• Journal of the Korean Society of Groundwater Environment
• /
• v.1 no.2
• /
• pp.100-104
• /
• 1994

The rock matrix diffusion provides a retarding mechanism for sorbing and especially non-sorbing radionuclides. It has to be verified not only theoretically and experimentally but also from natural phenomena, before the mechanism can be incorporated fully into transport codes. The natural analogue studies, such as the concentration variation of radionuclides in profiles perpendicular to fluid-conducting fractures and to intrusive contact zones, have been believed to provide a validation. In thermal alteration zones of Naeduckri granite intruded by a pegmatite, large alkali and alkaline earth elements such as K, Rb, Sr, and Ba were moderately migrated during thermal alteration. Li, V. and Nb were also migrated about 9cm in width from the contact between the granite and the pegmatite. The concentration variation of these elements in thermally altered zones seems to be resulted from the local migration due to the re-equilibration among the elements released from the breakdown of primary minerals in the granite. Most of these natural analogue studies simply show only the concentration variation of elements without detailed informations on the diffusion time and other important data fir interpreting the behaviour of radionuclides, because of the absence of appropriate minerals for age data. Despite this problem, natural analogue studies will be needed for transport models of radionuclides in safety assessment.

• Radiation Oncology Journal
• /
• v.24 no.2
• /
• pp.88-95
• /
• 2006

Purpose: We evaluated whether Cyberknife radiosurgery is an effective and safe method of therapy for medically intractable trigeminal neuralgia (TN). Materials and Methods: We retrospectively analyzed the outcome of 26 patients, who failed to surgery or were not suitable candidates for invasive intervention and were treated by Cyberknife radiosurgery between March 2004 and May 2005. Radiosurgery doses of $60{\sim}64 Gy$ were delivered to the 80% isodose line prescribed to an 6 mm length of the nerve, sparing the most proximal 3 mm away from the trigeminal nerve root entry zone (median dose: 64 Gy). Results: Follow-up period was $3{\sim}15$ months (median follow-up period: 9 months) Preliminary results from a cohort of 26 patients undergoing Cyberknife radiosurgery for TN showed that pain relief was achieved in 50% (13/26) of patients within the first 24 hrs after treatment. At last follow-up, 96.2% (25/26) of patients reported early pain relief within 7 days. Treatment failure developed in 2 of 26. Poor response occurred in one patient and relapse was observed in the other patient. 3 patients had hypoesthesia (11.5%), which was the only complication observed with any of our patients. Conclusion: With these results, authors assumed that Cyberknife radiosurgery for TN could be one of safe and effective therapeutic methods.

• Restorative Dentistry and Endodontics
• /
• v.21 no.1
• /
• pp.107-120
• /
• 1996

복합레진은 조작이 용이하고 강도가 우수하며 중합시간이 짧고 법랑질과 상아질에 접착이 가능하며 연마성이 뛰어나고 자연스러운 색상을 나타내므로 심미적 수복에 가장 일반적으로 선택되는 재료의 하나이다. 대부분의 복합레진 kit에는 shade guide가 포함되어 있어 이를 기준으로 중합된 후의 복합레진 색조를 예상하여 선택하게 된다. 그러나 이러한 shade guide들은 대개 복합레진이 아닌 plastic으로 제조된 것으로 중합된 복합레진의 실제 색조와는 차이가 생기게 되며 결국 shade guide 자체의 문제점으로 인해 이상적인 색조선택이 어려워진다. 이에 본 연구에서는 국내에 시판되고 있는 5종의 복합레진 제품을 선정하여 분광 광도계를 이용해서 shade guide와 중합된 복합레진 사이의 색조차이를 측정, 비교 연구하였다. 직경 16mm. 두께 1.6mm의 plastic mold에 5종의 광중합형 복합레진(Z100, Prisma TPH, Tetric, Silux Plus, Herculite XR)을 충전하고 응축기에 넣어 압축한 후 제조사의 지시에 따라 광중합기로 중합시킨 후 mold에서 시편을 제거하여 보관했다가 젖은 sandpaper 상에서 순차적으로 연마하였다. shade guide는 step부분을 갈아내어 복합레진 시편과 동일한 두께로 만든후 연마하였다. 분광광도계에 shade guide를 넣고 CIE illuminant D65 하에서 spectral reflectance를 측정하고 해당 색조의 복합레진 시편도 통일한 방법으로 측정하고 $L^*$, $a^*$, $b^*$값과 ${\Delta}E^*$값을 얻은후 분석하여 다음과 같은 결과를 얻었다. 1. Z100의 D3, A3, B2 shade와 Prisma TPH의 B2 shade를 제외한 모든 시편에서 shade guide와 복합레진간에 육안으로 인지할 수 있는 색차(${\Delta}E^*$ > 1.0)가 관찰되었다. 2. 평균적으로 Z100이 가장 적은 색차를 나타내었고 Prisma TPH, Tetric, Silux Plus, Herculite XR 순으로 색차가 증가하였다. 3. Prisma TPH의 A2 shade. Tetric의 W shade. Silux Plus의 YB, U shade, Herculite XR의 L, LY shade는 ${\Delta}E^*$값이 3.3 이상으로 나타났다. 4. Z100, Prisma TPH, Tetric, Silux Plus에서는 복합레진보다 shade guide가 더 높은 $L^*$값을 보이는 경향이 나타났으며, Herculite XR에서만 복합레진이 더 높은 $L^*$값을 나타냈다. 5. 모든 시편에서 $b^*$ 값은 (+)로 관찰되었고, Z100, Prisma TPH, Tetric, Silux Plus의 shade guide는 복합레진에 비해 높은 $b^*$값을 보였다. 6. 모든 시편에서 $a^*$값은 (-)로 관찰되었고. Herculite XR 및 Silux Plus에서는 복합레진이 shade guide 에 비 해 낮은 $a^*$값을 나타냈다.

