• 한국정보통신설비학회:학술대회논문집
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• 2008.08a
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• pp.372-375
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• 2008

IEEE 802.11e standardized the EDCA mechanism to support the priority based QoS. And the virtual collision handler schedules the transmission time of each MAC frame using the internal back-off window according to the access category(AC). This can provides the differentiated QoS to real-time services at the medium traffic load condition. However, the transmission delay of MAC frame for real-time services may be increased as the traffic load of best effort service increases. It becomes more critical when the real-time service uses a compressed mode video codec such as moving picture experts group(MPEG) 4 codec. That is because each frame has the different importance. That is, the I-frame has more information as compared with the P- and the B-frame. In this paper, we proposed a buffer management algorithm based on the frame importance and the delay bound. The proposed algorithm is consisted of the traffic regulator based on the dual token bucket algorithm and the active queue management algorithm. The traffic regulator reduces the transmission rate of lower AC until that the virtual collision handler can transmit an I-frame. And the active queue management discards frame based on the importance of each frame and the delay bound of head of line(HoL) frame when the channel resource is insufficient.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.1
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• pp.12-22
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• 2000

This paper presents the window-based permit distribution scheme for efficient medium access control to support multiclass traffic in APON(ATM over passive optical network). The proposed MAC protocol considers the characteristics of QoS(Quality of Service) for various traffic classes. A periodic RAU(request access unit) in upstream direction, includes dedicative request fields for each traffic category within the request slot. The transmission of upstream cell is permitted by the proposed window-based spacing scheme which distributes the requested traffic into several segments in the unit of one spacing window. The delay sensitive traffic source such as CBR or VBR with the stringent requirements on CDV and delay, is allocated prior to any other class. In order to reduce the CDV, so that the permit arrival rate close to the cell arrival rate, Running-Window algorithm is applied to permit distribution processing for these classes. The ABR traffic, which has not-strict CDV or delay criteria, is allocated flexibly to the residual bandwidth in FIFO manner. UBR traffic is allocated with the lowest priority for the remaining capacity. The performance of proposed protocol is evaluated in terms of transfer delay and 1-point CDV according to various offered load. The simulation results show that our protocol has the prominent improvement on CDV and delay performance with compared to the previous protocol.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.1
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• pp.127-133
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• 2013

The present study, the determinants of Lease-hold of the commercial real estate needs, interior and facilities, transit Lumpur, Daehangno and Dongsoong analysis of a questionnaire survey of mall tenant sales, density results affects the biggest presence, sales, traffic, density, the interior and facilities, and the impact was negligible. Also analyzed as a result of analysis of gender, age, education, Category, income differences combination of external factors and internal factors impact on key money that This result provides a new founder and stores the previous tenants want to contribute to the success of your business.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.742-749
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• 2006

For the purpose of finding if aircraft noise annoyance response is affected to variables when noise survey is performed, the questionnaire survey is conducted around the Gimpo International Airport in Seoul, Republic of Korea. This residential area is exposed to the aircraft noise and road traffic noise, simultaneously. Research areas are classified according to three different aircraft noise exposure levels expressed in WECPNL, under 75, between 75 and 80, and above 80 WECPNL, on aircraft noise map. The 7-step numerical magnitude with verbal category scales is used to measure the annoyance level. This surrey suggests that aircraft noise annoyance is not affected to an important extent by other noise sources (road traffic noise, community noise) and demographic variables (sex, age, education, occupation, dwelling type, length of residence). Aircraft noise annoyance would be related to complaint activity which is one of attitudinal variables.

• Journal of Korean Medicine Rehabilitation
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• v.23 no.4
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• pp.233-250
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• 2013

