• 한국전산유체공학회지
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• 제20권3호
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• pp.62-69
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• 2015

Pressure change inside cabin as well as in tunnel has been calculated to assess the passenger pressure comfort of high-speed train. $C-STA^{TM}$, a CFD program based on axi-symmetric Navier-Stokes equation and Roe's FDS has been used to simulate the pressure change in tunnel during a high-speed train passing through it. To present the relative motion between the train and the tunnel, a modified patched grid scheme based on the structured grid system has been employed. The simulation program has been validated by comparing the simulation results with field measurements. Extensive parametric study has been conducted for various train speed, tunnel cross-sectional area and tunnel length to the pressure change in cabin. KTX-Sancheon(KTX2) high-speed train has been chosen for simulation and the train speed have been varied from 200 km/h to 375 km/h. The tunnel length has been varied from 300 m to 7.5 km and tunnel area from $50m^2$ to $120m^2$. Total 504 simulations have been conducted varying the parameters. Based on the database produced from the parametric simulations, minimum tunnel cross-sectional area has been surveyed for various train speeds based on Korean regulation on pressure change in cabin.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1454-1459
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• 2004

The major parameters governing the fluid dynamical and thermo-dynamical behavior in the large pipeline network system are friction loss and the pipeline length. But in local pipeline networks and relatively short distance pipeline system, secondary loss and the considerations of the moving states of the fluid machine are also important. One of the major element in local pressure control system is pressure regulator. It causes the variations of the physical properties in that pipeline system. When it is under working, the accurate analysis of the flow properties is so difficult. In this study, some numerical approaches to investigate the critical-flow-characteristics of the pressure regulator have been done according to the variations of the opening ratio or cross-sectional area and the detail examinations and considerations of the pressure regulator as a pipeline network elements have been carried. Finally the flow-flied distributions and critical-flow-characteristics have been presented in detail and the critical flow phenomena and the relation to the opening ratio or cross-sectional-area ratio have been studied.

• Journal of Korean Neurosurgical Society
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• 제46권3호
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• pp.199-204
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• 2009

Objective : This study was done to evaluate the correlation between carpal tunnel pressure (CTP), electrodiagnostic and ultrasonographic findings in patients with carpal tunnel syndrome (CTS). Methods : CTP was measured during endoscopic carpal tunnel release (ECTR) for CTS using Spiegelberg ICP monitoring device with parenchymal type catheter. Neurophysiologic severity and nerve cross sectional area were evaluated using nerve conductive study and ultrasonography (USG) before ECTR in all patients. Results : Tests were performed in a total of 48 wrists in 39 patients (9 cases bilateral). Maximum CTP was $56.7{\pm}19.3$ mmHg ($Mean{\pm}SD$) and $7.4{\pm}3.3$ mmHg before and after ECTR, respectively. No correlation was found between maximum CTP and either neurophysiologic severity or nerve cross sectional area, whereas we found a significant correlation between the latter two parameters. Conclusion : CTP was not correlated with neurophysiologic severity and nerve cross sectional area. Dynamic, rather than static, pressure in carpal tunnel might account for the basic pathophysiology of CTS better.

• 한국초등과학교육학회지:초등과학교육
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• 제38권1호
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• pp.116-129
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• 2019

This study investigated elementary students' spatial thinking and visualization when they learned the shape of volcanoes. For this purpose we used GeoMapApp to design instruction program and assessment items. In the instruction, students were asked to connect the floor plan view of Jeju island with the cross-sectional view of the same figure producted by GeoMapApp. Then they were asked to classify four sets of pictures of volcanoes based on the similarities of figures, that is, dome-shaped and shield volcanoes. In the assessment students solved three questions which examined how they connected the plan view and cross-sectional profile of Kilauea, draw cross-sectional profile of Mt. Fuji, and distinguished a shield volcano and dome-shaped one. Students' discourse data during the class were analyzed according to the amount to showing their spatial thinking and visualization. The instruction program using GeoMapApp assisted students to facilitate their spatial thinking for understanding of volcanoes. The outcomes of assessment showed even elementary students had good spatial thinking and visualization. Therefore, we argued spatial thinking and visualization for geoscientific understanding need to be included in the national science curriculum for elementary students.

