• Journal of the Korean Operations Research and Management Science Society
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• v.37 no.3
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• pp.13-21
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• 2012

In this note, a recent work in Won (2011) which investigates properties of the newsvendor model under progressive multiple discounts is revisited and a complete proof is provided for the conjecture on the consistent advantage of progressive multiple discounts over no-discounts in terms of the expected profit. The proof considers the generalized newsvendor model under progressive multiple discounts extended with positive shortage cost and salvage value which have not been considered in the previous newsvendor models under progressive multiple discounts. Without relying on derivatives, we prove that the expected profit under progressive multiple discounts are consistently greater than or equal to the one under no-discounts for every order quantity as far as her multiple discounts do not decrease customer demand, and therefore, the optimal expected profit under progressive multiple discounts is always greater than or equal to the one under no-discounts. As by-products from the proof, some interesting features of the generalized newsvendor model under progressive multiple discounts are revealed.

• Journal of the Korean Regional Science Association
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• v.14 no.2
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• pp.51-64
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• 1998

This paper investigates how the factor inputs of firms are affected by the expectation about land-price increase in the future. We develope a two-factor (land and labor) model, in which expectation about land-price increase plays a key role in determining the "optimal" input level of labor and land. Expecting capital gains from input of the land when land price increases, firms input land up to the point where the marginal productivity of land falls short of the marginal cost of purchasing the land, in order to maximize the "joint-profit". That is, firms have an incentive to use more land than they do when capital gains are not expected. We mean joint-profit by profit in the standard sense plus capital gains. Once the land is input "excessively", the productivity of labor increase and labor is also input more, since land and labor are assumed as complementary in production. This mechanism works in the opposite direction when land price decrease. This paper suggests that land price fluctuation is a major destabilizer of an economy.or destabilizer of an economy.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.4
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• pp.234-239
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• 2003

In recent decades, many countries have introduced competition in the electricity industry. Now, unit commitment becomes not a problem to be solved by a monopoly company but the one to be tackled by each generation company(GENCO). Its aim has been altered from the global cost minimization to the each GENCO's profit maximization. In this paper, the author proposes the scheme of unit commitment of a GENCO to maximize profit considering the uncertainty of market clearing price. The type of the assumed market is a uniform price market. A genetic algorithm is used for the maximization of the profit.

• Journal of Integrative Natural Science
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• v.17 no.2
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• pp.43-51
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• 2024

Jung et al.(2015) suggest the two-phase warranty model, which is a general type of warranty model. Under the two-phase warranty, the warranty period is divided into two intervals, one of which is for renewing replacement warranty, and the other is for minimal repair warranty. And warranty policies play a very important role in product marketing. In this paper, we suggest the optimal warranty policy for free extended two-phase warranty. To determine the optimal warranty period, we adopt the expected profit per unit product. So, the expressions for the total expected cost, the sale price and the expected profit per unit product from the manufacturer's point of view are derived. Also, we discuss the optimal warranty period and the numerical examples are provided to illustrate the proposed the warranty policy.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.5
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• pp.683-689
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• 2017

Objective: The experiments were carried out to measure the effect of multivitamin, acidifier and Azolla on growth performance, profitability and lipid profiles of blood of broiler chickens to produce safe and cost effective broilers. Methods: In experiment 1, 240 day-old Cobb-500 broiler chicks were fed diets; $D_1$ (control), $D_2$ ($D_1$ with 1 mL multivitamin/liter water), $D_3$ ($D_1$ with 1 mL acidifier/liter water), $D_4$ ($D_1$ with 1 mL multivitamin and 2 mL acidifier/liter water) having 3 replications in each, and 20 chicks/replication. In experiment 2, 150 day-old Cobb-500 broiler chicks were fed diets; $T_1$ (control), $T_2$ (5% Azolla in the diet), $T_3$ (7% Azolla in the diet) and $T_4$ ($T_1$ with 1 mL multivitamin and 1 mL acidifier/liter water) having 3 replications in each, and 20 chicks/replication in control, and 10 chicks/replication in the remaining dietary treatment groups for 35 days. Results: In experiment 1, the highest live weight was observed in $D_4$ (p<0.05), however, feed intake was statistically similar between diets (p>0.05). The lowest feed conversion ratio (FCR) (p<0.001) and mortality (p<0.05) were observed in $D_2$ followed by $D_4$, $D_1$, and $D_3$, respectively. There were no significant differences between diets for feed cost and net profit (p>0.05). However, evidently but not significantly, the highest net profit was obtained in $D_2$ followed by $D_4$, $D_1$, and $D_3$, respectively. In experiment 2, the highest live weight (p<0.05) and feed intake (p<0.001) were observed in $T_4$. Mortality (p<0.01), FCR (p<0.01), feed cost (p<0.05) and net profit (p<0.05) were significantly different among diets. Considering net profit, $T_2$ was the best performing dietary group followed by $T_3$, $T_1$, and $T_4$, respectively. The lowest lipid profiles were observed in $D_3$ followed by $D_1$, $D_4$, and $D_2$, respectively (p<0.05). In experiment 2, the lowest total cholesterol, TG, and the highest amount of high density lipoprotein were observed in $T_2$, followed by $T_3$, $T_1$, and $T_4$, respectively (p<0.05). Evidently but not significantly, low density lipoprotein was the highest in $T_2$ followed by $T_3$, $T_4$, and $T_1$, respectively (p>0.05). Conclusion: In conclusion, Azolla and acidifier reduced lipid profiles of broiler chickens. Considering net profit and lipid profiles, 5% Azolla may be the suitable dietary group for producing safe and profitable broilers. However, more studies are needed to confirm this study prior to suggesting using Azolla in the poultry industry.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1452-1458
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• 2004

