• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.552-554
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• 2004

Barrier ribs of plasma display panel (PDP) are glass matrix composite reinforced with alumina particles. Mechanical properties of the ribs are very crucial for the improvement in reliability of the panel as the ribs might fracture during transportation and service. In this study, therefore, the effects of filler type and content on the mechanical properties of the ribs were investigated. The fillers used include $Al_2O_3$, $TiO_2$, $ZrO_2$ and fused silica. The content of the filler was changed from 0 to 40 vol.%. The mechanical properties of the ribs measured were hardness, Young's modulus, fracture toughness, and 3-point bending modulus. The fracture toughness evaluated by micro-Vicker's indentation of the composites, in general, was measured to increase with the content of the filler until the sintered density does not decrease significantly. The improvement, however, was dependent on the type of filler employed.

• 한국국방경영분석학회지
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• 제2권1호
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• pp.177-184
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• 1976

As the organizational size of a military service or business increases and its management becomes complex, the success in its management depends less on static type of management but more on careful, dynamic type of management. In this thesis, an operations research technique is applied to the problems of determining optimal air traffic control rule and of optimal capacity of air base for a military air base. An airport runway is regarded as the service facility in a queueing mechanism, used by landing, low approach, and departing aircraft. The usual order of service gives priority different classes of aircraft such as landings, departures, and low approaches; here service disciplines are considered assigning priorities to different classes of aricraft grouped according to required runway time. Several such priority rules are compared by means of a steady-state queueing model with non-preemptive priorities. From the survey conducted for the thesis development, it was found that the flight pattern such as departure, law approach, and landing within a control zone, follows a Poisson distribution and the service time follows an Erlang distribution. In the problem of choosing the optimal air traffic control rule, the control rule of giving service priority to the aircraft with a minimum average waiting cost, regardless of flight patterns, was found to be the optimal one. Through a simulation with data collected at K-O O Air Base, the optimal take-off interval and the optimal capacity of aircraft to be employed were determined.

• 공업화학
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• 제29권3호
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• pp.356-361
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• 2018

혈액과 같이 다성분으로 이루어진 복잡한 matrix로 구성된 시료에서 휘발성 유기화합물(VOC)이나 반휘발성 유기화합물(SVOC)의 분석은 분리공정을 거쳐 분석되는 것이 일반적이다. 흡착은 어떤 성분이 다른 상의 표면에 축적되는 물리적 현상이다. 전처리 과정에서 번거로움을 극복하기 위해 흡착이 적용되며 이를 위해 다공성 탄소인 carboxen (CAR)이 도포된 solid phase microextraction (SPME) 장치가 흔히 사용된다. 본 연구에서는 플라스틱 제조시 가소제 등으로 사용되는 4-octylphenol의 carboxen에 대한 흡착특성을 살펴보았다. 이를 위해 dichloromethane ($CH_2Cl_2$, DCM), ethylacetate ($CH_3COOC_2H_5$, EA) 및 diethylether ($C_2H_5OC_2H_5$, $Et_2O$)에 대한 추출효율과 bistrimethylsilyltrifluoroacetamide (BSTFA), methylchloroformate (MCF) 및 pentafluorobenzylbromide (PFBBr)에 대한 유도체화 반응의 특성을 조사하였다. 열역학적 특성 파악을 위한 추출용제로는 DCM이 양호한 효과를 보였으며 BSTFA를 이용한 silylation의 분석특성이 우수하여 이를 적용하였다. 열역학적 및 동력학적 흡착실험 결과 흡착과정은 흡열특성을 보였고 Langmuir식보다는 Freundlich 등온식에 더 근접하였으며 동력학적으로는 pseudo-$2^{nd}$ order kinetic model에 따르는 것을 보였다.

