지역산업연관표를 이용한 지방재정자립도 제고방안에 관한 연구 : 5대 광역시를 중심으로

양현석(Yang Hyun Seok) 한국재정학회(구 한국재정·공공경제학회) 2008 한국재정학회 학술대회 논문집 Vol.2008 No.1

본 연구는 인과관계분석과 지역산업연관표를 이용하여 지역의 세입에 영향을 주는 산업과 지역경제활성화에 영향을 주는 산업을 선정하는데 그 목적이 있다. 통계청과 한국은행의 산업분류가 상이한 관계로 본 연구는 산업조정을 시작으로 Granger 인과성 검정을 통해 세입에 영향을 주는 산업을 1차적으로 선정하였다. 2003년 전국산업연관표를 RAS법을 이용하여 2006년 전국산업연관표로 업데이트 한 후 입지계수법을 이용하여 5대 광역시의 지역산업연관표를 작성하였다. 인과관계 분석에서 세입에 영향을 주는 산업으로 나타난 산업과 지역별로 각종계수 1위~6위에 해당하는 산업을 분석하여 산업을 선정하였다. 구체적으로 부산의 경우에는 가공조립형 제조업, 숙박 및 음식점업, 광주의 경우 기타서비스업, 대전의 경우에는 가공조립형 제조업, 인천의 경우에는 생활관련형 제조업이 선정되었다. 이는 재정자립도 제고와 지역 경제활성화라는 목적을 동시에 달성할 수 있는 산업을 의미하는 것이다. The purpose of this study is to select the industries which have influences on the revenue of region and on growth of regional economy using correlation analysis and regional input output analysis. Since the National Statistic Office and the Korea Bank have different criteria for industry assortment, those which affect the revenue of region are select first using the Granger Causality Test after reassorting industries in order to match them between criteria of the National Statistic Office and the Korea Bank. After updating the 2003 input output table to 2006 by the bi-proportional adjustment method, so called 'RAS' method, we built up the regional input output tables of the five metropolitan cities with a location quotient (LQ) method. We selected the industries, for each of five metropolitan cities, which were presented to have great influence on the revenue of region by the Granger Causality Test and also presented to be the top 1 to 6 to have great coefficients for the growth of regional economy through the regional input output analysis. For Pusan, Processing Assembly Industry, Hotels and Restaurants, for Gwangju, Activities of other service, for Taejeon, Processing Assembly Industry, for Incheon, Living & Other Industry were selected respectively. It means that those individual industries can make it to achieve not only the reinforcement of the financial self-sufficiency of each local government, but also economic growth of the region at the same time.

지역산업연관모형과 재정자립도 제고 방안에 관한 연구 : 광주광역시를 중심으로 Based on the case study of Gwang-ju city

양현석 ( Hyun Seok Yang ),정군오 ( Kun Oh Jung ) 한국재정정책학회 2008 財政政策論集 Vol.10 No.1

공공임대주택수요 추정 및 예측에 관한 연구: 가계조사자료를 이용한 미시적 접근

양현석 ( Hyun Seok Yang ),김원년 ( Won Nyun Kim ) 韓國財政政策學會 2009 財政政策論集 Vol.11 No.2

본 연구는 저소득층의 주거안정을 위한 공공임대주택수요를 추정하고 예측하는데 그 목적이 있다. 이를 위해 M-W 확장모형을 구축하고 회귀계수를 추정, 이를 이용하여 2020년까지의 공공임대주택수요를 예측하였다. 주요 결과를 살펴보면 연령구간별 회귀계수는 선행연구와 다소 차이를 보이면서 30대 구간에 정점에 이르고, 75세 구간에 다시 한 번 정점에 이른다. 즉 공공임대주택의 주된 수요 연령계층이 30대임을 확인할 수 있었고, 고령화 추세에 의해 70대 고령층 또한 공공임대주택의 수요 연령계층임을 보여주었다. 항상소득과 주거비용은 예상한 바와 같이 소득은 주택수요에 양(+)의 효과를, 주거비용은 음(-)의 효과를 보였다. 주택수요는 주거비용에 비해 소득의 변화에 상대적으로 민감하게 나타났으며 이는 소득과 주거비용이 동일한 비율로 증가하는 경우 소득의 영향이 상대적으로 높아 주택수요는 지속적으로 증가할 것임을 의미한다. 실증분석으로 도출된 연령구간별 계수와 항상소득, 주거비용에 관련된 다양한 가정으로 기반으로 예측된 공공임대주택수요량(호수)은 214만호 수준이며, 매년 3~4만호 수준의 건설이 지속적으로 이루어져야 한다는 결론이 도출되었다. The purpose of this study is to estimate the public rental housing demand using Household Expenditure Survey in Korea. We set an expanded M-W model by adding permanent income and housing cost as explanatory variables into the model, which was proposed by Mankiw and Weil (hereafter `M-W model`) in 1989. And we estimated coefficients for housing demand of each of age group by 5 years interval. Using the estimated coefficients and the estimated numbers of population and household, we predicted the demand of the public rental housing till 2020. As expected, The result of the estimation of coefficients of permanent income was positively, the coefficients of housing cost was negatively and significantly estimated. We`ve obtained different results for the coefficients of household members by age intervals, the peak of coefficients of age intervals was 30~34 and 74~79. It implies that the thirties and seventies are a major age group the demand of the public rental housing. The estimated quantites of the public rental housing demand were about 2,140,000 dwellings. And the public rental housing demand of 30,000-40,000 dwellings will constantly occur every year without consideration of housing depreciation.

