• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.35 no.4
• /
• pp.907-920
• /
• 2015

By increase owning vehicle, infrastructure that accept vehicle is very poor on present that People's commuting is rapidly change to vehicle-use-form in metropolitan area. Although Transportation demand management is enforced, traffic is heavy but studies lake in internal and external. This study select Transportation demand management that enforce in internal and external and do a survey. Based on this survey, conduct AHP (Analytic Hierarchy Process) analvsis, Transportation demand management that enforce internal and external compare, decide superiority and understand every particular items' importance and satisfaction that users think. Also based on importance that collect by AHP analysis compare Transportation demand management character. Finally figure that grasped by this study, analysis present, found future TDM course and applicate future transportation improvement.

• Journal of the Korea Furniture Society
• /
• v.26 no.1
• /
• pp.61-70
• /
• 2015

There is an increasing trend each year in the number of subway users due to increase in the traffic volume. As the number of train service has risen, the subway drivers are given heavy work and from the same, are put at risk of mental health deterioration due to stress. As this is directly connected to safety, there is an urgent need for improvement of the situation. Therefore, as a way to appropriately relieve such stress, resting space where mental and physical energy can be recharged is necessary. Thus, this research conducted a survey of demand with subway drivers as subjects in order to provide resting space that can offer healthy rest and increase work effectiveness. 50 subway drivers were the subjects of this survey. As a result of analyzing the contents of the survey, environmental satisfaction was shown to be the lowest compared to psychological and morphological satisfaction. In the case of sleeping room, they wanted more comfortable and individual space. And the waiting room had the highest rate of usage frequency. The storage space was where the subway drivers showed the strongest attachment and was shown to be the only personal space. Most were shown to be satisfied with the outdoor space, but it had the lowest usage frequency. In addition, it is nessasery customized storage cabinet designed for subway drivers should be produced, which can effectively arrange the limited space. I hope that these direction of improvement can increase the healthy rest and work effectiveness of the locomotive engineers as it is directly being connected to the health and safety of the citizens.

• The Transactions of the Korea Information Processing Society
• /
• v.7 no.12
• /
• pp.3964-3975
• /
• 2000

There are two policies for maintaining consistency among the multiple processor caches in a multiprocessor system: Write invalidate and Write update. In the write invalidate policy, whenever a processor attempt to write its cached block, it has to invalidate all the same copies of the updated block in the system. As a results of this frequent invalidations, this policy results in high cache miss ratio. On the other hand, the write update policy renew them, instead of invalidating all the same copies. This policy has to transfer the updated contents through interconnection network, whether the updated block is ptivate or not. Therefore the network suffer from heavy transaction traffic. In this paper we present an efficient cache coherence protocol for shared memory multiprocessor system connected by slotted ring. This protocol is based on the write update policy, but the updated contents are transferred only in case of updating the shared block. Otherwise, if the updated block is private, the updated contents are not transferred. We analyze the proposed protocol and enforce simulation to compare it with previous version.

• The Journal of the Acoustical Society of Korea
• /
• v.19 no.2
• /
• pp.46-53
• /
• 2000

In coastal bay waters, bubbles are generated by relatively heavy ship-traffic, breaking waves due to man-made structures and biological activities. Therefore, the bubble-generating mechanism as well as the bubble density distribution in the bay are quite different from the open ocean where breaking waves are major contributor for bubble density distribution. High frequency surface-backscattered signals were obtained in the coastal bay waters and they were analyzed to compare with those from the open waters in terms of the sea-surface backscattering strength at various grazing angles, the reverberation characteristics in the sub-surface layer and spectral spreading of the scattered signals. The results show that, the surface scattered signals have an irregular distribution of amplitude in time and the width of the spectral spreading is wider than that of the open sea with rough surface. Furthermore, the amplitude distribution of the reverberation signals is not following the Rayleigh distribution, that is eon to be a typical pattern for the open ocean. The results of our analysis imply that the bubble size and the bubble density in the bay are quite different from those observed in the open waters.

• Korean Journal of Health Education and Promotion
• /
• v.6 no.1
• /
• pp.91-105
• /
• 1989

The purpose of this study is to identify the body images of patints with low back pain and their status on adjustment of daily living. The data were collected from 11 general hospitals during Feburary 2, 1987 through May 30,1987. One hundred and ninety five subjects having physical therapy treatment because of low back pain were analyzed. For measurement of body image, 11 pairs of adjectives were used on semantic differential scale, and for measurement of adjustment of daily living, 10 items were used on a likert type scale. Results of the study are summerised as follows. 1. The average patient age were 34yeats and 62% of the patients were men. High school grade completed were 43.1% and Cause of Low Back Pain were respctively;Unknown etiology 31.8%, lifting heavy objects 27.7%, Traffic accident and injury 17.9%. Types of treatment were;medication plus physical therapy 54.9%, physical therapy only 22.6%. Average treatment duration were 24.5 months. 2. There were significant difference in the body image between before low back pain and after low back pain. The body image before low back pain were 59.89(Mean) but after low back pain were 37,24(Mean) and two groups were statistically significant (t=21.3, p<0.00l). 3. there were no significant difference in the body image between the male and female.(t=1.49, p＞0.05) 4. The correlation between body image and adjustment of daily living. in both sexes showed positive correlation coefficient; male(r=0.4648, p<0.00l) female(r=0.4516, p<0.00l) respectively. It means that patients with positive body image can adjust well in daily living. 5. The relation between the body image and general variables revealed sigificant difference with occupation and age.(F=2.12 p<0.05, F=3.48 p<0.05). That is different occupation and different age groups can show different body image. In conculsion with the above results, It is my strong belief that multidisciplinary approach including the concept of body image and patient education about postural care, activities of daily living, lifting mechanics should be applied in treating and dealing with those patients.

