Soldering 6061 Al by Sn9Zn Coating With/Without Two Step Ultrasonic Effect

Hao Hong,Ding Min 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.8

The work described the effect of soldering 6061 Al by soldering coating with/without two step ultrasonic process, basedon Sn9Zn alloy prepared by high frequency melting and rapid solidification. The microstructure, interfacial morphology,shear strength and mechanical morphology of 6061 aluminum alloy soldered joints were compared and analyzed. Theresults showed that the ultrasonic soldering with coating by two step ultrasonic process technology could greatly improvethe morphology of the joints and refine the grain size. The solder layer with larger scallop shape was transformed into adense fine structure. After two step ultrasonic effect, the width of the joint was about 28% higher than that under the firstultrasonic process. The Zn-rich phase length decreased from an average of 90 μm to an average of 25 μm, about 27% of theoriginal length. The refinement of solder seam was related to the additional dissolved Al and IMC particles. The refinementmechanism was mainly sono-crystallization + sono-fragmentation with two step ultrasonic effect, which was different fromthe refinement mechanisms of the first ultrasonic effect with sono-crystallization. At the same time, the shear strength of6061 aluminum alloy joints bonded at low temperature could reach 230 MPa by two step ultrasonic effect. Compared withthe ultrasonic soldering with coating, the hardness and maximum strength were improved by 14.5% and 28%, respectively.

Low Temperature Soldering 6061 Aluminum Alloys by Using the Synthesized Sn9Zn Nano-Amorphous Particles

Hao Hong,Ding Min 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.8

To meet the growing demand of technologies of high performance electronics, nano-solders have been widely developed. In the present study, Sn-Zn nano-amorphous particles with core–shell structure were synthesized by a chemical reductionmethod with NaBH4 as reduction agent and Polyvinylpyrrolidone (PVP) as a stabilizer. The size distribution and thermalbehaviour of the as-synthesized nano-particles were controlled by the amount of PVP, whose concentration ranged from 3to 30 wt%. And the change was comparatively confirmed by TEM, DSC and XRD analysis. The results revealed that PVPconcentrations can not only regulate and control the size distribution of the nano-particles and the melting point, whichcould also change the ratio of amorphous shell to crystalline core in nanostructures. In addition, sintering behavior of thisnano-solder soldering 6061 aluminum alloys and its corresponding mechanical properties were evaluated based on SEM,XRD and the shear tests. The results turned out the best bonding quality was obtained under the condition of the content ofPVP is 10 wt%. The obtained shear strength was as high as 17.6 MPa, and the elemental composition of the thinner IMClayer was Al2Zn3,which revealed a good solderability property. The above analysis provided a new insight into the effects ofPVP content on the interfacial reaction mechanism. This bonding technology was suitable for the electronic devices bondedat low temperature.

试论笹川种郎《支那文学史》译本《历朝文学史》的动态经典作用(下)

郝蕊(Hao,Rui) 조선대학교 국제문화연구원 2016 국제문화연구 Vol.9 No.1

According to the polysystem theory of Itamar Even-Zohar, a conclusion can be drawn that the introduction of the history of Chinese literature in 20th century which was a completely new conception to Chinese had transformed Chinese literature study from convention to contemporary, by observing the environment in which the translation of Sasakawa Taneo’s original work A History of Chinese Literature was published, such as the translation selection, characteristics of translator’s subjectivity, publishing activities, etc. Among those several works about history of Chinese literature written by foreign experts in early times, the Japanese ones were considered as the most influential on China.The Development of Literature, one of them, neither the best nor the earliest, played a Dynamic Canon role at that time when the study of the history of Chinese literature was just beginning, owing to its timely presence and its particular translation and publication environment. Keywords: history of Chinese literature, Sasakawa Taneo, The Development of Literature translation and publishing, Dynamic Canon

The Antecedent Factors Influencing Long-term Relationship Orientation in Overseas B2B Markets

Hao Zhang(Hao Zhang),Yeung-Kurn Park(Yeung-Kurn Park),Xueting Zhang(Xueting Zhang) 한국무역연구원 2022 무역연구 Vol.18 No.6

