WDM(Wavelength Division Multiplexing) is called a wavelength division multiplexing optical transmission method and is a next-generation optical transmission technology. Case company F has recently developed and sold PLC(Planar Lightwave Circuit), a key element necessary for WDM system production. Although Chinese processing companies are being used as a global outsourcing strategy to increase price competitiveness by lowering manufacturing unit prices, the average defect rate of products manufactured by Chinese processing companies is more than 50%, causing many problems. However, Chinese processing companies are trying to avoid responsibility, saying that the cause of the defect is the defective PLC Wafer provided by Company F. Therefore, in this study, the responsibility of the PLC defect is clearly identified through estimating the defect rate of PLC using the sampling inspection method, and the improvement plan for each cause of the PLC defect for PLC yeild improvement is proposed. The result of this research will greatly contribute to eliminating the controversy over providing the cause of defects between global outsourcing companies and the head office. In addition, it is expected to form a partnership with Company F and a Chinese processing company, which will serve as a cornerstone for successful global outsourcing. In the future, it is necessary to increase the reliability of the PLC yield calculation by extracting more precisely the number of defects.

A lot of sensor and control signals is generated by an industrial controller and related internet-of-things in discrete manufacturing system. The acquired signals are such records indicating whether several process operations have been correctly conducted or not in the system, therefore they are usually composed of binary numbers. For example, once a certain sensor turns on, the corresponding value is changed from 0 to 1, and it means the process is finished the previous operation and ready to conduct next operation. If an actuator starts to move, the corresponding value is changed from 0 to 1 and it indicates the corresponding operation is been conducting. Because traditional fault detection approaches are generally conducted with analog sensor signals and the signals show stationary during normal operation states, it is not simple to identify whether the manufacturing process works properly via conventional fault detection methods. However, digital control signals collected from a programmable logic controller continuously vary during normal process operation in order to show inherent sequence information which indicates the conducting operation tasks. Therefore, in this research, it is proposed to a recurrent neural network-based fault detection approach for considering sequential patterns in normal states of the manufacturing process. Using the constructed long short-term memory based fault detection, it is possible to predict the next control signals and detect faulty states by compared the predicted and real control signals in real-time. We validated and verified the proposed fault detection methods using digital control signals which are collected from a laser marking process, and the method provide good detection performance only using binary values.

First Mover Advantage is already well known. It is when a company gains a position in a certain market or industry, or when it establishes a strong entry barriers through a distribution channel or a monopoly of resources. It is a concept that has been attracting attention for a long time in marketing and strategy. However, although it is possible for the starter to enjoy these various benefits, it is also true that there is a corresponding price. Therefore, the risks and costs that the starter may bear, and thus the relative benefits enjoyed by the latter, can be significant. Late Mover Advantage and so on. The fact that latecomers can enjoy a variety of benefits as well as the profits of the starters is an important consideration that must be taken into account by many companies considering entry into the market. In general, there is a very high risk of overinvestment in technology and market uncertainty. For example, China has skipped wired networks and went wireless, and many African countries have skipped wired communications and built infrastructure for wireless communications. In other words, companies that hastened to invest in fixed-line facilities in order to preoccupy the African telecom market are in a state of failure rather than expecting the interests of the starters. Another thing is that the starter has to bear more risks and costs than the latter, such as the uncertainty of demand, the risk of changing consumer preferences, and the cost of training new consumers. Also, because imitation is generally less costly than development, a latecomer entering through imitation may be in a better position if patents or other technical defenses are not available. Especially, if latecomers have excellent management ability and financial power such as excellent marketing ability, it is relatively easy to catch up with the first candidate.

In an automated industry PLC plays a central role to control the automation system. Therefore, fault free operation of PLC controlled automation system is essential in order to maximize a firm’s productivity. A prior test of control system is a practical way to check fault operations, but it is a time consuming job and can not check all possible fault operation. A formal verification of PLC program could be a best way to check all possible fault situation. Tracing the history of the study on formal verification, we found three problems, the first is that a formal representation of PLC control system is incomplete, the second is a state explosion problem and the third is that the verification result is difficult to use for the correction of control program. In this paper, we propose a transformation method to reproduce the control system correctly in formal model and efficient procedure to verify and correct the control program using verification result. To demonstrate the proposed method, we provided a suitable case study of an automation system.

The gingival epithelium of the oral cavity is constantly exposed to exogenous stimuli such as bacterial toxins, allergens, and thermal changes. These exogenous stimuli are resisted by innate host defense in gingival epithelial cells. However, it is unclear exactly how the exogenous stimuli affect detrimentally on the human gingival epithelial cells. Here, we investigated whether the allergen, such as house dust mite (HDM) extract, is linked to Ca2+ signaling and proinflammatory cytokine expression in primary cultured human gingival epithelial cells. HDM extract induced an increase in intracellular Ca2+ concentration ([Ca2+]i) in a dose-dependent manner. Extracellular Ca2+ depletion did not affected on the HDM extract-induced increase in [Ca2+]i. The HDM extractinduced increase in [Ca2+]i was abolished by the treatment with U73122 and 2-APB, which are inhibitors of phospholipase C (PLC) and inositol 1,4,5-trisphosphate (IP3) receptor. Moreover, HDM extract induced the mRNA expression of pro-inflammatory cytokine, interleukin (IL)-8. These results suggest that HDM extract triggers PLC/IP3-dependent Ca2+ signaling and IL-8 mRNA expression in primary cultured human gingival epithelial cells.