분무건조 방법의 차이가 글리메피라이드 함유 고체분산체의 특성에 미치는 영향

양현석(Hyun Seok Yang),오유림(Yu Rim Oh),김동욱(Dong Wuk Kim) 대한약학회 2021 약학회지 Vol.65 No.6

Glimepiride (GLI) is a third-generation sulfonylurea class antidiabetic drug that has low aqueous solubility. The objective of this study was to evaluate the effect of solvents in the development of GLI-loaded solid dispersions (GLISD) using spray drying technique. Two GLI-SD were prepared by adding GLI, polyvinylpyrrolidone (PVP K30), and sodium lauryl sulfate (SLS) in an ethanol/water mixture (solvent evaporation, SE) and water only (surface attached, SA). Intrinsic saturated solubilities and in-vitro dissolution were evaluated and compared to the GLI powder and physical mixture (PM). In addition, physicochemical studies such as scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction were also evaluated. We found that the solubility of GLI was significantly improved by both the preparation methods. The SE method showed 4,960-fold improvement while the SA method displayed 2,900-fold enhancement, which is equivalent to the PM. The in-vitro dissolution studies showed that both methods had a higher release rate, about 1.3-fold for SE and 2-fold for SA, as compared to pure GLI powder. However, GLI release slightly decreased with time for the SA method. Furthermore, solid-state characterizations also revealed that most of the crystalline drug was transformed to the amorphous form in both GLI-SD. Thus, these results indicate that choice of the solvent system plays an important role in the spray drying technique which affects the solubility, dissolution, and crystallinity of poorly soluble drugs such as GLI.

공압인공근육을 이용한 조작기 위치의 강인제어

박노철,양현석,박영필,Park, No-Cheol,Yang, Hyun-Seok,Park, Young-Pil 대한기계학회 1996 大韓機械學會論文集A Vol.20 No.6

This paper is concerned with the position control of the ond degree-of freedom manipulator using pneumatic artificial muscle actuator which is built to have a proper compliance. For t his pneumatic artificial muscle actuator though, it is difficult to make an effective control scheme due to the nonlinearity and uncertainties on the dynamics of the actuator. In this paper, a third-order equation of motion is derived for the actuator including the dynamics of the pneumatic servovalve. Later, various modeling uncertainties due to the nonlinearity and unmodeled dynamics of the servo vlave and the actuator are taken care of, as a trade-off between the closed-loop performance of the controlled system and its robustness to uncertainties. A controller using .mu. synthesis thchnique is designed, and robust performance against measurement noise, various modeling uncertainties due to the dynamics of the servo valve and actuator is achieved. The effectiveness of the proposed control methods is illustrated through simulations and experiments.

Dielectric Elastomer를 이용한 카메라 폰 AF 렌즈 구동기의 설계 및 제어

심현재(Hyun-Jae Shim),김철진(Chul-Jin Kim),정준(Jun Jeong),양현석(Hyun Seok Yang),박영필(Young-Pil Park) 한국소음진동공학회 2005 한국소음진동공학회 학술대회논문집 Vol.2005 No.11

$\mu$-합성법에 의한 유연한 조작기의 위치 및 진동제어

박노철,양현석,박영필,Park, No-Cheol,Yang, Hyun-Seok,Park, Young-Pil 대한기계학회 1996 大韓機械學會論文集A Vol.20 No.10

When a robot is to have contact with its enviornment, such as a medi-care robot, it would be advantageous for the robot to have a high compliance. For this reason, a robot having not only a flexible link but also an actuator with compliance, is desirable. This paper is concerned with the position and vibration control of 1 degree of freedom flexible robot using a pneumatic artificial muscle actuator. The dynamics of the manipulator assumed to be and Euler-Bernoulli beam are derived on the basis of the linear mathematical modle. Although this pneumatic artifical muscle actuator has many merits for the compliance robot, it is difficult to make an effective control scheme of this system because of ths nonlinearity and uncertainty on the dynamics of the actuator. By designing a controller using .mu.-synthesis, robust performance against measurement noise, various modeling uncertainties on the dynamics of the servo valve, actuator and mainpulator, is achieved. The effectiveness of the proposed control method is illustrated through simulations and experiments.

