• Journal of Astronomy and Space Sciences
• /
• v.30 no.1
• /
• pp.11-15
• /
• 2013

A collision-free formation reconfiguration trajectory subject to the linearized Hill's dynamics of relative motion is analytically developed by extending an algorithm for gravity-free space. Based on the initial solution without collision avoidance constraints, the final solution to minimize the designated performance index and avoid collision is found, based on a gradient method. Simple simulations confirm that satellites reconfigure their positions along the safe trajectories, while trying to spend minimum energies. The algorithm is applicable to wide range of formation flying under the Hill's dynamics.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 1998.06b
• /
• pp.67-72
• /
• 1998

The paper aims to present a new human-scale haptic advice for virtual environment named Scaleable-SPIDAR (Space Interface Device for Artificial Reality), which can provides different aspects of force feedback sensations, associated mainly with weight, contact and inertia, to both hands within a cave-like space. Tensioned string techniques are used to generate such haptic sensations, while keeping the space transparent and unbulky. The device is scaleable so as to enclose different cave-like working spaces. Scaleable-SPIDAR is coupled with a large screen where a computer generated virtual world is displayed. The used approach is shown to be simple, safe ad sufficiently accurate for human-scale virtual environment.

• Proceeding of Spring/Autumn Annual Conference of KHA
• /
• 2008.04a
• /
• pp.166-170
• /
• 2008

The elder population is growing rapidly in Korea nowadays. Therefore, a demand for adaptable installation standard of residential space for the elderly is increasing with growth of the elder population. This study analyzed actual state by interviewing manager, surveying actual measurement and using draft of Elderly nursing facility which is for senile patients. As a result of the survey for size and facilities, facilities for elderly safety, accommodation per a person and room size per a person are below to standard. Therefore, establishing adaptable design standard is needed which is to make safe and fresh living environment for the elderly.

• Clinical Endoscopy
• /
• v.56 no.1
• /
• pp.23-37
• /
• 2023

Submucosal endoscopy or third-space endoscopy utilizes the potential space between the mucosal and muscularis layers of the gastrointestinal tract to execute therapeutic interventions for various diseases. Over the last decade, endoscopic access to the submucosal space has revolutionized the field of therapeutic endoscopy. Submucosal endoscopy was originally used to perform endoscopic myotomy in patients with achalasia cardia, and its use has grown exponentially since. Currently, submucosal endoscopy is widely used to resect subepithelial tumors and to manage refractory gastroparesis and Zenker's diverticulum. While the utility of submucosal endoscopy has stood the test of time in esophageal motility disorders and subepithelial tumors, its durability remains to be established in conditions such as Zenker's diverticulum and refractory gastroparesis. Other emerging indications for submucosal endoscopy include esophageal epiphrenic diverticulum, Hirschsprung's disease, and esophageal strictures not amenable to conventional endoscopic treatment. The potential of submucosal endoscopy to provide easy and safe access to the mediastinum and peritoneal spaces may open doors to novel indications and rejuvenate the interest of endoscopists in natural orifice transluminal endoscopic surgery in the future. This review focuses on the current spectrum, recent updates, and future direction of submucosal endoscopy in the gastrointestinal tract.

• KIEAE Journal
• /
• v.12 no.5
• /
• pp.53-61
• /
• 2012

As aging society progresses, it is necessary to establish a housing standard that provides a healthy, safe, and convenient environment for the elderly. The objective of the study is to propose a housing space standard that is geared towards elderly living in the urban area. Three steps were taken to attain the objective. First, characteristics of housing preference, spatial usage and furniture preference of the elderly were attained through a survey. The survey was conducted targeting the respondents of the ages 60 to 79 living in three different administrative districts in Seoul. Second, the required floor space to perform individual specific behavior using anthropometric dimension of the elderly was investigated by literature review. Lastly, floor space of each space is suggested combining each area for individual specific behavior which reflects characteristics of housing preference and spatial usage. The results of the research as follows. A bedroom was planned, which includes the function of receiving guests by giving the area for the placement of a sofa. The space for the use of dinning table for two person was planned in the kitchen and The space for the behavior of showering on a chair was planned in a bathroom. Lastly, the space for the behavior of taking off shoes on a chair was considered in the entrance area. Consequently, $35.4m^2$ is suggested as the necessary floor space for the elderly housing considering the characteristics of the elderly in urban area. However, because of space composition and space for accessibility, the additional space should be considered to plan the elderly housing.

