역사는 반복된다. 모두 비극으로

김덕민 문화과학사 2013 문화과학 Vol.- No.73

희토류 추출공정 잔사 및 수처리 슬러지의 안정화/고형화 평가

김덕민,고명수,박미선,박미정,지원현,김승섭,이상환 한국자원공학회 2017 한국자원공학회지 Vol.54 No.2

For residue and water treatment sludge from extraction process of rare earth elements in China, addition of stabilizing/solidifying agents was evaluated by Toxicity Characteristic Leaching Procedure (TCLP). Coal mine drainage sludge mixed at 10% ratio removed 76% and 67% of As and Se, respectively, from the sludge. Ferrous sulfate mixed at 2% ratio removed 99% of Ba. Bone char mixed at 10% ratio removed 82%, 86% and 92% of Be, Ba and Pb, respectively, possibly because of its micro-structure. Be, Pb, and Th were reduced to <0.08 mg/L at a cement amendment ratio of 10%. As and Se decreased by 98.0~99.9% and 54.7~98.6%, respectively, after amendment of cement at mixing ratios of ≥ 20%, suggesting formation of Ca-As and Ca-Se complex. However, Se increased at pH>10.5, indicating increase of mobility. 중국 희토류 추출잔사 및 수처리 슬러지를 대상으로 안정화/고형화제의 적용성을 TCLP(Toxicity Characteristic Leaching Procedure)로 평가하였다. 희토류 슬러지에 광산배수 슬러지 10% 혼합시 As 76%, Se 67%가저감되었으며 Ba은 FeSO4 2% 혼합시 99%까지 저감되었다. Biochar는 10% 처리시 Be, Ba, Pb을 각각 82%, 86%, 92% 저감하였으며, 이는 발달된 미세구조의 영향으로 판단된다. 잔사의 시멘트 10% 처리 결과 Be, Pb, Th이 0.08 mg/L 이하로 저감되었다. As 및 Se은 시멘트 20% 이상 처리시 각각 98.0~99.9%, 54.7~98.6%만큼 저감되어 Ca-As 및 Ca-Se 화합물을 생성한 것으로 추정된다. 그러나 Se은 약 10.5 이상의 pH 조건에서 이동성이 증가하는 것으로 확인되었다.

시스템 다이내믹스와 새케인즈주의 모형

김덕민 한국시스템다이내믹스학회 2019 한국시스템다이내믹스 연구 Vol.20 No.4

This article explores the dynamic characteristics of the basic new Keynesian model which is widely used in lots of the central banks in each country and educated for the advanced macroeconomics at the graduate level in economics. System dynamics can give help to reveal the dynamic states of the basic model. In this article, the particular assumptions or determination with regard to the basic model such as jump variables and determinacy or indeterminacy of the model, which make lots of students and nonspecialists difficult to understand the model, can be easily found by help of the computer-aided simulation of system dynamics and some further related studies.

Secular Stagnation - The US and Korean Economies -

김덕민 호남대학교 인문사회과학연구소 2023 인문사회과학연구 Vol.66 No.3

This paper discusses the technical patterns behind the discussion of secular stagnation in the US economy since 2000. The measure of TFP growth we use is a single weighted average of capital and labor productivity growth. This allows us to see the long-run changes in each productivity growth that affect TFP growth. We also use the Korean economy as a catch-up economy to see if the technical patterns of the US economy are repeated in the Korean economy. In terms of TFP growth, the 1970s is the worst period for both countries. TFP growth picks up after the 1980s in the US economy and after 1997 in the Korean economy. However, a technical pattern similar to the 1970s reappears after the 2000s in the US economy and after the 2010s in the Korean economy.

