• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.1
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• pp.13-20
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• 2022

Aircraft weight is an important factor affecting performance and fuel efficiency. In the conceptual design stage of the aircraft, the process of balancing cost and weight is performed using empirical formulas such as fuel consumption cost per weight in estimating element weight. In addition, when an airline operates an aircraft, it promotes fuel efficiency improvement, fuel saving and carbon reduction through weight management activities. The relationship between changes in aircraft weight and changes in fuel consumption is called the cost of weight, and the cost of weight is used to evaluate the effect of adding or reducing weight to an aircraft on fuel consumption. In this study, the problems of the existing cost of weight calculation method are identified, and a new cost of weight calculation method is introduced to solve the problem. Using Breguet's Range Formula and actual flight data of the A350-900 aircraft, two weight costs are calculated based on take-off weight and landing weight. In conclusion, it was suggested that it is reasonable to use the cost of weight based on the take-off weight and the landing weight for other purposes. In particular, the cost of weight based on the landing weight can be used as an empirical formula for estimating element weight and optimizing cost and weight in the conceptual design stage of similar aircraft.

• Korean Journal of Poultry Science
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• v.10 no.2
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• pp.123-128
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• 1983

Fifty of one day-old chicks of silky fowl were hatched at Dept. of Animal Science, Gyeongsang National University and fifty of one day-old chicks of quails were hatched at Gim Hae, Gyung Nam. This experiment was investigated at 24 hours after incubation. Twee items investigated in this experiment were the live weights, the weights of head, eye-ball, brain, heart, liver, lung, kidney, stomach, small intestine, large intestine, and yolk sac. The results obtained are summarized as follows; 1, Average weights of body, head, eye-ball brain, heart, liver, lung, kidney, stomach, small intestine, large intesine and yolk sac of the quail chicks and standard errors were 6.54${\pm}$0.02g, 1.38${\pm}$0.l3g, 0.29${\pm}$0.004g, 0.24${\pm}$0.006g, 0.08${\pm}$0.002g, 0.21${\pm}$0.005g, 0.06${\pm}$0.002g, 0.05${\pm}$0. 002g, 0.46${\pm}$0.010g, 0.24${\pm}$0.008g, 0.10${\pm}$0.004g, and 0.28${\pm}$0.0l6g, respectively. 2. Average weights of body, head, eye-ball, brain, heart, liver, lung, kidney, stomach, small intestine, large intestine, and yolk sac of the silky fowl chicks and standard errors were 26.60${\pm}$0.491g, 4.28${\pm}$0.071g, 0.64${\pm}$0.039g, 0.55${\pm}$0.025g, 0.21${\pm}$0.0l2g, 0.77${\pm}$0.030g, 0.13${\pm}$0.006g, 0.08${\pm}$0.006g, 1,53${\pm}$0.076g 0.73${\pm}$0.036g, 0.42${\pm}$0.031g, and 2.65${\pm}$0.297g, respectively. 3. The relative ratios of the organ weight versus body weight in guails were compared with those of the commercial chicks (Hibro, Hubbard, and Hisex) and silky fowls. It was noted that the relative weights of the brain and eye ball with respect to body weight were larger in case of quails (Table 3). The weights of heart, liver, lung, kidney, stomach and small intestine in silky fowl were smaller than those of commercial chicks and quail chicks. Other items were similar in weight to commercial chicks ana quail chicks.

• Journal of the Society of Naval Architects of Korea
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• v.33 no.4
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• pp.97-105
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• 1996

For the minimum weight design of ship structures it is desirable that tank arrangement is predetermined to obtain the minimum weight and then structural arrangement and scanting of each murder is determined to obtain the minimum weight within the given tank arrangement. To carry out the tank arrangement to give minimum weight a minimum weight design program which covers whole ship structures is developed by the combination of minimum weight design program of longitudinal members by classification rules and minimum weight design program of transverse members by generalized slope deflection method which were developed by the authors. The hullweight is estimated by summation of the weight of cargo hold part and the weight except cargo hold part which can be estimated by the empirical formula. In this study, the variation of hullweight is shown with the number of tank, the number of web and the location of longitudinal bulkhead. For the application of actual design alternative designs of tank arrangement which satisfy MARPOL regulation are determined. And several minimum weight designs of whole ship structures are carried out to obtain the tank arrangement which gives minimum weight and then the hullweight is compared with that of existing ship.

• Proceedings of the ESK Conference
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• 1994.04a
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• pp.52-63
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• 1994

산업현장에서 산업재해의 주요한 요인이 되는 중량물 수운반 활동시 작업자가 안전 하게 작업을 행하면서도 최적허용중량을 결정하기위한 연구는 주어진 작업조건하에 서 인양되는 최대중량을 결정하기 위한 기준으로서 척추에 가해지는 압력을 이용하는 생체역학적 접근법, 주어진 작업조건하에서 인양되는 최대중량을 결정하기 위한 기준 으로서 에너지 소모량을 이용하는 생리학적 접근법, 주어진 작업조건하에서사람이 인 양할 수 있는 최대중량을 결정하는 기준으로서 피실험자에의해서 인지되는 힘든 정도를 이용하는 정신물리학적 접근법 등으로수행하여 왔다.

