냉매 오충전은 에어컨에서 빈번하게 발생하는 고장 모드 중 하나로, 적정 충전량 대비 부족 및 과충전 모두 냉방 성능의 저하를 유 발하므로 충전된 냉매량을 정확하게 판단하는 것이 중요하다. 본 연구에서는 퍼지 군집화 기법을 통한 정상상태 식별을 통해 냉매 오 충전량을 다중 분류하는 모델을 개발하였다. 정상상태 식별을 위해 에어컨 운전 데이터에 대해 이동 평균 간의 차이를 활용한 퍼지 군 집화 알고리즘을 적용하였으며, IFDR를 통해 기존 연구된 정상상태 판단 기법들과 식별 결과를 비교하였다. 이후, 시스템 내 상관성 을 고려한 mRMR을 이용해 특징을 선택하였으며, 도출된 특징을 이용해 SVM 기반의 다중 분류 모델이 생성되었다. 제안된 방법은 시험 데이터를 통해 만족할 만한 분류 정확도와 강건성을 도출하였다.

In the present study, to investigate the cooling characteristics of the multi-heat pump with 3 indoor units, 7 indoor unit combinations and 3 setting temperatures are selected to study the cooling characteristics during steady-state operation. The cooling capacity, power consumption, COP, compressor high and low pressure of the heat pump are tested under the cooling standard temperature conditions using an air enthalpy multi-calorimeter. The experimental results show that, except for an operation with an indoor unit capacity of 30% or less, the cooling capacity, power consumption, and compressor operation frequency increase as the capacity of the indoor unit increases and the setting temperature of the indoor unit decreases. COP increases or decreases according to the compressor frequency, and is the best at 50-80% capacity of the indoor unit. As the compressor frequency increases, the compressor outlet pressure increases by about 30%.

The effect of oxidation time on the characteristics and mechanical properties of spent nuclear fuel cladding was investigated using Raman spectroscopy, tube rupture test, and tensile test. As oxidation time increased, the Raman peak associated with the tetragonal zirconium oxide phase diminished and merged with the Raman peak associated with the monoclinic zirconium oxide phase near 333 cm−1. Additionally, the other tetragonal zirconium oxide phase peak at 380 cm−1 decreased after 100 d of oxidation, whereas the zirconium monoclinic oxide peak became the dominant peak. The oxidation time had no effect on the tube rupture pressure of the oxidized zirconium alloy tube. However, the yield and tensile stresses of the oxidized nuclear fuel cladding tube decreased after 100 d of oxidation. The results of the scanning electron microscopy and transmission electron microscopy were represented with the in-situ Raman analysis result for the oxide characteristics generated on the cladding of spent nuclear fuel.

Microbubbles oxygen transfer to water was simulated based on experimental results obtained from the bubbles generation operated under varying liquid supply velocity to the multi-step orifices of the generator. It had been known that liquid supply velocity and bubble size are inversely related. In the oxygen transfer, a non-steady state was assumed and the pseudo stagnation caused the slow movement of bubbles from the bottom to the water surface. Two parameters were considered for the simulation: They represent a factor to correct the pseudo stagnation state and a scale which represented the amount of bubbles in supply versus time. The sum of absolute error determined by fitting regression to the experimental results was comparable to that of the American Society of Civil Engineers (ASCE) model, which is based on concentration differential as the driving force. Hence, considering the bubbles formation factors, the simulation process has the potential to be easily used for applications by introducing two parameters in the assumptions. Compared with the ASCE model, the simulation method reproduced the experimental results well by detailed conditions.

