• Journal of ILASS-Korea
• /
• v.23 no.2
• /
• pp.58-65
• /
• 2018

An analytic strategy to control the variable valve actuation applied to two intake valves (flow port intake valve and swirl port intake valve) was performed in this study. we considered the variation in phasing of intake valve profiles by using the Cam-in-Cam technology. The analytic model was implemented in the GT-Power simulation program and analyzed the result of regulated emissions such as, NOx and Soot, especially with IMEP characteristics. Namely, we meticulously investigated the sources of having effect on the amount of NOx and soot formation under the test conditions with retard timing of both flow port and swirl port intake valves for decreasing the opening duration by 35CAD. Also, we analyzed the effect of incylinder pressure and temperature with NOx variations and in-cylinder pressure and temperature on NOx variations and normalized turbulent intensity. Through this analysis, some useful results on the combustion and flow characteristics of the swirl port and flow port control of the intake valve were obtained by this study.

• Transactions of the Korean hydrogen and new energy society
• /
• v.25 no.1
• /
• pp.79-86
• /
• 2014

In Dimethyl Ether (DME) indirect production processes, DME have a reforming process to separate Methanol. DME has a high cetane number and Methanol has a high octane number. Each fuel has a different combustion characteristics and reactivity. So, this paper was investigated on the combustion characterisitics of DME and Methanol. Basically, Methanol has a effect of retarding ignition. However, Within 10% of total carbon mole number in DME, Methanol slightly changed the onset timing of Low Temperature Reaction (LTR) with increasing thermal-ignition preparation range. It means that controlling combustion phasing of DME can be possible without eliminated LTR. In case of IMEP, the ranges.

• Journal of Aerospace System Engineering
• /
• v.9 no.4
• /
• pp.16-22
• /
• 2015

Korea Aerospace Research Institute(here after KARI) has a plan to launch experimental lunar orbiter in 2018, and lunar orbiter and lander in 2020. There are several ways to go to the moon. Which one is direct transfer trajectory and another one is phasing loop transfer trajectory and the other one is WSB trajectory. Regardless of the transfer trajectories, LOI maneuver is the most important maneuver of all mission sequences because if this burn is failed, it is too difficult to get into the lunar orbit in the future. This paper describes first LOI target value of foreign lunar orbiters and analyzes orbital variations of experimental lunar orbiter according to various target values. By analyzing the variation of orbiter parameter after first LOI, proper orbital period for LOI target value are recommended to meet the inclination, apoapsis and periapsis altitude constraints.

• Journal of Digital Convergence
• /
• v.14 no.10
• /
• pp.535-542
• /
• 2016

This study was to explore the meanings and follow-up tasks for enactment of Act on Supply and Utilization Promotion of Assistive Technology Devices for People with Disabilities and Seniors(Assistive Technology Act) in Korea. I conducted analysis about contents and establishment process of the Act. The study found meaningful effects ; it provided the basis for supporting assistive technology devices based on the social model, it led to an Implementation of the national obligations such as UN Convention on the Rights of Persons with Disabilities, it provided terms related to assistive technology. It is suggested to conduct follow-up studies and to put the efforts to strengthen additional laws for backing up the effective policy for extended support of assistive technology devices and for security of budget, for establishing regional service centers, for phasing of professional qualification, for controlling quality, for establishing an information system, and for promoting industries.

• Journal of Korean Society of Transportation
• /
• v.19 no.3
• /
• pp.75-88
• /
• 2001

Signal optimization model for alternative use of lanes at a signalized intersection with an stop-line added backward was presented in this paper. The simulation results shot-ed that the traffic fed from the stop-line passed the intersection in each specified phasing interval for left and through traffic. The experimental results indicated that the proposed model was much superior to traditional signal optimization methodology in reducing delay, fuel consumption, and disutility index for delay and stops. The effects for reducing delay were greater than those for doing fuel consumption and disutility index due to the added stop-line. The proposed model is expected to alleviate traffic congestion at intersections, both which have no left turn pocket, and which have large left turn volume. The model is recommended to adapted for intersections spaced long among them with no near driveway.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.18 no.2
• /
• pp.127-142
• /
• 1990

Comparative studies on the quality of life, a new research specialization,have emerged only in recent years and are experiencing vigorous development in many parts of the world This study is a two year phasing-in project carried out by a jointed research team between Seoul National University and Tokyo University. As the first study of the project series, the aim of the study is to learn how different the quality of life(QOL) between Seoul and Tokyo and how the students of both cities assign the relative weights to parameters of the quality of life in their cities. The study also attempts to illustrate the current state of the art in this new field. Seoul and Tokyo are located very closely bur their physical, socia-economic and cultural aspects are not the same but rather different. Here is our interest and the reason why we started out study. The study is divided into the following two principal parts: (1 ) The survey of the variables influencing the puality of life in Seoul and Tokyo (2) The survey of the attitude of students towards the relative importance of parameter of the quality of life in Seoul and Tokyo. The researches of the variables were carried out utilizing the existing official statistics derived from 1988 Seout Statistical Year Book and 1987 Tokyo Statistical Year Book. Therefore, the choice of indicators was largely limited to data that had been compiled in two yearbooks. The attitude surveys of students were carried out by interview. The questionnaire consists of a face sheet and a question which is designed to produce information on the relative importance of the parameters by the paired comparison method.