• Food Science of Animal Resources
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• v.21 no.4
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• pp.337-343
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• 2001

Changes of Physicochemical compositions in domestic broiler chickens of different marketing standard range from 5ho (Korean traditional weight unite for chicken) to 16ho were assessed. The moisture contents of chicken breast were 74.00 ∼ 76.15% and there were no significant trend with weight difference. The chicken breasts of the light weight range(5ho∼8ho) contained high fat contents of 2.35∼2.78%. The chicken breasts of the heavy weight range(12ho∼16ho) contained low fat contents of 0.47 ∼0.66%. The chicken breasts of the heavy weight range had more protein contents than those of the light weight range. The chicken breast of the light weight range showed low Warner Braztler shear force (WBS) values when compared to those taken from chicken of the heavy weight range. However. there was no significant differences in water ho1ding capacity (WHC ) and cooking loss(p>0.05). In meat color the L* values (lightness) were 61.83∼71.33 and there were no significant differences for samples in different weight range except 5ho and 13ho. The b* valuers (yellowness) were 1.73 ∼6.79 and the values decreased with increasing chicken weight. In mineral composition. calcium and iron contents were decreased with increasing chicken weight. Phosphate, potassium and magnesium contents increased as weight ranges increased. The thigh meat separated from 11ho to 16ho had a similar tendency. In chemical composition(%). WBS, WBC. cooking loss, meat colors and mineral contents, compacted to breast in the same weight ranges. The results from this study would provide a basic information for establishment of marketing standard of chicken.

• Journal of Korean Society of Forest Science
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• v.111 no.4
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• pp.630-643
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• 2022

This study was conducted to derive the fresh weight and dry weight estimation formulas of Pinus densiflora and prepare a weight table using them. Aone-variable formula using only the diameter at breast height (DBH) and a two-variable formula using DBH and height were used to calculate the fresh and dry weight. Each equation was verified using statistics, such as fit index, standard error, and residuals. Theoptimal equation was evaluated for applicability by calculating the weight as a coefficient derived from a statistical verification. W = bD+cD² was selected for the one-variable equation, while W = aD^bH^c was selected for the two-variable equation. The fit index of the former was 0.87-0.92, while that of the latter was 0.94-0.98, both of which showed a good fit. A new weight table was prepared using the optimal estimation formula, and it was compared and analyzed with a previous weight table. Analysis results showed that Gangwon pine had higher values in the previous weight table, while pines in the central region had higher values in the newly created weight table.

• Journal of Wetlands Research
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• v.7 no.2
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• pp.145-158
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• 2005

To clarify the growth of Phragmites communis along the distance from the land, and investigate the effects by cutting the aboveground part, the height and dry weight of this species were surveyed from 2000 to 2001 on natural stands at tidal-flat of Hogog-ri, Jugog-myeon, Whaseong-city, Gyeonggi Province. At the stand near the rice paddy, mean density, mean height, dry weight per plant and dry weight per unit area of P. communis were $122.67plants/m^2$, 100.36 cm, 4.241 g, and $537.574/m^2$, respectively. The sizes of P. communis conspicuously increased from seaside to land side. At the stand isolated from the land, these properties were $102.30plants/m^2$ (in density), 43.894 cm (in height), 0.779 g/plant and $73.495g/m^2$, respectively, and the sizes of P. communis at the land side were relatively similar to those at sea side. The cutting of aboveground part resulted to the decrease of density and dry weight per unit area in next year, but did not influence on the height and weight per plant of P. communis.

• Journal of Navigation and Port Research
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• v.43 no.1
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• pp.16-22
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• 2019

This study proposed estimation methods for weight and center of gravity of small fishing vessels. Weights loaded on small fishing vessels were divided into fixed weights such as crew, fishing gear, and variable weights such as fuel, fresh water, provision, bait, and fish. Based on statistical analyses with weight data of several small fishing vessels, weight, longitudinal center of gravity (LCG), vertical center of gravity (KG) of each item were represented as linear functions of vessel gross tonnage. In addition, weighting factors of variable weights were added on estimation formulas in accordance with vessel loading conditions, e.g. full load departure condition. Estimation methods were verified using actual small fishing vessel data.

• Proceedings of the Korean Society of Computer Information Conference
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• 2013.07a
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• pp.149-151
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• 2013

본 연구의 목적은 휴대용 보병무기체계의 배낭 설계를 위하여 인체공학적인 물자취급 중량을 검토하는데 있다. 제품설계시 인체공학적 설계 가이드라인과 운용현황을 조사분석하여 효율적인 운용성능을 위한 기초자료를 제공하고자 한다. 기존의 설계 가이드라인을 분석한 결과, 병사의 인체사이즈 측면에서는 5%tile의 경우 -091kg으로 여유중량이 부족하지만, 95%tile에서는 34.17kg까지 여유중량이 발생하는 것으로 판단된다. 이러한 연구결과는 물자취급시 편하고, 효율적인 운용성능을 창출하기 위해서 휴대중량과 이동거리에 따라 여유중량을 관리해야 할 것으로 판단된다.

• The Korean Journal of Rheology
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• v.3 no.1
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• pp.38-46
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• 1991

저분자량(분자량: 1.04$\times$104 g/mole)과 고분자량(3.84$\times$106) 폴리스타이렌 브렌드를 제조하고 무접촉 무마찰을 이용한 비틀림 크립장치를 사용하여 점도, 크립 캄플라이언스들 을 측정하고 또 지연 스펙트라도 계산해 내었다. 고분자량의 농도는 0, 2, 10, 20, 50, 70, 100 중량 퍼센트였다. 점도는 블렌드의 중량평균 분자량이 임계분자량이상이면 중량평균의 3.5승에 비례했다. 중량평균 분자량>임계분자량 인블렌드의 경우 정상상태 회복 캄플라이언 스는 중량평균의 3.5승에 비례했다. 중량평균 분자량>임계분자량 인 블렌드의 경우 정상상 태 회복 캄플라이언스는 중량평균의 -2.3승에 비례했다. 지연스펙트라를 검토한 결과 폴리 스타이렌의 임계분자량은 38000 g/mole 쯤으로 추정되었다.