Objectives The purpose of this study was to investigate the characteristics of inpatients who were admitted to Korean medicine hospital due to traffic accident. Methods 1,162 traffic accident patients who were admitted to department of Korean Rehabilitation Medicine of Cheonan Korean Medicine Hospital, Dae-Jeon University from 1st, January, 2011 to 31th, December, 2012 were analyzed according to the medical charts. Results 1. The average treatment result was 3.22 and in most (71.52%) of the patients, symptoms were more than improved. 2. In distribution according to age and sex, people in their 30s numbered the most both in male (12.65%) and female (14.72%). The 1,162 inpatients comprised of 457 (39.33%) male and 705 (60.67%) female. 3. 541 (46.56%) patients admitted in 2011 and 621 (53.44%) patients admitted in 2012. 4. 695 (59.81%) patients visited Cheonan Korean Medicine Hospital within 0~2 days after their traffic accident, followed by 242 (20.83%) patients who visited within 3~5 days after their traffic accident. Patients who admitted earlier showed more improvement in symptoms. 5. The average admission days were 9.32 days. Most (57.66%) patients discharged within 1 week. 6. 825 (71.00%) patients were driving sedan at the time of accident, followed by 105 (9.04%) SUV owners and 71 (6.11%) pedestrians. 7. Rear-end collision accident numbered the most (45.61%), followed by lateral collision (24.35%) and frontal collision (14.72%). 8. Most frequently prescribed examination was X-ray (95.52%), followed by CT (8.69%) and MRI (3.01%). 9. Most frequently given diagnosis was sprain (1,126 (96.90%) patients), followed by concussion & abrasion (178 (15.32%) patients) and fracture (109 (9.38%) patients). 10. Most frequently given Korean medicine treatment was acupuncture (1,162 (100%) patients), followed by anti-inflammatory pharmacopuncture (652 (56.11%) patients) and moxibustion (462 (39.76%) patients). 11. Most frequently given Korean medicine physiotherapy was infra-red (1,161 (99.91%) patients), followed by cupping therapy (1,152 (99.14%) patients) and hotpack (1,137 (97.85%) patients). 12. Most frequently prescribed herb medicine was huishou-san (13.51%), followed by dangguixu-san (12.65%) and yaojiao-tang G (7.06%) Conclusions In this study, people in their 30s, females, within 0~2 days since the accident took the highest percentage from each category of patients who admitted to Korean Medicine Hospital due to traffic accident. Patients who admitted earlier showed more improvement in symptoms and also discharged earlier.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1591-1601
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• 2013

In this study, It is conducted for novice drivers about driving behavior and psychological characteristics analysis to reduce traffic accident risk and provide the basic data of education program development. Therefore, this study classified by the category-specific characteristics and hazard prediction through survey of the novice driver and unpredictable behavior and psychological characteristics were studied. The novice and general characteristics and driving behavior with vehicle simulators, comparison and analysis of the novice driver traffic safety education basic research direction based on the statistical results. Prediction the results of this study, the Hazard of the driver, speeding, traffic violation, information providing omission, abrupt change, the number of accidents in all areas novice driver is high compared to the general driver. In addition, Novice driver showed a statistically significant level of Hazard compared to the general driver target novice drivers and the general ability to predict Hazard of violation, abrupt change, and a number of traffic accidents were omitted level of speeding and other information providing level drivers all showed similar results. Vehicle simulator. The experimental results showed that novice drivers compared to drivers poorly overall driving performance. It showed a notable difference in the number of collisions, especially novice drivers compared to drivers in complex road traffic conditions due to a lack of driving experience and learning ability are considered.

• Journal of Acupuncture Research
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• v.33 no.4
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• pp.15-31
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• 2016

Objectives : The aim of this study is to review the instruments used to assess patient condition and the effects of Korean medical treatment for patients injured in traffic accidents in clinical studies in the Korean medical field published in South Korea. Methods : A literature study was performed, and clinical studies on patients injured in traffic accidents visiting Korean medical clinics or hospitals were examined. Data about chief complaints, tools used to assess either patients' condition or the effectiveness of Korean medical treatment, and time point of assessment were extracted. The studies were classified according to symptom. The use-frequency and the parent category of the assessment tools were also analyzed. Results : 78 studies were selected and classified into 5 categories based on the chief complaints, neck pain, lower back pain, headache, psychological symptoms and unspecified symptoms. Various scales were used to report the patient's pain severity, and functional or psychological status resulting from traffic accidents. Pain index, in particular VAS, was most frequently used and a few mechanical instruments and Korean medicinal assessment tools were mentioned. Conclusion : Most instruments used in Korean medicine clinical studies on patients injured in traffic accidents are self-reported tools. To assess both the patient's condition precisely and the effectiveness of Korean medical treatment on patients injured in traffic accidents, more appropriate and unified tools should be designed that consider pain, functional disability, psychological status and objective assessments measured by devices together.