$H_\infty$ 제어를 이용한 방진대의 능동제어

김규용,양현석,박영필,Kim, Kyu-Young,Yang, Hyun-seok,Park, Young-Pil 대한기계학회 1996 大韓機械學會論文集A Vol.20 No.10

Recently, the high-precision vibration attenuation technology becomes the essence fo the seccessful development of high-integrated and ultra-precision industries, and is expected to continue playing a key role in the enhancement of manufacturing technology. Vibration isolation system using an air-spring is widely employed owing to its excellent isolation characteristics in a wide frequency range. It has, however, some drawbacks such as low-stiffness and low-damping features and can be easily excited by exogenous disturbances, and then vibration of table is remained for a long time. Consequently, the need for active vibration control for an air-spring vibration isolation system becomes inevitable. Furthermore, for an air-spring isolation table to be successfully employed in a variety of manufacturing sites, it should have a guaranteed robust performance not only to exogenous disturbances but also to uncertainties due to various equipments which might be put on the table. In this study, an active vibration suppression control system using H.inf. theory is designed and experiments are performed to verify its robust performance. An air-spring vibration isolation table with voice-coil-motors as its actuators is designed and built. The table is modeled as 3 degree-of-freedom system. An active control system is designed based on $H_\infty$control theory using frequency-shaped weighting functions. Analysis on its performance and frequency responce properties are done through numerical simulations. Robust characteristics of$H_\infty$ control on disturbances and model uncertainties are experimentally verified through (i) the transient response to the impact excitation of the table, (ii) the steady-state response to the harmonic excitation, and (iii) the response to the mass change of the table itself. An LQG controller is also designed and its performance is compared with the $H_\infty$ controller.

MoS₂ 첨가에 따른 Fe-Cr-Mn-C-V계 소결합금의 기계적 특성 평가

김건홍,양현석,공만식,Kim, Geon-Hong,Yang, Hyun Seok,Kong, Man-Sik 한국분말야금학회 2014 한국분말재료학회지 (KPMI) Vol.21 No.4

The connecting rod is one of the most important parts in automotive engines, transforming the reciprocal motion of a piston generated by internal combustion into the rotational motion of a crankshaft. Recent advances in high performance automobile engines demand corresponding technological breakthroughs in the materials for engine parts. In the present research, the powder metallurgy (P/M) process was used to replace conventional quenching and/or tempering processes for mass production and ultimately for more cost-efficient manufacturing of high strength connecting rods. The development of P/M alloy powder was undertaken not only to achieve the improvement in mechanical properties, but also to enhance the machinability of the P/M processed connecting rods. Specifically $MoS_2$ powders were added as lubricants to non-normalizing Fe-Cr-Mn-V-C alloy powder to improve the post-sintering machinability. The effects of $MoS_2$ addition on the microstructure, mechanical properties, and machining characteristics were investigated.

스테인리스강의 Nd:YAG 레이저 겹치기 용접부 피로수명에 미치는 용접변수의 영향

김용,양현석,박기영,이경돈,Kim, Yang,Yang, Hyun-Seok,Park, Ki-Young,Lee, Kyoung-Don 대한용접접합학회 2008 대한용접·접합학회지 Vol.26 No.1

Spot welding which use the main process for side block production of stainless steel railway vehicle is legged behind in laser welding about a quality and productivity. Although the laser welding has many potential advantages such as low heat input and aspect ratio of weld bead, its application to a new structural component still is required many engineering data including mechanical properties such as tensile, fatigue strength, etc on. Therefore, experimental analysis was carried out to understand the fatigue phenomena of different thickness stainless steel overlap joining panels by Nd:YAG laser welding. The fatigue life curves were obtained through fatigue tests with the various levels of applied load. The fatigue life is related with the parameters such as gap size and penetration depth through experiment. As the results, tensile strength and fatigue life were proportional in heat input level and gap was identified the major factor for fatigue life. Also we could know that deferent a-ferrite content at HAZ depend on welding heat input was important factor to determine a formation of initial crack and total fatigue life cycle.