• 한국정보과학회논문지:정보통신
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• 제32권2호
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• pp.254-260
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• 2005

보장서비스에서 실시간 패킷 스케줄링 알고리즘은 높은 네트워크 유용도와 확장성있는 구현의 양쪽 모두를 성취해야만 한다. 여기서 네트워크 유용도는 승인하는 실시간 세션의 수를 나타낸다. 불행히도, 현존하는 스케줄링 알고리즘은 확장성있는 구현에 문제점을 갖거나 성취할 수 있는 네트워크 유용도가 낮다. 가령 타임스템프에 기반한 알고리즘은 N이 세션의 수를 나타낼 때 O(log N) 스케줄링 복잡도를 가진다. 반면 라운드-로빈 알고리즘은 O(1) 복잡도를 가지지만 성취할 수 있는 네트워크 유용도가 낮다. 이 논문은 확장성을 잃지 않으면서도 높은 네트워크 유용도를 성취할 수 있는 스케줄링 알고리즘을 제안한다. 제안하는 알고리즘은 서로 다른 시간 구간 크기에 대해서 다중 라운드를 활용하는 계층적 라운드-로빈 (H-RR) 알고리즘이다. 이 알고리즘은 우선 순위 큐를 사용하는 PGPS 알고리즘이 제공하는 것과 비슷한 지연의 한계를 제공하지만, 구현 복잡도가 상수라는 큰 장점을 갖는다.

• 한국통신학회논문지
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• 제11권2호
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• pp.85-92
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• 1986

한글 Wordprocessor, Workstation 및 Telematics용 I/O Device에서는 각종 크기의 문자나 도형들을 요구하고 있다. 본 논문에서는 내장된 문자 dot pattern을 축소 또는 확대시키기 위하여 지금까지 연구되어온 각종 방식의 알고리즘을 논한다. 또한 문자 dot pattern의 크기를 변환시키는 방법을 평가하기 위한 항목을 논하며 이항목에 따라서 종래의 방식을 주관적으로 평가한다.

• 한국안전학회지
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• 제24권3호
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• pp.59-64
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• 2009

This study was conducted in order to investigate prevalence of musculoskeletal disorders(MSDs) for farmers. The study was based on self-reporting questionnaire. The MSDs prevalence was ascertained by using three criteria, which are known as NIOSH criteria 1, 2 and 3. The results showed that the prevalences of MSDs in at least one body site by criteria 1, 2 and 3 were 96.4%, 66.7% and 26.2%, respectively. The MSDs prevalences for the shoulder by criterion 1 was the highest, followed by the lower back, neck, while the rates for the hip, feet and fingers were relatively low. Farmers' age, types of corps, working hours/day, length of service and length of service in current corps were not significant on the MSDs prevalences, except that types of corps and length of service in current corps were significant on the MSDs prevalences by criterion 2(p

• Asia pacific journal of information systems
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• 제30권2호
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• pp.252-283
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• 2020

Online retail is a growing opportunity for retailers and consumers. Cross-buying provides companies with an opportunity to increase their revenue contributions from existing consumers. In many fields, especially in the service sector, cross-selling is an easier strategy to use relative to increasing revenue rather than acquiring new consumers. Website personalization has been a powerful indispensable tool for web-based companies and end users. Using the Mehrabian and Russell's Stimulus-Organism-Response framework, we experimentally examined how an online retailing merchant's environmental stimuli (S) arouses internal affective and cognitive states (O), that affect consumers' approach-avoidance behavior (R) in cross-buying and shopping cart abandonment in online transactions.

• 한국동물위생학회지
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• 제26권3호
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• pp.203-214
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• 2003

Scrub typhus and murine typhus are common endemic febrile illness in the fall in Korea. Scrub typhus is caused by Orientia tsutsugomushi, murine typhus is caused by Rickettsia typhi. Trombiculid mites are known as both the vector and the reservoir host of O tsutsugamushi, the mites which transmit O tsutsugomushi have been reported to be Leptotrombidium pallidum and L scutellare. The author carried out an epidemiological study of scrub typhus and murine typhus in Kyodong-Myeon, Kanghwa-Gun, Incheon in relation to the residents and the host rodents, such as their distribution, seroepidemiology, and population density of chigger mites. 1. Out of 900 residents, 33(3.7%) showed positive reaction to O tsutsugamushi, 24(2.7%) to R typhi. 2. In the seropositives to O tsutsugamushi or R typhi, between the sixties and the seventies of the age were dominant. 3. In the seropositives to O tsutsugamushi serotypically Gilliam was dominant. 4. Among the total 42 field rodents trapped by the sherman traps, 18 rodents were Apodemus agrarius(42.9%), 13 rodents were Crocidura lasiura(31.0%), 5 rodents were Musmusculus(11.9%), 2 rodents(4.8%) were Crocidura suaveolens, Rattus norvegicus, Tscherskia triton, respectively. 5. Out of 42 field rodents, 25 were parasitized by 4,419 chigger mites, showing 59.5% of the infestation rate and 98.8 of the chigger index. L pallidum parasitized in A agrarius, C lasiura, M musculus, R norvegicus and T triton, and L scutellare parasitized only C lasiura. 6. Antibodies in the sera of field rodents against O tsutsugamushi and R typhi were investigated by indirect immunofluorescent antibody technique. Positive rate of antibody against O tsutsugamushi were 11.9(5 of 42) and all of the positive is A agrarius. Antibody against R typhi was not detected. These results might provide the basic information for the management of scrub typhus and murine typhus in Kyodong-myeon, where the epidemiological studies on scrub typhus and murine typhus was not carried out enough.

