• Proceedings of the Korea Multimedia Society Conference
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• 2002.05c
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• pp.390-395
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• 2002

MPLS는 고속 전달, 트랙픽 엔지니어링 그리고 가상 사설망 서비스를 가능하게 한다. MPLS 레이블 스위치와 제어기 사이에서 동작하는 GSMP 프로토콜은 연결, 구성, 장애, 성능관리 및 동기화 기능을 제공하는 개방형 인터페이스 프로토콜이다. GSMP가 적용된 개형형 인터페이스의 망 관리 기능은 제어기 또는 레이블 스위치에 위치할 수 있다. 본 논문에서는 MPLS 레이블 스위치의 단순화 및 자원 이용의 효율성을 높이기 위하여 SNMP 에이전트가 제어기에 탑재되는 망 관리 모델을 제시하였다. MPLS-LSR 및 FTN MIB와 GSMP 메시지의 매핑 시나리오를 제시하였으며, 제어기의 구현을 통하여 본 논문에서 제시된 망 관리 모델의 실현성을 확인하였다.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.71.1-71.1
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• 2010

고분자 전해질 연료전지(PEMFC) 내의 기체확산층(GDL)은 셀 내의 물 관리에 중요한 역할을 수행한다. 일반적으로 다공성 기제(GDBL) 위에 미세기공층(MPL)을 코팅한 2층 구조의 기체확산층이 사용되는데, 이 미세기공층은 카본파우더와 테프론의 혼합물로 이루어져 있으며 촉매층에서 발생한 물을 셀 밖으로 빠르게 배출하는 역할을 수행한다. 본 연구에서는 다양한 기공분포를 갖는 미세기공층을 제조하여 고분자 전해질 연료전지 성능에 미치는 영향을 분석하였다. 미세기공층 슬러리내에 암모늄염 계열의 기공형성제를 혼합하여 다공성 기제 위에 코팅한 후 다양한 온도조건에서 건조함에 따라 기공분포가 다른 미세기공층을 제조하였다. 이렇게 제조된 미세기공층의 물성은 수은기공도계, FE-SEM, 자체적으로 제조한 기체투과도 측정 장치를 사용하여 측정하였으며, 단위 전지 성능 측정은 두 개의 가습조건(RH100%, RH50%)에서 실시하였다. 기공분포 측정결과 건조온도가 높은 미세기공층은 건조온도가 낮은 미세기공층에 비해 직경이 1,000 - 20,000 nm 인 대공극(macropore)의 수가 많지만, 직경이 100 nm 이하의 미세공 (micropore)의 수가 적은 것을 확인하였다. 전지성능 측정 결과 고가습 조건 (RH100%)에서는 미세공 (micropore)이 발달한 미세기공층을 포함한 기체확산층을 사용한 경우 가장 우수한 성능을 보여고, 저가습 조건 (RH50%)에서는 대공극 (macropore)이 발달한 미세기공층을 포함한 기체확산층을 사용한 경우 가장 우수한 성능을 나타내었다. 이는 물배출에 유리한 미세공 (micropore)의 성질과 원료 기체의 이동에 유리한 대공극(macropore)의 성질에 의한 것으로 판단된다. 따라서 셀 운전 가습조건에 따라 최적화된 기공구조를 갖는 미세기공층을 사용함으로써 셀 운전 성능을 향상 시킬 수 있을 것으로 예상된다.