• 한국HCI학회:학술대회논문집
• /
• 2009.02a
• /
• pp.961-970
• /
• 2009

Over the last decade, interactive devices such as mobile phones have become complicated drastically mainly because of feature creep, the tendency for the number of features in a product to rise with each release of the product. One of the ways to reduce the complexity of a multi-functional device is to design it consistently. Although the definition of consistency is elusive and it is sometimes beneficial to be inconsistent, in general, consistently designed systems are easier to learn, easier to remember, and causing less errors. In practice, however, it is often not easy to design the user interaction or interface of a multi-functional device consistently. Since the interaction design of a multi-functional device should deal with a large number of design variables and relations among them, solving this problem might be very time-consuming and error-prone. Therefore, there is a strong need for a well-developed methodology that supports the complex design process. This study has developed an effective and efficient methodology, called CUID (Consistent Design of User Interaction), which focuses on logical consistency rather than physical or visual consistency. CUID deals with three main problems in interaction design: procedure design for each task, decisions of available operations(or functions) for each system state, and the mapping of available operations(functions) and interface controls. It includes a process for interaction design and a software tool for supporting the process. This paper also demonstrates how CUID supports the consistent design of user interaction by presenting a case study. It shows that the logical inconsistencies of a multi-functional device can be resolved by using the CUID methodology.

• Proceedings of the Korea Society of Information Technology Applications Conference
• /
• 2007.05a
• /
• pp.281-299
• /
• 2007