Introduction Kotler (2015) warned that, if we only pursue economic growth and revenue/profit expansion, we will end up with overconsumption and wastes, bringing serious damage to our planet. He advocated the transition from the growth-oriented economy to the steady-state economy. Steady state economy is defined as an economy that maintains desired sufficient level of throughput with the lowest feasible flows of matter and energy from production to consumption (Kotler, 2015). As Kotler mentioned, this idea is somewhat utopian as most companies are still living in the growth-oriented economy. The purpose of this research is to extend Kotler’s idea by conceptualizing a more concrete model to visualize the marketing in the steady state economy. The model consists of five major elements; customers, stakeholders, employees, suppliers and community. The authors also present twelve propositions that explain promoting factors for the marketing in the steady state economy based on the multiple case studies conducted in Japan. Literature review The steady-state economy itself is actually not a new idea in economics. For example, typical classical economists (e.g., Adam Smith and John Stewart Mill) advocated the transition to the steady-state economy after saturation of economic growth. Neo-classical economists have also postulated the concept of steady state economy with regard to the law of diminishing returns (Tellis, 2008). Many previous studies have continuously put efforts on developing theories and practices to meet with economic, social and environmental needs simultaneously, since Kotler and Zaltman (1971) proposed the concept of social marketing. Although social marketing is closely related to marketing in the steady-state economy, its ethical egotism remains a problem (Crane and Desmond, 2002). Lerman and Shfrin (2015) and Gopaldas (2015) claim positive marketing which creates value for the firm, its customers, and society at large. In short, these concepts suggest the possibility that individual, self-seeking, and short-run behaviors can be consistent with aggregate, altruistic, and long-run behaviors. Besides above exceptions, however, most marketing researchers have evaded the question: What is marketing in the steady-state economy? The purpose of our study is to develop a conceptual framework to analyze “steady-oriented” companies and their marketing strategies based on the case studies in Japan. Research methodology In order to answer the above question, we adopt qualitative heuristic approaches (Kleining, 1994), because our question has not been addressed enough in previous studies mentioned above. First, we collected primary and secondary data from various information sources including company websites, press releases, online business journals, academic case studies, public seminars, presentations at academic meetings and so on (Yin, 2014). As stated by Eisenhardt (1989), we used a theoretical sampling to identify the informants for our multiple case studies. We intentionally chose companies from different industries, locations, length of history, manufacturing technology, etc. Based on the review and data collection, we developed a basic framework and series of theoretical propositions (Yin, 2014). For our study, we selected Japanese companies respecting “sanpo-yoshi” [good for three parties] philosophy. It is a belief that business should be good for sellers, buyers, and society. In fact, positive marketing is similar to this concept of “sanpo-yoshi” which is based on the family precepts of “Ohmi region merchants” in the Edo period (1600-1857) (Ogura, 1991; Usami 2015). Our selected “sanpo-yoshi” oriented companies aim for a harmonious relationship with all the concerning stakeholders and community (see Appendix for the list of selected companies). Figure 1 identifies five key parties covered in the “sanpo-yoshi” management and shows bilateral relations between the company and the five parties. First, “sanpo-yoshi” oriented companies try to build good long-term relationships not only with their customers by selling high-quality products at fair prices, but also with suppliers by buying a stable volume of products at fair prices. In addition, some companies provide their loyal customers with special experience concerning their own brands and their suppliers with technical assistant. In return, customers feel strong loyalty to the brand and suppliers offer a stable supply of high- quality raw materials at fair prices. Moreover, “sanpo-yoshi” companies take an active interest in their employees and the community where they operate because their confidence contributes to sustainable development of the companies. Shareholders for short-term returns, however, are unlikely to give heavy weight to social activities by their investee companies. Therefore, companies whose stocks are unlisted or occupied by long-term shareholders are more favorably inclined toward “sanpo-yoshi” management. Research propositions Based on the case studies of “sanpo-yoshi” companies in Japan, we argue that the enforcement of marketing in the steady-state economy can be tied to three factors: (1) management factors, (2) competitive factors, and (3) financial factors. Within these factors, twelve research propositions are developed for testing in the future research (Eisenhardt and Gaebner, 2007). These factors and propositions are summarized in Figure 2. Management factors are divided into two subcomponents: decision-making and employment factors. First, decision-making factors basically mean that the independence of management from the investors seeking short-term profits enables the management to enforce steady-oriented marketing. The most feasible method is corporate governance by founders or his/her family, although it is not a requirement. For instance, Kagome Co., Ltd. ended the family business operation in 1996, and around 180,000 individual “fan shareholders” accounting for 55.4% (Nikkei, 2017) are supporting the management with a long-term perspective. Second, employment factors indicate that the companies are likely to enforce steady-oriented marketing when they maintain high labor productivity and excellent human resources. In particular, it is more important for companies having many female employees with accumulated experience and know-hows to prevent those employees from quitting the job because of pregnancy or child rearing. Competitive factors are associated with the conditions of the steady state economy surrounding the companies. If the companies have maintained high market share in a mature market for many years, they can afford to enforce “sanpo-yoshi” oriented marketing for sustainability. In terms of financial factors, equity ratio shows the soundness of management, which has positive effects on the enforcement of marketing in the steady state economy. Moreover, ROE measures a company’s profitability by revealing how much profit a company generates with the money which its shareholders have invested. Finally, payout ratio provides valuable insight into a company’s dividend policy. Higher payout ratio indicates that the company is sharing more of its earnings with the shareholders. Implications The findings of this research contribute to the academics by providing a new framework for the marketing in the steady state economy. Further research can empirically test the proposed model in various countries to investigate if this framework is culturally specific to Japan or not. This research also provides practical implications for managers. For sustainable business and better society, companies should keep their eyes on the five elements presented in our research. Thus we can take the very first step for the marketing in the steady state economy.