An experiment was conducted to examine the effects of sex and market weight on performance, carcass characteristics and pork quality. A total of 224 crossbred pigs (initially 26.64 kg BW) were allotted in a $2{\times}4$ factorial arrangement in a randomized complete block (RCB) design. The variables were sex (gilts and barrows) and different market weights (100, 110, 120 and 130 kg). Average daily gain (ADG) and average daily feed intake (ADFI) were significantly higher (p<0.01) in barrows than gilts, ADFI and feed conversion ratio (FCR) increased as body weight increased (p<0.05). Gender differences were observed in carcass characteristics. Backfat thickness and drip loss were greater in barrows (p<0.01), while loin eye area (p<0.01), flavor score (p<0.05) and lean content (p<0.001) were higher in gilts. Carcass grade and water holding capacity were the highest in 110 kg market weight pigs. The 100 kg arket weight pigs showed lower juiciness, tenderness, shear forces and total palatability than the other market weights (p<0.01). Hunter values (L*, a* and b*) were increased as market weight increased (p<0.05). Hunter a* value was greater in gilts (p<0.01) but L* value and b* value were not affected by sex of pigs. Net profit [(carcass weight${\times}$price by carcass grade)-(total feed cost+cost of purchased pig)] was higher in gilts than barrows (p<0.01), and was higher (p<0.05) in the pigs marketed at 110 and 120 kg market weight compared with 100 kg market weight. These results demonstrated that gilts showed higher carcass characteristics, pork quality, feed cost per kg body weight gain and net profit compared with barrows. Moreover, 110 or 120 kg body weight would be the recommended market weight based on pork quality and net profit for swine producers.

• Journal of Animal Environmental Science
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• v.3 no.1
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• pp.49-56
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• 1997

Most of Korean broiler farms are constructed with vinyl houses. Such types of broiler farms might be cheaper in terms of cost, but poor in terms of environment condition. According to enlargement of broiler farm size, high value production systems or automatic facilities are introduced in this field. However, investment may not always guarantee the profit of the management. Therefore, it is necessary to undertake the investment analysis before decision making for the investment. Under the assumption that 870 Pyoung(≒$3.3㎡) of a broiler farm within 1,740 Pyoung(≒3.3㎡) of land is built with the producing capacity of 50,000 heads of chicken in a time. The total investment is calculated to be 600 million won(1,000 won≒$1.1), and out of them 58.1% is provided by the owner, 31.6% from the government loan, 5.8% from government subsidy, and 5.3% from other agencies or banks. The expected profit of the broiler farm is 64.6 million won(1,000 won≒$1.1) per year. The IRR calculated is 0.0808 which means that the rate to profit of this project would be 8.1%. This also means that for this investment the interest rate of the capital provided should be less than 8.1% per year. Considering that the current opportunity cost of the own capital is 8.5% this project is not so attractive for those who is going to build broiler farms mainly with their own capital. In other words this project would not be profitable, unless the average interest rate of the loans provided for this project is less than 8.1% per year.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.64 no.4
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• pp.273-276
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• 2015

In this paper, ESS capacity installed in industrial customer is calculated using economic analysis. To do this, electric charge for industrial customer is analyzed and power management system(PMS) of ESS is selected. Reduction of kW cost and kWh cost are set to 'benefit' according to operation of ESS. Also, installation cost and maintenance cost of ESS are set to 'cost'. Proper ESS capacity is determined as a result of benefit-to-cost(B/C) analysis according to the variation of ESS installation cost. In case study, B/C is analyzed for the specific industrial customer and minimum capacity of ESS to make a profit are proposed for the customer.

• The Journal of Fisheries Business Administration
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• v.7 no.1
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• pp.27-41
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• 1976

The results analyzed of the actual state of the stow net fisheries based on the cost expended in 1975 areas follows; The total cost of this fisheries will be 1, 672, 238 won; the production cost, 1, 588, 060 won (95%) ; the material cost in proportion to total cost (100%)408, 480won (24.4%);the labour cost, 1, 006, 480 won (60.2%) ; the expenses, 173, 100won(10.4%)and the commission and the interest payment, 84, 178won(5%). As above the commission and the interest payment doesn't need to be paid much, but only production cost should be paid in case of small scale inshore fisheries. The cost per unit of caches (per Kg) becomes 12 won, the ratio cost of sales (83.4%), the ratio of profit, 16.%. According to the adove, in case of the powered vessel; it shows a tendency of spending too much expenses owing to excessive payment of oil. And in case of nonpowered vessels, it shows a tendency of spending less expenses but still get much gains, due to the fact that the commission and the interest payment are less, and none is paid for fuel procurement.

• Journal of Digital Convergence
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• v.14 no.5
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• pp.39-46
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• 2016

The history of Social service is above 10 years. Owing to corresponding to the user's needs social services sector is expanding. And, to deal with them, the social delivery systems has been changed. Traditional social welfare delivery system is provided by public facilities and private facilities. On the other hand, Social Services is made up of the traditional social welfare delivery system and new delivery system which is composed of profit organizations and non-profit organizations. Considering this, Study attempted to compare the performance evaluation of supply type-profit and non-profit social service organizations. Performance evaluation method was applied to net income, except for expenditure in total revenue. Net income difference between profit organization non-profit organization was assessed by T-test. We conclude that the two population means are different at the 0.05 significance level. Looking in detail, the non-profit organizations were found to be higher than the non-profit organizations, labor costs, operating costs, facility cost and consumable costs, but part of the business expense costs, the non-profit organizations was higher than the profit organizations.