• International Journal of Highway Engineering
• /
• v.6 no.2 s.20
• /
• pp.37-45
• /
• 2004

The asphalt concrete pavement takes various advantages of better riding quality, serviceability and easier maintenance. At the same time, it addresses a weak point of the premature failures due to rapid increasement of traffic volume, heavy vehicles and high temperature in summer. It increases the expenditure of maintenance and repair. In order to improve the performance of asphalt pavement avoiding this premature failure, the use reinforcements with geosynthetics have been considered. Geosynthetics are known as an effective reinforcement to restrain fatigue and reflective cracks in asphalt pavements. In this study, a comprehensive parametric study is conducted to capture the efficiency of geosynthetic-reinforcements using viscoelastic properties of the asphalt concrete(AC) layer. The investigated parameters were reinforcement location, AC layer thickness, temperature distribution across the AC layer and modulus of AC and base layer. As a result of observations, that reinforced asphalt concrete could be used effectively for improving resistance against fatigue cracks and permanent deformation. Especially, when a geogrid was placed at the interface between the asphaltic base and the subbase, tensile stress in the horizontal direction was significantly reduced.

• Journal of Korean Society of Transportation
• /
• v.22 no.2 s.73
• /
• pp.109-119
• /
• 2004

In COSMOS, an area for signal coordination is divided into subareas composed of several signalized intersections that share a common cycle time. Each subarea contains only one critical intersection having heavy traffic load. Subarea is a basic unit of control. The performance of COSMOS is highly dependent on the linkage rule between adjacent subareas. The purpose of this study is to provide an appropriate subarea linkage rule in COSMOS. This study developed a control strategy for Critical Intersection and Sub Area linkage. Critical Intersections calculate the Offset Pattern both East-West Axis and North-South Axis, and the coordination direction either East-West Axis or North-South Axis. Subarea can be combined with other one in all directions. The performance of the suggested linkage rule was evaluated on the real network in Gangnam-Gu. The result was that travel time was reduced by the suggested linkage rule.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.37 no.3
• /
• pp.603-610
• /
• 2017

Various type of pavement deterioration such as crack, bumpy, pothole is rapidly increasing according to the accelerated environmental changes like heavy rainfall, frequent snowing, difference temperature, etc. Accident related to pothole that cause fatal traffic accidents has been increased more than five times over the next five years starting from 2008. As direct or indirect damage by pothole which caused injuries and car damages increases every year, quicker and more efficient management measures are necessary. This study presents the algorithm for materials quantity take-off. The algorithm was suggested by correlation in pothole size and area. Suggested algorithm were confirmed the validity through the 15 field survey in capital area. According to the results of survey, usually the residual materials at which 5~7 kg was generated decreased to 1~2 kg. It showed that automatic pothole detection system is expected not only to reduce materials and resources, but also to contribute to quality improvements of pavement through more accurate material take-off from the situation of constructing rely on their own judgement.

• Asian Journal of Atmospheric Environment
• /
• v.12 no.3
• /
• pp.204-214
• /
• 2018

Indoor air quality was investigated in homes and daycares located in areas with heavy traffic in Seoul, South Korea from November 2013 to January 2014. Indoor and outdoor air quality measurements were collected for 48 hours in four children's homes and daycare centers. The I/O ratio (Indoor to outdoor ratio) for each major air pollutant ($NO_2$, black carbon, $PM_{10}$, and $PM_{2.5}$) was calculated, and $NO_2$ and $PM_{10}$ concentration profiles were analyzed based on indoor activity diaries recorded during the 48 hours. Most I/O ratios for $NO_2$, black carbon, $PM_{10}$, and $PM_{2.5}$ at daycare centers were less than one. At homes, I/O ratios for black carbon, $PM_{10}$, and $PM_{2.5}$ were less than one; however, most I/O ratios for $NO_2$ were greater than one due to the usage of gas stoves. The children's exposure to indoor air pollutants was calculated using a time-weighted average exposure method, and the daily intake level for each pollutant was determined.

• Journal of KIISE:Computing Practices and Letters
• /
• v.15 no.9
• /
• pp.675-684
• /
• 2009

Internet worm can cause a traffic problem through DDoS(Distributed Denial of Services) or other kind of attacks. In those manners, it can compromise the internet infrastructure. In addition to this, it can intrude to important server and expose personal information to attacker. However, current detection and response mechanisms to worm have many vulnerabilities, because they only use local characteristic of worm or can treat known worms. In this paper, we propose a new framework to detect unknown worms. It uses macroscopic characteristic of worm to detect unknown worm early. In proposed idea, we define the macroscopic behavior of worm, propose a worm detection method to detect worm flow directly in IP packet networks, and show the performance of our system with simulations. In IP based method, we implement the proposed system and measure the time overhead to execute our system. The measurement shows our system is not too heavy to normal host users.