• Journal of Veterinary Clinics
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• v.37 no.3
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• pp.135-140
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• 2020

The purpose of this study was to determine the outcome of distal femoral osteotomy for distal femoral varus and medial patellar luxation (MPL) grade 4 in small-breed dogs. Radiographs and medical records were reviewed to collect data and plan the surgery in small-breed dogs with MPL grade 4. Computed tomography (CT) imaging was also performed in cases of severe bone deformities. Signalment, weight, medial patellar luxation and lameness grade, radiographic bone union, complications, pre- and postoperative femoral varus angle, passive range of motion, static weight bearing distribution and visual analogue scale scores were recorded. Thirteen corrective distal femoral osteotomies were performed with ancillary and additional procedures in 9 dogs; 4 dogs had staged bilateral procedures; and four stifles were suspected to have partial or complete rupture of the cranial cruciate ligament. One stifle underwent patellar groove replacement. The mean ± SD pre- and postoperative femoral varus angles were 109.15°± 3.71° and 96.30°± 2.97°, respectively. Significant improvements in passive range of motion, thigh circumference and visual analogue scale (VAS) scores were observed. There was no reluxation of the patella. This study suggests that distal femoral osteotomy with traditional and additional procedures provided satisfactory outcomes in patient healing and functional recovery in small-breed dogs with excessive femoral varus angles.

• Journal of Hydrogen and New Energy
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• v.24 no.3
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• pp.216-222
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• 2013

Durability characteristics of Gas Diffusion Layer(GDL) is one of the important issues for accomplishing commercialization of Proton Exchange Membrane Fuel Cell(PEMFC). It is strongly related to the performances of PEMFC because one of the main functions of GDL is to work as a path of fuel, air and water. When the GDL does not work on their proposed functions due to the degradation of durability, mass transfer in PEMFC is disturbed and it might cause the flooding phenomenon. Thus, investigating the durability of GDL is important and understanding the GDL degradation process is needed. In this study, electrochemical degradation with carbon corrosion is introduced. The carbon corrosion experiment is carried out with GDLs which have different MPL penetration thicknesses. After the experiment, the amount of degradation of GDL is measured with various properties of GDL such as weight, thickness and performance of the PEMFC. The degraded GDL shows loss of their properties.

• Journal of Food Hygiene and Safety
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• v.15 no.3
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• pp.179-185
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• 2000

Daily intakes of 14 preservatives were evaluated by using their maximum permitted levels(MPL) and national food disappearance data in 1998. The estimated daily intake (EDI) of each preservatives were compared with corresponding acceptable daily intakes (ADIs). EDIs of dehydroacetic acid, sodium dehydroacetate, $\rho$-hydrobenzoic acid ester, propionic acid, sodium propionate and calcium propionate were less than 2% of ADI and judged to be safe. However, EDI of sorbic acid and potassium sorbate were 76.61 mg/person/day and it reached 5% of its ADI.. EDI of benzoic acid and sodium benzoate were 85.65 mg/person/day and it reached 31% of its ADI. The highest intake of benzoic acid came from carbonated drink.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.5
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• pp.133-142
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• 2004

Recently, the growth of Internet and a variety of multimedia services through Internet increasingly demands high-speed packet transmission, the new routing function, and QoS guarantee on conventional routers. Thus, a new switching mechanical called the MPLS(Multi-Protocol Label Switching), was proposed by IETF(Internet Engineering Task Force) as a solution to meet these demands. In addition the deployment of MPLS network supporting Differentiated Services is required. In this paper, we propose the architecture of the MPLS switch supporting Differentiated Services in the MPLS-based network. The traffic conditioner consists of a classifier, a meter, and a marker. The VOQ-PHB module, which combines input Queue with each PHB queue, is implemented to utilize the resources efficiently. It employs the Priority-iSLIP scheduling algorithm to support high-speed switching. We have designed and verified the new and fast hardware architecture of VOQ-PHB and the traffic conditioner for QoS and high-speed switching using NS-2 simulator. In addition, the proposed architecture is modeled in VHDL, synthesized and verified by the VSS analyzer from SYNOPSYS. Finally, to justify the validity of the hardware architecture, the proposed architecture is placed and routed using Apollo tool.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.3
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• pp.330-339
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• 2002