Purpose – Based on the past overseas business experiences of China Business to Business (B2B) enterprises, this study focuses on the influence of relationship marketing factors on the long-term relationship orientation of trading partners. First, this study discusses whether the relationship marketing factors in B2B environment-information sharing, customer orientation and interdependence will lead to the relationship satisfaction of enterprise customers. Then, it discusses whether relationship satisfaction leads to long-term relationship orientation of corporate customers. Finally, the mediating role of relationship satisfaction between relationship marketing factors and long-term relationship orientation is analyzed. Design/Methodology/Approach – The data were collected through questionnaires, and the persons in charge of sales and purchases of 350 B2B enterprises in China were investigated. Finally, 296 valid questionnaires were used for research and analysis. Findings – The analysis results of this study are summarized as follows: First, this study reveals the positive influence of relationship marketing factors such as information sharing, customer orientation and interdependence on relationship satisfaction. Second, relationship satisfaction is confirmed to have a positive impact on long-term relationship orientation. Third, the analysis of the mediating effect of relationship satisfaction shows that “relationship marketing factors lead to long-term relationship orientation through relationship satisfaction. Research Implications – This study confirms that information sharing, customer orientation, and interdependence are key factors that shape relationship satisfaction. Managers of B2B companies should have a clear understanding of relationship marketing. All policies and behaviors of an enterprise must be guided by the interests and needs of enterprise customers and ran through the entire process of production and marketing. Enterprises should strengthen two-way communication with corporate customers to understand each other’s needs and gradually form interdependent relationships with corporate customers. They should provide customers with comprehensive and thoughtful services, so that they can have a sense of identity and belonging to the enterprise, and then achieve relationship satisfaction and be willing to maintain a long-term relationship.

환율과 주가의 상호관계에 대한 연구: 두 차례 금융위기 이벤트를 중심으로 원/달러 환율과 KOSPI종합지수에 대한 실증분석

( Hao Hao Li ),( Tae Joong Kim ) 국제지역학회 2013 국제지역학회 춘계학술대회 Vol.2013 No.-

본 연구는 환율과 주가 두 변수간의 상호영향을 분석함에 있어서 연구기간이 일반적인, 비교적 긴 기간에만 집중되고 있는 대부분의 기존연구와 달리 이벤트 중심으로 두변수간의 관계를 분석하였다. 금융시장이 전면적으로 개방된 시점인 1997년부터의 KOSPI지수와 원/달러 명목환율의 일별자료를 이용하여 두 시계열변수간의 상관관계와 선후행관계에 대하여 알아보았다. 분석결과, 첫째, 안정성검정에 있어서 ADF 단위근검정 방법을 사용하였는데 이벤트 발생 후 1개월 기간을 제외한 나머지 기간에는 1차 차분을 통하여 불안정성이 제거 되는데, 이는 이벤트 발생 후 1개월 이내에는 시계열이 상대적으로 더욱 불안전하다고 해석할 수 있다. 둘째, 그랜저 인과관계 분석을 진행하여 선후행관계에 대하여 분석한 결과, 이벤트 발생 후 1년 정도의 기간에 대체적으로 선후행관계가 비교적 선명하게 나타났다. 글로벌 금융위기일 경우에는 이벤트 발생 후 8개월 기간의 여러 기간에 대하여 일관되게 환율이 주가를 선도하는 관계가, 외환위기일 경우에는 이벤트 발생 후 1년 기간에 미미한 피드백관계가 나타났다. 셋째, 교차상관관계 분석은 그랜저 인과관계 분석결과를 강력하게 지지해주고 있다. 글로벌금융위기의 경우에는 환율이 선도할 경우 선명한 정의 상관관계를 나타내어 전통적 접근을 따르고 있으나 외환위기의 경우에는 그 관계가 미미하게 나타났다. 또한 대체로 이벤트 발생 시점에서 가까운 기간일수록 두 시계열변수간의 상관관계가 더욱 선명하게 나타났다. We analyzes the interaction between Exchange rates and stock prices, focusing on a relatively short period of time and events, unlike most of the previous studies analyzed the long relationship between two variables. First, in the ADF unit root test, except for the period of one month period, the primary difference is removed through the instability. Second, the Granger causality analysis proceeds for the analysis of precedence relations, event for a period of one year after the precedence relations. If the global financial crisis period of 8months after the occurrence of the event leading to consistently exchange relationship, when the crisis in the 1-year period after the occurrence of an event related feedback was minimal. Third, the cross-correlation analysis strongly supported Granger causality. In the case of the global financial crisis, when the exchange rate leading a clear positive correlation follows the traditional approach, but in the case of the financial crisis that the relationship was insignificant. In addition, more short-term correlation were more clearly.

The Distribution of Information through Online Meeting after COVID-19: Examining the Effect of Past Behavior

Van Hao HOANG(Van Hao HOANG ),Van Vien VU(Van Vien VU ),Quang Truong NGO(Quang Truong NGO ) 한국유통과학회 2023 유통과학연구 Vol.21 No.8

Purpose: Online meeting is chosen instead of face-to-face conferences as a solution that ensures both effectiveness and legality during times of strong epidemic outbreaks. In the current period, managers can have different types of meeting options for information distribution. This study has examined the effect of past behavior on the managers’ intention of organizing online meetings. Research design, data and methodology: Data were collected from a survey with 475 managers and put into SmartPLS 4.0 for analysis. Partial least squares structural equation modeling (PLS-SEM) was employed to test relationships in the research model. Results: The findings indicated that past behavior plays the most critical role in explaining the organizing online meeting intention of managers, followed by attitude and subjective norms. Meanwhile, the perceived behavioral control factor has absolutely no effect on intention in the context of this study. Notably, attitude and subjective norms also remarkably mediated the impact of past behavior on managers’ intention. Conclusions: This study has added to the understanding of the meeting organization behavior of managers. Even if the epidemic is under control, the administrators should still organize some meetings in the form of online because it will affect the social perceptions of future behavior and behavioral intention.

