• 제목/요약/키워드: CSS

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Feeding Value of Sugarcane Stalk for Cattle

  • Kawashima, T.;Sumamal, W.;Pholsen, P.;Chaithiang, R.;Boonpakdee, W.;Kurihara, M.;Shibata, M.
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권1호
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    • pp.55-60
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    • 2002
  • A metabolism trial with four castrated male Brahman cattle, average body weight 320 kg, was conducted in order to determine the nutritive value of chopped sugarcane stalk (CSS) for the establishment of feeding strategy in the dry season in Northeast Thailand. Animals were subjected to the following four dietary treatments: Treatment 1; 100% of CSS, Treatment 2; 70% of CSS and 30% of commercial complete feed (TMR), Treatment 3; 40% of CSS and 60% of TMR, and Treatment 4; 100% of TMR. The average CP, ether extracts, nitrogen free extracts, crude fiber and ash contents of CSS were 2.0, 0.9, 79.0, 16.1 and 2.2%, respectively. Although the amount of feed given was approximately at maintenance level, animals in treatments 1 and 2 refused a part of feed. The metabolism trial revealed that total digestible nutrient and metabolizable energy contents of CSS were 61.5% and 9.04 MJ/kgDM, respectively, when it was properly supplemented with protein sources. Nutritive value of CSS was lowered when animals were given CSS solely. This was due to the large loss of energy into urine and methane. Voluntary intake of CSS in cattle was not enough to satisfy energy requirement for maintenance. The CSS can be used as a roughage for feeding cattle in the dry season with proper supplementation of protein and energy.

국내 연안 카페리 차량 고박 장치 안전성에 관한 연구: 제2부 가속도 예측 방법에 따른 고박 안전도 비교 연구 (Study on Structural Safety of Car Securing Equipment of Coastal Carferry: Part II Assessment of Lashing Safety according to Acceleration Prediction Approaches)

  • 정준모;조희상;이경훈;이영우
    • 한국해양공학회지
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    • 제30권6호
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    • pp.451-457
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    • 2016
  • For a carferry with a displacement of 1,633 tonf, a seakeeping analysis-based direct load approach (DLA) was used in Part I of these series, where the final deliverable was the long-term probabilistic acceleration components. In Part II of these series, the tangential acceleration components are explained based on two approaches: a standard called the IMO CSS code and simple formulas with the probable maximum roll and pitch rotations. The subsequent tangential acceleration-induced external force components are also introduced for these two approaches. The lashing strength components were selected from the IMO CSS code. It was assumed that two different vehicles (a car and a truck) were stowed at the most distant locations on the main deck to assume the largest tangential acceleration components and were secured with four steel wires with longitudinal and transverse lashing angles of $45^{\circ}$. Four cases were considered, with different methods for predicting the acceleration components and different tools for the external loads and lashing strengths involved: cases Rule-LS (rule-based maximum probable roll and pitch angles for predicting the acceleration components in conjunction with LashingSafety), DLA-LS (seakeeping-based long-term acceleration components with LashingSafety), CSS-LC (IMO CSS code-based acceleration components using LashCon), and CSS-LS (IMO CSS code-based acceleration components using LashingSafety). In terms of the acceleration and external force components, the CSS-LC and CSS-LS results are more than two times the results of Rule-LS. Thus, when the external forces and lashing strengths are evaluated using CSS-LC and CSS-LS, the truck needs more lashing wires, while Rule-LS and DLA-LS predict that the present lashing configuration is on the safe side.

CSS기반 위치인식 시스템 구현에 관한 연구 (The Design and Implementation of a CSS based Location Aware System)

  • 주준형;김현욱;양성현
    • 한국정보통신학회논문지
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    • 제16권7호
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    • pp.1549-1558
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    • 2012
  • 위치 인식 시스템은 물류, 의료, 홈 네트워크, 군사, 교통 시스템 등 다양한 분야에서 활용된다. 본 논문에서는 무선 RF만으로 정밀한 위치 인식이 가능한 IEEE802.15.4a의 CSS(Chirp Spread Spectrum)방식을 기반으로 다양한 환경에서 사용할 수 있는 위치인식 시스템을 설계하였다. 실험 결과 20m의 반경을 가지는 공간에서 0.5m 미만의 오차범위를 가지는 위치 인식 시스템을 구현하였다.

