• Journal of Biosystems Engineering
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• 제39권1호
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• pp.11-20
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• 2014

Purpose: Walking type cultivator used for weeding generated excessive handle vibration as well as bouncing motion depending on the weeding speed. This research was conducted to define a design factor of the rotary weeding blades for reducing soil reaction forces as well as hand vibration. Methods: The motion and forces acting on the rotary blades were reviewed to find out the most influencing parameter on hand vibration. The installation angle (IA) of the blade was selected and analyzed to determine the condition of no reaction force less. For removing the unnecessary upward soil reaction, the design factor theory of weeding blade was suggested based on geometrics and dynamics. For evaluation of design factor theory, the experiment in situ was performed base on ISO 5349:1. The vibration $a_{hv}$ and theoretical value $X_{MF}$ were compared with two groups that one was positive group ($X_{MF}$ > 0) and the other was negative group ($X_{MF}$ < 0). Results: $X_{MF}$ was derived from rotational velocity, forward velocity, disk diameter, weeding depth, blade's width and IA of blade. Two groups had significant difference (p < 0.05). In aspect of the group mean total exposure duration, positive group was 17.53% bigger than negative group. When disk radius 100, 150 and 200 mm, minimum IAs were $4{\sim}27^{\circ}$, $3{\sim}15^{\circ}$ and $2{\sim}10^{\circ}$, respectively. A spread sheet program which calculated XMF was developed by Excel 2013. Conclusions: According to this result, minimum IA of weeding blade for soil reaction reduction could be obtained. For reduction hand-arm vibration and power consumption, minimum IA is needed.

• 정보처리학회논문지C
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• 제9C권3호
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• pp.385-398
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• 2002

제한된 라디오 스펙트럼에서 증가하는 이동 단말기의 수에 따라 서비스를 제공하기 위해서, 무선 시스템은 마이크로/피코 셀룰러 구조와 같이 설계되어야 한다. 이와 같이 다수의 사용자를 수용하기 위하여 셀 크기를 축소하게 되면 핸드오프 이벤트가 증가하게 되며, 안정적인 서비스를 제공하기 위해 효과적 처리해 줄 수 있는 핸드오프 기술이 필수적이라 할 수 있다. Population-Based Bandwidth Reservation(PBR) 구조는 한 셀(Cell)의 이웃에 있는 셀 들에게 셀룰러 트래픽의 양에 따라 대역폭의 양을 동적으로 조절함으로써 핸드오프 호(Hand-off Call)들에게 우선 순위를 제공하는 구조이다. 본 논문에서는 어떤 기간에 발생하는 핸드오프 호에 요구되는 전체 대역폭에 대한 요청 예약 비율을 나타내는 Fractional Parameter, f의 변화에 따라 PBR 구조의 성능을 분석하였다. 파라미터 f의 값은 QoS(Quality of Service) 요구에 따라 결정되어지며, 요구사항을 충족시키기 위하여 변화하는 트래픽 상태에 따라 동적으로 조절된다. f의 최적값은 이동국(Mobile Station)의 속도, 평균 호의 기간, 셀 크기 등에 따라 결정되어진다. 본 논문에서는 이동국의 속도에 따라서 평균 호의 기간과 셀 크기를 가정하였다. 속도에 따라서 약간의 타이가 나지만, 0.4 $\leq$ f $\leq$ 0.6인 경우에서 Blocking Probability, Dropping Probability, Utilization이 최적인 값을 가지게 된다.