Domestic demand under Neoliberalism: the US and Korean Economy

김덕민 호남대학교 인문사회과학연구소 2020 인문사회과학연구 Vol.63 No.3

This article explores long-term relationships between macroeconomic trajectories and wage inequality under neoliberalism in the US and S. Korea. The evolution of consumer debt during the neoliberal period is also considered in this study. Both countries suffered from economic crises such as the global crisis of 2008 or the Asian financial crisis in 1997-8. To capture these structural changes in both countries, we use some unit root tests with structural changes and a cointegration test with a single structural break. In this study, we found long-term patterns between domestic demand, wage inequality, and consumer debt that much of literature on neoliberalism has expected: a positive long-term relationship between consumption, wage inequality, and consumer debt; a negative long-term relationship between investment, wage inequality, consumer debt; however, if taking the structural changes in both countries, the result is quite different from the expectations in both countries.

Profit rates: Current Cost vs. Historical Cost

김덕민 경상대학교 사회과학연구원 2012 마르크스주의 연구 Vol.9 No.4

The main purpose of this paper is an analysis of profitability trends prior to the 2007 financial crisis. First of all, we discuss the importance of profit rate in economic analysis. Profit rate is the variable that not only expresses business capacity but also strongly impacts on capitalist investment decision-making. Thus there can be various definitions of profit rates suitable for each circumstance. We trace the pre-crisis trends of profitability in the US economy, particularly by the profit rates that are estimated by using current-cost and historical cost net capital stock. Besides these general profitability trends (profit rate á la Marx), considering taxation, we estimate after-tax profit rates using current cost and historical cost capital stock as the denominators. Concerning capitalist decision-making and data reliability, we suggest that historical cost profit rate is irrelevant to the analysis of profitability trends.

인구 변화의 경제성장에 대한 영향: 기술변화의 확률 모형을 이용한 예측

김덕민 한국사회경제학회 2022 사회경제평론 Vol.35 No.2

This paper predicts changes in the major variables of the Korean economy (capital productivity, labor productivity, wage share, and profit rate) and the potential growth rate per capita from 2000 to 2070 using a stochatic model of technical change. The predicted technology variables such as capital and labor productivity and distributional variable such as the share of wages are results of economic activities based on profitability. In this paper, demographic change was set as a variable that influenced technology and distribution. The growth rate per capita of the Korean economy steadily declines until the 2060s. The level of potential growth per capita can be improved due to changes in labor participation rate, employment rate, working hours per employee, and technical conditions. The model of this paper shows that efforts to cope with changes in the demographic structure are urgent and must be made dramatically. 이 논문은 기술변화의 확률 모형을 사용하여 2000-2070년까지 한국경제의 주요 변수들(자본생산성, 노동생산성, 임금몫, 이윤율)과 일인당 성장률의변화를 예측한다. 예측된 자본생산성 및 노동생산성 기술변수와 임금몫 분배변수는 수익성에 기초한 경제적 활동의 결과이다. 인구구조의 변화는 기술적 조건에 영향을 주며, 노동시장 조건을 변화시켜 임금률 결정에도 영향을 준다. 이에 따라 한국경제의 일인당 성장률은 2060년대까지 꾸준히 하락한다. 노동 참가율, 고용률, 취업자당 노동시간, 기술적 조건의 변화로 일인당 성장률 수준은 개선될 수 있다. 이 논문의 모형은 인구구조의 변화에 대응하는 노력이 시급하고, 획기적으로 이루어져야 함을 보인다.

