• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.6
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• pp.15-20
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• 2015

Bit patterned media (BPM) is a high capacity storage system and has attracted a great deal of attention as next generation data storage. When BPM is made with high density, the space between the islands narrows, because BPM records one bit in an island. For this reason, BPM has inter-symbol interference in all directions, unlike in current storage systems where it is in only one direction. In this paper, we propose an equation for compensating two-dimensional ISI. We conduct experiments on track misregistration. When using the proposed inter-symbol interference preprocessing, the BER performance is improved, regardless of the amount of track misregistration.

• Korean Journal of Materials Research
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• v.7 no.5
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• pp.444-450
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• 1997

기계적합금화 한 AI-Ti합금의 상온 및 고온 인장강도는 25at.% Ti을 Ce으로 치환함에 따라 증가하였다. 그러나 25at.% 이상의 Ce첨가는 합금의 인장강도를 감소시켰다. 이는 Ce이 적은 고용도 효과에 의해 금속간화합물의 초대화를 억제하여 합금의 강도를 증가시키지만 다량 첨가시에는 Ti에 비해 무거운 원자량으로 인해 분산상의 부피분율을 감소시켜 합금의 강도가 오히려 저하시킨 것으로 생각된다. Ce의 첨가는 40$0^{\circ}C$와 51$0^{\circ}C$에서 합금의 열저안정성을 향상시키는 것으로 나타났다. 300-51$0^{\circ}C$ 온도범위에서 측정된 AI-8wt.%(Ti+Ce)합금의 변형에 필요한 활성화에너지는 AI의 자기확산에 필요한 에너지 (142kJ/mode)의 1.3-1.9배로 나타났다. 이로부터 AI-Ti-Ce 합금의 고온 변형은 Orowan기구에 의한 것을 생각된다.

• International Area Studies Review
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• v.13 no.2
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• pp.145-167
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• 2009

This study aims to examine attitudes of Korean workers towards foreign workers and predictors of their attitudes. The data for this study come from a survey conducted among 500 Korean workers employed at the companies which also hire foreign workers in Gyeonggi and Incheon areas. The findings reveal that a little more than half of Korean workers agree to give foreign workers the same labor rights as Korean workers and to allow them to bring their family members into Korea while a little less than half of them do not agree to grant residentship or citizenship to foreign workers. Attitudes towards foreign workers tend to be favorable with increase in perception of multiculturalism, period of working experience with foreign workers and education, and with decrease in feeling of threat from foreign workers.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.1
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• pp.13-28
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• 2022

Korean Government Budget Supports for startups have been spiked and resulted in increasing the number and scaling up Startup Accelerating managers. It have skyrocketed the strong demand for their qualified roles. However, unclear role description and gap between required role and their capability have discouraged startup manager's self-efficacy resulted in declining their full commitment and causing poor role performance. The focus of this research falls on empirical analysis to the effect of startup accelerating manager's capability characteristics on their full commitment and performance to start-up support groups. This research is expected to deliver diverse policy alternatives to build up manager's core competencies to accelerate their self-efficacy leading their full role commitments and finally pushing up policy performance. In addition, this research will found more strong literature review for the following researches in this emerging fields. This research is brought four highlighting results with respect to four research problems. First, it propose proper concept of startup accelerating manager based upon its legal entitlement. Second, it drive required core competencies of manager for successful their accountability. Third, it analyze the unique features of startup accelerating manger's capabilities against business incubation manger. Fourth, it empirically analyze in coming with government startup funding, the effect of self-efficacy including employment status, job environment, etc. on their organizational commitment and job performance. This research reveal the required unique core competencies of manger into founder sourcing ability, project managing ability, startup proving and pivoting ability, consulting ability for successful investment raising. As of this empirical research results, First, manager's ability have positively effect on their job performance, full commitment, and self-efficacy. Second, self-efficacy have a mediating effect on manager's ability, job performance, full commitment. This research derive key policy implication of requiring to build up more accelerating ability, of manager from the basics to advance level by customized and algorithm based traing program. This accelerating ability buildup program will not only surge self-efficacy of manger resulting in making full commitment and better job performance, but also devote to categorizing the unique new feature and position of manger as seed investment and supporter.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.4
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• pp.219-232
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• 2022