• Environmental and Resource Economics Review
• /
• v.21 no.3
• /
• pp.543-572
• /
• 2012

This paper compared historical energy use from 2000 between Japan and Korea and reviewed literature of mid-and long-term low carbon energy scenarios and plans in both countries released since 2000. In terms of energy use pattern, there are similarities between Korea and Japan; high dependence on energy imports, high proportion of manufacturing industry among OECD countries, closed electricity system disconnected with foreign countries, and high proportion of nuclear power generation with low proportion of renewable electricity despite of high potential of renewable energy. Differences are as follows; decreasing trend in Japan and increasing trend in Korea in terms of energy demand and supply, difficulty of exchanging electricity between regions in Japan unlike Korea, and prospect of nuclear power, that is, curtailing in Japan while expanding in Korea according to governmental plan. Energy Basic Plan in both countries established before nuclear accident in Fukushima required expanding about two times of nuclear energy by 2030, while civil society's energy scenarios suggested reducing energy demand, phasing-out nuclear power, and expanding renewable energy. This paper will serve as a base for future studies about long-term energy scenarios and plan in Japan and Korea.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.54
• /
• pp.235-260
• /
• 2012

The CMI Rules for Electronic Bills of Lading were based on sound principles that are now reflected in the provisions of the Rotterdam Rules, which provide for the use of electronic equivalents to bills of lading. Services involving bills of lading which exist in electronic form for at least part of their lives, and which use encryption to guarantee integrity and security of these electronic records, are already being offered by a number of carriers, among them APL. The relative success of APL's system demonstrates that the use of a system which embodies the basic ideas and processes underlying the CMI Rules could easily become a practical reality in the near future. The basic principles in the CMI Rules and the Rotterdam Rules adopt a minimum requirements approach and does not flesh out the details of procedures for the use of electronic bills. This is an improvement, as it allows adaptability to future technological developments. Successful electronic bill of lading systems can only be developed in response to customer demand, and carriers are in the best position to gauge this and design systems to cater for it. APL has demonstrated this by creating a system which is tailor-made to its customers' requirements. The CMI Rules were correct in their assumption that electronic bill of lading services should be provided by carriers. They also seem to have anticipated that the switch to the electronic medium would not be sudden and complete, but would require a gradual phasing out of paper documents over a long period of time.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.14 no.6
• /
• pp.1273-1279
• /
• 1994

There are 3 cases that only permissive left-turn(PLT) vehicles use the possible lane for PLT. In these cases, left turn and through movements can not be included in the same lane group, hence saturation flow rate and left turn adjustment factor of PLT are obtained separately from through movement. In capacity analysis procedures at signalized intersection with PLT phasing, PLT capacity should be known to discriminate among 3 cases stated above. The capacity is directly used not only to get saturation flow rate and left turn adjustment factor, but as a threshold for the feasibility of PLT control. This study calculated through field data the critical gap and minimum headway of left turn which affect the PLT capacity. The capacity was obtained by using theoretical models, which consequently could be used to calculate the saturation flow rate and left turn adjustment factor.

• The Korean Journal of Nuclear Medicine
• /
• v.20 no.1
• /
• pp.25-31
• /
• 1986

This study was performed to establish normal hepatoscintiangiographic(HSA) pattern of hepatic blood flow and to investigate dynamic differential HSA findings of primary and metastatic carcinomas and abscess of the liver. HSA was carried out after intravenous bolus injection of 10 mCi of Tc-99m-phytate by obtaining sequential anterior images of 1-second exposure for 16 seconds. Observations included (1) baseline study of normal hepatic blood flow pattern by correlating with contrast angiogram, (2) time sequence phasing of normal HSA, and (3) analysis of altered patterns in primary and metastatic carcinomas and abscesses of the liver. Materials consisted of 20 normal subjects, 28 primary hepatocellular carcinomas, 16 metastatic carcinomas and 7 liver abscesses. Results were: (1) Normal HSA demonstrated 3 distinct phases of arterialization(AP), of arterial hepatogram(AHP), and of portal venous hepatogram(PVHP). The means of each phase were 5.3, 6.3 and 8.3 seconds, respectively. Portal vein could be seen in all but one of 20 normal subjects. (2) Pattern changes in diseases groups were early start of AP in carcinomas and very early start of AP in abscesses. AP became prolonged in all disease group. (3) Distinction between AHP was sharp in metastasis and abscesses but un sharp in primary hepatoma. Cold area or areas became vascularized in primary hepatoma but not in abscess. Cold areas of metastasis were inhomogeneously vascularized in late AP and throughout AHP and became relatively vascular as PVHP began. The cold area of abscess showed rim enhancement during AH and APH. These differences in HSA pattern were very useful in differential diagnosis of the diseases studied.