• Information Systems Review
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• v.7 no.1
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• pp.115-136
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• 2005

Recently Internet portals contend with each other to expand their customer base by providing customers with a much amount of e-mail storage. But This strategy may not be successful because of customers' switching cost following site moving. Therefore, in order to reveal whether their strategy makes sense, this study investigates the direct and contingency factors affecting customer switching intension of e-mail services in portal sites. The research results show that attractiveness of alternatives, switching cost, and customer satisfaction have a significantly direct impact on customer switching intension of e-mail services. Also, attractiveness of alternatives alone has an moderated effect on customer switching intension but switching cost does not. Thus, Internet portals may reap the harvest from their recent aggressive action.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1995.04a
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• pp.196-201
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• 1995

The broadband and discrete sources of sound in small cooling fans of propeller type and centrifugal type were investigated to understand the turbulent vortex structures from many bladed fans using ANSI test plenum for small air-moving devices (AMDs). The noise measurement method uses the plenum as a test apparatus to determine the acoustic source spectral density function at each operating conditions similar to real engineering applications based on acoustic similarity laws. The characteristics of fans including the head rise vs. volumetric flow rate performance were measured using a performance test facility. The sound power spectrum is decomposed into two non-dimensional functions: an acoustic source spectral distribution function F(St,.phi.) and an acoustic system response function G(He,.phi.) where St, He, and .phi. are the Strouhal number, the Helmholtz number, and the volumetric flow rate coefficient, respectively. The autospectra of radiated noise measurements for the fan operating at several volumetric flow rates,.phi., are analyzed using acoustical similarity. The rotating stall in the small propeller fan with a bell-mouth guided is mainly due to a leading edge separation. It creates a blockage in the passage and the reduction in the flow rate. The sound power levels with respect to the rotational speeds were measured to reveal the mechanisms of stall and/or surge for different loading conditions and geometries, for example, fans installed with a impinging plate. Lee and Meecham (1993) studied the effect of the large-scale motions like impinging normally on a flat plate using Large-Eddy Simulation(LES) and Lighthill's analogy.[ASME Winter Annual Meeting 1993, 93-WA/NCA-22]. The dipole and quadrupole sources in the fans tested are shown closely related to the vortex structures involved using cross-correlations of the hot-wire and microphone signals.

• Proceedings of the KWS Conference
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• 2010.05a
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• pp.74-74
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• 2010

모바일 정보통신기기를 중심으로 전자패키지의 초소형화, 고집적화를 위해 플립칩 공법의 적용이 증가되고 있는 추세이다. 플립칩 패키징 접합소재로는 솔더, ICA(Isotropic Conductive Adhesive), ACA(Anisotropic Conductive Adhesive), NCA(Non Conductive Adhesive) 등과 같은 다양한 접합소재가 사용되고 있다. 최근에는 언더필을 사용하는 플립칩 공법보다 미세피치 대응성을 위해 NCP를 이용한 플립칩 공법에 대한 요구가 증가되고 있는데, NCP의 상용화를 위해서는 공정성과 함께 신뢰성 확보가 필요하다. 본 연구에서는 LDI(LCD drive IC) 모듈을 위한 COF(Chip-on-Film) 플립칩 패키징용 NCP 포뮬레이션을 개발하고 이를 적용한 COF 패키지의 신뢰성을 조사하였다. 테스트베드는 면적 $1.2{\times}0.9mm$, 두께 $470{\mu}m$, 접속피치 $25{\mu}m$의 Au범프가 형성된 플리칩 실리콘다이와 접속패드가 Sn으로 finish된 폴리이미드 재질의 flexible 기판을 사용하였다. NCP는 에폭시 레진과 산무수물계 경화제, 이미다졸계 촉매제를 사용하여 다양하게 포뮬레이션을 하였다. DSC(Differential Scanning Calorimeter), TGA(Thermogravimetric Analysis), DEA(Dielectric Analysis) 등의 열분석장비를 이용하여 NCP의 물성과 경화거동을 확인하였으며, 본딩 후에는 보이드를 평가하고 Peel 강도를 측정하였다. 최적의 공정으로 제작된 COF 패키지에 대한 HTS (High Temperature Stress), TC (Thermal Cycling), PCT (Pressure Cooker Test)등의 신뢰성 시험을 수행한 결과 양산 적용 가능 수준의 신뢰성을 갖는 것을 확인할 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.11
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• pp.1634-1640
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• 2012

