• 한국초등과학교육학회지:초등과학교육
• /
• 제23권2호
• /
• pp.110-115
• /
• 2004

This study investigated the effects of the project approach in science teaching on scientific knowledge and attitudes, science related attitudes of the 6th grade students. Students engaged in the study were divided into comparison group and experimental group. The project approach was applied to the experimental group with various activities while the traditional teaching method was applied to the comparison group with science text book and teacher's guidebook. The data were statistically analysed by SPSS WIN 8.0. The results are as follows: The students of the project approach in science teaching made significant progress in scientific knowledge and attitudes, science related attitudes (p<.05). The students in the project approach was more effective in improvement of curiosity, critical thinking, positive thinking than the traditional teaching method. And the project approach was good for causing interest and helping student's science learning.

• Journal of Korean Neurosurgical Society
• /
• 제29권8호
• /
• pp.1055-1062
• /
• 2000

Objectives : Burst fracture of the lower lumbar spine(L3-L5) is rare and has some different features compare to that of thoracolumbar junction. Lower lumbar spine is flexible segments located deeply, and has physiologic lordosis. All of these contribute to making surgical approach difficult. Generally, lower lumbar burst fracture is managed either anteriorly or posteriorly with various fixation and fusion methods. But there is no general guideline or consensus regarding the proper approach for such lesion. We have tried to find out the influencing factors for selecting the surgical approach through the analysis of lower lumbar burst fractures treated for last 4 years(1994.3-1998.3). Method : This study includes 15 patients(male : 10, female : 5, age range 20-59 years with mean age of 36.7 years, L3 : 8 cases, L4 : 5 cases, L5 : 2 cases). Patients were classified into anterior(AO) and posterior operated(PO) groups. We investigated clinical findings, injured column, operation methods, and changes in follow-up radiologic study (kyphotic angle) to determine the considerable factors in selecting the surgical approaches. Results : There were 5 AO and 10 PO patients. Anterior operation were performed with AIF with Kaneda or Z-plate and posterior operation were done with pedicle screw fixation with PLIF with cages or posterolateral fusion. Canal compression was 46.6% in AO and 38.8% in PO. The degree of kyphotic angle correction were 10.7 degree(AO) and 8.5 degree(PO), respectively. There was no statistical difference between anterior and posterior operation group. All patients showed good surgical outcome without complications. Conclusion : Anterior operation provided good in kyphotic angle correction and firm anterior strut graft, but it difficulty arose in accessing the lesions below L4 vertebra. While posterior approach showed less correction of kyphotic angle, it required less time and provided better results for accompanied adjacent lesion and pathology such as epidural hematoma. The level of injury, canal compression, biomechanics, multiplicity, and pathology are considered to be important factors in selection of the surgical approach.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제33권6호
• /
• pp.631-635
• /
• 2007

Purpose: The classic technique for open reduction of subcondylar fractures is the submandibular approach. The aim of this study was to evaluate clinical result of retromandibular approach to displaced subcondylar fractures. Material and methods: During a period of 24months we perfomed a prospective study with a retromandibular approach in 23 patients with displaced subcondylar fractures. In this article we describe clinical result in 23 patients with follow ups for 3 months after surgery. Preoperatively all patients had malocclusion and radiology demonstrated displacement. Result: The retromandibularl approach for ORIF was good in all case. Mouth opening(M/O) was 49mm. Occlusion was good too. Permanent facial nerve palsy was not detected. Conclusion: Our findings indicate that the retromandibular approach is a safe technique for subcondylar fractures.

• 한국지능시스템학회:학술대회논문집
• /
• 한국퍼지및지능시스템학회 2007년도 춘계학술대회 학술발표 논문집 제17권 제1호
• /
• pp.305-308
• /
• 2007

In this paper we suggest an efficient evolutionary approach based on topological sort techniques for precedence constrained TSPs. The determination of optimal sequence has much to offer to downstream project management and opens up new opportunities for supply chains and logistics. Experimental results show that the suggested approach is a good alternative to locate optimal solution for complicated precedence constrained sequencing as in optimization method for instance.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2005년도 ICCAS
• /
• pp.1903-1906
• /
• 2005

We proposed a new variant of correlation approach for ARMA model. The proposed method is is intended to make the current prediction error uncorrelated with the past one. In the investigation of the properties, the uniqueness, consistency and asymptotic normality of the estimate are shown. Via simulation results, we show that the proposed method give good estimates for various systems.

