• Asian-Australasian Journal of Animal Sciences
• /
• v.21 no.3
• /
• pp.353-357
• /
• 2008

A series of studies has been conducted to establish a base infrastructure for an ovarian follicle culture system in the porcine and this study was designed to develop an effective retrieval protocol of preantral follicles. Five different methods using collagenase type I (A) or IV (B, C1, C2 and C3), which employed different treatment durations and/or conditions, were employed and sliced ovarian tissue of prepubertal gilts was provided for the retrieval. A significant increase in total number of follicles retrieved was detected when collagenase IV (methods B or C) was used. In total, more ovarian follicles were retrieved by method B undertaking agitation and method C2 without the agitation than method C1 and C3, while the number of preantral follicles collected was the largest in method B. Neither incubation in 5% $CO_2$ in air atmosphere instead of the agitation nor increased duration of enzymatic treatment up to 120 minutes improved the efficiency of follicle retrieval. There were no differences in the number of follicles retrieved from intact ovaries and from used ovaries for oocyte collection. These results demonstrate the collagenase IV treatment with agitation is effective for retrieving porcine preantral follicles from the ovaries.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2007.02a
• /
• pp.97-100
• /
• 2007

본 논문은 유비쿼터스 센서 네트워크와 텔레매틱스 서비스에 사용되는 무선 환경 프로토콜 표준 중 UHF 대역 프로토콜인 EPCglobal의 Class 1 Gen 1, Class 1 Gen 2의 에어인터페이스를 분석하고 각 프로토콜에서 규정된 충돌방지 알고리즘을 구현하였다. 그리고 각 프로토콜에서 규정하는 충돌방지 알고리즘의 성능을 개선한 알고리즘을 제안하고 성능을 비교하였다. 개선된 알고리즘과 표준 알고리즘의 성능 시뮬레이션 결과 개선된 Class 1 Gen 1 알고리즘은 태그 수 100개 일 때 54.5%, 태그 수 1000개 일 때 63.4% 감소하였다. 개선된 Class 1 Gen 2 알고리즘은 태그 수 100개 일 때 7.9%, 태그 수 1000개 일 때 11.7% 감소하였다. 개선된 충돌방지 알고리즘은 표준 알고리즘보다 태그 인식 성능이 상당히 개선됨을 알 수 있다. 따라서 개선된 충돌방지 알고리즘은 유비쿼터스 센서 네트워크와 텔레매틱스 서비스 등에 사용되는 무선인식 시스템의 성능 개선방안으로 적용될 수 있다.

• 한국생물공학회:학술대회논문집
• /
• 2005.10a
• /
• pp.456-462
• /
• 2005

The objective of this study was to develop a removal process by which $H_2S$ could be biologically removed from the odoriferous gases generated in the waste food recycling process. In order to develop this process we were first required to select a proper biofilter support protocol. When the selected biofilter equipment was then tested suing a synthetic odoriferous gas containing 600 ppm of $H_2S$, we noted a maximal removal rate of 658 $g-H_2S/m^3{\cdot}hr$, using polypropylene fibrils as supporting materials. Under identical experimental conditions, we obtained a value of 411.2 $g-H_2S/m^3{\cdot}hr$, using polyurethane as a support material. We also conducted a trial in which volcanic stone was utilized as a support material, and in this trial, we logged a maximal 105.1 $g-H_2S/m^3{\cdot}hr$ removal rate. As the result of our experiments, we concluded that polypropylene fibrils constituted the ideal material for the removal of $H_2S$ gas via biological treatment.

• Proceedings of the SAREK Conference
• /
• 2009.06a
• /
• pp.1343-1347
• /
• 2009

In order to comply with the global energy crisis and environment problem, it is necessary to research and develop the energy utilization technology with the reduction of the primary energy usage. Although the increasing rate of energy consumption started to attenuate, the entire consumption of energy as well as $CO_2$ emission rate tends to increase steadily along with an economic growth in Korea. The energy demand in Korea increases by annual 3.7% during the period from 2000 to 2006. And it is expected that we should take a charge of the greenhouse gas reduction obligation by the Climatic Change Convention(Kyoto Protocol) during the 2nd pledge period($2013{\sim}2017$). According to the IEA report in 2005, the emission amount of carbon dioxide is the 10th place in the world, and the increasing rate is 4.7% annually. Considering the economic scale of Korea, the degradation of energy usage is inevitable when the greenhouse gas reduction obligation come into effect. Therefore, effective energy usage is a very important issue to minimize baneful influence on industrial and economic activities.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.53
• /
• pp.265-288
• /
• 2012

Trade in service, which deals with intangible product, is distinguished from trade of goods for tangible product. The current multilateral service trade is based on GATS which includes MFN, securing the predictability as well as transparency of related service rules, specific commitment basis market access national treatment. Recently the WTO service disputes are increasing according to the frequent filing complaints against the regulation of service trade in China. The rules of GATS are not as strict as those of GATT. The commitment schedules, which were materialized between members, gets binding effect through the obligatory provisions of GATS. The GATS is inseparable relation with the Appendix of finance, of telecommunication, and of air transport, with the schedules of commitment of member states, and with the reference paper to the 4th protocol. GATS article XIV which is the general exception of GATS has a similar structure of GATT article XX. Based on the possibility of filing to the WTO, there is a need to examine whether the whole rules, regulation, and policy international trade in service of Korea perfectly macthed with the GATS. Korea with poor resources should take up the more positive attitude for the opening of international service market. According to the reciprocal aspects of concession, if Korea doesn't open a service market, the other WTO member country wouldn't allow Korea to access the their market as well as national treatment.