The objective of this study was to compare pork characteristics and to determine consumer acceptability of pork chops from antibiotic free Yorkshire crossbreds sired by Berkshire (BY), Large Black (LBY), Tamworth (TY) or Yorkshire (YY) boars and reared in hoop houses. The experiments were conducted at the North Carolina Agricultural and Technical State University (NCA&TSU) Farm in Greensboro, NC and the Cherry Research Station Center for Environmental Farming Systems (CEFS) Alternative Swine Unit in Goldsboro, NC (source of antibiotic free Yorkshire sows used at both places). Twenty-four sows were artificially inseminated at each location in each of three trials. Litters were weaned at 4 wks old, and reared within deep-bedded outdoor hoop houses. To compare pork characteristics, 104 randomly selected animals were harvested at a USDA-inspected abattoir at approximately 200 d of age. Variables measured included pH, color score, $L^*$, $a^*$, $b^*$, marbling score, drip loss, hot carcass weight, backfat thickness (BF), loin muscle area (LMA), and slice shear force. Sensory panel tests were also conducted at two time periods. The data was analyzed with GLM in SAS 9.01 including location, trial, and sire breed as fixed effects. Backfat thickness, LMA, color score and $a^*$ were different among breeding groups (p<0.05). The LBY pigs had thicker backfat and smaller LMA than the other breed types. The TY and YY had less backfat than all other breed groups. Color score was lower for YY than BY and LBY but intermediate for TY. The $a^*$ was lower for TY than other breeds except LBY which was intermediate. For one sensory panel test, YY pork was more preferred overall as well as for juiciness and texture compared to BY and LBY (p<0.05), but no impact of breed type was noted for the other test, with values similar for BY, LBY, TY and YY pork. This information may help small farmers make decisions about breed types to use for outdoor production.

• International Commerce and Information Review
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• v.6 no.2
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• pp.107-127
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• 2004

The rapid development of internet information technology has increased interest in e-Trade these days, but it is not activated greatly up to now. In order to promote e-Trade, it is essential to construct cooperative process such as connecting systems among trade related parties. Building e-Trade platform which is based on the infrastructure of the past trade automatic system is key point of promoting e-Trade. To do this, a study on the basic concept and specific components of e-Trade platform is needed absolutely. At this point of view, after this paper has examined domestic and foreign studies on the fundamental technologies about electronic commerce, it drew several key technologies that could be applied to e-Trade considering the current IT trend. Then it evaluates these technologies according to Technology Reference Model(TRM) of the National Computerization Agency. This will help us to show the operation strategy as well as the concept of future e-Trade platform and its composition. On the basis of the theoretical background, this paper classified NCA's technology model into 6 fields, which are application. data, platform, communication, security and management. Considering the key technologies, e-Trade platform has to be mutually connected and accept international standards such as XML. In the aspect of business side, trade relative agencies' business process as well as trading company's process has to be considered. Therefore, e-Trade platform can be classified into 3 parts which are service, infrastructure and connection. Infrastructure part is compared of circulating and managing system of electronic document, interface and service framework. Connecting service (application service) and additional service (application service) consist of service part. Connecting part is a linking mutual parts and can be divided into B2B service and B20 service. The organization operating this e-trade platform must have few responsibilities and requirements. It needs to positively accept existing infrastructure of trade automatic system and improving the system to complete e-trade platform. It also have to continuously develop new services and possess ability to operate the system for providing proper services to demanders. As a result, private sector that can play a role as TTP(Third Trust Party) is adequate for operating the system. In this case, revising law is necessary to support the responsibility and requirement of private sector.

• Journal of Forest and Environmental Science
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• v.33 no.4
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• pp.342-347
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• 2017

Since the first report of the oak wilt disease at 2004 in Korea, the disease distributed over Korean peninsula and are still giving severe damages. The management of oak wilt disease in Korea has mainly focused on the control of insect vector, Platypus koryoensis. Neverthless the effective method for evaluating the pathogenicity of the pathogen, Raffaelea quercus-mongolicae (Rqm), and for screening chemical or biological agents with strong inhibitory activity against the pathogen, is absolutely necessary, an reliable method is not available so far. This study was conducted to develop the effective method for evaluating the pathogenicity of Rqm in oak trees. The culture suspensions of Rqm were artificially injected to the saplings of Quercus acutissima by using ChemJet tree injector. Three months after treatments, the treated saplings were cut and dipped into 1% fuchsin acid solution. There were significant differences in non-conductive area (%), discoloration area (%) and vertical discoloration length between the pathogen-injected and distilled water-injected control treatments. These results indicated that the pathogen is the causal agent for the dysfunction of water conductive tissue, which will finally result in wilt symptom. Re-isolation of the pathogen and PCR detection using specific primers for the pathogen also confirmed the presence of Rqm in the sapwood chips of the pathogen-injected saplings. These observations would be greatly applied to other related researches for evaluating the pathogenicity of tree wilt pathogens and biocontrol efficacy of the selected antagonistic microorganisms, in case that the wilt symptom is not easily shown by artificial inoculation of the causal agent.