• 건축역사연구
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• 제29권6호
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• pp.57-65
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• 2020

This study covered the Mulmae, architectural drawing recorded on Yeonggeon-uigwes and Sanleung-uigwes during the late Joseon Dynasty. In uigwes, the term 'Mulmae' was used as a mixture until the 17th century, but from the 18th century, the term 'Mulmae(勿乙每, 勿每, 水每)' was unified into 'Mulmae(水每)'. The paper of the Mulmae was made to be used during the construction period by using a thick oil paper called Yudun. Four Yudun were connected, and its size was 197.4×141cm, which was rather large. The Yingzaofashi(營造法式) of Song Dynasty describes how to draw a longitudinal section on a scale of 1/10. The scale of 1/10 was the maximum when comparing the size of the Mulmae with the buildings in uigwes. A sectional drawing of Gongpo in Geunjeongjeon was drawn on a scale of 1/10. There is a testimony that a senior carpenter drew a cross-section on a scale of 1/10. Therefore, it was determined that the scale of the longitudinal section drawn on the Mulmae paper was 1/10. The term 'the Mulmae' was used equally by carpenter active in Japanese colonial era. The scope of the painting was clarified from pillar to rafter. Uigwes records that the Mulmae was made for wood processing. Through this, it can be understood that the Mulmae painted the entire structure as a longitudinal section.

• Journal of Korean Biological Nursing Science
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• 제4권1호
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• pp.85-99
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• 2002

This study was conducted to determine whether low intensity regular exercise following steroid treatment could attenuate steroid-induced muscle atrophy. Thirty-eight Sprague-Dawley rats weighing $165{\sim}175g$ were divided into six groups ; control group(C), dexamethasone administration group(D), sedentary normal saline administration group(C+Se), exercise after normal saline administration group(C+Ex), sedentary group after dexamethasone administration(D+Se), exercise group after dexamethasone administration(D+Ex). Either dexamethasone(5mg/kg) or normal saline was injected for 7days accordingly. Exercise was started at 10m/min on the $10^{\circ}$ grade treadmill and gradually increased up to 15m/min by the 7th day for 60minutes/day($20min{\times}3$). The data were analyzed by Kruskal-Wallis test and Mann-Whitney U test using the SPSS WIN 9.0 program. Body weight, muscle weight and myofibrillar protein content of both plantaris and gastrocnemius, Type I, II muscle fiber cross-sectional area of plantaris, and Type II muscle fiber cross-sectional area of gastrocnemius in D group were significantly lower than those of C group(p<0.05) respectively. Hindlimb muscle weight, myofibrillar protein content of both plantaris and gastrocnemius. Type I muscle fiber cross-sectional area of soleus and Type I, II muscle fiber cross-sectional area of plantaris in D+Ex group tended to increase compared to those of D+Se group. Myofibrillar protein content of both plantaris and gastrocnemius, Type I muscle fiber cross-sectional area of plantaris in D+Ex group tended to increase compared to those of C+Se group. Based on these results, it is suggested that regular low-intensity exercise during recovery period after steroid treatment might facilitate the recovery from steroid-induced muscle atrophy.