Paddy harrow machine used hydraulic actuator system has been changed to the electric actuator system method. Because driving system of the agricultural equipments has been changed to electric power system. Besides, the effort to reduce the tractor machine's horse power is proceeding rapidly. In this paper, pressure, load scale factor and loading force(dynamic, static force) are considered to determine the cylinder diameter of the electric actuator. The algorithms of paddy harrow machine was studied to control and test the components of link by using the PLC diagram. Also, the electric actuator mechanism system was evaluated through the PLC algorithm. These test results can be attributed to select the actuator capacity and to determine the reliability of the electric actuator system

A kind of field bus called Actuator and Sensor interface bus(AS-i) was designed in this paper. The configuration of AS-i network system used Application Specific Integrated Circuit(ASIC) SAP5S chip and PLC S7-200 station, which included CPU 224 and AS-i master module CP 243-2. We also created an example program for PLC S7-200 to control AS-i network. The fire and smoke detection system was made with AS-i network system that was designed. This system had got more advantages than other system such as number of stations, easy installation, wide working area, etc. And designed system can be used as a partner network for higher level field bus networks.

The latest cultivation research and development of seeding technology was improved because the demand for direct planting increased. The Programmable Logic Controller (PLC) and position sensor are utilized to control the seed detection system. In this paper, of seed types, RPM (Revolution per minute) variations and hole size are considered to determine the capacity of seeder hopper to meet the needs of customer demand. These algorithms were composed of the process of seed monitoring and the compulsion opening system. The capacity of seeding is assumed to be 1.53kg(11.6 liters) of rice seed per 1.8km. Therefore, this detection system can be used to determine the capacity according to seed types, RPM and hole size.

In an automated industry PLC plays a central role to control the manufacturing system. Therefore, fault free operation of PLC controlled manufacturing system is essential in order to maximize a firm's productivity. On the contrary, distributed nature of manufacturing system and growing complexity of the PLC programs presented a challenging task of designing a rapid fault finding system for an uninterrupted process operation. Hence, designing an intelligent monitoring, and diagnosis system is needed for smooth functioning of the operation process. In this paper, we propose a method to continuously acquire a stream of PLC signal data from the normal operational PLC-based manufacturing system and to generate diagnosis model from the observed PLC signal data. Consequently, the generated diagnosis model is used for distinguish the possible abnormalities of manufacturing system. To verify the proposed method, we provided a suitable case study of an assembly line.

This study was conducted to develop a system and an control algorithm for control the environment of a plant factory. The greenhouse control system for environmental control was largely composed of a computer and a PLC. The screen of control program was composed of a greenhouse figure which was included machinery and equipments for greenhouse, the graph of environmental factors of inside greenhouse and the image of greenhouse. In order to reduce temperature change, the operation time of ventilation window was changed by 3 stage according to difference between a target and present temperature. When is heating, a temperature variation was shown to be 16.7±0.8℃. When is cooling, a temperature variation was shown to be 23.1±0.6℃. When is humidifing, a humidity variation was shown to be 39.3±1.6℃ %RH. An environmental control system and a control algorithm were proved that it was shown a good performance in a control accuracy. So a computer control system should be adapted to a control system of a greenhouse and a plant factory.

본 연구는 사회과 관련 PLC(Professional Learning Community)에 참여 중인 초등 교사들을 대상으로 하여 PLC 참여경험의 의미를 밝혀보고자 하는 데 그 목적이 있다. 이를 위해 교과교 육적 관점에서 PLC의 개념과 속성을 정립하고, 사회과 관련 PLC에 참여 중인 교사들의 경험 을 통해 PLC 참여경험이 교사 개인의 사회과 전문성 신장에 어떠한 의의를 가지는지 논의해 보았으며, PLC라는 교사들의 협력적 활동이 교사들의 성장과 사회과 전문성 신장을 위한 교사 교육에 시사하는 바를 탐색해 보았다. 교사들의 PLC 참여경험의 양상을 분석한 결과 가장 먼저, 교사들이 사회과 PLC에 진정한 참여자가 되기 위해서는 구성원 간에 PLC가 추구하는 목적과 의도를 이해하는 합의의 과정이 필요하며 이를 통해 PLC 활동의 ‘가치’를 ‘공유’하여야만 진정한 참여가 일어남을 확인할 수 있었다. 둘째, 사회과 PLC 참여교사들은 사회과에 집중된 주제를 설정하고 공동으로 탐구하는 ‘학습’을 경험하였다. 셋째, 사회과 PLC 참여교사들은 초등 사회과 교사로서의 ‘정체성’을 찾아 가는 모습을 보였다. 이러한 교사들의 참여경험의 개인적 의미를 토대로 PLC라는 교사들의 공 동체적 활동의 특징과 의의를 상황학습이론과 자기생산이론을 바탕으로 탐색해본 결과 첫째, 사회과 관련 PLC는 ‘참여’와 ‘실행’을 통해 사회과 전문성을 함양하며 둘째, 사회과 관련 PLC 는 ‘대화’와 ‘접촉’을 통해 지식과 사고를 확장해 나감을 확인할 수 있었다.