• 한국자원식물학회지
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• 제27권2호
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• pp.174-182
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• 2014

본 연구는 희귀식물 연화바위솔과 희귀특산식물 울릉연화바위솔의 종 보존을 위해 양질의 규격묘 생산방법을 구명하고자 토양종류와 광 조건이 규격묘 생산에 미치는 영향을 살펴보았다. 그 결과 연화바위솔과 울릉연화바위솔 모두 클라스만 토양에서 우수한 생육특성을 나타냈다. 광 조건에 따른 연화바위솔의 생육특성은 무차광 처리와 적색과 청색 LED 혼합처리조건에서 우수한 생육특성을 보였으며, 울릉연화바위솔은 LED 혼합처리조건과 50% 차광처리조건에서 우수한 생육특성을 나타냈다. 울릉연화바위솔은 기간이 경과함에 따라 마사토에서 생존율이 통계적으로 유의성 있게 감소하였다. 각각의 생육특성과 생존율간의 상관분석 결과 연화바위솔은 초장과 엽장, 지상부생체중 사이에 0.8 이상의 상관관계를 나타냈다. 울릉연화바위솔도 초장과 엽폭, 엽장 사이에 0.8 이상의 상관관계를 보였으며, 초장과 지상부 생체중 사이에 0.65 이상의 상관관계를 나타내 초장이 지상부 생육특성을 대표한다는 것을 알 수 있었다. 특히 연화바위솔과 울릉연화바위솔 모두 1차 측정 생존율과 2차 측정 생존율 사이에 0.8 이상의 상관관계를 보여 초기 유묘 초장과 생존율 관리가 양질의 규격묘 획득에 가장 높은 영향을 미치는 것으로 나타났다. 따라서 연화바위솔과 울릉연화바위솔을 3월 중순에 파종하여 30일 후 지상부 2 mm, 지하부 3 mm 이상 되는 유묘를 클라스만 상토가 충진된 72구 트레이에 이식하고 적색과 청색의 LED 혼합처리조건에 35일 간 육묘하면 초장과 근장이 각각 2.5~4 cm, 3~5 cm 이상 되고 엽수가 11매 이상 되는 규격묘를 생산할 수 있는 것으로 나타났다.

• 한국동물위생학회지
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• 제30권2호
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• pp.191-196
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• 2007

The slaughter process for cattle will inevitably transfer some bacteria onto the carcasses. The goal of food safety programs is to minimize and effectively remove this contamination. This study was attempted by the Verif $EYE^{TM}$ machine-vision technology that might be useful for reducing microbial indicator counts and could reduce the contamination chance of E coli O157:H7 and Salmonella spp on beef carcasses. For the evaluation of the effectiveness of the Verif $EYE^{TM}$ technology, 80 samples were examined by the inspection device over 15 days. On an examination of FDS-positive samples compared to negative controls from the same carcasses, aerobic plate counts were bigger than the negative control samples (5.26 vs 4.60 log). Enterobacteriaceae counts were greater on the positive samples than the corresponding negative control samples (2.07 vs 1.17log). There was a consistent correlation between samples detected by the Verif $EYE^{TM}$ system with detectable counts. For example, 100% of positive samples had detectable APC and 91.2% of positive samples had detectable TCC. Therefore, if areas detected as positive for contamination by the Verif $EYE^{TM}$ system were removed from the carcasses, significant sources of microbial contamination will be reduced for objective compliance with HACCP. This results suggest that the use of Verif $EYE^{TM}$ machine-vision technology might be useful for reducing microbial indicator counts (APC, TCC) and could help reduce the risk of presence of E coJi O157:H7 and Salmonella spp on Beef carcasses.