• Title/Summary/Keyword: change of variables

Search Result 2,583, Processing Time 0.034 seconds

Expectation-Based Model Explaining Boom and Bust Cycles in Housing Markets (주택유통시장에서 가격거품은 왜 발생하는가?: 소비자의 기대에 기초한 가격 변동주기 모형)

  • Won, Jee-Sung
    • Journal of Distribution Science
    • /
    • v.13 no.8
    • /
    • pp.61-71
    • /
    • 2015
  • Purpose - Before the year 2000, the housing prices in Korea were increasing every decade. After 2000, for the first time, Korea experienced a decrease in housing prices, and the repetitive cycle of price fluctuation started. Such a "boom and bust cycle" is a worldwide phenomenon. The current study proposes a mathematical model to explain price fluctuation cycles based on the theory of consumer psychology. Specifically, the model incorporates the effects of buyer expectations of future prices on actual price changes. Based on the model, this study investigates various independent variables affecting the amplitude of price fluctuations in housing markets. Research design, data, and methodology - The study provides theoretical analyses based on a mathematical model. The proposed model uses the following assumptions of the pricing mechanism in housing markets. First, the price of a house at a certain time is affected not only by its current price but also by its expected future price. Second, house investors or buyers cannot predict the exact future price but make a subjective prediction based on observed price changes up to the present. Third, the price is determined by demand changes made in previous time periods. The current study tries to explain the boom-bust cycle in housing markets with a mathematical model and several numerical examples. The model illustrates the effects of consumer price elasticity, consumer sensitivity to price changes, and the sensitivity of prices to demand changes on price fluctuation. Results - The analytical results imply that even without external effects, the boom-bust cycle can occur endogenously due to buyer psychological factors. The model supports the expectation of future price direction as the most important variable causing price fluctuation in housing market. Consumer tendency for making choices based on both the current and expected future price causes repetitive boom-bust cycles in housing markets. Such consumers who respond more sensitively to price changes are shown to make the market more volatile. Consumer price elasticity is shown to be irrelevant to price fluctuations. Conclusions - The mechanism of price fluctuation in the proposed model can be summarized as follows. If a certain external shock causes an initial price increase, consumers perceive it as an ongoing increasing price trend. If the demand increases due to the higher expected price, the price goes up further. However, too high a price cannot be sustained for long, thus the increasing price trend ceases at some point. Once the market loses the momentum of a price increase, the price starts to drop. A price decrease signals a further decrease in a future price, thus the demand decreases further. When the price is perceived as low enough, the direction of the price change is reversed again. Policy makers should be cognizant that the current increase in housing prices due to increased liquidity can pose a serious threat of a sudden price decrease in housing markets.

An Exploratory Study on the Relationships among the Future Work-Family Compatibility, Gender Attitude of Couples, and Reasons for Low Birth Rate (미혼 남녀의 향후 일.가정 양립 방안, 부부 성역할 태도, 저출산 문제에 대한 견해 간 관계 탐색 연구)

  • Um, Myung-Yong;Kim, Hyo-Soon
    • Korea journal of population studies
    • /
    • v.34 no.3
    • /
    • pp.179-209
    • /
    • 2011
  • This study explored the relationships among such variables as work-family compatibility, gender attitude, reasons for low birth rate, and education level, using a sample of 2,678 from the '2009 National Survey for Marriage and Birth Trend'. The purpose of this study was to identify the ideas about how to support married couples' work-family balance, and how to change gender attitude to promote childbirth. The results are as follows. The type of ideal work-family balance was different by education level, but not by gender. Low level of education was associated with choice of the full time work without a child. Male singles, compared to female singles, preferred the role of a man as a bread winner, and a woman as a house worker. Female singles had the higher level of hope for husband's capability of caring children. This trend was intensified by choice of the full time work with 2 children. Singles who prefer working as a full time worker with 2 children worried more about low birth rate in Korea than singles who prefer working as a part time worker with one or two children. The most frequently cited reason for low birth rate was 'high cost of both child care and education'. The next was 'difficulty in buying a residence, followed by 'increase in the number of career woman'. Female singles who want to work full time with 2 or more children worried more about the burden of child caring and education than male singles. Implications and suggestions were provided based on the results.