economic growth and revenue / profit expansion, we will end up with overconsumption and wastes, bringing serious damage to our planet (Kotler, 2015). He advocated the transition from the growth-oriented economy to the steady-state economy. This research explores marketing in such steady-state economy. Researchers have put efforts in developing theories in related concepts such as social marketing (e.g., Kotler & Zaltman, 1971) and corporate social responsibility (CSR; see Peloza & Shang, 2011 for a review). Inoue and Kent (2014) developed a conceptual framework that explains antecedents and consequences of corporate social marketing. However, their research, as well as those on CSR, has not addressed marketing in steady-state economy. Thus, we attempt to fill this research gap by developing propositions. We conducted multiple case studies (Eisenhardt, 1989; Yin 2014). Based on theoretical sampling, three firms were selected from different industries (food, alcohol, and furniture) with different technologies, located in different areas in Japan (Tokyo, Nagano, and Kagoshima). We collected primary and secondary data, and conducted interviews. In spite of the differences, the three firms run business similarly. First, they pursue a sustainable growth and not a rapid growth. Second, doing what is good for society is a part of their business goal and not CSR. Finally, they choose inefficiency than lowering the product quality.economy are developed: P1. Selling high quality products at profitable but reasonable price enhances firm’s credibility, which in turn improves the probability of firm’s long-term survival. P2. Limiting distribution channel allows firm to avoid price competition and set reasonable pricing, which in turn improves the probability of firm’s long-term survival. P3. Marketing mix of high quality product, reasonable pricing, and limited distribution channel generates positive word-of-mouth, allowing firm to save promotion costs. P4. Prosocial behavior in procurement increases the brand loyalty, which in turn improves the probability of firm’s long-term survival. P5. Portfolio of business-to-business and business-to-consumers businesses allows stable management and building strong brand. Further research is needed to develop these propositions into hypotheses and empirically test them with large samples. The authors hope that this research will be the first step for “steadiness-oriented marketing.”