• 대한치과보철학회지
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• 제39권2호
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• pp.220-229
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• 2001

This study was performed to evaluate the fracture resistance of three improved die stone materials according to water/powder ratio. There are lots of handling conditions which affect the physical properties of improved dental stone, and it's well known that the water/powder ratio significantly affect the strength of die stone. If water/power ratio was incorrect, following disadvantages were showed : (1) susceptibility to dimensional change due to abrasion, (2) limited reproduction of fine detail, (3) lack of strength. The maxillary master casts were made of additional silicone impressions(Exaflex, GC America. Inc. USA). Three type IV die stones such as Fuji Rock (GC Europe Intreleuvenlaan, Leuven, Belgium), Velmix(Kerr, Manufacturing company, USA), and Crytal Rock( Maruishi Gypsum Co. Ltd, Japan) were tested. A total of 160 casts were prepared, separated, and tested on the Instron Testing Machine(Model 4201, Co. USA). The obtained results of this study were as follows : 1. Fuji Reck and Velmix less 3ml than the water/power ratio of manufacturer's instruction showed the highest resistance to fracture. According to increasing water/powder ratio, fracture resistance was significantly increased(P<0.05). Crystal Rock showed the highest fracture value when it was mixed with the water/power ratio of manufacturer's instruction. 2. Water/powder ratio of the manufacturer's instructions and less 3ml than that showed lower fracture value of hand mix than that of vacuum mix. Water/powder ratio of more 3ml, 6ml than manufacturer's instructions was not significantly different between hand mix and vacuum mix(p>0.05). 3. Velmix had the highest viscoelastic value among three die materials when it was mixed with the manufacturer's instruction. Viscoelasticity was decreased according to increasing water/powder ratio.

• 농촌계획
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• 제20권4호
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• pp.13-24
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• 2014

The pond wetlands in agricultural landscape are important natural resources that carry out the function of bio-diversity conservation. However, recently, those have been gradually embedded as their utility value were disappeared. And, the assessment methods used for pond wetlands are insufficient. Therefore, this study was conducted to examine the conservation value of pond wetlands by using the modified RAM, and present the improvement of assesment methods. The study sites, a total of 32 pond of 4 types by land use, were selected on the basis of Ramsar Convention. Through the analysis of precedent studies, the weighted 8 functions were adjusted. According to the assessment results, pond wetlands made the largest contribution to Fishery and Herpetile Habitat function. In addition, it also made large contribution to Floral Diversity, Wildlife Habitat, and Water Quality Protection function. On the other hand, it made a small contribution to Aesthetics and Recreation, Runoff Attenuation, Shoreline /Stream Bank Protection, and Flood/Storm Water Storage function due to the characteristics of small-scale pond wetlands. In the assessment of 8 functions, house type showed the worst assessment result, and mountain type showed the best assessment result. It is thought that those are due to land use type in terms of vicinity. 10 items among 52 of the modified RAM showed the same assessment results in all land use types. Accordingly, it is required to be deleted and modified the assessment method. On the other hand, it is required to add age, interference, and water use to the assessment method. It is thought that these results can be utilized for the development and modification of assessment methods focused on pond wetlands in rural area.

• Journal of Animal Science and Technology
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• 제61권5호
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• pp.254-259
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• 2019

The objective of this study was to evaluate the nutritive value of polished rice (PR) vs unpolished rice (UPR) as a potential feedstuff for sheep in order to use as a replacer to corn in sheep diet, and as well as to present the application in the formulation of cattle diet. Six corriedale ewe were randomly assigned to each treatment. UPR and PR were provided as a dietary treatment together with timothy grass as a basal diet in a crossover design for two period with 15-d duration for each period. The ratio of experimental and basal feeds were 33.3% and 66.7%, respectively. The differences in the total digestible nutrient (TDN) contents between sheep and cattle was determined according to the references. The number of data collected sheep and cattle was 9 and 17, respectively. The PR showed higher nutrients digestibility than UPR. Similarly, higher TDN content was observed PR than UPR (p < 0.05). As a result, the replacement of corn in the formulate feed with UPR and PR feed rice could be possible with the ratio of 91.2% and 100.0%, respectively. The result of comparation the TDN contents of UPR and PR in sheep and cattle, the PR has no difference in the nutritive value which suggests the applicability of the results of sheep to cattle. On the other hand, UPR has known to have different nutritive value between sheep and cattle, so caution should be taken when preparing formula feeds for cattle.