IS/IT 분야 실무자가 지니고 있어야 한다고 생각되는 지식과 전문 기술들을 '지식/능력 영역'과 '소프트웨어 전문 기술 영역'으로 구분하여 각각 세부 항목을 명세하였다. 그리고 분류된 두 영역에 대하여 IS/IT 분야 실무자가 생각하는 필요한 지식 및 전문 기술들의 중요도와 IS/IT 전공 교수가 생각하는 IS/IT 실무자에게 필요한 지식 및 전문 기술들의 중요도를 조사하여 두 그룹간의 인식차 비교를 시도하였다. 조사지역은 실무자는 충청지역 및 수도권 지역에 분포하는 SI 업체를 대상으로 이루어 졌다. IS/IT 실무자를 대상으로 한 조사는 실무자 본인의 일장에서 IS/IT 실무자가 갖추어야 된다고 판단되는 지식 및 전문 기술들의 중요도를 측정하였다. 그와 더불어 그들이 수행하는 IS 활동에 대하여 투자한 시간을 기준으로 군집분석을 실시하여 세가지 그룹으로 구분하여 실무자 전체와 세 그룹간의 비교가 가능하도록 조차되었다. 비교 결과, 지식/능력 영역에서는 IS 실무자들이 상대적으로 '하드웨어에 대한 지식', '특정 조직', '운영체제에 대한 지식'에 대해 더 높은 중요도를 부여하고 있는 것으로 나타났다. 소프트웨어 전문 기술 영역에서는 실무자보다 전공교수가 생각하는 중요도가 보편적으로 더 높게 나타났다. 전공 교수는 '프리젠테이션 도구', '객체지향 언어(C++, Java 등)'에 4점 대의 높은 점수를 주어 중요한 것이 무엇인가 하는 인지가 있는 것으로 보이나 실무자 그룹에서는 특별히 중요시 여기는 항목이 명확히 드러나지 않고 보편적인 값이 median 값 주변에 위치하고 있다. 이는 현재 실무자들이 빠르게 변화하고 있는 IS/IT 환경에서 본인의 경력경로 (career path)을 위해 무엇이 중요한 갓인지 아직 명확히 하고 있지 못하는 것으로도 해석이 가능하다. 자세한 비교/분석 및 해석은 현재 진행 중이며, 여러 흥미로운 해석이 가능할 것으로 기대 된다.합형 파괴가 증가하는 경향을 나타내었다. 이상의 결과로, 상아질 접착제의 접착단계/과정이 결합내구성에 영향을 미침을 알 수 있었다. 따라서 접착과정의 단순화가 반드시 접착에 효과적이라고 할 수 없다.는 저작 운동 잔에는 2군에서 Heliomolar가 Pyramid보다 변연적합도가 우수하였고 (p < 0.05) 그 외의 군에서는 유의차가 없었으며, 저작 운동 후에는 모든 군에서 재료간 유의차가 없었다. 각 부위별 변연적합도를 비교하면, 저작 운동 전 Pyramid에서는 교합면 변연에서는 4군이 2군에 비해 높은 변연적합도를 보였고 (p < 0.05), 인접면과 치은면에서는 군 간 유의차를 보이지 않았다. Heliomolar에서는 교합면 변연에서 2, 4군이 1군에 비해 높은 변연적합도를 보였고 (p < 0.05), 인접면과 치은면에서는 군간 유의차를 보이지 않았다. 저작 운동 후 Pyramid에서는 교합면 변연에서는 3군이 1, 2군에 비해 높은 변연적합도를 보였고 (p < 0.05), 인접면과 치은면에서는 군간 유의차를 보이지 않았다. Heliomolar에서는 교합면에서 2, 3, 4군이 1군에 비해 변연적합도가 높았으며 (p < 0.05), 인접면과 치은면에서는 군간 유의차를 보이지 않았다 이번 연구를 통하여 복합레진을 간헐적 광중합시킴으로써 변연적합도가 향상될 수 있음을 알 수 있었다.시장에 비해 주가가 비교적 안정적인 수준을 유지해 왔다고 볼 수 있다.36.4%)와 외식을 선호(29.1%)${\lrcorner}$ 하기 때문에 패스트푸드를 이용하게 된 것으로 응답 하였으며, 남 여 대학생간에는 유의한 차이(p<0.05)가 인정되었다. 응답자의 체형은 ${\ulcorner}$적당하다${\lrcorner}$고 응답한 경우가 가장 많이 이러한 음식을 즐겨 먹었으며(49.5%), 그 다음은 뚱뚱한 경우도 비교적 많이 먹고

• Journal of the Korean earth science society
• /
• v.21 no.3
• /
• pp.302-314
• /
• 2000

Keumseong area in the southern part of the Jecheon city, the Ogcheon Belt, consists of Precambrian Dangdusan Metamorphic Complex, Dori Formation of the Choseon Supergroup, and Jurassic Jecheon Granite. The Dangdusan Metamorphic Complex consists of quartz schist, mica schist. quartzite and pegmatite. The Dori Formation is composed of mainly laminated limestone. The rocks in the study area have been undergone at least three phases of deformations since Paleozoic period. The Dangdusan Metamorphic Complex is outcrop at three areas in the study area, which are exposed along the faults and occurred as inlier within the Dori Formation. Previous authors interpreted the uplift of the Dangdusan Metamorphic Complex by the Dangdusan Fault, but we could not find any evidences related to the Dangdusan Fault. Thus, we interpret the uplift of the Dangdusan Metamorphic Complex due to the D$_2$ Weolgulri and Dangdusan thrusts and post-D$_2$ Jungbodeul, Kokyo and Jungjeonri faults. The uplift of the Busan Metamorphic Complex to the west of the study area was interpreted by ductile deformation. However, the Dangdusan Metamorphic Complex is formed by brittle thrusts and faults in this study. According to deformation sequence, the characters of deformations in the Choseon and Ogcheon suprergroups had been changed from ductile to brittle deformations through the time. Therefore, we interpret the Dangdusan Metamorphic Complex is exposed later than the Busan Metamorphic Complex.