• Journal of Advanced Navigation Technology
• /
• v.15 no.2
• /
• pp.241-247
• /
• 2011

Most of network congestions are caused by TCP packet losses in the wired network ecosystems. On the contrary, high BER (Bit Error Rate), which is characteristic of the wireless networks, is a main factor in wireless network environments. Many wireless networks carry out the congestion control mechanisms frequently because they estimate that packet losses are not due to the wireless signal qualities but the congestion controls in their networks. To solve this problem, we propose the improved EWLN (Explicit Wireless Loss Notification) algorithm that more efficiently utilize the congestion window size to increase the wireless network throughput than legacy EWLN algorithm.

• Proceedings of the KSR Conference
• /
• 2008.06a
• /
• pp.2455-2462
• /
• 2008

Global warming has become one of the most important social responsibilities. After Kyoto protocol for greenhouse gas reduction by climatic change convention came into effect, developed countries are presenting various policies to reduce greenhouse gas that is produced in transport field. One of those policies is modal shift that change from road freight to sea, inland waterway and railway transportation that is eco-friendly. Because increase of road freight brings about road congestion and accident, logistics cost, air pollution and green house gases. Railways are superior to all other modes of transport in mass transportability, high speed, timeliness, safety and environmental-friendliness, but the railway industry has been pushed behind in competition. In developed country's government actively promoted relevant legislation, policies, and countermeasures known as modal shift policies to shift freight transport from road to large volume mode such as railway and ship. In this paper, we discuss the current situation in modal shift, compare it with cases in other countries EU and Japan, identify problems in Korea, and propose the following ways to enhance competitiveness of rail freight.

• Korean Journal of Cleft Lip And Palate
• /
• v.11 no.1
• /
• pp.13-22
• /
• 2008

Velopharyngeal insufficiency(VPI), characterized by hypernasal resonance and nasal air emission, is a speech disorder that can significantly compromise speech intelligibility. Cleft palate, previously repaired cleft palate and submucous cleft palate are associated with VPI. Less commonly, patients may acquire it after adenoidectomy with or without tonsillectomy or as a result of neuromuscular dysfunction. Comprehensive evaluation by a VPI team includes medical assessment focusing on airway obstructive symptoms, perceptual speech analysis, MRI and instrumental assessment. Options for intervention include speech therapy, intraoral prosthetic devices and surgery. Surgical methods can be categorized as palatal, palatopharyngeal or pharyngeal procedures. Each surgical approach has its strengths and limitations. Oro-maxillofacial surgeons are increasingly involved in the referral, evaluation, and treatment of velopharyngeal function. Therefore, understanding of physiology, anatomic structures, evaluation and treatment protocols in VPI is very important. This article presents protocol for evaluation of velopharyngeal function with a focus on indications for surgical interventions.

• Proceedings of the SAREK Conference
• /
• 2007.11a
• /
• pp.149-154
• /
• 2007

Now, in Korea, the performances of the building service equipment relay on the individual superintendent's share for the assessment of performance, fault detection, deterioration diagnosis of the building service equipment. As the result, very different quality of the performance or the durability of equipment is being obtained with his skill and effort and it is also not easy to assess that quality. This finally lead to the waste of labor force and the operating cost due to the high-cost, low-efficiency system. How to construct the N-BMS was considered to save energy, resource and to conserve performance of building service equipment. The FEMIS, facility, energy/environmental management & information system, for building service offer management process integrated with BAS, FMS and EMS and so on.

• Fisheries and Aquatic Sciences
• /
• v.25 no.8
• /
• pp.429-440
• /
• 2022

This study assessed the effects of oxygen and ozone nanobubbles on gill morphology, weight gain, and mortality of Pacific white shrimp (Penaeus vannamei), as well as the level of Vibrio parahaemolyticus and water quality of shrimp culture tanks under lab conditions. Two experiments were carried out with oxygen macrobubble, ozone macrobubble, oxygen nanobubble, ozone nanobubble, and control treatments (air-stone macrobubble). Experiments were done in triplicate in 100 L tanks with 15‰ saline water, and 20 shrimp per tank. Tanks in Experiment 1 were not inoculated with bacteria; tanks in Experiment 2 were inoculated with V. parahaemolyticus at a concentration of 10⁶ CFU/mL. The results revealed that short treatments with ozone nanobubbles had minimal impact on shrimp gills, mortality, and growth rates, reduced V. parahaemolyticus concentration in water compared to the other groups, and improve water quality. These laboratory results indicate that ozone nanobubble treatment may be useful for controlling V. parahaemolyticus. More work is needed to find the best protocol to apply the technology on a commercial scale.