change of occlusal surfaces due to excessive attrition, loss of tooth. Such occlusal disharmonies in association with the systemic and emotional factors may give rise to the temporomandibular disorder. On the other hand, the changes of occlusal patterns in the growing body can also have an effect on the growth of the temporomandibular joint through the alterations of functional stresses. The purpose of this study was to observe histopathologic response of the temporomandibular joint in unilateral chewing on one side exclusively for 10 months. Three dogs showing normal masticatory function were chosen. One dog aged about 12 months was for control, two dogs for experimental specimens were about 12 and 18 months old respectively. For chewing on the left side only, unilateral lower right premolar and molar were extracted in two experimental specimens. And then three dogs were sacrificed 10 months later. Frontal histologic sectioning of joints were done for the observation of the effects of one-side chewing. 24 specimens from three dogs were obtained and fixed in 10% formalin and routinly processed with H-E staining for histologic examination. The light microscopic findings were interpretated as follows: 1. Experimental specimen 1 aged about 22 months: In comparison with control and right non-chewing side, the proliferative and hypertrophic zone were increased at the mesial and lateral part of left chewing side condyle. There was no change of the articular tissue of temporal bone. 2. Experimental specimen 2 aged about 28 months: The articular tissues of adult joint were observed. The differences between the chewing and non-chewing side were not seen in the articular tissues of condyle and temporal bone.