• Korean Security Journal
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• no.23
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• pp.21-39
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• 2010

The dangerous impact on the traffic flows of cars is caused by no only the construction on the street but diverse construction sites. This in turn substantially influence on the citizens and pedestrians, thereby bring about the possibility of giant incidents. As the countermeasure for the problem in advanced countries, particularly in Japan "traffic inducement security system" has been implemented. It is analyzed that the death toll from traffic accidents has considerably declined. In the case of South Korea the system has not been administered but restrictively executed at some construction sites; however proceeding it with the lack of professionalism. The introduction of traffic inducement security system would be the opportunity for South Korea to make a progress in the safety culture such as traffic security and traffic jam. This study thus aims at analyzing the advanced countries' cases, conducting comparative analysis with Korea's scheme, and establishing the plan to adopt the traffic inducement security system. Through the output of this study followings were proposed as plans of introducing the traffic inducement security system. First of all, legal assessments regarding traffic inducement operation, for example adding the operation of the system into the category of security service, need to be preceded prior to its introduction secondly, the traffic inducement security is the institution which can contribute to the improvement of traffic safety, and also internalizing social cost. therefore, it needs to be equipped with the new qualification such as the instruction with the standardized traffic safety map, instruction system, curriculum and the publication of teaching materials. thirdly, the education for the guard should be proceeded with dividing academic and technical ones with specific curriculum. At the fourth, the securement of the venue for the driving training, the determination on technical instruction contents and the training professional instructor needs for the method of administration. In addition, the efforts on the overal standardization of traffic inducement security is necessary, and it also requires constant collaboration among private security industry, academia, professionals, relavant research institutes, etc. At the last but the least, henceforth it is prerequisite that the networking system with a diverse array of associated entities due to its social ripple effect and job creation effect.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.4
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• pp.454-465
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• 2012

The Korean government decided to reduce 30% of GHG (greenhouse gas) emissions BAU in 2020. Since many efforts to reduce emissions are urgently needed in Korea, the central administrative organization urges local governments to establish their own reduction schemes. Among many GHG emission categories, the emission from mobile source in Gyeonggi Province accounted for 25.3% of total emissions in 2007 and further the emission from road transport sector occupied the most dominant portion in this transportation category. The objective of this study was to compare 3 types of GHG emissions from road transport sector in 31 local cities/counties of Gyeonggi Province, which have been estimated by Tier 1, Tier 2, and Tier 3 methodologies. As results, the GHG emission rates by the Tier 1 and Tier 2 were $19,991kt-CO_2\;Eq/yr$ and $18,511kt-CO_2\;Eq/yr$, respectively. On the other hand, the emission rate by Tier 3 excluding a branch road emission portion was $18,051kt-CO_2\;Eq/yr$. In addition, the total emission rate including all the main and branch road portions in Gyeonggi Province was $24,152kt-CO_2\;Eq/yr$, which was estimated by a new Tier 3 methodology. Based on this study, we could conclude that Tier 3 is a reasonable methodology than Tier 1 or Tier 2. However, more accurate and less uncertain methodology must be developed by expanding traffic survey areas and adopting a suitable model for traffic volumes.

• Land and Housing Review
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• v.1 no.1
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• pp.113-124
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• 2010

This study is evaluating that new hi-tech transit systems each type of function and introduce applicable guideline decreases land sale price in New town and Large scale land development projects. For this, use the look-up table through the composite category of each type of system at the functional types, local characteristics. It also, As introduce the new systems calculate the Social benefits such as altered public traffic transfer system, reduced transit time and reduced carbon emission considering the three-dimensional arterial roads. As a result, New transportation systems contribute that the more reducing traffic congestion and air pollution and municipalities seeks for environment-friendly policy. However, this paper emphasize that the new transportation system has been introduce without considering the characteristics of locality and the efficient arrangement of them, it cannot be transferred the to the existing public traffic efficiently, futhermore causes the sale price in new large scale land development projects.