• 치과방사선
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• 제29권1호
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• pp.209-221
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• 1999

Purpose: The purpose of this study was to calculate the size and CT number of both normal parotid and submandibular gland. and evaluate their relation to sex, age and obesity using computed tomography. Materials and Methods: The computed tomography was performed parallel to the Frankfurt plane in 46 subjects with healthy salivary gland. The subjects were divided into the three groups (young, middle. old) according to their ages. The size of salivary gland was determined as maximum cross-sectional area and the CT number of salivary gland was determined as the mean CT number of three ROI's. The body mass index was calculated from weight and height. Results: The mean maximum cross-sectional area was 7.79(±1.25)cm² on parotid gland and 4.12(±0.83) cm² on submandibular gland. The mean CT number was -4.43(±23.87) HU on parotid gland and 50.01(±15.63) HU on submandibular gland. There was decreasing pattern of the maximum cross-sectional area of submandibular gland and the CT number of both parotid and submandibular gland according to age(p<0.05). As the body mass index increased. the maximum cross-sectional area of parotid gland increased and CT number of both parotid and submandibular gland decreased(p<0.05). The maximum cross-sectional area of submandibular gland in male was larger than that in female(p<0.05). As the maximum cross-sectional area and CT number of left salivary gland increased. those of right gland increased(p<0.05). Conclusion : Intra-individual differences in salivary gland size and CT number is considered in the age and individual obesity.

• Journal of Oral Medicine and Pain
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• 제35권3호
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• pp.193-202
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• 2010

저자는 상기도부의 동적변화를 관찰하여 수면시의 협착부위와 그 정도를 확인하며, 하악의 전방이동이 상기도부에 미치는 영향과 부위를 조사하고자 하였으며 총 9명의 건강한 피험자를 대상으로 임상적 검사, 방사선학적 검사 및 간이수면다원검사를 실시하여 코골이 및 수면무호흡증 등의 수면장애가 없음을 확인한다. 각성시 및 수면시, 하악의 안정위 및 전방이동시에서 각각 전자선 단층촬영(EBT)을 시행하여 각 조건하의 구인두의 부위별 최대 최소 단면적 및 허탈지수를 구하였다. 이때 수면의 유도를 위해 Dormicum$^{(R)}$을 정맥투여하였다. 그 결과, 각 조건에 따라 비교하였을때 수면 및 하악 전돌에 따른 상부, 중간부, 하부 상기도간의 최소 단면적 및 허탈지수의 유의한 차이는 없었다. 반면 하악 안정위에서 각성 및 수면상태간의 비교시에 구인두의 하부에서 단면적의 유의성 있는 차이가 관찰되었다. 한편, 각성상태에서 하악 안정시와 전돌시간의 비교시에는 중간부에서 단면적의 유의성 있는 차이과 관찰되며 수면상태에서는 하악 안정시와 전돌시 단면적의 변화율을 나타내는 허탈지수에 있어 유의한 차이는 없었다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2003년도 가을 학술발표회 논문집
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• pp.123-129
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• 2003

Drift design using resizing techniques can be a very practical method in drift design of high-rise buildings since it cannot require sensitivity analysis and structural re-analysis. Resizing techniques has used the cross sectional areas as design variable and supposed that displacement participation factors are inversely proportional to structural weights. Efficiency of resizing techniques based on displacement participation factors may depend on proper selection of sectional properties as design variables. In this study, two different drift design methods with the different sectional properties as design variables are presented and applied to a 20-story structure.

• 비교문화연구
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• 제36권
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• pp.211-240
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• 2014

This is a cross-sectional study designed to analyze the correlation between the structural and social variables and the pattern of contraction and deletion of the copula verb in the speech of African American Vernacular English (AAVE) speakers in Athens in Georgia, USA using a questionnaire. The results show that the frequency of copula contraction is higher than that of deletion in all factor groups including the age of the speakers where this study found that younger speakers tend to have higher frequency of contraction and deletion of the copula than older speakers. This study analyzes this as a function of the fact that younger speakers of AAVE are conscious of the linguistic and social differences between AAVE speakers and speakers of Standard American English (SAE) and they consciously make choices regarding which norm to use at which contexts to satisfy their communicative and socio-cultural needs. This sort of conscious social behavior is not likely to disappear with age rather it might increase as a correlate of the perceived physical, socio-cultural and psychological distance between AAVE speakers and speakers of other varieties. This study shows that such perceived linguistic, socio-cultural and psychological distance has negative effects on pedagogy and I proffer the remedy.