Empirical studies on entrepreneurial intentions have been conducted from various perspectives over the past few decades. The unemployment rate has increased as the global economy stagnates in the aftermath of the COVID-19 pandemic, and entrepreneurship is emerging as an alternative to job creation. Although numerous antecedent variables have positive effects on entrepreneurial intention, this study focuses on entrepreneurial self-efficacy as an individual factor and the entrepreneur's family background as an environmental factor. This study analyzed the survey results of 300 global respondents through the online survey platform Prolific. The respondents were screened by asking a question about having had entrepreneurial education. Since the effects of entrepreneurial self-efficacy on entrepreneurial intention have been proved in numerous domestic studies, this study aims to generalize these results by investigating global samples. The moderated mediation analysis was performed using PROCESS to verify the research hypotheses. This research investigated the effect of entrepreneurial knowledge acquisition on entrepreneurial intention via entrepreneurial self-efficacy and the moderated mediation effect of the family background of entrepreneurs. The results of this study are summarized as follows. First, acquisition of entrepreneurial knowledge had a positive effect on entrepreneurial intention. Second, entrepreneurial self-efficacy mediated the relationship between entrepreneurship knowledge acquisition and entrepreneurial intention. Third, the entrepreneurship family background moderated this relationship. Specifically, when the family entrepreneurship background is strong (vs. weak), the positive effect of entrepreneurial knowledge acquisition on entrepreneurial intention via entrepreneurial self-efficacy significantly increased. The implications of this study are as follows. First, in the process of preparing for a own business, entrepreneurial education is a necessary condition to improve the entrepreneurial intention. Second, the higher the level of acquisition of entrepreneurial knowledge, the more positive attitudes toward entrepreneurial intention can be induced. Third, strong family background of entrepreneurship further promotes entrepreneurship intention by increasing entrepreneurial self-efficacy. In conclusion, in order to revitalize entrepreneurship, it is important to provide various entrepreneurial education programs. These educational programs will be able to improve entrepreneurial self-efficacy by providing more opportunities for students to acquire entrepreneurial knowledge, and thereby promote entrepreneurial intention. In addition, it is important to develop and provide advanced educational curriculum for those who have start-up business experiences in their families.

• Korean Journal of Biological Psychiatry
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• v.24 no.3
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• pp.95-109
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• 2017

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive neuromodulation technique which can change cortical excitability in targeted area by producing magnetic field pulses with an electromagnetic coil. rTMS treatment has been used to treat various neuropsychiatric disorders including depression. In this review, we evaluate the literature on rTMS for depression by assessing its efficacy on different subtypes of depression and different technical parameters. In particular, we focus on the results of randomized clinical trials and meta-analyses for depression after the US Food and Drug Administration approval in 2008, which acknowledged its efficacy and acceptability. We also review the new forms of rTMS therapy including deep TMS, theta-burst stimulation, and magnetic seizure therapy (MST) that have been under recent investigation. High frequency rTMS over left dorsolateral prefrontal cortex (DLPFC), low frequency rTMS over right DLPFC, or bilateral rTMS is shown to be effective and acceptable in treatment for patients with non-psychotic, unipolar depression either as monotherapy or adjuvant. Deep TMS, theta-burst stimulation and MST are promising new TMS techniques which warrant further research.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3587-3598
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• 2014

This study analyzed the efficiency of a program designed for enforcing the job-seeking ability to overcome the career-barriers as well as the effect of the job-seeking efficacy toward the job-maintaining willingness of the disabled. For this research, the job-seeking ability enforcement program, which was started by the Korea Employment Agency for the Disabled, was executed towards the 86 disabled by 7 sessions, which has been operated 6 hours a day for 4 days per week from December in 2012 to November in 2013. The survey for the study was taken twice with the same questionnaire toward the same object; one was a pre-survey that has been done before operating the program and the other was a pro-survey that was done after operating the program. The data was analyzed to obtain the 4 variables of job-seeking efficacy to overcome the career-barriers, which were self-efficacy, job-seeking skill, interpersonal relationship skill and job-information exploration and the 5th variable, job-maintaining willingness. The study findings were as follows. Firstly, the program efficiency was significant in interpersonal relationship skill and job-information exploration, while not significant in self-efficacy and job-seeking skill. Secondly, the self-efficacy and interpersonal relationship skill among the job-seeking efficacy to overcome career-barriers positively affects the job-maintaining willingness.

• Journal of the Korean Magnetics Society
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• v.4 no.3
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• pp.226-232
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• 1994

Rapidly solidified $SmFe_{7+x}M_{x}(M=Mo,\;V,\;Ti)$ compound were found to crystallize in the ${Sm(Fe,\;M)}_{7}$ based stable magnetic phase by introducing a second transition element into the Sm-Fe binary system. The ${Sm(Fe,\;M)}_{7}$ phase exhibits the highest Curie temperatuer ($T_{c}=355^{\circ}C$) ever Known in the Sm-Fe magnetic systems with a quite high intrinsic coercivity($_{i}H_{c}=3~6\;kOe $). The ${Sm(Fe,\;M)}_{7}$ phase remains stable even after annealing if once form during the rapid solidification. The primary reason for the high coercive force is due to the fine grain size($2000~8000\;{\AA}$)of the magnetic ${Sm(Fe,\;M)}_{7}$ matrix phase, and the enhanced Curie temperature is attributed to the extended solid-solubility of the additive transition elements in Fe matrix, which leads to volume expansion of the ${Sm(Fe,\;M)}_{7}$ cell causing an enhanced coupling constant of Fe atoms.

