Headspace 가스크로마토그라피를 利用한 食用油 酸化進行度의 評價方法

전호남 서울대학교 대학원 1989 국내박사

韓國産 옥수수의 脂質成分에 關한硏究

전호남 서울大學校 大學院 1983 국내석사

클러스터링을 이용한 학습자 의사소통 능력신장방안

전호남 강릉대학교 교육대학원 2007 국내석사

The purpose of this study is to investigate how to improve spoken English competence of the studdents who are beginners in listening and speaking English throughout studying clustering. It is pointed out that English conversation classes studying grammar intensively is not helpful to develop the spoken English competence of students lacking in a basic knowledge of English. So, to let them speak and listen to materials well during the class, I have designed a useful group of words and phrases to use to communicate with each other in English fluently. This is known as clustering. This clustering is made up of short and important expressions used to make complete sentences. Therefore, in students case they can use them anywhere, anytime when they want to communicate in English by using them. Because it is too simple to memorize. Furthermore, the spoken English competence can effectively be improved by making students practice listening and speaking part in English on the foundation of the clustering acquired. To accomplish this, 60 second-year students of a boy's middle school in Gangneung were classified into two groups (experimental and comparative) The experimental group was carried out for 2 class-hours a week for 6 months to a group of 30 students. they were given some specific teaching techniques which can improve speaking skills instead of using translation and explaining grammar in the speaking part was given to the comparative class. The following hypothesis were tested 1) Some specific speaking activities by using clustering could improve interest and self-confidence of the students. 2) The experimental group with speaking activities which were made based on the situational clustering could get better marks on the speaking test than the comparative group. Acquiring clustering knowledge of English is indispensible to improve listening and speaking part. It means that you can learn two distinguished materials at the same time. To build up word power, the knowledge of the contextual information, clustering connected with a word's meaning must be acquired. The knowledge of word order, sentence pattern and grammar is required in order to produce English sentences by oneself. It is not an inevitable truth to study English, but, in this case, the story of that theory has different notions. It is that everyone can improve their two different functions out of four throughout studying clustering at the same time. The way to acquire from the foundation of communicative competence is memorizing a simple and easy sentence such as clustering. More importantly, the sentences memorized must be internalized so that may take firm roots in the speech and listening nerve. Studying clustering is the only way to internalize them. It is suggested that to practice memorizing the simple sentences or phrases, students can be drilled students in speaking and listening English. Everyone can make the clustering as they wish, but, it should be short, meaningful, and correct as well. Studying clustering can be one of the most popular alternative way if it is used correctly. The following teaching techniques were practiced: task-based tasks, internet, visual aids, dialogue practice, role-play, riddle games. For the experimental analysis, a questionnaire for the interest and self-confidence in speaking was administered to the experimental group before and after the experiment to test the first hypothesis, and English grades from two speaking tests were used to test the second. The results were as follows. 1) The percentage of student's interest and self-confidence in speaking English went up meaningfully. 2) The way which is using clustering between the pre - and post-experimental speaking tests shows that some specific speaking activities did have some effects on the student's speaking grades. The gap between the experimental class and the comparative one was statistically meaningful. In conclusion, educators should do their best to improve their student's speaking ability by giving them a chance to perform a more communicative activity by using the clustering approach.

배터리 자동교체형 모바일 로봇 및 스테이션 개발

전호남 경상국립대학교 대학원 2024 국내박사

In this paper, we have designed and manufactured a mobile robot and an automatic battery replacement station to address the battery charging time issue of mobile robots. The automatic battery replacement mobile robot is comprised of two motors, four casters, and a battery case that allows for the insertion and removal of batteries. The automatic battery replacement station is composed of a holder capable of charging and moving two battery packs. To replace the mobile robot's battery, the robot docks at the automatic battery replacement station, and the station's battery holder removes the discharged battery while inserting the charged battery into the robot's battery case. The mechanical components of the automatic battery replacement mobile robot and the automatic replacement station were designed through structural analysis using software, and the designed robot and station were manufactured. An experiment on the battery replacement characteristics of the manufactured automatic battery-replaceable mobile robot and station was conducted. The results of the experiment indicate that the battery replacement time is within 25 seconds, and the docking accuracy error of the mobile robot is 10mm. Additionally, the driving characteristic test of the mobile robot, with a payload of 100 kg, achieved speeds over 2 km/h. The autonomous driving characteristic test in a given route within an indoor space was completed without collisions. Therefore, it is anticipated that the battery-automatic-replaceable mobile robot and battery-automatic-replacement system developed in this paper will be beneficial for various service robots, such as those used in quarantine and delivery, which operate continuously for extended periods.

리튬이온 배터리의 수명개선을 위한 병렬접속회로에 대한 연구

전호남 경상대학교 융합과학기술대학원 2021 국내석사

본 논문에서는 리튬이온 혹은 리튬폴리머 배터리셀로 구성된 배터리팩을 병렬접속회로로 설계할 경우에 배터리셀의 전류부담을 경감시켜 배터리셀 수명을 개선할 수 있는 방법을 제안한다. 기존 병렬접속회로로 구성된 배터리팩에서 전위차가 있는 배터리를 병렬접속회로에 의해 연결될 경우에 높은 전압 배터리셀에서 부하전류를 부담함과 동시에 낮은 전압 배터리셀을 충전하여 셀밸런싱을 동시에 수행하게 되면서 높은 배터리셀의 방전율 부담이 높아지게 되는 문제점을 지니고 있다. 전위차가 비교적 적으며 부하측에 흐르는 전류가 낮을 경우에 배터리 수명에 미미한 영향을 끼친다. 그러나 부하전류와 셀밸런싱 전류가 클 경우에는 배터리는 높은 방전율로 인하여 배터리수명 감소에 악영향을 끼치게 된다. 전위차가 있는 배터리셀을 연결하는 상황에서도 특정 배터리셀에 가중되는 방전 전류부담에 대한 편중을 줄여 배터리수명 감소를 최소화시킬 필요가 있다. 이는 배터리의 사용효율을 높이고 배터리의 안정적인 사용을 통해 배터리 비용 및 유지보수 비용을 줄이는 데 목적을 둔다. 상기 목적을 달성하기 위하여 제안한 배터리셀 병렬접속회로를 기존 병렬접속회로와 비교검토하고, 제안 병렬접속회로의 방전특성에 대한 유효성을 검증하기 위하여 시뮬레이션 및 실험 해석을 수행한다. In this paper, author proposes a method to improve the battery cell life by reducing the current burden on battery cell when a battery pack composed of lithium-ion battery cells is designed as a parallel connection circuit. In the case of a battery pack composed of battery cells with a potential difference by the conventional parallel connection circuit, higher voltage battery cell provides the load current and simultaneously charges the lower voltage battery cell for cell balancing, resulting in a higher discharge rate of battery cell. When the potential difference is relatively small and the current flowing to the load side is low, it has a slight effect on the battery life. However when the load current and the cell balancing current are large, the battery life is adversely affected due to the high discharge rate. Even in a situation in which battery cells with potential difference are connected, it is necessary to minimize the reduction in battery life by reducing the burden on the discharge current of a specific battery cell. This is aimed at reducing battery costs and maintenance costs for the operation of the battery by improving the utilization efficiency of the battery and at the stable use of the battery. To achieve the above objects, the proposed parallel connection circuit for battery pack is compared with the conventional circuit, and simulation and experimental analysis are performed to verify the effectiveness of the discharge characteristics of the proposed parallel connection circuit.