• 한국연초학회지
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• 제20권2호
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• pp.139-143
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• 1998

The occurrence and physico-chemical properties of flat leaves found in 1997 curing trial related to the prevention of occurrence of flat leaves at bulk curing of flue-cured tobacco were investigated and compared with those of normal leaves. Cured leaves of NC82 were separated into 4 classes of none, slight, fair and severe symptoms of flat leaf by the percentage of flattened parts to whole leaf area. The flat leaves were mostly found among the leaves of lower stalk position, and it was estimated that growth rate of lower leaves also influenced on the occurrence of flat leaves. In chromatic aberration of cured leaf, flat leaves showed remarkably lower b and L values than in those of normals but there was no difference in a value. On the other hand, in chemical analyses of flat leaf samples, nicotine, total sugar, ether extract and total nitrogen contents were decreased with the degree of flat symptoms. In physical properties, filling capacity of cured leaves was decreased with the degree of flat symptoms comparing with those of normal leaves, while shatter index was showed a reverse tendency, and then within the same leaf, flat parts were decreased in total sugar, ether extract and filling capacity compared with those of normal ones, but remarkably increased in shatter index, and there was no difference in nicotine and total nitrogen contents.

• 유통과학연구
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• 제17권10호
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• pp.73-81
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• 2019

Purpose - The purpose of this study was to examine the effect of the heuristic type of consumers affecting purchase decision making and the intention of shopping value in their relationship to derive mobile social commerce purchase promotion plans. Research design, data, and methodology - A research model was constructed to relate the mediating effect of shopping value between heuristic types and purchase intentions. A total of 233 valid questionnaires were used for analysis for users using mobile social commerce. The statistical program used SPSS 24.0 and AMOS 24.0, and correlation analysis, regression analysis, and 3-step parametric regression analysis were used for the analysis. Results - The results of the analysis showed that representativeness heuristics, availability heuristics, adjustment heuristics, and affect heuristics had a statistically significant effect on the utilitarian value and the hedonic value. On the other hand, affect heuristics among the heuristic types were found to have the greatest influence not only on the utilitarian value but also on the hedonic value. The two types of shopping value were found to be partially mediated between representativeness heuristics and purchase intentions, between adjustment heuristics and purchase intentions, and fully mediated between availability heuristics and purchase intentions, affect heuristics and purchase intentions. Conclusions - These findings suggest that mobile social commerce companies should check in advance how consumer heuristic types affect purchase intentions. In particular, affect heuristics are caused by consumers' emotional mood such as mood or external stimulus being more important to decision making than rational decision making. Therefore, the result of this study suggests that it can be an important factor to secure the competitiveness that the potential customers who access to use mobile social commerce can feel enough fun and enjoyment in the platform provided by the company. It is also worth paying attention to the utilitarian and hedonic values perceived by consumers. This is because the judgment regarding the economic, convenience and important information provided by the mobile social commerce users affects the purchase intention through the trust of the information, past use, and shopping experience displayed on the mobile social commerce platform.

• 복식
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• 제61권4호
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• pp.63-75
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• 2011

The purpose of this study were to investigate influences of perceived value and perceived risk on purchasing behavior for imported apparel from official dealer and unofficial dealer in internet shopping mall. A total of 363 female subjects with ages ranging between 20's and 30's completed the questionnaire. The results of this study were as follows. 1) Imported apparel through official dealer had no influence by impulse buying for convenience and efficiency value, information value, after-purchasing value. On the other hand, imported apparel through unofficial dealer had a negative influence by impulse buying for convenience and efficiency value. 2) Imported apparel through official dealer had a negative influence by impulse buying for function and service risk. But for imported apparel through unofficial dealer, not only function and service risk but also private information risk were influenced by impulse buying. 3) All of imported apparel through official dealer and unofficial dealer had no influence by flow for convenience and efficiency value, information value, after-purchasing value. 4) All of imported apparel through official dealer and unofficial dealer were influenced by flow for function and service risk. That is to say, when consumer find satisfaction about quality of products, whether real thing or not, guarantee of quality, consumer's purchasing behavior will be enhance.