Effects of Ballet Program Training of Royal Academy of Dance on Body Composition, Physical Fitness and Bone Mineral Density in College Women (로얄 아카데미 발레댄스 프로그램 수행이 여자 대학생의 신체조성, 체력 및 골밀도에 미치는 영향)

  • Kim, Jong-Won;Lee, Mi-Ran;Lee, Kyung-Hee;Kim, Hyung-Jun;Choi, Mun-Ki;Kim, Do-Yeon;Kim, Tae-Un
    • Journal of Life Science
    • /
    • v.19 no.8
    • /
    • pp.1093-1103
    • /
    • 2009
  • The purpose of this study was to analyze the effects of ballet program training at the Royal Academy of dance (RAD) on body composition (BC), physical fitness (PF) and bone mineral density (BMD) in college women. The subjects for this study were 14 females aged 19 to 22, who were divided into the Experimental group (n=7, EG) and the Control group (n=7, CG). The RAD ballet program training was done by 7 subjects (EG), 60 minutes per day, three times a week for 12 weeks. The TBF and %fat significantly decreased and LBM increased in the Experimental group, but all the variables of Body composition in the Control group did not significantly changed. The AMS, Sit ups, STF, SLJ CFB and 1,200 m R & W in the EG significantly increased, but 1,200 m R & W in the CG decreased. The lumbar vertebra (LV), femoral neck (FN), greater trochanter (GT) and ward's triangle (WT) did not significantly change in the EG, but LV, GT and WT in the CG decreased. There was no significant difference in osteopenia for EG, but there were increases in GT and WT for the CG. There was significant correlation between BMDs and body weight, TBF, LBM, %fat, BMI, AMS. There was significant correlation between LV and FN and LV and whole body. In conclusion, regular and continuous RAD training was effective in improving the body composition, physical fitness and bone mineral density. Consequently, RAD training will be effective for preventing osteopenia and osteoporosis, and for improving the health-related fitness for college and middle-aged women.

Default Risk Mitigation Effect of Financial Structure and Characteristic in BOT Project Finance (BOT 프로젝트 파이낸스의 금융구조 및 특성의 채무불이행 위험완화 효과)

  • Jun, Jae-Bum;Lee, Jae-Sue;Lee, Sam-Su
    • Korean Journal of Construction Engineering and Management
    • /
    • v.12 no.2
    • /
    • pp.121-132
    • /
    • 2011
  • One of the advantages of BOT PF(Project Finance) is the government can be protected from risks involved in projects as the private finances, builds, and operates relevant projects. Moreover, the private may avoid outstanding responsibility in case of default thanks to BOT PF's unique financial structure and characteristics. However, despite increasing attention on risk mitigation effect of financial structure and characteristic of BOT PF to default risk with emerging controversies of capital crunch, introduction of IFRS, and contingent liabilities, valuation of default risk mitigation effect caused by financial structure and characteristics of BOT PF still seems sophisticated due to uncertain cash flows, complexly layered contracts, and their interaction. So, this paper is to show the theoretical frame to assess the default risk mitigation effect of financial structure and characteristic of BOT PF with option pricing and related financial economic theories and to provide some meaningful implications. Finally, this research shows that the financial structure and characteristics of BOT PF help mitigate the default risk and default risk mitigation effect increases as change of relevant variables on financial feasibility gets the BOT project less financially feasible.