오버랩 기반 CSS 시스템 설계를 위한 닫힌꼴 비트 오류율 표현 (A Closed-Form BER Expression for Overlap-Based CSS System Design)

  • 윤태웅;이영윤;이명수;송익호;윤석호
    • 한국통신학회논문지
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    • 제34권4C호
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    • pp.469-475
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    • 2009
  • Chirp 확산 대역에서 (chirp spread spectrum: CSS) 데이터 전송량을 증가시키기 위해 사용되는 오버랩 기법은 인접 심벌 간 간섭을 (intersymbol interference: ISI) 유발하여 심각한 비트 오류율 (bit error rate: BER) 성능 저하를 초래한다. 따라서 효과적으로 오버랩 기법을 사용하기 위해서는 요구되는 BER 성능 기준에 따라 적절한 횟수로 오버랩을 실시하여야 한다. 본 논문에서는 근사화 된 가우시안 Q 함수를 바탕으로 오버랩 횟수를 매개변수로 가지는 오버랩 기법이 적용된 CSS 시스템의 닫힌꼴 BER 성능 수식을 유도한다. 유도한 닫힌꼴 BER 성능 수식의 정확성은 모의실험 결과와의 비교를 통하여 검증한다.

오버랩 기반 DM-BPSK CSS 시스템에서 오버랩 횟수에 따른 심볼 간 간섭 분석 (Analysis of Intersymbol Interference due to Overlap m Overlap-Based DM-BPSK CSS Systems)

  • 김준환;이영포;송익호;윤석호
    • 한국통신학회논문지
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    • 제36권2C호
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    • pp.99-104
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    • 2011
  • 처프 확산 대역 (chirp spread spectrum: CSS) 기술은 데이터 신호를 처프 신호를 통하여 최소 필요 대역보다 더 넓은 주파수 대역으로 확산시켜 전송하는 기술로서 오버랩 기법을 사용하여 데이터 전송률을 늘릴 수 있다. 그러나 데이터의 신뢰성 있는 전송을 위해서는 오버랩으로 인해 발생하는 심볼 간 간섭에 (intersymbol interference: ISI) 대한 분석이 필수적이다. 본 논문에서는 오버랩 기반 direct modulation binary phase shift keying CSS 시스템에서 오버랩 횟수와 ISI의 상관관계를 수학적으로 분석하였다. 구체적으로는 몇몇 특정 오버랩 횟수에 대해서는 오버랩으로 인한 ISI가 나타나지 않으며, 오버랩 횟수의 변화에 따라 오버랩으로 인한 ISI가 진동하거나 단조 증가함을 보였고, 모의실험 결과와 분석한 내용이 일치하는 것을 확인하였다.

준법몰입과 준법지원시스템 사용의도: 지각된 유용성 및 감시우려를 중심으로 (Compliance Commitment and Compliance Support System: Focused on the Perceived Usefulness and Surveillance Concerns)

  • 이성진;김상수
    • 한국정보시스템학회지:정보시스템연구
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    • 제27권4호
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    • pp.97-114
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    • 2018
  • Purpose Compliance support system (CSS) aims to support employees' voluntary compliance activities, however, it requires a different approach from the acceptance of other general information systems. In other words, the user's concern that his/her compliance activities recorded in the system are monitored may hinder the active use of the system. In this regard, we set up a research model to investigate the factors that affect the intention to use CSS, by including perceived usefulness, compliance commitment, and surveillance concern. Design/methodology/approach A questionnaire survey was conducted for the employees of a domestic oil-company, who operates their own CSS. Based on the 865 data collected, a structural model analysis using PLS was conducted. As a result, all four hypotheses were accepted. It was found that perceived usefulness of CSS has a positive effect on the intention to use CSS. Compliance commitment has a positive effect both on perceived usefulness and intention to use CSS. In contrast, surveillance concern of one's non-compliance recorded in the CSS was shown to have a negative effect on the relationship between compliance commitment and perceived usefulness. Findings This study has academic implications in that it extends the viewpoint of the existing technology acceptance mechanism by examining the two aspects, i.e., compliance commitment and surveillance concern. This study may also provide practical directions to strengthen the use of the active compliance support system by the employees.

감정노동과 직무소진의 관계에서 지각된 고객관련 스트레스요인의 매개효과 (The Mediating Role of Perceived Customer-related Social Stressor on the Relation between Emotional Labor and Burnout)

  • 허창구
    • 한국산학기술학회논문지
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    • 제15권6호
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    • pp.3524-3533
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    • 2014
  • 본 연구는 서비스직 종사자의 두 가지 감정노동전략(표면행동, 내면행동)이 직무소진 및 지각된 고객관련 스트레스요인(CSS)에 미치는 상이한 영향과 그러한 영향 과정에서 지각된 CSS의 매개역할을 검증하고자 진행되었다. 대표적인 감정노동 직무라 할 수 있는 호텔서비스직 종사자를 대상으로 자기보고식 설문조사를 실시하였으며 568명의 자료를 분석하였다. 분석결과에서 표면행동은 지각된 CSS와 직무소진을 증가시키고(H1지지), 표면행동과 직무소진의 관계에서 지각된 CSS가 매개역할을 하는 것으로 나타났다(H3지지). 한편, 내면행동은 직무소진을 감소시켰으나 지각된 CSS에는 영향을 미치지 않는 것으로 나타났으며, 그로인해 내면행동과 직무소진의 관계에서 지각된 CSS의 매개역할 또한 지지되지 않았다(H2부분지지, H4기각). 결과적으로, 지각된 CSS와 직무소진을 모두 증가시키는 표면행동과 달리 내면행동의 경우 지각된 CSS를 증가시키지 않으면서 동시에 직무소진을 감소시키는 것으로 나타나 두 가지 감정노동 전략에 대한 상이한 접근의 필요성을 확인하였다. 마지막으로 연구의 시사점 및 제한점을 논의하였다.