Fifty one Nili-Ravi dairy buffaloes in their last two months of gestation were selected. After parturition, rectal examination of reproductive organs was carried out until the occurrence of the first oestrus (PEI). Milk samples were analyzed for milk progesterone levels (MPL). Ovulation (POI) was confirmed by rectal palpation and MPL. Feed and blood samples were collected fortnightly and analyzed. Body condition score (BCS) was recorded on a scale of 0 to 5. Crude protein (CP) intake varied among different seasons and correlated positively with serum urea levels, POI (p<0.01) and PEI (p<0.05). Excess CPI was lower in the group showing oestrus as compared to those remaining as anoestrus (p<0.05). The dietary ratio of crude protein - metabolizable energy (CP:ME) in the oestrus animals was narrow and constant, while the anoestrus animals had a widely fluctuating one. In normal breeding season (NBS) calvers, mean serum urea level (SUL) was lower than the low breeding season (LBS) calvers. SUL was positively correlated with PEI and POI (p<0.01). Up to six months postpartum, SUL were constantly higher in anoestrus than oestrus buffaloes. Mean metabolizable energy (ME) intake was lower in the NBS calvers than the LBS calvers (p<0.01). BCS and postpartum ovulation interval were correlated with ME intake (p<0.01). Prepartum ME intake was higher in oestrous as compared to anoestrous animals (p<0.05). Higher and lower ME intakes were associated with anoestrus, while a moderate energy intake was associated with a PEI of less than 75 days. Buffaloes with poor BCS belonged to the LBS calving group and most of the NBS calving buffaloes had good BCS. BCS was negatively correlated with PEI (p<0.01) and was higher in oestrous buffaloes than anestrus. It was concluded that excess intake of crude protein, associated with higher serum urea levels and low energy intake, associated with poor body condition, are the key factors for low reproductive efficiency. It may be corrected by adopting a proper feeding strategy.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.6 s.324
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• pp.41-48
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• 2004

In an IP network, various types of traffics are statistically multiplexed to utilize efficiently the network resources. The DiffServ-aware-MPLS supports a wide variety of communication services with different QoS requirements. The DiffServ-aware-MPLS based on QoS architecture had become one of the most promising ways to guarantee QoS MulIti-service IP network. But how to manage IP network with QoS guarantee is still an open issue. In this paper, we propose DiffServ-aware-MPLS buffer management technique using the specified policing, queuing, and scheduling.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.1B
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• pp.71-79
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• 2003

As the traffic grows rapidly in the Internet, the QoS guarantee of the flows and the traffic engineering problems have become very important issues. MPLS has more advantages to solve the problems than existing IP routing because of its use of multiple paths between the source and destination pairs Particularly, the availability of Constraint-based Shortest Path First(CSPF) algorithm and explicit route in MPLS made the problem referred above to be solved efficiently. However, the CSPF algorithm has the characteristic of selecting the shortest path of all paths which meet the traffics' QoS constraints Therefore, even though there are alternative paths to route traffic, alternate QoS paths may not be found and best-effort traffic will be dropped during congestion period In this paper, we present the network resource optimization method related to the traffic engineering by using load balancing through routing in MPLS network.

• Journal of KIISE:Information Networking
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• v.29 no.1
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• pp.57-64
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• 2002

Since most of the current route selection algorithms use the shortest path algorithm, network resources can not be efficiently used also traffics be concentrated on specific paths resulting in congestgion. In this paper we propose the statistical route selections(SRS) algorithm which adopts a statistical mechanism to utilize the network resource efficiently and to avoid congestion. The SRS algorithm handles requests on demand and chooses a path that meets the requested bandwidth. With the advent of the MPLS it becomes possible to establish an explicit LSP which can be used for traffic load balancing. The SRS algorithm finds a set of link utilizations for route selection, computes link weights using statistical mechanism and finds the shortest path from the weights. Our statistical mechanism computes the mean and the variance of link utilizations and selects a route such that it can reduce the variance and the number of congested links and increase the utilization of network resources. Throughout the simulation, we show that the SRS algorithm performs better than other route selection algorithms on several metrics like the number of connection setup failures and the number of congested links.