Survival analysis on the business types of small business using Cox's proportional hazard regression model (콕스 비례위험 모형을 이용한 중소기업의 업종별 생존율 및 생존요인 분석)

  • Park, Jin-Kyung;Oh, Kwang-Ho;Kim, Min-Soo
    • Journal of the Korean Data and Information Science Society
    • /
    • v.23 no.2
    • /
    • pp.257-269
    • /
    • 2012
  • Global crisis expedites the change in the environment of industry and puts small size enterprises in danger of mass bankruptcy. Because of this, domestic small size enterprises is an urgent need of restructuring. Based on the small business data registered in the Credit Guarantee Fund, we estimated the survival probability in the context of the survival analysis. We also analyzed the survival time which are distinguished depending on the types of business in the small business. Financial variables were also conducted using COX regression analysis of small businesses by types of business. In terms of types of business wholesale and retail trade industry and services were relatively high in the survival probability than light, heavy, and the construction industries. Especially the construction industry showed the lowest survival probability. In addition, we found that construction industry, the bigger BIS (bank of international settlements capital ratio) and current ratio are, the smaller default-rate is. But the bigger borrowing bond is, the bigger default-rate is. In the light industry, the bigger BIS and ROA (return on assets) are, the smaller a default-rate is. In the wholesale and retail trade industry, the bigger bis and current ratio are, the smaller a default-rate is. In the heavy industry, the bigger BIS, ROA, current ratio are, the smaller default-rate is. Finally, in the services industry, the bigger current ratio is, the smaller a default-rate is.

The effects of the value of performing art on attitude and customer satisfaction (공연예술에 대한 가치가 태도와 고객만족도에 미치는 영향에 관한 연구)

  • Koo, Eun-Ja;Park, Su-Jin;Ahn, Sung-Sik
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.17 no.9
    • /
    • pp.543-551
    • /
    • 2016
  • Recently, the cultural industry has become an attractive industry which is having a dramatic effect with the rise of Hallyu offering many possibilities for development. Specially, the marketing techniques employed by the performing arts industry started to change to respond to consumer tastes and demands like other commodity markets, as the popular performing arts industry began to receive attention as a promising industry. It is important to identify the behavior of consumers in order to actively deal with the demands and tastes of consumers that are becoming increasingly diverse and individualized. The performing arts market needs to recognize the importance of its audience and to apply appropriate marketing techniques. This study attempted to empirically identify the value of performing arts perceived by the audience and to investigate the influence of the relationship between the perceived value, attitude formation and satisfaction with performing arts. In order to examine the influence of the value of performing arts on attitude and customer satisfaction, a reliability analysis and factor analysis were conducted to investigate the dependability and validity of the measured variables. In order to achieve the study's intended purpose, the structural equation model (SEM) was utilized as the core analysis method. As a result, it was found that the perceived value and attitude towards performing arts have a positive effect on customer satisfaction. The results of this study are expected to be used as the basic data for organizations that plan performances to improve their marketing and promotion around the audience and for more specific and detailed research in the future.

MD Simulation Study for Preferred Structure of Glycerol Backbone in 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) Molecule According to Solvent Properties (용매 특성에 따른 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) 분자에서 글리세롤 골격 구조에 대한 MD 시뮬레이션 연구)

  • Yang, Ji-yun;Huh, Eugene;Ahn, Ik-sung;Mhin, Byung-jin
    • Journal of the Korean Chemical Society
    • /
    • v.65 no.3
    • /
    • pp.179-184
    • /
    • 2021
  • In this study, the molecular dynamics simulation of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) single molecule was conducted by changing the solvent properties in order to investigate the change in the glycerol backbone structure in phospholipids according to the solvent properties. DOPC has three different conformations according to glycerol C1-C2 bond: A(θ3 = trans, θ4 = gauche), B(θ3 = gauche, θ4 = gauche-), C(θ3 = gauche-, θ4 = trans). Changes in the glycerol backbone structure of the DOPC were examined using the solvent's dielectric constant and surface tension constant as variables. As a result, the population of the B structure increased as the dielectric constant increased. The reason is that the solvation energy of the B structure is larger than that of A. In addition, as the surface tension constant increased, the population of the B structure increased because the surface area of B was smaller than that of A. The results of these studies are expected to be used in the study of phospholipid structure in the future.

