• 한국건축시공학회지
• /
• 제3권3호
• /
• pp.73-81
• /
• 2003

In this paper, salt damage resistance of high durable concrete was tested. High durable concrete was made by using low water cement ratio, chemical admixture called super-durable admixture and mineral admixtures such as fly-ash, ground granulated blast-furnace slag, silica fume. Two kinds of salt damage resistance test were carried out. One method is chloride ion penetration test(ASTM C1202), and the other one is depth of chloride penetration test in saline solution. Test results were as followers: 1) The depth of chloride ion penetration increased exponentially as water cement ratio was increased and time passed. 2) Super-durable admixture had little effect on the improvement of salt damage resistance of concrete. 3) Silica fume and ground granulated blast-furnace slag were effective on salt damage resistance because of pozzolanic reaction, but fly-ash had a little effect.

• Asia Marketing Journal
• /
• 제20권2호
• /
• pp.29-40
• /
• 2018

Recent research reported that perception of future time is non-linearly scaled. That is, as objective time gets longer, subjective perception of the objective time does not grow proportionally. The non-linear time perception implies that the same future time feels shorter when it starts in the future than when it starts immediately. The authors call this as a future contraction effect. The current research tests two important implications of the effect regarding consumers' intertemporal preference for durable goods. First, consumers who contract future more will be more impatient for durable goods compared to those who contract less because the former would feel to use the same durable goods longer when it is purchased immediately. Second, consumers' impatience will be alleviated when their tendency to contract future is reduced. The authors find support for these predictions through two studies. Taken together, the current research demonstrates a property of time perception that has important ramifications for understanding consumers' intertemporal preference for durable goods.

• KDI Journal of Economic Policy
• /
• 제27권2호
• /
• pp.123-154
• /
• 2005

본 논문은 우리나라 가계의 내구재 소비결정에 관한 실증분석이다. 기존의 연구에 의하면 표준적인 항상소득가설은 비내구재 소비에 대해서는 비교적 높은 설명력을 나타내지만 내구재 소비에 대해서는 설명력이 거의 없는 것으로 나타난다. 본 연구에서는 이러한 항상소득가설의 대안으로서 조정비용의 존재를 허용하는 (S, s)모형을 고려한다. (S, s)모형에 의하면 내구재 소비는 조정비용 때문에 매 순간 최적 수준을 유지하지는 못하지만, 일단 조정이 이루어지는 경우에는 최적 수준을 달성할 것으로 예상된다. 본 논문은 (S, s)모형의 이러한 예측을 검증하기 위하여 한국가구 패널조사자료에 나타난 각 가계의 내구재 소비와 비내구재 소비의 관계 및 내구재 소비의 기간 간 변화를 살펴본다. 분석결과에 의하면 표준적인 항상소득가설은 기각되는 반면 (S, s)모형은 대체로 자료와 일치하는 것으로 나타난다.

• 산업경영시스템학회지
• /
• 제43권3호
• /
• pp.21-28
• /
• 2020

Aftermarket refers to a market in which a company sells complementary goods, replacements of parts, and upgrade or maintenance services to consumers after selling them main durable goods. Intuitively, consumers who purchase main durable goods become major potential customers in subsequent aftermarket. Thus the existence of the aftermarket has a significant impact on pricing of the main durable goods as well as the aftermarket products. In this study, we analyze the effect of aftermarket on the pricing strategy for a company selling both main durable goods and aftermarket products. To do this we first divided the market into markets where the aftermarket products are indispensable and optional. Based on the proposed market types, the profit maximizing solutions are derived using two-period model, and the impacts of consumers' undervaluation of aftermarket product prices on pricing strategy are analyzed. The results can be summarized as follows : (1) Regardless of the market type, the total profits were found to be inversely proportional to the consumer's awareness accuracy of product prices in the aftermarket. This is in line with marketing efforts that sales companies have made intuitively to make consumers underestimate the cost of the aftermarket. (2) If aftermarket product is indispensable, only revenue from the aftermarket is sought. On the other hand, if aftermarket product is optional, revenue from the main durable good as well as the aftermarket product will be sought simultaneously. (3) Moreover, when aftermarket product is optional, the lower the awareness accuracy of consumers, the higher the price and profit of the main durable goods, while the lower the price and profit of the aftermarket products. This is contrary to the intuition that the lower the consumer's valuation of the costs of aftermarket, the more advantageous it would be to rely on aftermarket products rather than on main durable goods.

• 한국의류학회지
• /
• 제20권5호
• /
• pp.792-800
• /
• 1996

The shape retention finishing provides a fabric for easiness of no-ironing after laundering. In spite of the obvious importance of the new finishing treatment, few systematic studies have been performed on the handle of the fabrics finished by the durable press process. The purpose of this research is to investigate the relationships among the mechanical properties, durable press conditions, primary hand values and the total hand value of the fabrics finished by shape retention process. In this experiment, durable press grade of unfinished fabrics decreased below 2.5, but those of finished fabrics maintained above 4, but the mechanical properties of finished fabrics did not change significantly after laundering. In finished fabrics, D.P. value were correlated with mechanical properties, but had little effects with H.V. and T.H.V. Since the evaluation of the effect of durable press process was done with the naked eyes and standard sample, we could not know exactly change o( mechanical properties, but trace the change of mechanical properties which gave influences on the durable press effects by using KES-FB System.

