• Journal of the Korean Society for Nondestructive Testing
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• v.20 no.5
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• pp.412-423
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• 2000

By using the relation between stress intensity factor and AE parameter, new approach method for assessing the crack length and detectability of crack was proposed. Laboratory experiment was carried out to identify AE characteristics of fatigue cracks for compact tension specimen. The relationship between a stress intensity factor and AE signals activity as well as conventional AE parameter analysis was discussed. As a result, the features of specific parameter such as the length of crack growth the AE energy, the AE peak amplitude, and the cumulative AE hits, showed the almost same trend in their increase as the number of fatigue cycle increased. From the comparisons of peak amplitude and AE energy with stress intensity factor, it was verified that the higher stress intensity factors generated AE signals with higher peak amplitude and a larger number of AE counts. If we can get more reliable database for the relation between AE parameters and stress intensity factor, this approach will provide a good information for evaluating both the existence of crack and the minimum detectable size of crack.

• Korean Journal of Veterinary Research
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• v.34 no.1
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• pp.165-172
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• 1994

DA-125 is a new anthracycline antitumor antibiotic, which is derived from adriamycin. The potential of DA-125 to induce embryotoxicity was evaluated in the Sprague-Dawley rats. One hundred twenty naturally mated SD rats(sperm in vaginal lavage=day 0) were distributed among three treated groups and a control group. DA-125 was administered intravenously at dose levels of 0. 0.1, 0.3 and 1.0mg/ kg/day. Dams were treated from day 7 to 17 of gestation and were subjected to the caesarean section on day 20. At 1 mg/kg, reduced food intake, reduced body weight and decreased weight of spleen were observed in dams. An increase in the resorption rate and a reduction in the fetal weight were also found. In addition, various types of external, visceral and skeletal malformations occurred at an incidence of 11.9, 41.8 and 14.5%, respectively. Characteristic malformations include exencephalia, gastroschisis, cleft lip, dilatation of lateral and 3rd ventricle, fused ribs, among others. There were no signs of maternal toxicity or embryotoxicity at 0.1 and 0.3mg/kg. The results show that the test agent DA-125 is embryotoxic at maternally subtoxic dose in rats.

• Applied Microscopy
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• v.42 no.1
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• pp.43-48
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• 2012

This study shows that ceresin wax, candellila wax and microcrystalline wax mixed together with liquid paraffin oil to produce lipsticks (LS-1, LS-2) and capric/caprylic triglyceride oil added to produce lipsticks (LS-3, LS-4). After each type of lipsticks were molded, LS-1 and LS-3 was put into a cooling chamber ($5^{\circ}C$). LS-2 and LS-4 was put into a cooling chamber ($5^{\circ}C$) for 18 hours and kept in an incubator ($45^{\circ}C$) for 5 hours and put again into a cool chamber ($5^{\circ}C$). After that, the wax's three dimensional network structure was observed under scanning electron microscopy. Regardless of the kind of oil, the LS-1 and LS-3 wax structure had more distinct shape than the lipstick wax structure of LS-2 and LS-4. Also, regardless of the kind of wax, the three dimensional network structure was modified as the storage temperature increased. As a result, the lipstick's molding temperature increased, the wax's structure size also increased and the shape irregularly modified. This modification causes sweating phenomenon which affected lipstick's surface rheological property.

• The korean journal of orthodontics
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• v.34 no.2 s.103
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• pp.109-119
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• 2004