• Journal of the Korean Electrochemical Society
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• v.2 no.2
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• pp.88-92
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• 1999

The apparent density. self-separation of the electrode composite from current collector in the electrolyte solution and specific resistance of electronic conduction of the electrode composite were examined by the variation of content of conductive material such as graphitic and black carbons in $LiCoO_2$ composite electrode for lithium ion battery. Increasing the content of conductive material, the apparent density of Lico02 composite electrode was decreased and that of $LiCoO_2$ in composite electrode was only rapidly decreased compared to that of composite. $LiCoO_2$ composite electrodes containing more than 4.1 weight percent of super s black as a conductive material were seU-separated by the immersion into 1 mol/I $LiPF_6$ in propylene carbonate and diethyl carbonate (1:1 volume ratio). Specific resistances related to the electronic conduction of composite electrode were decreased by the increasing the content i)f conductive material. Specific resistance of the composite electrode including $2\~3\%w/w$ of super s black as conductive material was similar to that of $12\%w/w$ of Lonza KS6. In the range of this study, super s black as conductive material is better than Lonza KS6 on battery capacity because of apparent density of $LiCoO_2$ in electrode composite including super s black is higher than that of Lonza KS6.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2002.11a
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• pp.63-63
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• 2002

현재 기계적 합금화법에서는 주로 합금을 구성하는 성분원소 분말을 불활성분위기에서 볼밀처리 함으로써 함금화를 시키거나 모합금에 산화물을 분산시켜 복합화시키는 공정을 통하여 각종 화합물, 비정질상 및 과포화고용체등의 준안정상의 합성 뿐만이 아니라 초미세조직의 생성에 관한 폭 넓은 분야의 연구가 행하여지고 있다. 한편 MA에서는 볼멀처리중 기계적 에너지의 투여에 의하여 실제 반응온도보다 낮은 온도에서 발생하는 특이한 화학반응 즉 Mechanochemical 반응을 일으키 기도 한다. 본 연구에서는 헤마타이트($Fe_20_3$)와 금속윈소인 Ti의 MA처리에 의하여 고상환원반응 을 유기시켜 $Fe-TiO_2$계 nanocomposite 분말재료를 제조하고자 한다. 특히 MA 공정에 있어서 자기 물성의 변화와 X선 회절을 통하여 고상환원반응에 의한 복합분말의 생성과정을 조사하였다. 출발원료는 $Fe_20_3$(고순도화학제,99.9%, 평균입경 0.1$\mu\textrm{m}$)와 금속원소인 Ti(99.9%, 명균업경 150$\mu\textrm{m}$)을 몰비 2:3의 조성이 되도록 하여 MA를 실시하였다. 볼멀은 고에너지 유성형 볼밀장치(독일 제, Fritsch P-5)를 이용하였으며 진공치환형 용기에 원료분말을 장입하여 2회정도 진공배기한 후 아르곤 가스를 충전하여 볼밀을 행하였다. 얻어진 분말시료에 대하여 x-선 회절장치, 전자현미경 (SEM) 및 진동시료형자력계(VSM)를 통하여 결정구조, 미셰조직 빛 자기특성을 조사하였다. $Fe_2O_3-Ti$ 혼합분말의 MA처리 에 의하여 초기단계부터 환원반응과 함께 $Fe_3TIO_{lO}$ 중간상이 관찰 되었으나 30hrs의 MA처리 후 Fe와 산화물 $TiO_2$로 모두 환원되어 $Fe-TiO_2$계 나노복합분말이 얻어짐을 알 수 있었다. 이 때 X션 회절피크의 line broadening으로부터 복합분말의 Fe 명균 결정립 크기는 24nm로 초미세 결정럽의 분말합금이었다. 포화자화값은 볼밀처리에 따라 점점 증가하여 MA 30시간에는 20.3emu/g로 포화됨을 알 수 있었다. 또한 보자력 Hc는 MA초기단계에 350e로 매우 낮으나 30시간 후에는 Hc값이 2600e로 매우 큰 값을 나타내었다. 이것은 환원반응결과 초기에 생성된 Fe의 결정립이 비교적 크고 결정결함이 적으나 볼밀처리를 30시간까지 행하면 Fe 결정렵의 미세화 빛 strain 증가로 magnetic hardening이 일어나기 때문인 것으로 사료된다.