자연정화 슬래그반응조 및 Active 처리시설에서의 광산배수 내 망가니즈 저감: 처리시설 설계를 위한 제언

김덕민 한국자원공학회 2021 한국자원공학회지 Vol.58 No.3

Although Mn frequently exceeds the effluent standard in South Korea, only active treatment facilities were applied to remove Mn because it was difficult to be removed by passive treatment. Because a slag reactor that removes Mn by passive treatment is being designed, design factors were proposed by relevant studies. The factors include differences in hydraulic head, the composition of substrate, variations in treatment efficiency, and the residence time. Moreover , the required pH decreases by the coprecipitation and sorption of Mn by Fe and Al hydroxides in active treatment facilities. To design efficient active treatment facilities considering the necessity of a pH readjustment tank, a relationship between the required pH and the concentrations of Fe, Al, and Mn was also proposed from relevant studies. 망가니즈는 국내 광산배수에서 철에 이어 두 번째로 배출허용기준을 많이 초과하는 원소이나, 자연정화하기 어려워 그간 active 시설에서 처리해 왔다. 망가니즈 제거용 자연정화시설인 슬래그반응조가 도입 단계에 있으며, 이의 설계 인자들에 대하여 관련된 연구들로부터 제안하였다. 설계 인자는 필요 수위차, 매질 구성, 처리효율 변화, 그리고 체류시간을 포함한다. 또한, 기존의 active 처리시설에서 망가니즈가 철 및 알루미늄에 의해 공침 및 흡착 기작으로 제거되므로 처리를 위해 필요한 pH가 낮아지는데, pH 재조정조의 반영 여부 등을 판단해 효율적인 active 처리시설을 설계하기위하여 Fe, Al 및 Mn 농도로부터 처리 pH를 추정하는 관계도 관련 연구로부터 제안하였다.

새로운 마르크스읽기, 오래된 마르크스읽기 『생각하는 마르크스』 서평

김덕민 경상대학교 사회과학연구원 2018 마르크스주의 연구 Vol.15 No.1

This article is a critical reading of Professor Baek Seung-wook’s new book, How Marx? It attempts to generalize Marxian theory to the theory of sociality, suggesting a new interpretation of the former. However, compared to Jacques Bidet’s “Theory of Modernity”, we can find that the Pr. Baek’s new reading contains some deficiencies. There seem to be some problems in the design and organization of concepts. Nevertheless, it should be evaluated as a new attempt to read Marx. 중앙대 백승욱 교수의 『생각하는 마르크스』는 마르크스의 저작들에 대한 재해석을 통해 마르크스 이론의 사회성 이론과의 통합을 시도한다. 이러한 시도는 완전히새로운 것은 아닌데, 프랑스의 에티엔 발리바르나 자크 비데와 같은 철학자들, 그리고 한국의 윤소영 교수에 의해 소개되고 시도된 바 있다. 이 논문에서는 주로 자크비데의 ‘현대성 이론’과의 비교를 통해 『생각하는 마르크스』의 시도가 갖는 의의와결함을 짚어보았다. 『생각하는 마르크스』가 던지고 있는 마르크스 이론의 사회이론의 일반화 작업은 경제적 구조와 이데올로기적 구조의 결합을 시도하지만, 여전히여러 한계를 노출하고 있으며, 오히려 이런 시도를 통해 마르크스 이론의 자본주의생산양식 분석과 계급이론으로서의 지위를 탈각시키는 효과가 존재한다. 그럼에도불구하고 이러한 새로운 시도는 마르크스에 대한 관심을 환기시키기에 충분한 것으로 보인다.

시스템 다이내믹스에 기초한 비선형 경제성장 모형

김덕민 한국시스템다이내믹스학회 2018 한국시스템다이내믹스 연구 Vol.19 No.1

This paper aims to build a nonlinear dynamic model of economic growth using system dynamics. The model in this study is an application of Goodwin’s model in 1990, but the level dimension of the model in 1990 is transformed into a the-rate-of-change dimension in this study. The model is constructed using system dynamics elements: the stock-flow structures, multiple feedback mechanisms, and time delays. The model successfully implemented the reconstruction of persistent and unpredictable movements of variables on the dimension of the rate of change. This study suggests another perspective regarding the concept of equilibrium besides the traditional point of view that mainly described in the comparative statics. Complex movements of the variables can be generated in a simple deterministic system. Therefore, the stability of a model has to be discussed based on a whole system, which can be evaluated only in the interrelationship of multiple feedback loops with time delays.