• Investigative Magnetic Resonance Imaging
• /
• v.1 no.1
• /
• pp.154-161
• /
• 1997

Purpose: Traumatic rupture of the diaphragm is not easy to diagnose and often delayed. Delayed diagnosis of diaphragmatic rupture accompanied by higher chances of strangulation of herniated viscera which may result in higher morbility and mortality. The purpose of this study was to evaluate diagnostic accuracy of spiral CT, MRI and US for the diagnosis of diaphragmatic rupture in an animal model. Materials and Methods: Small, medium, and large sized transabdominal diaphragmatic ruptures were surgically made in experimental rabbits and then followed up with spiral CT, MR!, and US at 1 day, 3 day, and 1 week after operation. Results: US was superior to MR! or spiral CT in diagnosis of diaphragmatic rupture(P(0.05). The sensitivity and specificity were 94.4% and 92.9% for US, 54.0% and 85.7% for MRI, and 46.0% and 78.6% for spiral CT, respectively. The size of laceration was not related to diagnostic sensitivity in US. Sensitivity of MRI and spiral CT increased as the size of laceration were larger, but no statistical significance was present(P>0.05). All experimental animals developed pleural effusion or hemothorax one day after operation. In acute phase, US and MRI were more sensitive than spiral CT in detecting diaphragmatic rupture. Spiral CT was more sensitive than US and MRI in delayed phase but without statistical significance(P>0.05). In the experimental rabbits with accompanying visceral hernia through the diaphragmatic defect, diagnostic accuracy was found equally high among three image modalities(P>0.05). Conclusion: This study indicates that US is the most accurate diagnostic method in detecting injury to the diaphragm in a rabbit model. The findings obtained in this experimental study can be applied to the diaphragmatic rupture of human being.

• Journal of Soil and Groundwater Environment
• /
• v.10 no.1
• /
• pp.65-74
• /
• 2005

National groundwater monitoring stations have been managed throughout the country by Korea Water Resources Corporation (KOWACO) in order to monitor variations in quantity and quality of groundwater resources. A multi-sensor installed in each monitoring station well measures groundwater level, water temperature and electrical conductivity every six hours and the logged data are automatically transmitted to a host computer in KOWACO. Meanwhile despite regular station inspection and replacement of deteriorate or broken devices, abnormal values or outliers often occur due to intrinsic limitations of automatic monitoring and transmission. Thus prompt recognition and measures to these values are essentially required to reduce disturbance and missing period of the data. In this study, time and frequency of outlier occurrence were analyzed for the water level data obtained from national groundwater monitoring stations within the Han river basin in 2000. The analysis results indicated that the most prominent patterns of the outliers were rapid decline for water level, no variation for temperature and steep decline for electrical conductivity. This study provided a sample criterion for determining the outlier for each parameter.

• Journal of Korean Society of Transportation
• /
• v.30 no.4
• /
• pp.43-59
• /
• 2012

Assuming a completed Smart Highway road & communication environment that allows real-time information collection and transmission of road traffic condition ahead, the purpose of this study is to develop a plan for inducing a network-level safe driving pattern by providing road traffic condition and safety information to multiple drivers through a road information provision device. In this study, the device with a function that displays different colors according to the hazard level to the existing delineator has been named 'Smart Delineator'. Smart Delineator is a device that provides not only alignment information but also safety information for drivers to receive real-time warning information and intuitively recognize road traffic condition ahead so that drivers can respond. To examine the effects of safety driving inducement level on drivers, a simulation test was conducted using driving simulator as well as a satisfaction survey. The result showed that the Smart Delineator was able to identify the location of occurrence and affecting driving according pattern, either adhering to recommended speed or reducing speed according to the pre-defined hazard level.

• Journal of Science Education
• /
• v.38 no.1
• /
• pp.133-143
• /
• 2014

The purpose of this study is to analyze elementary school teachers' perception on application of STEAM education. For this study, a survey was administered to 80 primary teachers. The result showed as follows: First, even though, elementary school teachers have known about the meaning and aims of the STEAM education in detail, they often took a neutral attitude toward the actual teaching method. In addition, they take a negative attitude toward having the gathering. Second, only a few elementary school teachers prepared and used the teaching materials related to the STEAM education in class and teach students the concept based on the STEAM education. Only a few elementary school teachers said that they used the developed modules. However, the demand, developing the modules, was extremely high. This result means that the easy and available modules should be developed to establish the STEAM education. Third, only a few elementary school teachers applied the subject, activity, and estimation related to the STEAM education in actual class. Forth, even though, after applying, there much be the positive affects, most elementary school teachers could not recognize the positive affects. At the same time, elementary school teachers suggested the curriculum should be reorganized for students to connect between the results of the STEAM education and the contents of the textbook, and the easy and available program should be developed and spread, also. The attitude of elementary school teachers toward the application of the STEAM education was normally negative. Therefore, it is needed to include more STEAM related contents in the science textbooks and to develop various STEAM education materials and circulate them as well as to establish adequate teaching and assessment methods for STEAM education.