• International Journal of Reliability and Applications
• /
• 제9권1호
• /
• pp.71-78
• /
• 2008

Based on the goodness of fit approach, a new test is presented for testing exponentiality versus exponential better (worse) than used (EBU (EWU)) class of life distributions. The new test is much simpler to compute, asymptotically normal, enjoys good power and performs better than previous tests in terms of power and Pitman asymptotic efficiencies for several alternatives.

• Earthquakes and Structures
• /
• 제13권2호
• /
• pp.131-136
• /
• 2017

This paper concerns two new analytical approaches for solving high nonlinear vibration equations. Energy Balance method and Hamiltonian Approach are presented and successfully applied for nonlinear vibration equations. In these approaches, there is no need to use small parameters to solve and only with one iteration, high accurate results are reached. Numerical procedures are also presented to compare the results of analytical and numerical ones. It has been established that, the proposed approaches are in good agreement with numerical solutions.

• 제어로봇시스템학회논문지
• /
• 제15권1호
• /
• pp.54-60
• /
• 2009

In this paper, a precision landing approach is implemented based on real-time image processing. A full-scale landmark for automatic landing is used. canny edge detection method is applied to identify the outside quadrilateral while circular hough transform is used for the recognition of inside circle. Position information on the ground landmark is uplinked to the unmanned helicopter via ground control computer in real time so that the unmanned helicopter control the air vehicle for accurate landing approach. Ground test and a couple of flight tests for autonomous landing approach show that the image processing and automatic landing operation system have good performance for the landing approach phase at the altitude of $20m{\sim}1m$ above ground level.

• Journal of Chest Surgery
• /
• 제26권6호
• /
• pp.492-495
• /
• 1993

We experienced one case of surgical treatment of abdominal aortic aneurysm using retroperitoneal approach. The transperitoneal route has been the standard surgical approach for elective and emergency treatment of aneurysmal or occlusive disease. Among its cited advantages for aortic reconstruction are familarity with the exposure, easy access to the infrarenal aorta and iliac vessels, possibility of simultaneous inspection of the intra-abdominal viscera, and speed of opening and closure.Despite the proved versatility of the transperitoneal approach, it is commonly associated with prolonged ileus, increased third space fluid loss, and significant pulmonary complications. The retroperitoneal approach, on the other hand, has many advantages; excellent exposure for the repair of juxtarenal or suprarenal abdominal aortic aneurysms and visceral vessel occlusive disease, fewer postoperative complications, decreased postoperative third-space fluid losses from intraoperative evaporation and ileus, and improved postoperative pulmonary function. Atherosclerosis was most common cause of abdominal aortic aneurysm. Dacron graft[18mm] was replaced successfully.Postoperative course was uneventful and he was discharged in good condition.

• 산업경영시스템학회지
• /
• 제36권1호
• /
• pp.24-35
• /
• 2013

A cell formation approach based on cluster analysis is developed for the configuration of manufacturing cells. Cell formation, which is to group machines and parts into machine cells and the associated part families, is implemented to add the flexibility and efficiency to manufacturing systems. In order to develop an efficient clustering procedure, this paper proposes a cluster analysis-based approach developed by incorporating and modifying two cluster analysis methods, a hierarchical clustering and a non-hierarchical clustering method. The objective of the proposed approach is to minimize intercellular movements and maximize the machine utilization within clusters. The proposed approach is tested on the cell formation problems and is compared with other well-known methodologies available in the literature. The result shows that the proposed approach is efficient enough to yield a good quality solution no matter what the difficulty of data sets is, ill or well-structured.