This study aimed at investigating the skeletal, dentoalveolar, and soft tissue changes of Class III malocclusion cases treated by second molar extraction. The lateral cephalograms of 15 subjects with moderate Class III malocclusion by average ANB $-1.4^{\circ}\;and\;IMPA\;85^{\circ}$ were traced and the computerized superimposition of average craniofacial change was made. The data was gathered and statistically analyzed. The results were as follows: 1 Lower anterior facial height/anterior facial height increased by 0.6%(P<0.01), mandibular plane increased by $1.5^{\circ}$(P<0.05). 2. There was a slightly downward & backward rotation of the mandible. 3. Lower first molar tipped distally by 4.nm(P<0.001), lower anterior teeth lingually tipped by $3.2^{\circ}$(P<0.05). 4. Retracted lower lip improved facial profile. This study may suggest that second molar extraction could be effective for a moderate Class III malocclusion to make distalization of the lower first molar easier and avoid severe lingual tipping of the lower incisor, if the lower third molar has a normal shape, good direction of eruption and adequate time for lower second molar extraction

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.4
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• pp.500-507
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• 1998

Using a sledge net, the benthic amphipods were taken over one cycle of the neap and spring tides in January 1993 at the sandy shore surf zone of Dolsando, southern Korea. From these samples, we investigated the diel and tidal effects on the intraspecific zonation of Pontogeneia rostrata. The density of p. rostrata was higher during neap tide than spring. Of three categories (adult males and females and juveniles), juveniles and males attained to its highest density during neap and spring tides, respectively. Length- frequency data show that the high mortality of juveniles seemed to occur in winter. In the surface at night, it is significant that juveniles were significantly more abundant during neap tide than spring, whereas both adult males and females were more abundant during spring tide than neap. This suggests that the vortical migration patterns of juveniles and adults vary with the type of tides. During flood of spring tide, more than $90\%$ of population collected at the area above the mean sea level (MSL) were adults. With a decrease of female/male ratio, size of males increased there but that of female did not change, indicating an active migration of large males. This behavior can provide an extension of distribution area far large males, and also give a competitive advantage to large male against small one for mate and feeding. Although adult p. rostrata was collected at 100 cm above MSL at night during spring tide, a major portion of population as usually present on the shore below MSL. The center of zonation was restricted from 50 cm to 250 cm below MSL.

• The Journal of Korean Medicine
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• v.40 no.3
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• pp.198-223
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• 2019

Objectives: The purpose of this study was to investigate the effect of Korean medicine treatment on facial asymmetric treatment in 5 cases of facial asymmetry correction by non - surgical treatment such as acupucture, chuna treatment, FCST (Functional cerebrospinal technique) and cranial osteopathy. Methods: We analyzed the initial charts of 5 patients who had undergone facial asymmetry in a Korean medicine clinic and measured the position and distance using the photograph, lateral cephalograms, and whole body radiograms. The results were as follows. Results: To quantify both soft and hard tissues to confirm the results of Korean medicine treatment of facial asymmetry, soft tissues quantitatively measure the displacement of the face, the slope of the left and right eyes, and the slope of the lip in order to grasp the positional displacement of the mandible. As a result, on the average, the correction effect as measured by the angle difference between A and C is $1.8{\pm}0.57$, the correction effect as measured by the angle difference between B and C is $1.4{\pm}0.89$, and the angle difference between D and the horizontal plane is $1.9{\pm}0.89$, and the angle difference between E and the horizontal plane is $1.9{\pm}0.89$. The result of reduced angle difference between A and C means that the head position shifted from the center of the body to the unilateral side was shifted to the center. The decrease in the angle difference between B and C means the restoration of the maxillary distortion relative to the mandible. In hard tissues, numerical values were measured based on the skull standard. The average distortion of the skull was $1.9{\pm}0.67$, and the distortion of the lower eye was $1.4{\pm}0.41$. Conclusion: General studies on facial asymmetric treatment are limited to treatments such as surgery and orthodontics. However, this study confirmed the possibility that facial asymmetry could be corrected by Korean medical treatment consisting of reversible non-surgical treatment rather than irreversible treatment such as surgery or orthodontic treatment. In particular, Korean medicine treatment is effective for muscular asymmetry, soft asymmetry, functional asymmetry, etc. The facial asymmetric treatment of Korean medicine is not limited to the face-centered correction, but the asymmetry of the whole body may be corrected as well.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.14 no.2
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• pp.97-101
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• 2018