Experimental Study on the Ground Behavior around a Tunnel due to the Sidewall Deformation of Shallow Tunnel in Longitudinal Direction Excavated under the Slope (사면 하부지반에 종단 방향으로 굴착한 얕은 터널에서 측벽변형에 따른 터널 주변지반의 거동에 대한 실험적 연구)

  • Na, Yong Soo;Lee, Sang Duk
    • Journal of the Korean Geotechnical Society
    • /
    • v.35 no.5
    • /
    • pp.21-30
    • /
    • 2019
  • While the study of the shallow tunnel has been mainly on the longitudinal load transfer and horizontal surface conditions, the study of the ground behavior of shallow tunnel under the slope is not sufficient. Therefore, in this study on the ground behavior around a tunnel due to the sidewall deformation of shallow tunnel under the slope that is excavated in longitudinal direction, a scale-down model test has been performed. The model tunnel has the dimension of 320 mm wide, 210 mm high and 55 mm long with enough material strength in aluminum and the model ground has the uniform ground conditions by 3 types of carbon rods. The model test has been performed with the variables of slopes and the cover depths by controlling the tunnel sidewall deformation, and the change of sidewall-load, load transfer, ground subsidence was monitored and analyzed. According to the increase of the slope, the maximum ground subsidence increased by 20~39% compared to the horizontal surface. The load ratio increased by maximum 20% in the tunnel crown and decreased in sidewall according to the surface slope. The load transfer shows maximum 128% of increase at the cover depth of 1.0D, while at the 1.5D cover depth it shows non-critical difference from horizontal surface. The slope has major effects on load transfer at the cover depth of 1.0D.

Strength Characteristics of 3D Printed Composite Materials According to Lamination Patterns (적층 패턴에 따른 3D 프린팅 복합재료의 강도특성)

  • Seo, Eun-A;Lee, Ho-Jae;Yang, Keun-Hyeok
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.25 no.6
    • /
    • pp.193-198
    • /
    • 2021
  • In this study, the rheological characteristics and of 3D printing composite materials and the compressive strength characteristics according to the lamination patterns were evaluated. As a result of rheology test, rapid material change was observed after 60 minutes of extrusion, yielding stress 1.4 times higher than immediately after mixing, and plastic viscosity was 14.94-25.62% lower. The compressive strength of the specimens manufactured in the mold and the laminated specimens were compared, and the lamination pattern of the laminated specimens were 0°, 45°, and 90° as variables. The compressive strength of the mold casting specimen and the laminated specimen from 1 to 28 days of age showed similar performance regardless of the lamination pattern. In particular, at the age of 28 days, the modulus of elasticity, maximum compressive strength, and strain at maximum stress of all specimens were almost the same. In order to analyze the interface of the laminated specimens, X-ray CT analysis of the specimen whose compressive strength were measured was performed. Through CT analysis, it was confirmed that cracks did not occur at the lamination interface, which can be judged that the interface in the laminated specimen behaved in an integrated manner.

An Experimental Study on Concrete Bond Behavior According to Grid Spacing of CFRP Grid Reinforcement (격자형 CFRP 보강재의 격자간격에 따른 콘크리트 부착거동에 대한 실험적 연구)

  • Noh, Chi-Hoon;Jang, Nag-Seop;Oh, Hongseob
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.26 no.6
    • /
    • pp.73-81
    • /
    • 2022
  • Recently, as the service life of structures increased, the load-carrying capacity of deteriorated reinforced concrete, where corrosion of reinforcing bars occurs due to various causes, is frequently decreased. In order to address this problem, many studies on the bond characteristic of FRP (Fiber Reinforced Polymer) bars with corrosion resistance, light weight and high tensile strength have been conducted, however there are not many studies on the bond characteristic of grid-typed CFRP embedded in concrete. Therefore, in order to evaluate the bond characteristics of grid-typed CFRP and its usability as a substitute for steel rebar, a pull-out test is performed using the longitudinal bond length and transverse grid length of the grid-typed CFRP as variables. Through the pull-out test, the bond load-slip curve of the grid-typed CFRP is derived, and the bond behavior is analyzed. The total bond load equation is proposed as the sum of the bond force of the longitudinal bond length and the shear force of the grid in the transverse direction. Also, expressing the area of the bond load-slip curve as total work, the change in dissipated energy with respect to the slip is analyzed to examine the effect of the tranverse grid on the bond force.