• 지능정보연구
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• 제17권4호
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• pp.193-212
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• 2011

스마트폰의 대중화와 함께 모바일 메신저 서비스는 모바일 시장의 중요한 키워드로 부상하고 있다. 갈수록 경쟁이 심화되고 있는 모바일 메신저 시장에서 고객 충성도 제고는 기업 비즈니스 생존을 위한 열쇠이자, 기업 마케팅 전략의 목표 일 것이다. 이에 본 연구는 모바일 메신저 서비스 수용 후 발생되는 지각된 고객가치, 사용-확산 그리고 충성도 간에 어떠한 영향을 미치는지를 알아보고, 연구 결과를 통해 모바일 메신저 서비스 고객 확보 및 충성도 제고를 위한 시사점을 제공하고자 하는 것이 연구의 주목적이라 할 수 있다. 연구결과, 지각된 가치는 서비스 사용량에 영향을 미친다는 결과가 나타났다. 또한 사용량은 지속적 사용의도와 타인 추천의도에 영향을 미치며, 사용 다양성은 타인 추천의도에 영향을 미치는 것으로 나타났다. 한편, 지각된 가치는 지속적 사용의도와 타인 추천의도에 영향을 미치며, 브랜드 전환의도의 경우 사회적 가치 요인만이 브랜드 전환의도에 영향을 미치는 것으로 나타났다. 연구결과에 따른 시사점으로 서비스 제공자는 모바일 메신저 서비스 사용을 확산시키고 지속적인 사용을 촉진하기 위하여 첫째, 사용자들의 서비스 사용과 연결된 지각된 가치에 대한 인식을 고취 시킬 필요가 있으며, 둘째, 서비스의 충성도에 영향을 미치는 사용-확산 패턴이 다름을 인식하고, 충성도를 제고 할 수 있는 사용자의 사용-확산 전략을 수립 할 필요성이 있다. 마지막으로, 사용자가 경쟁적인 대안에서 충족시킬 수 있는 고객가치 요인이 무엇인지 분석하여 고객 충성도를 높이고 관계를 지속해나갈 수 있는 방법을 모색해야 할 것이다.

• 재활치료과학
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• 제3권2호
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• pp.71-81
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• 2014

목적: 본 연구의 목적은 CPM (Continuous Passive Motion)을 뇌졸중 환자의 손 기능 및 수부 근력 재활에 사용하고 그 영향을 살펴보는데 있다. 연구방법 : 본 연구의 대상자는 뇌졸중으로 인한 편마비 증상을 가진, Brunnstrom 4-6단계에 해당하는 치료후 18개월 이내의 급성기 환자 3명이다 연구방법은 3명의 대상자에 대하여 단일사례 (A-B) 실험설계를 사용하였으며 CPM의 영향을 검사하기 위해 젭슨수지기능, 퍼듀페그보드, 수부근력 세 가지를 측정하였다. CPM 적용기간은 3주였으며, 적용회수는 하루 2회, 매회 20분씩, 총 30회기였다. 연구결과: 수부근력 측정 중 손끝잡기에서 대상자 2명의 값이 변화가 없었다. 그 외의 젭슨수지기능, 퍼듀페그보드, 수부근력 검사에서는 CPM 적용 후의 검사 결과가 향상되었다. 결과의 유효성 검증을 위하여 비모수적 통계방법인 Wilcoxon signed ranks test를 실시한 결과 모든 항목에 대한 P-Value가 0. 05 보다 큰 값이 나와 처치 전 후 값의 차이가 통계적으로는 유의미하지 않다는 결과를 얻었다. 결론: 참여 대상자 수가 적고 프로그램 적용 기간이 짧은 제한점이 있으나, 수부 재활을 위해 실시한 CPM이 연구대상자 전원의 손 기능 및 근력 향상에 영향을 주었다는 것을 확인하였다. 이는 주로 하지 기능과 근력 향상을 위해 사용되는 CPM이 급성기 뇌졸중 환자의 수부 치료에도 유용하게 사용될 수 있음을 보여준다.