막이나 케이블 요소는 재료의 경량성과 유연성으로 인해 여타의 철강이나 콘크리트와는 다른 대공간 구조물이다. 막이나 케이블 요소가 유연성을 가지는 이유는 휨 강성이 인장 강성에 비해 무시할 수 있을 정도로 아주 작기 때문이다. 이러한 막이나 케이블 구조물이 강성 구조물과 다른 가장 큰 특징중의 하나는 전체적인 구조물을 구성하는 부재들에 의하여 발생하게 되는 변위보다는 구조물 자체의 변형이 더 지배적이다. 다시 말하면, 이러한 구조물은 변형없이 대변위를 발생시킨다는 것이다. 본 논문에서는 이러한 변위를 '불신장 변위(inextensible displacement)'라고 부른다. 그리고 불신장 변위가 발생하는 구조물을 '불안정 구조물'이라고 정의한다. 따라서, 이러한 불안정한 구조물을 안정한 구조물의 형태로 이행하기 위한 과정이 필요하고 이러한 과정을 '불안정 구조물의 안정화 이행과정'이라고 한다. 기존에는 준정적인 해석을 통해 구조물의 초기 불안정 형태를 안정화 시켰다. 여기서 '준정적'이라고 하는 것은 시간에 따라 속도는 일정하고 가속도는 존재하지 않는다는 것이다. 더 나아가 로봇공학, 생물역학 그리고 대공간 구조물에의 적용을 위하여 이러한 종류의 구조물을 동적인 메카니즘하에서 구속되어 있는 다수요소로써 모델화하는 연구가 진행되어졌다. 본 논문에서는 불안정 구조물의 동적 해석을 위한 정식화 과정중에서 수치적인 방법을 제안하였다. 제안된 방법은 기존의 동적 해석기법과는 달리 본 논문에서는 차원을 저감시키는 수치해석기법으로써 RREF를 이용하였고, 불신장 변위모드를 추출함으로써 불안정 구조물의 동적 거동을 추적하였다. 본 논문에서 제안하는 수치해석기법을 이용하면 불안정 구조물의 효율적인 동적 해석이 가능하다는 것을 알 수 있었고, 나아가서 이러한 방법은 트러스 구조물 뿐만 아니라, 케이블이나 막 구조, 케이블과 막이 결합된 형태인 복합구조물에도 그 응용이 가능하리라고 사료된다.

목재투습성에 관하여 다음과 같은 결과가 밝혀졌다. 1) 시편두께 0mm에 외삽한 투습저항값이 정(正)이므로 목재표면에서의 수분전달현상을 고려함이 인정되었다. 2) 목재내부의 함수율분포는 함수율 9%를 경계로 두 개의 직선으로 나타났다. 또 시편양측의 공기중 평형함수율이 9%이상일 때는 한 개의 직선으로 나타났다. 수분확산계수는 함수율 9%를 경계로 두 개의 일정한 값을 가지며, 이 값들은 오직 함수율에만 관계한다. 4) 수분이동량은 목재내의 함수율구배에 의존한다. 4) 목재의 수분전달계수는 시편두께에 의존하였다. 이 현상의 기구에 대해서는 아직 알 수 없다.

복잡한 수심을 가진 연안해역에서 조석, 바람과 파랑에 의해 발생된 흐름의 영향까지를 고려한 파랑모델의 도입은 대부분의 해안공학 설계나 방재 문제에 매우 중요한 요소이다. 근해역에서 수심변화에 의한 굴절 및 천수효과, 흐름에 의해 유발되는 굴절효과, 파형경사에 따를 쇄파, 회절, 바람에 의한 파의 성장, 파랑 상호간의 간섭, 파랑과 흐름의 상호 간섭 및 에너지 재분포 등을 다룰 수 있다는 점에서 정상상태 스펙트럼 모델의 현장 전용은 지금까지 여러 모델이 다루지 못한 부분을 해소하게 될 것이다. 본 연구에서는 부산 신항만 건설이 이루어지고 있는 가덕인접의 넓은 수역에 대해 파랑의 변환과정을 보다 합리적으로 해석하기 위해 스펙트럼 모델을 적용하고 기존의 모델 결과와 비교 분석하는 것을 골자로 하고 있다. 이러한 시도가 가까운 장래에 항만설계 및 방재시스템 분야에서 보다 안전하고 널리 스펙트럼 모델을 적용하게 하는 계기가 되도록 의도하였다.

난지도 매립지는 주변에 오염차감시설을 설치하지 않은 불량매립지로서, 매립지내의 수위가 높고 지층의 심도가 높다. 따라서, 본 연구에서는 층상대수층을 이루고 있는 난지도 매립지에서 정상상태의 지하수 흐름에 대한 용질의 이용을 HST-3D모형을 사용하여 해석하고, 용존오염물의 농도변화를 예측하였다. 모형의 적용 결과, 지하수의 흐름은 제1매립지와 제2매립지를 중심으로 방사상으로 진행되고 있으며, 한강으로 다량이 유출되고 있는 것으로 나타났다. 난지도 매립지