The Impact of Public Pension on Chinese Household Consumption

Ya-Hao LI(Ya-Hao LI),Fan YANG(Fan YANG),Shuang ZHANG(Shuang ZHANG) 한국웰빙융합학회 2024 웰빙융합연구 Vol.7 No.1

Purpose: The improvement of the social security system can greatly affect residents' future uncertainty, and it is important to study the relationship between public pensions and household consumption. Research design, data and methodology: Using the 2018 China Household Panel Survey (CFPS) data, the instrumental variable method is used to analyze the impact of pension insurance on urban residents' consumption. Results: The results of the study show that there are differences in the impact of three different pension insurance systems on household consumption. The pension insurance for public sector significantly boosts household consumption, and having a pension insurance for public sector can increase household consumption by 7.7%. The pension insurance for enterprise employee will reduce household consumption, but this is only significant for urban households. The pension insurance for urban and rural residents has a negative impact on household consumption. For the 16- to 39-year-old group, having a pension insurance for urban and rural residents will reduce household consumption by 5.7%. At the same time, household income, assets, scale, and education level will positively stimulate household consumption. Conclusions: The study reveals varying impacts among different pension types, highlighting the need for optimizing social security schemes to incentivize higher consumption rates.

Chemical profile and antimicrobial activity of Ocimum gratissimum L. essential oil from Dak Lak province, Vietnam

Pham My Hao(Pham My Hao ),Le Pham Tan Quoc(Le Pham Tan Quoc ) (사)한국식물생명공학회 2024 JOURNAL OF PLANT BIOTECHNOLOGY Vol.51 No.1

Attenuation effects of perforated plates with heterogeneously distributed holes on combustion instability in a spray flame combustor

Hao Zhou,Zihua Liu,Hao Fang,Chengfei Tao,Mingxi Zhou,Liubin Hu 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.11

Perforated plates have been widely used in combustors to attenuate harmful sounds. In this study, the acoustic absorption capability of plates with heterogeneously distributed holes under bias flow was evaluated in an impedance tube, and the sound attenuation effect of each plate located in the liquid fuel combustor inlet section was experimentally studied. The perforated plate with heterogeneously distributed large holes showed the best control effect under the designed experimental conditions. After control, the peak dynamic pressure in the chamber and plenum decreased by 90 % and 75 %, respectively, and the reduction in the heat release fluctuation was 60 %. When the primary air flow rate deviated from the optimal value, the plate with large holes still reduced the pressure amplitude in the chamber by approximately 70 %. It was also found that installing the perforated plate with a back cavity had the dual effect of gaining and damping combustion instability.

Electronic effects on protective mechanism of electropolymerized coatings based on N-substituted aniline derivatives for mild steel in saline solution

Hao Liu,Baomin Fan,Zining Liu,Xiaoqi Zhao,Biao Yang,Xingwen Zheng,Hua Hao 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.106 No.-

Polyaniline (PANI), poly(N-methylaniline) (PNMA) and poly(N-formylanilide) (PNFA) coatings were fabricatedover mild steel via chronoamperometric strategy in oxalate electrolyte. Scanning electron microscope(SEM), attenuated total reflection infrared spectroscopy (ATR-IR) and X-ray photoelectronspectroscopy (XPS) evidenced the polymerization of monomers. Anticorrosive effects of PANI, PNMAand PNFA coatings for steel substrate were evaluated during long-term immersion in 3.5% NaCl solutionby potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and frequency modulation(EFM). Morphological variation for coated specimens before and after immersion in NaCl solutionwas also monitored by SEM and atomic force microscope (AFM). Differentiated protection capability wereobserved for three coatings following the sequence of PNFA > PNMA > PANI. Through electrochemical andinterfacial analyses, electroactivity and physical barrier were ascertained as the critical factors, especiallythe former one, in the long-term protection capacity. Electroactivity was distinguished by the elevatedapparent current density from non-destructive EFM measurements. Furthermore, electron-donationand -withdrawal effects of N-substituents played an essential role in coating electroactivity. In detail,N-substituents improved the anodic protection and physical barrier of PNMA and PNFA coatings. Particularly, formyl with electron-withdrawal effect reinforced the anodic protection and thus the superiorthe anticorrosion efficiency of PNFA for underlying steel.