• Korean Journal of Comparative Education
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• v.24 no.3
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• pp.245-265
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• 2014

The purpose of this research is to find the features of HLC institutional accreditation model and the implication on the second period institutional accreditation of Korea. This research focus on accreditation model, accreditation period, comprehensive evaluation, criteria, decision making for accreditation status and accreditation supporting system. This research draws following suggestions to the second period institutional accreditation of Korea. 1. The institutional accreditation should apply various accreditation models according to the features of institute. 2. The institutional accreditation should focus on the autonomous quality improvement of institute with the quality assurance. 3. The quantitative evaluation should be reduced and qualitative evaluation based on mission and objects should be reinforced. 4. The interim evaluation should be strictly enforced for quality improvement. 5. The government should enlarge reflection the results of accreditation on financial aid to universities. 6. The web-based accreditation supporting system interworking with "Higher Education in Korea" service is needed.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.36 no.1
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• pp.50-63
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• 2023

Objectives : This study used a network pharmacology approach to explore the active compounds and therapeutic mechanisms of Yijin-tang on Meniere's disease. Methods : The active compounds of Yijin-tang were screened via the TCMSP database and their target proteins were screened via the STITCH database. The GeneCard was used to establish the Meniere's disease-related genes. The intersection targets were obtained through Venny 2.1.0. The related protein interaction network was constructed with the STRING database, and topology analysis was performed through CytoNCA. GO biological function analysis and KEGG enrichment analysis for core targets were performed through the ClueGO. Results : Network analysis identified 126 compounds in five herbal medicines of Yijin-tang. Among them, 15 compounds(naringenin, beta-sitosterol, stigmasterol, baicalein, baicalin, calycosin, dihydrocapsaicin, formononetin, glabridin, isorhamnetin, kaempferol, mairin, quercetin, sitosterol, nobiletin) were the key chemicals. The target proteins were 119, and 7 proteins(TNF, CASP9, PARP1, CCL2, CFTR, NOS2, NOS1) were linked to Meniere's disease-related genes. Core genes in this network were TNF, CASP9, and NOS2. GO/KEGG pathway analysis results indicate that these targets are primarily involved in regulating biological processes, such as excitotoxicity, oxidative stress, and apoptosis. Conclusion : Pharmacological network analysis can help to explain the applicability of Yijin-tang on Meniere's disease.

• Steel and Composite Structures
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• v.49 no.4
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• pp.457-471
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• 2023

To make up for the performance weaknesses of recycled aggregate concrete (RAC), expand the application range of RAC, and alleviate the environmental problems caused by excessive exploitation of natural coarse aggregates (NCA), this study proposes a basalt fiber-reinforced recycled aggregate concrete (BFRRAC)-filled square steel tubular columns that combines two modification methods of steel tube and fiber, which may greatly enhance the mechanical properties of RAC. The axial compression performance for BFRRAC-filled square steel tubular columns was reported during this study. Seven specimens with different replacement ratios of recycled coarse aggregate (RCA), length-diameter ratios, along with basalt fiber (BF) contents were designed as well as fabricated for performing axial compression test. For each specimen, the whole failure process as well as mode of specimen were discovered, subsequently the load-axial displacement curve has obtained, after which the mechanical properties was explained. A finite element analysis model for specimens under axial compression was then established. Subsequently, based on this model, the factors affecting axial compression performance for BFRRAC-filled square steel tubes were extended and analyzed, after which the corresponding design suggestion was proposed. The results show that in the columns with length-diameter ratios of 5 and 8, bulging failure was presented, and the RAC was severely crushed at the bulging area of the specimen. The replacement ratio of RCA as well as BF content little affected specimen's peak load (less than 5%). As the content of BF enhanced from 0 kg/m³ to 4 kg/m³, the dissipation factor and ductility coefficients increased by 10.2% and 5.6%, respectively, with a wide range.

• The Korean Journal of Nuclear Medicine
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• v.36 no.5
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• pp.298-305
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• 2002

Purpose: Bone marrow scintigraphy has been used to evaluate the status of bone marrow in various hematologic disorders. We have analyzed the peripheral distribution pattern and central uptake ratio of bone marrow using anti-NCA-95 monoclonal antibody and the their correlation in patients with various hematologic malignancy. Materials and Methods: Bone marrow immunoscintigraphy was performed using Tc-99m anti-granulocyte monoclonal mouse antibody BW 250/183. Fifty patients were classified into four groups; 11 with acute myelogenous leukemia, 12 with acute lymphocytic leukemia, 15 with lymphoma and 12 with myelodysplastic syndrome. The extension of peripheral bone marrow was categorized into four grades: I, II, III and IV. The activity of central bene marrow was expressed as sacroiliac uptake ratio. Results: The patient's number was 4 in grade I, 27 in grade II, 15 in grade III and 4 in grade IV according to extension of peripheral bone marrow. The extension of peripheral bone marrow was marked (58% in grade III and IV) in myelodysplastic syndrome and acute lymphocytic leukemia and mild (93% in grade I and II) in lymphoma. Sacroiliac uptake ratio was highest ($8.5{\pm}4.0$) in myelodysplastic syndrome and lowest ($5.9{\pm}3.6$) in acute myelogenous leukemia, but not significantly different among four patient groups (p>0.05). Sacroiliac uptake ratio of whole patients was significantly different among four grades (p=0.003), but there was not correlated between grade of peripheral bone marrow and sacroiliac uptake ratio (r=0.05). Conclusion: The pattern of peripheral bone marrow extension and activity of central hemopoietic marrow were not specific to the disease entities. Response of hemopoietic bone marrow may be evaluated on both peripheral and central bone marrow in patients with hematologic malignancy.