Lesch-Nyhan syndrome is a rare X-linked recessive genetic disorder. During purine metabolism, the hypoxanthine guanine phosphribosyl transferase (HGPRT) enzyme is deficient causing phosphoribosyl transferase to accumulate and resulting in excessive uric acid. Clinical symptoms include hypercalcemia, choreoathetosis, spasticity, mental retardation, and self-injury to lips, tongue or fingers. This results not only in pain caused by the self-injury but also secondary infection of the wound site and the esthetic damage of the soft tissue defect. Dental treatments include conservative methods using intraoral appliances such as soft mouthguards, fixed lip bumpers, and occlusal guards, and invasive methods such as extraction of all teeth or forming an artificial anterior open bite. We report two cases of Lesch-Nyhan syndrome patients with self-mutilation behavior; one was treated with a preservative method using a soft mouthguard, and the other was treated with extraction of all teeth.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.2
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• pp.175-186
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• 2022

A crossed occlusion resulting from the presence of posterior teeth in one arch but no opposing teeth in the opposite arch results in collapse of the vertical dimension. In this case, the patient has a class III malocclusion with crossed occlusion and anterior crossbite. In order to evaluate the proper vertical dimension, provisional denture was used to stabilize the vertical occlusal dimension for 3 months. After, provisional fixed restoration was used for the stabilizing occlusal relationship and aesthetic improvement for lip support. Definitive prosthesis in implants in the mandible and abutments in the maxillary were using Porcelain-fused-to-metal crown (PFM) crown and the maxillary unilateral edentulous area was treated with removable partial dentures. Through this, proper support of the posterior region and normal anterior occlusal relationship were formed, and the patient was able to obtain aesthetically and functionally satisfactory treatment results.

• Journal of the Korea Society for Simulation
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• v.31 no.1
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• pp.29-41
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• 2022

As one of the alternatives to solve the problem of unstable food supply and demand imbalance caused by abnormal climate change, the need for plant factories is increasing. Airflow in plant factory is recognized as one of important factor of plant which influence transpiration and heat transfer. On the other hand, Digital Twin (DT) is getting attention as a means of providing various services that are impossible only with the real system by replicating the real system in the virtual world. This study aimed to develop a digital twin model for airflow prediction that can predict airflow in various situations by applying the concept of digital twin to a plant factory in operation. To this end, first, the mathematical formalism of the digital twin model for airflow analysis in plant factories is presented, and based on this, the information necessary for airflow prediction modeling of a plant factory in operation is specified. Then, the shape of the plant factory is implemented in CAD and the DT model is developed by combining the computational fluid dynamics (CFD) components for airflow behavior analysis. Finally, the DT model for high-accuracy airflow prediction is completed through the validation of the model and the machine learning-based calibration process by comparing the simulation analysis result of the DT model with the actual airflow value collected from the plant factory.

• Journal of the Korean Society for Nondestructive Testing
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• v.20 no.4
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• pp.276-284
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• 2000

The acoustic emission (AE) behavior of reinforced concrete beams tested under flexural loading was investigated to characterize and identify the source of damage. This research was aimed at identifying the characteristic AE response associated with micro-crack development, localized crack propagation, corrosion, and debonding of the reinforcing steel. Concrete beams were prepared to isolate the damage mechanisms by using plain, notched-plain, reinforced, and corroded-reinforced specimens. The beams were tested using four-point cyclic step-loading. The AE response was analyzed to obtain key parameters such as the time history of AE events, the total number and rate of AE events, and the characteristic features of the waveform. Initial analysis of the AE signal has shown that a clear difference in the AE response is observed depending on the source of the damage. The Felicity ratio exhibited a correlation with the overall damage level, while the number of AE events during unloading can be an effective criterion to estimate the level of corrosion distress in reinforced concrete structures. Consequently, AE measurement characterization appears to provide a promising approach for estimating the level of deterioration in reinforced concrete structure.