• 식물병연구
• /
• 제21권1호
• /
• pp.20-23
• /
• 2015

A sequential planting method was developed to screen rice plants with durable resistance against rice blast in a short time, and applied for several years in Korean rice breeding program. In this study, we showed the advantages of a sequential planting method compared to other pathogenicity tests. The correlation analysis among three pathogenicity tests and other factors demonstrated that durable resistance depended on the average of diseased leaf area and the number of compatible pathogens. Significant correlations were found in the nursery test but not in the field test result. In addition, we traced changes in the pathogen population during sequential planting stages through re-isolation of the pathogen. The portion of compatible pathogens was increased during sequential planting. Through this study, we provide an effective sequential planting method and direction of durable resistance in a breeding program.

• 한국응용과학기술학회지
• /
• 제19권4호
• /
• pp.291-296
• /
• 2002

Fatty polyamide that gives softness, lubrication and bulky property and alkyl imidazoline that gives durable softness and antistatic property were synthesized. then, an O/W-type durable softener (DSN) was prepared by the emulsion of the synthesized fatty polyamide and alkyl imidazoline. Emulsion stability of the DSN was good, and the mixed HLB value was 11.2. From the measurement of softness, lubrication, antistatic property, bending resistance, and color fastness, it was proved that the prepared DSN was a good durable softener for nylon.

• Computers and Concrete
• /
• 제2권4호
• /
• pp.293-307
• /
• 2005

The development and the main features of an expert system for modeling the requirements of durable concrete in chemical exposure, called the Durable Concrete Advisor for Chemical Exposure (DCACE), are described. The system was developed to help improve the quality of concrete exposed to chemical environment by minimizing mistakes and deficiencies in selecting concrete constituents. Using Kappa-PC expert system shell, an object-oriented model was developed where the rule-based reasoning operates on or across objects. The American Concrete Institute manual of concrete practice was chosen as the main source of knowledge. Other textual sources were also consulted for knowledge acquisition. The major objectives of the research were acquisition and formalization of the relevant knowledge and building an expert system for making durable concrete for chemical exposure regarding sulfate attack, acid attack, seawater attack and carbonation. Similar to most expert systems, this system has explanation facilities, can be incrementally expanded, and has an easy to understand knowledge base. The performance of the system is demonstrated by an example session. The system is user-friendly and can be used as an educational tool.

• 한국농공학회지
• /
• 제43권1호
• /
• pp.96-101
• /
• 2001

In designing the greenhouse structures, snow and wind loads must be estimated on the basis of the probability of occurrence of snow or wind storms of a given intensity. The recurrence interval chosen depends on the standard durable years and safety factors of the greenhouse. This study was carried out to find the standard durable years of pipe framed greenhouses. Bend test for metallic materials was conducted on samples of galvanized steel pipes being used in greenhouse frames. A secular change of collapse loads and flexural rigidity for galvanized steel pipes were analyzed with the parts buried in the ground and exposed in the atmosphere. From those experimental results and corrosion rate of galvanized film, the standard durable years for pipe framed greenhouses are estimated as follows ; the small scale pipe houses of movable type is 7∼8 years and the large scale pipe houses of fixed type is 14∼15 years.

• 한국염색가공학회지
• /
• 제10권5호
• /
• pp.24-31
• /
• 1998

The effects of DMDHEU alone and DMDHEU/Fluorochemical(FC) combined treatment on the physical properties of 75％/25％ cotton/polyester(CP) blended fabrics were investigated. FC water repellent and DMDHEU durable press finishes were applied in combination to CP fabrics to provide good water repellency as well as great durable press(DP) performance. The physical properties of the fabrics were evaluated by wrinkle recovery angle(WRA), DP performance, contact angle, demand wettability, and water repellency. The durable press/water repellent finished(DP/WR) CP fabrics show considerably improved WRA and DP performance. The DP/WR finishes do not change the water contact angie of polyester fibers significantly, while the DP finishes increase it. Both DP and DP/WR finishes increase the contact angle of cotton fibers. The water uptake amount increases in the following order : DP/WR cotton, DP/WR CP＜DP cotton, DP CP ＜ Control CP, Control cotton. The water uptake amount increases in the following order DP/WR CP, DP/WR cotton ＜DP cotton ＜DP CP＜Control CP, Control cotton. Considerable improvements for water repellency are imparted to the CP fabrics treated with DP/WR, and the level of improvement is not significantly different from that of the DP/WR cotton fabrics. These results lead to the conclusion that DP/YVR treatments a single pad bath on CP are effective finishes for improving both DP performance and water repellency.