• Journal of Korean Neurosurgical Society
• /
• v.29 no.10
• /
• pp.1396-1401
• /
• 2000

Although direct surgical treatment of the lesion in the pons may cause severe neurologic morbidity, safe route to minimize injuries of the important structures in the pons should be considered. The authors operated four cases of intrapontine lesions via safe approach route without causing severe neurologic complications. Two cases were intrapontine tumors and other two were intrapontine hematoma. An anaplastic astrocytoma($3{\times}3{\times}3cm$) located bilaterally in the pons was approached via midline of the median sulcus, and a metastatic tumor($1.5{\times}1.5{\times}1.5cm$) located at the left posterolateral aspect in the upper pons was approached via suprafacial space. Two cases of hematoma were evacuated via median sulcus, and supra- and infrafacial spaces. Preoperatively, quadriplegia, swallowing difficulty, diplopia, speech disturbance, and nystagmus were noted in a patient with an anaplastic astrocytoma. A patient with metastatic tumor showed mild right hemiparesis, right hemisensory disturbance, diplopia, and dizziness. Two patients with hematoma in the pons were comatous, and had contracted, fixed pupils. Postoperatively, a patient with an anaplastic astrocytoma recovered and a patient with a metastatic tumor showed temporary hemifacial palsy. Mental status was fully recovered normal even though facial palsy, diplopia, severe ataxia, dizziness, and tremor persisted in both patients with pontine hematoma. Careful operation based on the anatomical knowledge of the floor of the 4th ventricle is of prime importance in appraoching to the intrapontine lesion with minimal injuries of the eloquent structures during surgery.

• Korean Institute of Interior Design Journal
• /
• v.23 no.4
• /
• pp.169-180
• /
• 2014

Since Seoul city supplied 'Sangsang Children's Park', domestic children's parks are changing from formal facilities to creative play space recently. From eco-friendly safe playground model development project, the awareness of eco-friendly playground, namely children's park is increasing and its necessity is magnified. However, we could not know how well most children's parks aimed at the eco-friendly playground reflect eco-friendly features and whether they are eco-friendly or not because there are not the specific planning guidelines and evaluation standards for making the eco-friendly playground or children's park. Therefore, in this study we established the environment-friendliness evaluation standards of children's parks and estimated the environment-friendly features of the 9 parks built on the subject of green among Sangsang Children's Parks. In the observational survey of the 9 parks, we evaluated the environment-friendliness of these parks in the 8 fields(location and placement, ecological environment, play space, play equipment and facilities, additional facilities, materials and resources, energy saving, environmental load reduction) according to the levels(suitable, partial reflection, unsuitable, non-reflection) of reflection of eco-friendly planning factors. The assessment results showed that 4 items (location and placement, additional facilities, play space, play equipment and facilities) were suitable and others (energy saving, environmental load reduction, ecological environment, materials and resources) were partial reflection or unsuitable. Therefore, on the basis of these results, this study proposed the planning indicators to be considered first and the planning factors that should be complemented and improved in the construction of eco-friendly children's park in future.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2001.10a
• /
• pp.128-131
• /
• 2001

The purpose of this study is to investigate the application of Column Jet Method(CJM) as countermeasure against settlement and slope sliding of existing marine structure due to embankment load behind reclaimed revetment. CJM is to make high-strengthened body by compacting and grouting cement mortar after forming artificial space in the ground with ground relaxition machine or high pressure water jetting. Before the ground was reinforced by CJM, the result of slope stability analysis was not satisfy the allowable safe ratio, but after the ground was reinforced by CJM, the stability of slope was over the allowable safe ratio and stable, Therefor, the application of CJM to restraint settlement and sliding of marine structure was very satisfactory.

• Journal of the Korea Construction Safety Engineering Association
• /
• s.50
• /
• pp.84-96
• /
• 2009

Road is typically constructed along ridge area of mountain because of topographical and economic reasons. Therefore, road may face lots of open cut slope which can easily cause rock falling. This study evaluates the structural safety of newly developed falling rock protection system which has a roof deck plate. The structural performance under self-weight, snow load and load from failing rock was investigated using a finite element numerical analysis method. From the analysis results, the H-beam space was limited not to exceed 2.2m. The deck plate was also safe under the examined loading condition. A hinge and connection in the system were investigated through detailed modelling and analysis. The results showed that the hinge was safe enough and that the connection should strengthened with appropriate stiffeners.

• The Journal of Sustainable Design and Educational Environment Research
• /
• v.9 no.2
• /
• pp.9-18
• /
• 2010

The school is the educational and living space for students and teachers. And, the safety of the school facilities is very important element on the school activities. For this safety of school facilities, there is a need to prevent of safety-accident by the reinforcement of the systematic and the removal of risk factors. In order to minimize the damages from school facilities this study tried to suggest the solution for the prevention of safety accidents according to research about actual conditions of safety accidents from school facilities.