Corn stover usage and farm profit for sustainable dairy farming in China

  • He, Yuan;Cone, John W.;Hendriks, Wouter H.;Dijkstra, Jan
    • Animal Bioscience
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    • 제34권1호
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    • pp.36-47
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    • 2021
  • Objective: This study determined the optimal ratio of whole plant corn silage (WPCS) to corn stover (stems+leaves) silage (CSS) (WPCS:CSS) to reach the greatest profit of dairy farmers and evaluated its consequences with corn available for other purposes, enteric methane production and milk nitrogen efficiency (MNE) at varying milk production levels. Methods: An optimization model was developed. Chemical composition, rumen undegradable protein and metabolizable energy (ME) of WPCS and CSS from 4 cultivars were determined to provide data for the model. Results: At production levels of 0, 10, 20, and 30 kg milk/cow/d, the WPCS:CSS to maximize the profit of dairy farmers was 16:84, 22:78, 44:56, and 88:12, respectively, and the land area needed to grow corn plants was 4.5, 31.4, 33.4, and 30.3 ha, respectively. The amount of corn available (ton DM/ha/yr) for other purposes saved from this land area decreased with higher producing cows. However, compared with high producing cows (30 kg/d milk), more low producing cows (10 kg/d milk) and more land area to grow corn and soybeans was needed to produce the same total amount of milk. Extra land is available to grow corn for a higher milk production, leading to more corn available for other purposes. Increasing ME content of CSS decreased the land area needed, increased the profit of dairy farms and provided more corn available for other purposes. At the optimal WPCS:CSS, MNE and enteric methane production was greater, but methane production per kg milk was lower, for high producing cows. Conclusion: The WPCS:CSS to maximize the profit for dairy farms increases with decreased milk production levels. At a fixed total amount of milk being produced, high producing cows increase corn available for other purposes. At the optimal WPCS:CSS, methane emission intensity is smaller and MNE is greater for high producing cows.

IEEE 802.15.4a CSS PHY를 이용한 환경기반 거리측정오차 보정 기법 (Environment-Based Ranging Error Correction Technique Using IEEE 802.15.4a CSS PHY)

  • 남민석;박영균;남영진;이동하;강진규;이상철
    • 대한임베디드공학회논문지
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    • 제4권4호
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    • pp.148-155
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    • 2009
  • Precise localization heavily relies on the accuracy of its underlying ranging technique. It has been known that the Chirp Spread Spectrum (CSS) defined in the IEEE 802.15.4a provides more dependable ranging accuracy than the Received Signal Strength Indicator (RSSI) in the IEEE 802.15.4. This paper examines the accuracy of the CSS-based ranging technique in the indoor/outdoor environments and discovers its consistent inaccuracy in different environments. Next, it proposes an error-correction architecture for the CSS-based ranging technique that exploits the per-environment consistent inaccuracy information and user visiting patterns (represented by weights for each environment).

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Evaluation of Tensile Properties of Cast Stainless Steel Using Ball Indentation Test

  • Kim Jin Weon
    • Nuclear Engineering and Technology
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    • 제36권3호
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    • pp.237-247
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    • 2004
  • To investigate the applicability of automated ball indentation (ABI) tests in the evaluation of the tensile properties of cast stainless steel (CSS), ABI tests were performed on four types of unaged CSS and on 316 stainless steel, all of which had a different microstructure and strength. The reliability of ABI test data was analyzed by evaluating the data scattering of the ABI test and by comparing tensile properties obtained from the ABI test and the tensile test. The results show that the degree of scattering of the ABI test data is reasonably acceptable in comparison with that of standard tensile data, when two points data that exhibit out-of-trend are excluded from five to seven points data tested on a specimen. In addition, the scattering decreases slightly as the content of ${\delta}-ferrite$ in CSS increases. Moreover, the ABI test can directly measure the flow parameters of CSS with error bounds of about ${\pm}10\%$ for the ultimate tensile stress and the strength coefficient, and about ${\pm}15\%$ for the yield stress and the strain hardening exponent. The accuracy of the ABI test data is independent of the amount of ${\delta}-ferrite$ in the CSS.